Control of transmission power between base station and mobile station in mobile communication system

The present invention relates generally to a mobile communication system, and in particular, to a method of power control between a base station and a mobile station in a CDMA mobile communication system.

BACKGROUND ART Existing mobile communication system with multiple access, code-division multiplexing (CDMA) mainly provides voice service data. However, it is not difficult to foresee that in the near future, mobile telephony will be implemented in accordance with the IMT-2000 (International Mobile Telecommunications - 2000). IMT-2000 standard provides not only voice service data but also high speed packet service data. For example, the IMT-2000 standard provides high-quality voice transmission service of data transmission service to a moving picture search service on the Internet, etc.

In the existing CDMA mobile communication system, upon completion of data transmission, a channel used for data transmission is released. Then, when you want to resume the transmission of the data channel connection is restored in response to a channel request message for data transmission. However, due to the reduction of a compound through a channel when providing a packet data service as well as voice data transmission services existing system has an increased time delay, which makes it difficult to provide transmission services of high quality voice data. Therefore, a method for providing an improved packet service with reduced time delay. If there is a discontinuous transmission channel (PP) data, packet data is transmitted periodically. The service provides packet data transmission, after transmission of a data packet takes place non-transmission interval preceding the next transmission of a data packet. The non-transmission interval existing system releases or maintains the channel; the release of the channel leads to the time delay in the reduction of the compound of the channel, and the channel support leads to a waste of channel resources and increasing unnecessary interference to other channel.

SUMMARY OF THE INVENTION Therefore, object of the present invention is to provide a method for power control for the transition from a state in which there is no data in the state in which data can be transferred immediately to the mobile communication system. Another object of the present invention is to provide a process of transition from the slotted substate to the normal polsostoyaniya of which can easily go into the active state.

Another object of the present invention is to provide a method of effectively controlling transmission power of a base station and a mobile station in a mobile communication system.

It should be noted that this invention describes the case of slotted substate. However, this invention is applicable to all channels, PP CDMA mobile communication system including an IMT-2000 system. An example can serve as a channel PP UWC (dedicated control channel) and DC (additional channel). PCO is used in control hold state and active state (data transmission state), and the DC is used only in the active state. In both of the two channels can be discontinuous transmission message. In the absence of data to be transmitted on the PG channel, it is usually carried transmission power control signal. However, when a message is not transmitted for a long time, there is a specific problem (release of the channel causes a time delay and continuous transmission increases interference). Thus, this invention is applicable to all channels, PP, including DCCH and DC maintaining period of non-transmission with no power control. To solve the above problems mobile communication system according to the present invention controls the transmission power to radio communications between a base station and a mobile station. The method of the present invention includes (1) the assignment of the direct and reverse dedicated control channels, respectively, of the base station and the mobile station and the transmission power control of the forward and reverse dedicated control channels, so that on the respective channels could receive data; (2) interrupt the transmission power control, when data to be transmitted is not generated within a predetermined time; and (3) performing power level arbitration which involves the resumption of the transmission power control forward and reverse channels PP in a state in which transmission power control is interrupted (see. step 2), for controlling the transmission power so as to be able to re-transmit / accept data generated through the appropriate channels.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which like elements are designated by the same numbers.

FIG. 1 is a block diagram illustrating a channel structure of the base station and the mobile station corresponding to the example of the present invention.

FIG. 2 is a diagram illustrating transitions between states of the mobile communication system according to an embodiment of the present invention.

FIG. 3 is a diagram describing the transition from the normal substate control hold state to the slotted substate.

FIG. 4A and 4B are diagrams describing power level arbitration performed by a scheduled time (i.e., scheduled power level arbitration), according to Example of the present invention.

FIG. 5 is a diagram illustrating the case where power level arbitration is performed only when the base station or the mobile station has data to transmit (i.e. irregular power level arbitration), according to Example of the present invention.

FIG. 6 is a diagram illustrating the case when, during the regular power level arbitration whenever there is data to be transmitted, the power level arbitration is performed according to an embodiment of the present invention.

FIG. 7 is a flowchart illustrating a transition from the slotted substate to a normal substate according to an embodiment of the present invention; FIG. 8 is a flowchart illustrating the power level arbitration is performed when the mobile station requests the power level arbitration to transmit / receive data; FIG. 9 is a flowchart illustrating the power level arbitration is performed when a base station requests the power level arbitration to transmit / receive data; FIG. 10A-10B are diagrams illustrating methods for detecting channel conditions after a transition to the normal substate; FIG. 11A- 11B are diagrams illustrating a change in transmission power and the power control bit with the passage of time during the power level arbitration; 12A and 12B are diagrams illustrating a change in transmission power and the power control bit with the passage of time in the case where power level arbitration is performed at the request side having data to transmit in the slotted substate; FIG. 13A and 13B are diagrams illustrating signaling messages transmitted via the pilot channel and the uplink dedicated control channel in the forward link during the power level arbitration; 14 is a block diagram illustrating a scheduled power level arbitration performed by a base station according to an embodiment of the present invention; 15 is a block diagram illustrating a scheduled power level arbitration performed by a mobile station according to an embodiment of the present invention; FIG. 16 is a block diagram illustrating an irregular level arbitration, power exercised by the base station according to an embodiment of the present invention; FIG. 17 is a flow diagram illustrating power level arbitration irregular, wasps uschestvlyaemy mobile station according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED advantageous embodiment example of the present invention will be described below with reference to the accompanying drawings. In the following description, well known functions or constructions are not described in detail so as not to obscure the invention in unnecessary detail.

As used herein, the term "power level arbitration" (or transmission power level restoration) can be determined as follows. If for a long time function assigned channels between base station and mobile station power control is not performed, the base station and the mobile station can not establish an appropriate transmission power level when necessary renewal data. Thus, the communication system controls transmission power of a base station and a mobile station to an appropriate transmission power through a power adjustment process. This transmission power adjustment process is referred to herein as "power level arbitration". For example, power level arbitration is applicable to message transmission over a dedicated control channel in a CDMA mobile communication system. Further, the term "appropriate transmission power" indicates the transmit power level at which the receiver can normally receive the message.

Korean Patent Application N 11381/1998, filed by the applicant of the invention, a channel structure is considered, according to which the base station (BS) and mobile station (MS) have their own dedicated control channels, during the implementation of the transmission of data on the traffic channel, the base station and the mobile station exchange control signals for the traffic channel using the dedicated traffic channels. However, when the transmission of data is idle for an extended period of time, a transition to the control hold state, wherein the traffic channel is released and only supported by the dedicated control channel, which prevents waste of traffic channel resources. In addition, if the control hold state, the data to be transmitted, a traffic channel is immediately restored. Such a state of retention management is divided into two sub-states: a normal substate and a slotted substate. In the normal substate, the data to be transmitted is absent and there is only exchange of control signals via the dedicated control channel. If within the specified time data to be transmitted is not generated, a transition to the slotted substate. In the slotted substate supported resources dedicated control channel (orthogonal code, service capabilities, point-to-point protocol (PDTS) and the like), but the exchange of control signals and power control bits over a dedicated control channel is not carried out, to the mobile station does not consume power by continuous exchange of signals in the absence of data to be transmitted, as in the existing art. Therefore, for a transition from this slotted substate back to the normal substate, between the base station and the mobile station must perform the power level arbitration.

In an exemplary embodiment, a system in the slotted substate will switch to the slotted substate in the case where a normal power control is not carried out for a long time due to lack of data, which the base station and the mobile station could exchange. If necessary to transmit a control message to be adjusted to an appropriate transmission power of the transmission power that the receiving party can normally receive the message transmitted from the transmitting side. In this case, the power level arbitration is performed prior to the transition from the slotted substate to the normal substate.

Furthermore, in this case, transmission power control is performed so that the receiving party can normally receive the message transmitted from the transmitting side.

The structure of the channel after the call setup FIG. 1 illustrates respective channels and channel transceivers which are used between the base station and the mobile station after call setup in a CDMA communication system according to an embodiment of the present invention. For simplicity, channels used during the call setup, Fig. 1 are not shown.

In some cases, the functions of the respective channels may be varied. In particular, power control bits (or power control signals) and preamble signals can be transmitted not only by a special channel but also other channels, but for convenience, assume that the power control bits and header bits transmitted on a particular channel.

FIG. 1 illustrates a channel structure for the base station and the mobile station.

At the base station, a dedicated channel generator 10 processes various control signaling messages to be transmitted over a dedicated control channel, the downlink (P-DCCH) and transmits the processed signaling message to the mobile station. Channel generator 12 processes a pilot signal to be transmitted on a pilot channel downlink signal (P CPS) and transmits the processed signal to the mobile station. The signal transmitted on the pilot channel of the forward link, the mobile station makes an initial data acquisition and channel estimation. Fundamental channel generator 14 processes information to be transmitted on the fundamental channel forward link (P-OC), and transmits the processed information to the mobile station. Information transmitted on the fundamental channel forward link mainly includes a voice signal, but can also include various signaling messages to level 3 and the power control bits that are used in the standard IS-95B. Supplemental channel generator 16 processes information to be transmitted on an additional forward link channel (P-DK) and transmits the processed information to the mobile station. The information transmitted on supplemental downlink includes frames RLP (radio link protocol) and packet data.

At the mobile station, generator 30 processes the dedicated control channel signaling messages to be transmitted over a dedicated control channel uplink (O-DCCH) and transmits the processed signaling message to the base station. Channel generator 32 processes a pilot signal to be transmitted on a pilot channel uplink (O CPS) and transmits the processed signal to the base station. The signal transmitted on the pilot channel uplink makes the base station to carry out the initial data acquisition and channel estimation. Moreover, the signal reverse pilot channel signal can carry the power control bits to supply the base station power control information pertaining to direct channels. In addition, the reverse link provides for the possibility of transmission of power control bits by introducing them into the pilot channel, without assignment of a separate channel. Fundamental channel generator 34 processes information to be transmitted on the fundamental channel uplink (D-OK) and transmits the processed information to the base station. Information transmitted on the fundamental channel uplink, basically includes a voice signal. Supplemental channel generator 36 processes information to be transmitted on supplemental channel uplink (D-DK) and transmits the processed information to the base station. Information transmitted on the supplemental channel uplink includes RLP frames and packet data.

The CDMA mobile communication system illustrated in FIG. 1, for a service connection with the transmission of packet data, the base station uses the pilot channel, wrought control channel and the supplemental channel forward link and the mobile station being uses pilot channel, the dedicated control channel and supplemental channel uplink, in this case, the base station transmits the power control bits on the forward dedicated control channel, and the mobile station transmits the power control bits, inserting them in the reverse pilot channel. Furthermore, the controller 18 adders 20 and 22, modulator 24 and receiver 26 of expansion for the base station, and a controller 38, adders 40 and 42, modulator 44 and receiver 46 of expansion for the mobile station are described in detail in Korean patent application 11381/1998, filed by the applicant invention.

State transitions of the channel Fig. 2 illustrates state transitions of the base station and the mobile station. Since the present invention relates generally to power control in a control hold state, the following description focuses on the control hold state.

Referring to FIG. 2, in the control hold state, a traffic channel for the packet data is released because of the absence of actual data to transmit, and a dedicated control channel is maintained to exchange the control signals. According to the picture, the state retaining control is divided into two sub-states, a normal substate and a slotted substate. In the normal substate, the control signals are exchanged via the dedicated control channel in the presence of a control signal to be transmitted. In the absence of control messages to be transmitted are transmitted only normal power control bits to maintain normal power control. If the control message is not generated for a predetermined time, the normal substate retention of control proceeds to the slotted substate retain control in the slotted substate supported resources dedicated control channel, but the exchange of control signals and power control bits along tanned established control channel is not performed.

According to Figures 1 and 2, in the control hold state the base station maintains the pilot channel (in fact, a direct bit signal is always transmitted) and the dedicated control channel of the downlink, and the mobile station maintains the pilot channel and dedicated control channel uplink . In the normal substate, the control signals are exchanged via the dedicated control channel. However, in the slotted substate, although the dedicated control channel resources are maintained and that control signals are transmitted over a dedicated control channel due to lack of a control signal. If it is segmented substate lasts for a while, with the passage of time will change the state of the channel. After some time, if the control message is transmitted at a transmission power established much earlier, the receiving party can not normally restore the received message.

If in the normal substate state retention control data to be transmitted is not generated within a predetermined time, a transition to the slotted substate. In the slotted substate, although the dedicated control channel and supported the exchange of control signals, and bits of continuous power control is not carried out to prevent waste of resources and an increase in unjustified interference.

An exemplary transition from the normal substate to the slotted substate will be described with reference to Figure 3. 3, "normal" refers to work in the normal substate, and "Standby" - operation in the slotted substate.

The transition from the normal substate to the slotted polsostoyaniya In FIG. 3, when the normal substate is maintained for a predetermined time without transmission of control signals or data (m. E. Before the expiration of the timer), the mobile station transmits a request signal waiting mode (i.e., a request signal for a transition to the slotted substate) to the base station over a reverse dedicated control channel (R-DCCH). In the normal substate, the mobile station uses the dedicated control channel and the pilot channel uplink, and the base station uses the dedicated control channel and the pilot channel of the forward link. In the normal substate, since power control is carried out in the normal way, the power level arbitration is required. Having standby request signal from the mobile station, the base station transmits ACK waiting mode (i.e., an acknowledgment signal transition to the slotted substate) to the mobile station via forward dedicated control channel (F-DCCH), and then proceeds to the slotted substate. Having ACK signal standby mode transmitted from the base station, the mobile station switches to the slotted substate. Turning to the slotted substate, the base station and the mobile station maintains the resources, respectively, the forward and reverse dedicated control channels, but do not exchange control signals via the forward and reverse dedicated control channels. Therefore, normal power control is not performed.

In some cases, the base station and the mobile station can move to the slotted substate directly using their own internal timers that give a signal if a control message is transmitted or received without the above coordination for the transition states.

If the slotted substate is maintained for a predetermined time, and if the base station or the mobile station generates data to transmit, a transition back to the normal substate from the slotted substate, in accordance with the method of the present invention are described below with reference to FIG. 4-17.

The transition from the control hold state to the active state according to FIG. 2, active packet data communication is carried out on the traffic channel, while control signals are exchanged via the dedicated control channel. The transition from the control hold state to the active state can occur in two ways: (1) the transition from the normal substate state retaining control in the active state, and (2) the transition from the slotted substate hold state to the active state control. With regard to the first (1) transition, when data to be transmitted is generated in the normal substate, control hold state, the base station and the mobile station exchange control signals on the dedicated control channels for the purpose of traffic channel assignment for the transmission of packet data. By establishing the traffic channel is a transition to the active state when packet data is exchanged over the assigned traffic channel.

Regarding the second (2) transition, a transition from the slotted substate control hold state to the active state occurs through the normal substate. Referring to FIG. 1, in the active state, the base station and the mobile station can use the supplemental channels and fundamental channels as well as the pilot channels and dedicated control channels. If during a predetermined time in the control hold state, data to be transmitted, a transition occurs from the control hold state to the standby state.

In the idle state a dedicated control channel is released and a common channel is used. In other words, if for a given time can not move from the slotted substate hold state management in an active state, a transition to the standby state, wherein the resource dedicated control channel (orthogonal code), which was maintained in the slotted substate, is released and the transmission of control signals It is performed using a common channel. The transition from the slotted substate to the standby state also occurs through the normal substate hold state administration to send a message about the transition states. In the standby state, service information (or service capabilities) between the base station and the mobile station is preserved (or maintained). If within a predetermined time in the idle state there is no data to be transmitted, then a transition from the idle state to the inactive state.

The inactive state similar to the state of standby that released the dedicated control channel resource (orthogonal code), and uses a common channel. However, inactive service capabilities between the base station and the mobile station is no longer maintained. If in an idle state for a predetermined time is no data to be transmitted, then a transition from the inactive state to the zero state.

In the zero state to the base station and mobile station is powered on, and they expect a request for the data service, which must deal with the other side. Null state is a kind of wait states in the active state, control hold state, an idle state and an inactive state maintained initialization information between the base station and the mobile station. However, the zero-state information initialization (system parameters BSs electronic serial number (EPA), and so on. G.) Between the base station and the mobile station is not saved, after the transition from state retention control in the zero state, all information is maintained between the base station and the mobile station is released.

A more detailed description of the respective states and state transitions can be found in Korean Patent Application N 2263/1998, filed by the applicant of the invention.

The transition from the slotted substate to the normal substate by using power level arbitration The present invention is an improved process for arbitration and transmission power level for transition from the slotted substate control hold state to the normal substate. Arbitration is described in accordance with the following three embodiments.

(1) Overview of the three examples of the first embodiment, the power level arbitration between base station and mobile station is performed at the scheduled time regardless of the presence or absence of data to transmit (i.e., scheduled power level arbitration).

According to a second embodiment, the power level arbitration is performed for the transition from the slotted substate to the normal substate only when necessary to transmit data (i.e., irregular power level arbitration). This embodiment can, in turn, be divided into two cases: (1) the case where power level arbitration is performed for the transition to the normal substate, the presence at the mobile station has data to transmit, and (2) the case where power level arbitration It is performed for the transition to the normal substate when the base station has data to transmit.

The third embodiment is a combination of the first and second embodiments. According to this embodiment, during a periodic or non-periodic arbitration process the power level carried out at the scheduled time between the base station and the mobile station, if necessary, transmit data immediately arbitrates power level for transition from the slotted substate to the normal substate, regardless of the planned time. Three examples of the power level arbitration (or power level of recovery) are shown in Figure 4 (4A and 4B), 5 and 6, respectively. Specifically, FIG. 4A and 4B illustrate a first embodiment of the power level arbitration at the scheduled time between the base station and the mobile station. FIG. 5 illustrates a second embodiment of power level arbitration for transition from the slotted substate to the normal substate only when the base station or the mobile station has data to transmit. FIG. 6 illustrates a third embodiment, and when during the regular power level arbitration when there is data to transmit, for the transition from the slotted substate to the normal substate immediately performed power level arbitration.

The above three kinds of power level arbitration performed between a base station and mobile station via forward dedicated control channel and reverse pilot channel using power control bits. The base station receives the power control bit transmitted from the mobile station measures the received power level and generates a power control bit to the mobile station to transmit the generated power control bit for controlling transmission power level of the power control bit generated in the mobile station. The mobile station, in turn, receives the power control bit transmitted from the base station measures the received power level and generates a power control bit to the base station to transmit the generated power control bit for controlling transmission power level of the power control bits generated at the base station. It is not necessary to transmit only the power control bit. According to another embodiment shown in FIG. 13A, the mobile station may transmit a header (pilot) signal including power control bit.

First Embodiment FIG. 4A and 4B shows the distribution of power level arbitration in the case where the power level arbitration performed at a scheduled time between the base station and the mobile station. Both the base station and the mobile station has information regarding the scheduled power level arbitration time. The power level arbitration process is simultaneously performed at every scheduled power level arbitration time. Specifically, FIG. 4A shows the case when the set time of the periodic power level arbitration, power level, and arbitration is performed for each interval of the periodic power level arbitration. FIG. 4B shows the case where time set nonperiodic power level arbitration, power level, and arbitration is performed in each interval nonperiodic power level arbitration, which is known to both the base station and the mobile station.

FIG. 4A, TR denotes a time interval during which the power level arbitration, and T11 is a fixed time interval the power level arbitration. FIG. 4B, T12 is a fixed time interval, and TR and T13 represent intervals when carried out, respectively, and the power level arbitration nonperiodic power level arbitration. According to Figure 4B, for each time interval T13 is carried nonperiodic power level arbitration. Referring to FIG. 4A and 4B, if during the time TR can not perform the power level arbitration, the new power level arbitration attempt is undertaken during the next time interval the power level arbitration.

In the case of a regular power level arbitration shown in Fig. 4A and 4B, it is possible to reasonably estimate the delay due to confirm (RTD) between the base station and the mobile station, based on a prior power level arbitration, and thus reduce the size of the search window for receiving signal. In this case, the FOD is a time delay that the base station is necessary to accept a response signal after transmitting a signal to the mobile station.

Reducing the size of the search window reduces the power level arbitration time. However, regular power level arbitration, when data to be transmitted is generated within a time interval T11, the power level arbitration to transmit the generated data to be expected, when the time of the next power level arbitration. Furthermore, even when no data is generated for transmission, the power level arbitration is performed at every scheduled power level arbitration time, causing interference.

Second Embodiment FIG. 5 shows the distribution of power level arbitration in the case where power level arbitration is performed only when the base station or the mobile station has data to transmit (i.e. irregular power level arbitration). In this case, the base station or a mobile station having data to transmit, initiates the power level arbitration. FIG. 5 T21, T22 and T23 indicate the time intervals between noncyclic arbitrate power level that can not be predicted since the power level arbitration is performed whenever the base station or in the mobile station there is data to be transmitted. Referring to FIG. 5, if a predetermined time TR can not perform the power level arbitration, taken immediately retrying the power level arbitration.

Referring to FIG. 5, since the power level arbitration is performed only when necessary to transmit data, it is possible to prevent waste of system resources, which occurs in the first embodiment. When the power level arbitration is performed after a long period of inactivity in the slotted substate, it is impossible to predict the RTD between the base station and the mobile station in effect mobility of the mobile station. As a result, the size of the search window of the received signal increases, which leads to an increase in the power level arbitration time.

Third Embodiment FIG. 6 shows the distribution of power level arbitration, according to an improved method for power level arbitration, combining methods of the two previous exemplary embodiments. According to this embodiment, in addition to performing the regular power level arbitration, power level arbitration is additionally performed whenever there is data to be transmitted, in order to quickly transition states for data transmission. Referring to FIG. 6, (1) if a period of time TR can not perform the power level arbitration, the system rejects the power level arbitration; (2) if the power level arbitration is performed periodically retrying the power level arbitration is undertaken during the next power level arbitration period; (3) if it can not perform the power level arbitration within the time TR, the power level arbitration is when the need for data transmission is undertaken immediately retrying the power level arbitration.

Thus, as noted above with reference to the first embodiment and FIG. 4A and 4B, the periodic power level arbitration implementation is possible to predict the RTD, which reduces the power level arbitration time. However, if the data to be transmitted is generated before the power level arbitration time, to transmit the generated data to wait until the time comes next power level arbitration. Referring to FIG. 5, as stated above, the power level arbitration is performed only when there is data to transmit, preventing increase of interference to other users. However, a long period of inactivity in the slotted substate increases the power level arbitration.

Accordingly, combination of the processes of the first and the second makes it possible not only to quickly perform the power level arbitration due to periodic power level arbitration but also to immediately perform the power level arbitration whenever a need to transmit the generated data so as to quickly make a transition from the slotted substate to normal substate to transmit the generated data. In this case, the period of the periodic power level arbitration can be reduced compared with the case shown in FIG. 5A and FIG. 5 B.

FIG. 7-9 are flowcharts illustrating the power level arbitration process is carried out between the base station and the mobile station corresponding to the above three exemplary embodiments.

FIG. 7 illustrates an exchange of messages, corresponding to the first of the examples used. FIG. 7 illustrates the power level arbitration process in the case of scheduling a power level arbitration time between the base station and the mobile station. In the slotted substate, the base station transmits to the mobile station the power control bit with an appropriate initial power at a time scheduled between the base station and the mobile station to produce a power arbitration for transition to the normal substate. At the same time, the mobile station also transmits to the base station power control bit with an appropriate initial power. The initial transmit power on the reverse link should be low enough so as not to adversely affect the system. Nachalnuyuya transmission power of the mobile station, Pms, we can determine how Pms = (1-I constant) - (total received power) or Pms- = (2nd constant) - (ave. Pilot power from a base station in communication ) limit the initial base station transmission power on the forward link is not as severe as for the mobile station. To establish the initial base station transmission power can be used several ways. According to one method, it is assumed that the base station transmits the power control bit with a specific initial power. The specific initial power can be determined in accordance with transmission power Pvs pilot betray base station on the pilot channel of the forward link, which is expressed by formula (3). According to the second method, the base station transmits the power control bit with the maximum power. The maximum power of the base station is preset to the maximum value in a range in which the base station does not cause interference to other cells. When the base station transmits the power control bit with the maximum initial power, the transmission power control of the mobile station will precede the transmission power control of the base station, reducing the impact on the system. The mobile station is easier to accept the power control bit transmitted from the base station than base station. Therefore it is better to control transmission power of the MS Sun, rather than vice versa. (See. FIG. 12B, T2) Pvs = (Trans. Pilot power of the base station) / (third constant) In the formulas (1) - (3) first, second and third constants can be experimentally set to the optimal values ​​corresponding to the system bandwidth.

Referring to FIG. 7, since power level arbitration is performed during scheduled intervals, the base station and the mobile station can know whether the other party transmits the power control bit even though it fails to receive the power control bit transmitted from the other party. In this case, when you can not take the power control bit transmitted from the other party, the base station or the mobile station sends the other side of the control bit increase power by deciding that the transmission power of the other side below the threshold. If the mobile station and the base station receives the power control bit with an appropriate power, then the power level arbitration is completed. Then, if necessary, can occur a rapid transition from the slotted substate to the normal substate. The reason is that the transfer of the state transition message can be a high degree of reliability since the initial transmission power set to the optimum level. Referring to FIG. 7, in the normal substate when the base station or at the mobile station has packet data to transmit, a transition to the active state to transmit the packet data. However, in the absence of a base station and a mobile station packet data to be transmitted, after a predetermined time, or the exchange state transition message is a transition to the slotted state. When this reverse link power control bit can be transmitted via the pilot channel; on the forward link power control bit can be transmitted over a dedicated control channel.

FIG. 8 and 9 show ways of irregular power level arbitration, according to which the power level arbitration is performed only when the base station or the mobile station has data to transmit. Specifically, FIG. 8 shows the case where the power level arbitration to exchange data is initiated by the mobile station, and FIG. 9 shows the case where the power level arbitration to exchange data with the base station initiated.

Referring to FIG. 8, in the slotted substate, if there is data to be transmitted, the mobile station transmits to the base station power control bit with a sufficiently low initial transmission power with the purpose of power level arbitration. The mobile station transmits the power control bit, gradually increasing the transmission power with the purpose of power level arbitration until the base station is not received the power control bit. Having power control bit in the slotted substate being, the base station transmits the power control bit to the mobile station with a initial power corresponding to the received power control bit.

In the case where the initial transmission power of the base station is inversely proportional to the level of the power control bit transmitted from the base station, the base station transmits control bits to power augmentation, gradually increasing the transmission power, until the mobile station does not change the transmission power in uplink according to the control bit power received from the base station.

Furthermore, in the case where the base station transmits the power control bit with an initial transmission power independent of the received power control bit, the base station transmits control bits backoff with the maximum transmission power, until the mobile station changes its transmission power according to the power control bit received from the base station.

Through this procedure, when the mobile station receives from the base station power control bit power level arbitration process is considered completed so that the base station and the mobile station can perform quick transition from the slotted substate to the normal substate exchanging state transition message.

In some cases, the mobile station fails to receive the power control bit reduction which base station has transmitted on the forward link by adopting the power control bit from the mobile station. In this case, the mobile station transmits the power control bit with the increased power, it decided that the base station itself could not take the power control bit transmitted from the mobile station. Although the base station has transmitted on the forward link power-down command, the mobile station continues to increase the transmission power, without being able to take transmitted command power reduction due to systemic problems within a given time interval. To solve this problem, the initial transmission power of the base station is set to its maximum power so that the mobile station can quickly take over from the base station the power control bit, thereby minimizing the danger interval. After the transition to the normal substate, the mobile station via an existing message on the state transition transitions to the active state to transmit data to the base station.

Referring to FIG. 9, when the slotted substate, the data to be transmitted, the base station indicates to the mobile station by the need to power level arbitration by transmitting its power control bit with an appropriate initial transmission power. As for the initial transmission power of the base station, see the associated description given with reference to Figure 7. By the power level arbitration, the base station gradually increases the transmission power to transmit the power control bit with the increased power until a mobile station is on will not be received the power control bit. If the power control bit received from the base station is a control bit more power, the mobile station responds to power increase command by gradually increasing the transmit power if the initial transmission power of the mobile station is set to a sufficiently low initial power. However, if the initial transmission power of the base station is set to its maximum transmission power, the mobile station continues to receive the power control bit with the maximum transmission power.

Deciding by the base station power control bit in the slotted substate, the mobile station transmits to the base station power control bit with an initial transmission power corresponding to the received power control bit. The mobile station continuously increases the transmission power until the base station is not accepted backoff control bit. Once the base station receives from the mobile station power control bit with an appropriate power, the power level arbitration is completed. Then, the base station and the mobile station carry out a quick transition from the slotted substate to the normal substate, because after the power level arbitration request message and state transition acknowledgment message can be transmitted with higher reliability. After the transition to the normal substate, the base station transitions to the active state to transmit the data to the mobile station.

Referring to FIG. 7-9, the base station and the mobile station exchange the power control bits to perform the power level arbitration. After the power level arbitration with subsequent transition to the normal substate, you can immediately detect the state of the channel.

FIG. 10A-10B are diagrams illustrating methods for detecting channel conditions after a transition to the normal substate, the process shown in FIGS. 7-9.

There are several methods for detecting channel conditions. According to a first method shown in FIG. 10A, the base station sends the mobile station a message (SVSCH) known to both the base station and the mobile station. According to the second method illustrated in FIG. 10B, the mobile station transmits to the base station a message known to both the base station and the mobile station. According to a third method illustrated in FIG. 10B, the base station and the mobile station simultaneously transmit to each other form them messages.

Referring to FIG. 10A, taking the message transmitted by the base station, the mobile station transmits an ACK signal. Taking a message indicating a failure or being unable to receive the message transmitted by the base station for a predetermined time, the mobile station transmits a NAK (negative ACK). Having ACK signal, the base station decides that the forward link and reverse link is in good condition. However, taking the NAK signal, the base station judges that the forward link is in a bad condition but the reverse link is in good condition. In addition to being unable to take any ACK signal or NACK signal, the base station can not decide which of the lines are in poor condition. The base station can merely presume that one of the two links or both of them are in poor condition.

Referring to FIG. 10B, receive the message transmitted by the mobile station, the base station transmits ACK signal. Taking a message indicating a failure or being unable to receive the message transmitted by the mobile station for a predetermined time, the base station sends a NAK signal. Having ACK signal, the mobile station decides that the forward link and reverse link is in good condition. However, taking the NAK signal, the mobile station judges that the reverse link is in a bad state, but a direct link is in good condition. In addition to being unable to take any ACK signal or NACK signal, the mobile station can not decide which of the lines are in poor condition. The mobile station can only assume that one of the two links or both of them are in poor condition.

Referring to FIG. 10B, the base station and the mobile station simultaneously transmit to each other form them messages. Then, taking a message transmitted from the other party, the base station and the mobile station transmit ACK signals to each other; taking failed message or not being able to take the message sent by the other party, the base station and mobile station transmits signals to the other side of the NAK. Having ACK signal, the base station decides that the forward link and reverse link is in good condition. However, taking the NAK signal, the base station judges that the forward link is in a bad condition but the reverse link is in good condition. In addition to being unable to take any ACK signal or NACK signal, the base station can not decide which of the two lines are in poor condition. The base station can merely presume that one of the two links or both of them are in poor condition. In addition, taking ACK signal, the mobile station decides that the forward link and reverse link is in good condition. However, taking the NAK signal, the mobile station judges that the reverse link is in a bad state, but a direct link is in good condition. In addition to being unable to take any ACK signal or NACK signal, the mobile station can not decide which of the two lines are in poor condition. The mobile station can only assume that one of the two links or both of them are in poor condition.

The method of FIG. 10A, allows the base station to detect the channel condition, so that this method is applicable to the case where the power level arbitration to transmit data initiated by a base station. The method of FIG. 10B, allows the mobile station to detect the channel condition, so that this method is applicable to the case where the power level arbitration to transmit data is initiated by the mobile station. The method of FIG. 10B allows both the base station and the mobile station to detect the channel condition, so that this method is applicable to a regular power level arbitration, according to which the power level arbitration performed at a scheduled time, even in the absence of data to be transmitted.

FIG. 11A-11B are graphs illustrating the variation of power transmission and power control bits over time during the regular power level arbitration. Specifically, FIG. 11A shows the case where the base station and the mobile station simultaneously receive the messages transmitted by the other party; FIG. 11B shows the case where the mobile station receives the message transmitted from the other party (i.e., base station) before the base station receives the message transmitted from the other party (ie. E. Mobile station); FIG. 11B shows the case where the base station receives the message transmitted from the other party before the mobile station receives the message transmitted from the other party. FIG. 11A-11B, the initial time T0 denotes a power level arbitration. Since the power level arbitration performed at a scheduled time regardless of the presence or absence of data to be transmitted, the base station and the mobile station simultaneously initiate the power level arbitration at the initial time T0, the power level arbitration. Further, T1 denotes the time when the mobile station receives the power control bit transmitted from the base station, and T2 denotes the time when the base station receives the power control bit transmitted from the mobile station.

Referring to FIG. 11A, the base station and the mobile station simultaneously receive the power control bits transmitted by the other party at the time T1 (= T2). Prior to receiving the power control bit transmitted from the other party, the base station and mobile station transmit power control bits with a gradual increase in transmission power. Having power control bits transmitted by the other party, the base station and the mobile station changes the transmission power of their respective in accordance with the power control bits. Sensing that the other party controls the transmission power according to the transmission power control bit, the base station and the mobile station exchange a state transition message and an ACK signal to make a transition to the normal substate.

Although the present invention has been described with reference to an embodiment which provides for the transmission of the state transition message and an ACK signal, as regards the state transition can also produce a state transition by informing an upper layer that the power level arbitration is completed in a physical layer.

Referring to FIG. 11B, the mobile station receives the power control bit transmitted from the base station at time T1. However, at this time, the base station can not receive the power control bit transmitted from the mobile station. Thereafter, the base station increases the transmission power little by little and transmits the power control bit at the increased transmission power level. The frame has 16 power control groups. Power control bit is transmitted in one power control group. The period of one power control group is 1.25 ms, so that an increase or decrease in power is performed every 1.25 ms. After the power level arbitration period, beginning from the time T2, when the base station receives the power control bit transmitted from the mobile station, the base station and the mobile station changes the transmission power according to the power control bits taken respectively from the other side. Sensing that the other party controls the transmission power according to the transmitted power control bit, the base station and the mobile station exchange a state transition message and an ACK signal to make a transition to the normal substate by deciding the completion of power level arbitration.

Referring to FIG. 11B, the base station receives the power control bit transmitted from the mobile station at the time T2. However, at this moment, the mobile station can not receive the power control bit transmitted from the base station. Thereafter, the mobile station increases the transmission power little by little and transmits the power control bit with the increased transmission power. With the advent of such a transition period, beginning at time T1, when the mobile station receives the power control bit transmitted from the base station, the base station and the mobile station changes the transmission power according to the power control bits taken respectively from the other side. Sensing that the other party controls the transmission power according to the transmitted power control bit, the base station and the mobile station exchange a state transition message and an ACK signal to make a transition to the normal substate by deciding the completion of power level arbitration.

Referring to FIG. 11A-11B, the initial transmission power is determined as described with reference to FIG. 7. The power level arbitration methods of FIGS. 11A and 11B, has no adverse effects on system performance, but the power level arbitration method of FIG. 11B, may adversely affect system performance. Referring to FIG. 11B, at time 12, when the base station receives the power control bit transmitted from the mobile station precedes the time point T1, when the mobile station receives the power control bit transmitted from the base station. The base station may receive the power control bit transmitted from the base station when the received power of the power control bit received from the base station is located at approximately the same level as that of the received signal power transmitted by other mobile stations, however, despite the fact that the base station transmits the power control bit by comparing the received signal power from the mobile station to the received signal power from other mobile stations, the mobile station can not receive the power control bit transmitted from the base station. Therefore, the mobile station will continuously increase the transmission power by deciding that the base station has transmitted the power control bit increase. As the interval between T2 and T1, the mobile station will transmit the power control bit with a transmission power much higher than an appropriate transmission power, wasting the transmission power. To solve this problem, it is preferable that the base station, from the beginning of the power level arbitration process, transmit power control bit with its maximum transmission power. Forward link channels is expanded by orthogonal codes (e.g., Walsh codes). Therefore, the base station may transmit to the mobile station the power control bit with the maximum transmission power without causing interference to other mobile stations. Transmitting the power control bit with the maximum transmission power, the base station may have a very low probability of receiving the power control bit transmitted from the other party before the mobile station receives the power control bit from the other party. Referring to FIG. 11A-11B, having power control bits from the other party, the base station and the mobile station can control the transmission power in different ways.

FIG. 12A and 12B are diagrams illustrating a change in transmission power time and the transmission power control bits time in the case where the power level arbitration in the slotted substate requested by a party having data to be transmitted. Specifically, FIG. 12A shows the case where the mobile station requests the power level arbitration to transmit data, and FIG. 12B shows a case where the base station requests the power level arbitration to transmit data.

Referring to FIG. 12A, if the slotted substate to the mobile station has data to transmit, the mobile station transmits the power control bit to the base station, to implement the power level arbitration. The initial transmission power to transmit the power control bit is set low enough so as not to adversely affect the system. As for the initial transmission power, see the relevant description with reference to FIG. 7. If the received power control bit transmitted from the base station, the mobile station gradually increases the transmission power by deciding that the base station has not received the power control bit transmitted from the mobile station. The mobile station increases the transmission power little by little in an interval between T0 and T1. Deciding a power control bit transmitted from the mobile station at the time T2, the base station measures the power of the received power control bit and generating power control bit to control transmission power of the mobile station and transmits the power control bit with a transmission power adjusted in accordance with the control bit power received from the mobile station. In the interval between time T2, when the base station receives the power control bit transmitted from the mobile station and T1, when the mobile station receives the power control bit transmitted from the base station, the base station and the mobile station may gradually increase the transmission power. Referring to FIG. 12A, that the base station receives the power control bit transmitted from the mobile station, in the interval T2, meaning that the received power of the power control bit from the mobile station is located at approximately the same level as the received power of signals transmitted by other mobile stations. However, in the time interval between T1 and T2, the mobile station is unable to accept the power control bit transmitted from the base station continuously increases the transmission power. As soon as the time interval between T2 and T1 increases camping, the received power of the power control bit received from the mobile station is significantly higher than the received power of signals received from other mobile stations, which have a negative effect on overall system performance. To minimize the interval between T2 and T1, it is preferable that in the slotted substate, having power control bit dedicated mobile station, the base station power control bit transmitted with the maximum transmit power. Once the mobile station receives the power control bit transmitted from the base station at time T1, the base station and the mobile station adjust the transmission power according to the power control bits received from the other party. Sensing that the other party controls the transmission power according to the power level of the received power control bit, the base station and the mobile station exchange a state transition message and an ACK signal to make a transition to the normal substate by deciding the completion of power level arbitration.

The base station in the slotted substate, initiates the power level arbitration to transmit data to FIG. 12B, when the base station has data to be transmitted to a base station in the slotted substate, the base station transmits to the mobile station the power control bit with the purpose of power level arbitration. Initial transmission power control bit: power set to the proper level, or equal to the maximum base station transmission power. As for a more complete description of the initial transmission power level, refer to relevant description given with reference to FIG. 7. If the received power control bit transmitted from the mobile station, the base station increases the transmission power little by deciding that the mobile station has not received the power control bit transmitted from the base station. The base station gradually increases the transmission power in the time interval between T0 and T2. Deciding a power control bit transmitted from the base station at time T1, the mobile station generates a power control bit for controlling transmission power of a base station in accordance with the level of the received power control bit power, starting with a sufficiently low initial transmission power, and transmits to the base station power control bit with the controlled transmission power. In the interval between time T1, when the mobile station receives the power control bit transmitted from the base station, and T2, when the base station receives the power control bit transmitted from the mobile station, the base station and the mobile station is gradually increased and the corresponding transmission power. Once the base station receives the power control bit transmitted from the mobile station at the time T2, the base station and the mobile station adjust the transmission power according to the power control bits received from the other party. Feeling that the other party controls the transmission power of the other party in accordance with the level of the received power of the power control bit, the base station and the mobile station exchange messages about the transition states and the ACK signal to make a transition to the normal substate, decided to complete the arbitration process power level.

Referring to FIG. 12A and 12B, since the power level arbitration performed when there is data to transmit, a transition to the active state occurs immediately after the transition to the normal substate.

The signal at the power level arbitration FIG. 13A and 13B are diagrams illustrating signaling messages transmitted via the pilot channel and the uplink dedicated control channel in the forward link power level during arbitration. On the reverse link power control bit (PCB) is transmitted over the pilot channel, as shown in FIG. 13A; on the forward link power control bit is transmitted over a dedicated control channel, as shown in FIG. 13B. Referring to FIG. 13A, preamble signals WS makes possible the implementation of data acquisition and channel estimation. Therefore, in the above example, the base station also generates power control bit corresponding to the received preamble signals and power control signals. According to an embodiment, preamble signals transmit information known to both the base station and the mobile station. The information known to both the base station and mobile station can be a bit stream consisting of all "0" or all "1".

Operation power level arbitration method of FIG. 14 and 15 are block diagrams illustrating the power level arbitration is regular, carried respectively by the base station and the mobile station.

Referring to FIG. 14, in the normal substate (Step 100), the base station checks the data to be transmitted (step 102). When there is data to transmit, a transition to the active state to transmit the data (step 104). However, there is no data to transmit, the base station waits a predetermined time (step 106). Here, the predetermined time is a maximum holding time of the normal substate. When the predetermine time has not elapsed, the normal substate is maintained, otherwise, a transition to the slotted substate (Step 108). In the slotted substate, the base station determines whether it is time to produce the power level arbitration (step 112). In step procedure call (not indicated) Sun and MS negotiate power level arbitration time. Until the time comes to perform the power level arbitration is supported slotted substate. Otherwise, upon the occurrence of the power level arbitration time, the base station transmits the power control bit (Step 114). After transmitting the power control bit, the base station determines whether the mobile station from the power control bit. The base station can not receive the power control bit transmitted from the mobile station, if the power control signal transmitted by the mobile station is equal to or below the threshold power PM is a mobile station. The threshold power PM is a power level at which the base station can detect a received signal after demodulation. If the received power control bit power transmitted by the mobile station is equal to or below the threshold power PM, the base station increases the transmission power to transmit the power control bit with the increased transmission power, deciding that the mobile station has not received the power control bit transmitted from the base station (Steps 116 and 118). However, if the received power control bit power transmitted by the mobile station, above the threshold power PM, the base station controls the transmission power according to the power level of the received power control bit and transmits the power control bit with the controlled transmission power (Steps 116 and 120). After transmitting the power control bit, the base station determines whether the received power is changing the power control bit transmitted by a mobile station in accordance with the power control bit which is transmitted from the base station (step 122). In the absence of any changes in the level of the received power control bit power transmitted by the mobile station, the base station increases again the transmission power to transmit the power control bit with the increased transmission power operations 122 and 118. Changing the transmission power of the mobile station identifies the base station that the mobile station It took the power control bit transmitted from the base station. Therefore, to detect a change of transmit power of the mobile station, the base station makes a transition to the normal substate in any of the above methods to transmit the data, taking the arbitration is completed power level (operations 122 and 124).

Referring to FIG. 14, the power level arbitration performed at a scheduled time regardless of whether data to be transmitted. Therefore, when there is data to transmit, a transition to the active state (Steps 126, 128 and 130). Otherwise, there is no data to transmit, a transition back to the slotted substate (Steps 126 and 108).

Referring to FIG. 15, in the normal substate, the mobile station checks the data to transmit (Steps 200 and 202). When there is data to transmit, a transition to the active state to transmit the data (step 204). However, there is no data to transmit, the mobile station waits a predetermined time (step 206). Here, the predetermined time is a maximum holding time of the normal substate. When the predetermine time has not elapsed, the normal substate is maintained, otherwise, a transition to the slotted substate (Step 208). In the slotted substate, the mobile station determines whether it is time to make arbitration power level (step 212). Until the time comes to perform the power level arbitration is supported slotted substate. Otherwise, if it is time to power level arbitration, the mobile station transmits the power control bit (Step 214). After transmitting the power control bit, the mobile station determines whether the base station from the power control bit. The mobile station can not receive the power control bit transmitted from the base station, if the power control signal transmitted from the base station is equal to or below the threshold power, RB base station. RB threshold power is the power level at which the mobile station can detect a received signal after demodulation. If the received power is the power control bit transmitted from the base station is equal to or below the threshold power RB, the mobile station increases the transmission power to transmit the power control bit with the increased transmission power, by deciding that the base station has not received the power control bit transmitted from the mobile station ( operations 216 and 218). However, if the received power of the power control bit transmitted from the base station is above a threshold power RB, the mobile station generates a control bit power reduction to control transmission power of a base station in accordance with the received power control bit and transmits the power control bit with the controlled transmission power ( operations 216 and 220). After transmitting the power control bit, the mobile station determines whether the received power is changing the power control bit transmitted from the base station, in accordance with the power control bit, which was previously transmitted to the mobile station (step 222). In the absence of any change of the received power control bit power transmitted from the base station, the mobile station increases again the transmission power to transmit the power control bit with the increased transmission power (Steps 222 and 218). Changing the base station transmission power mobile station indicates that the base station has received the power control bit transmitted from the mobile station. Therefore, finding a change of transmit power of the base station, the mobile station makes a transition to the normal substate in any of the methods described above to transmit the data, in deciding a power level arbitration is completed (Steps 222 and 224).

Referring to FIG. 15, the power level arbitration performed at a scheduled time regardless of whether data to be transmitted. Therefore, when there is data to transmit, a transition to the active state (Steps 226, 228 and 230). Otherwise, there is no data to transmit, a transition back to the slotted substate (Steps 226 and 208).

II. Irregular power level arbitration (AUM) FIG. 16 and 17 are block diagrams illustrating the power level arbitration is irregular, carried respectively by the base station and the mobile station, particularly, to FIG. 16 shows the case where the base station in the slotted substate, power level arbitration requests to transmit data when there is data to be transmitted; FIG. 17 shows the case where the mobile station in the slotted substate, power level arbitration requests for the transmission of data when there is data to transmit.

(IIa) Base Station initiates irregular AUM Referring to FIG. 16, in the normal substate, the base station checks the data to transmit (Steps 300 and 302). When there is data to transmit, a transition to the active state to transmit the data (step 304). However, there is no data to transmit, the base station waits a predetermined time (step 306). Here, the predetermined time is a maximum holding time of the normal substate. When the predetermine time has not elapsed, the normal substate is maintained, otherwise, a transition to the slotted substate (Step 308). In the slotted substate, the base station determines whether there is data to be transmitted / received (step 312). The case of there is data to transmit / receive corresponds to the case where the base station requests the power level arbitration. On the contrary, in case of absence of data to transmit / receive corresponds to the case where the mobile station requests the power level arbitration.

If the slotted substate (Step 310) is no data to be transmitted / received, the base station determines whether the mobile station transmitted power control bit (Steps 312 and 313). If it is judged that the mobile station transmits the power control bit, the base station compares the transmission power of the mobile station with a threshold power, PM, of the mobile station. If it is judged that the mobile station has transmitted the power control bit, the base station controls the transmission power according to the power control bit transmitted from the mobile station and transmits the power control bit with the controlled transmission power (Steps 313 and 320). After transmitting the power control bit, the base station determines whether the mobile station has changed the transmission power according to the power control bit transmitted by the base station (step 322). In the absence of any change transmission power of the mobile station, the base station increases again the transmission power to transmit the power control bit with the increased transmission power (Steps 322 and 318). Detect changes transmission power of the mobile station, the base station makes a transition to the normal substate in any of the above methods to transmit the data, taking the arbitration is completed power level (operations 322, 324 and 326). Referring to FIG. 16, the power level arbitration is performed because of the presence of data to be transmitted. Therefore, the base station makes a direct transition to the active state (Steps 328 and 330).

Meanwhile, when there is data to transmit / receive in the slotted substate, the base station transmits the power control bit (Steps 312 and 314). After transmitting the power control bit, the base station determines whether the mobile station from the power control bit (Step 316). If unable to receive from the mobile station power control bit, the base station increases the transmission power to transmit the power control bit with the increased transmission power, deciding that the mobile station has not received the power control bit transmitted from the base station (step 318). However, by adopting the mobile station power control bit, the base station controls the transmission power according to the power control bit received from the mobile station and transmits the power control bit with the controlled transmission power (Step 320). Thereafter, the base station determines whether the mobile station has changed the transmission power according to the power control bit transmitted by the base station (step 322). In the absence of any changes in the level of transmit power of the mobile station, the base station increases again the transmission power to transmit the power control bit with the increased transmission power (Steps 322 and 318). Detect changes transmission power of the mobile station, the base station makes a transition to the normal substate in any of the above methods to transmit the data, taking the arbitration is completed power level (operations 322, 324 and 326). Referring to FIG. 16, the power level arbitration is performed because of the presence of data to be transmitted. Therefore, the base station makes a direct transition to the active state (Steps 328 and 330).

(IIb) The mobile station initiates an irregular AUM According to FIG. 17, in the normal substate, the mobile station checks the data to transmit (Steps 400 and 402). When there is data to transmit, a transition to the active state to transmit the data (step 404). However, there is no data to transmit, the mobile station waits a predetermined time (step 406). Here, the predetermined time is a maximum holding time of the normal polsostoyaniya. When the predetermine time has not elapsed, the normal substate is maintained, otherwise, a transition to the slotted substate (Step 408). In the slotted substate, the mobile station determines whether there is data to be transmitted / received (step 412). The case of there is data to transmit / receive corresponds to the case where the mobile station requests the power level arbitration.

If the slotted substate (Step 410), no data to be transmitted / received, the mobile station determines whether the base station transmitted power control bit (Steps 412 and 413). If it is judged that the base station transmits the power control bit, the mobile station maintains the slotted substate. To determine whether the base station transmitted power control bit, the mobile station compares the transmission power of the base station with a threshold power, RB base station. If it is judged that the base station transmitted power control bit, the mobile station adjusts transmission power in accordance with the power control bit transmitted by the base station when transmits the power control bit (Steps 413 and 420). After transmitting the power control bit, the mobile station determines whether the base station has changed the transmission power according to the power control bit transmitted from the mobile station (step 422). In the absence of any changes in the level of transmit power of the base station, the mobile station increases again the transmission power to transmit the power control bit with the increased transmission power (Steps 422 and 418). Detect changes transmission power of the base station, the mobile station makes a transition to the normal substate in any of vyscheopisannyh ways to transmit the data, taking the arbitration is completed power level (operations 422, 424 and 426). According to Figure 17, the power level arbitration is performed because of the presence of data to be transmitted. Therefore, the mobile station makes a direct transition to the active state (Steps 428 and 430).

Meanwhile, when there is data to transmit / receive in the slotted substate, the mobile station transmits the power control bit (Steps 412 and 414). After transmitting the power control bit, the mobile station determines whether the base station from the power control bit (Step 416). If unable to receive from the base station the power control bit, the mobile station increases the transmission power to transmit the power control bit with the increased transmission power, by deciding that the base station has not received the power control bit transmitted from the mobile station (step 418). However, by adopting the base station power control bit, the mobile station controls the transmission power according to the power control bit received from the base station and transmits the power control bit with the controlled transmission power (Step 420). Thereafter, the mobile station determines whether the base station has changed the transmission power according to the power control bit transmitted from the mobile station (step 422). In the absence of any changes in the level of transmit power of the base station, the mobile station increases again the transmission power to transmit the power control bit with the increased transmission power (Steps 422 and 418). Detect a change of transmit power of the base station, the mobile station makes a transition to the normal substate in any of the methods described above to transmit the data, in deciding a power level arbitration is completed (Steps 422, 424 and 426). Referring to FIG. 17, the power level arbitration is performed because of the presence of data to be transmitted. Therefore, the mobile station makes a direct transition to the active state (Steps 428 and 430).

In light of the foregoing, the new CDMA mobile communication system can make a quick transition from the control hold state to the active state when there is data to transmit. Although the invention has been shown and described with reference to a certain preferred embodiment thereof, those skilled will be understood that it is susceptible to various changes in form and detail without departing however from the scope and spirit of the invention as defined by the appended claims.