Mobile station, base station and method of controlling measurement of peripheral cell

The present invention relates to a mobile station device, a base station device, and a peripheral cell measurement control method.

In the cellular system, handover control is performed to appropriately switch the connected cells (base station devices) as the user moves. In the handover control, in order to hand over to an appropriate adjacent cell, the propagation status of peripheral cells is measured in the mobile station apparatus, and the handover is performed based on the measurement result.

Here, in the peripheral cell and the connected own cell, a frequency carrier different from the frequency carrier currently used for communication, that is, a different frequency may be operated, or a plurality of frequency carriers are operated. In some cases. When attempting to hand over to these different frequencies, it is necessary to measure the propagation status of different frequencies of the peripheral cell or the own cell in the mobile station device.

In addition, there are cases where cells using different wireless systems (different systems) exist in the surroundings, and it is possible to sustain communication more advantageously from the viewpoint of traffic volume and propagation status by handing over to these cells. In such a situation, it becomes necessary to measure different frequencies and different systems during communication in the mobile station device.

It should be noted here that a mobile station device having only a single receiver cannot measure a plurality of frequencies and systems at the same time.

This is mainly because the RF (Radio Frequency) circuit of the receiver cannot be tuned to multiple frequency carriers or systems at the same time. When trying to measure multiple frequency carriers and systems at the same time, it is necessary to have multiple receivers (RF circuits), which increases the size, power consumption, and price of mobile station equipment.

Therefore, many mobile station devices in use today consist of a single receiver. When trying to measure different frequencies or different systems in such a mobile station device, the current communication is switched to intermittent reception (DRX), and the measurement is performed using the generated gap time. .. In this case, if the base station device does not know the DRX gap, the mobile station device will transmit the signal during the period during which the measurement cannot be received. Such transmission not only wastes valuable radio resources, but may also have adverse effects such as increasing interference power with other communications and increasing delay. In order to avoid such transmission, it is necessary to grasp the DRX state of the mobile station device also in the base station device.

Here, in a wireless system such as HSDPA, in order to perform link adaptation following high-speed fading, for example, transmission power control and AMC (Adaptive Modulation and Coding), the mobile station device sends the wireless channel status to the base station device (hereinafter referred to as the following). , Channel Quality Indicator (CQI)) is frequently reported. For example, in HSDPA, the E of the common pilot channel transmitted from the base station device in the mobile station device._c/ I₀(Received chip energy to interference power ratio) is measured, and the value obtained by quantizing this into 32 values is reported as CQI with a period of 2 ms (or an integral multiple of that period).

<p> However, the above-mentioned background technology has the following problems.</p><p> In the wireless communication system as described above, the DRX is controlled by a wireless protocol, for example, the Radio Resource Control (RRC) protocol in WCDMA.</p><p> However, such control consumes valuable radio resources and has a problem of reducing the originally intended communication capacity.</p><p> In addition, if the control command is logically incorrect, the mobile station device or base station device may malfunction.</p><p> Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is a mobile station device and a base capable of controlling intermittent reception / intermittent transmission while reducing the consumption of radio resources. It is an object of the present invention to provide a local apparatus and a peripheral cell measurement control method.</p>

<p> With this configuration, it is possible to autonomously switch to the measurement mode for measuring different frequencies and different systems based on the averaged radio channel state.</p><p> With this configuration, it is possible to autonomously switch to the intermittent transmission mode in which intermittent transmission is performed based on the averaged radio channel state.</p><p> By doing so, it is possible to autonomously switch to the measurement mode for measuring different frequencies and different systems based on the averaged radio channel state.</p><p><u style="single">Book transfer</u>The motivation device is Radio channel condition measuring means for measuring radio channel condition; Sorting means for determining the cumulative density distribution of measured radio channel states;<u style="single">A first statistic calculation means for calculating a first statistic that switches to a measurement mode for measuring a different system based on the cumulative density distribution;</u><u style="single">A reception mode control means that compares the first statistic with a predetermined threshold value and switches to a measurement mode for measuring a different system when the first statistic is equal to or less than the threshold value.</u> With<u style="single">To.</u></p><p> With this configuration, it is possible to autonomously switch to the measurement mode for measuring different frequencies and different systems based on the statistics obtained from the cumulative density distribution of the radio channel state.</p><p><u style="single">Main group</u>The local equipment is<u style="single">A base station device that communicates with the mobile station device.</u> Sorting means for obtaining the cumulative density distribution of the radio channel state notified from the mobile station device;<u style="single">A first statistic calculation means for calculating a first statistic for switching to the intermittent transmission mode based on the cumulative density distribution;</u><u style="single">The first statistic is compared with a predetermined threshold value, and when the first statistic is equal to or less than the threshold value, the mode is switched to the intermittent transmission mode.</u>Transmission mode control means; With<u style="single">To.</u></p><p> With this configuration, it is possible to autonomously switch to the intermittent transmission mode in which intermittent transmission is performed based on the statistic obtained from the cumulative density distribution of the radio channel state.</p><p><u style="single">This week</u>The edge cell measurement control method is Receiving step to receive common pilot channel transmitted from base station equipment covering area cells; Radio channel state measurement step of measuring radio channel state from the common pilot channel; Sort step to find the cumulative density distribution of the measured radio channel state;<u style="single">First statistic calculation step to calculate the first statistic to switch to the measurement mode to measure different systems based on the cumulative density distribution;</u><u style="single"> The first statistic is compared with a predetermined threshold value, and when the first statistic is equal to or less than the threshold value, the measurement mode is switched to measure a different system.</u>Receive mode control step; Have.</p><p> By doing so, it is possible to autonomously switch to the measurement mode for measuring different frequencies and different systems based on the statistics obtained from the cumulative density distribution of the radio channel state.</p>

<p> According to the embodiment of the present invention, it is possible to realize a mobile station device, a base station device, and a peripheral cell measurement control method capable of controlling intermittent reception / intermittent transmission while reducing the consumption of radio resources.</p>

Next, the best mode for carrying out the present invention will be described with reference to the drawings based on the following examples. In all the drawings for explaining the examples, those having the same function use the same reference numerals, and the repeated description will be omitted.

The wireless communication system according to the embodiment of the present invention includes a base station device and a mobile station device.

In the mobile communication system according to the present embodiment, the mobile station apparatus measures the radio channel state and averages the measured radio channel state for a predetermined period of time. In the mobile communication system, as shown in Fig. 1, when the average value of CQI (mean CQI) falls below a certain threshold value (system parameter), it becomes a mode (hereinafter referred to as measurement mode) in which different frequencies and different systems are measured. When the average CQI exceeds the same threshold value, the normal mode is restored.

In the measurement mode, the mobile station device compares the instantaneous value of CQI (instantaneous CQI) with the average CQI, and autonomously measures different frequencies and different systems by DRX while the instantaneous CQI is below the average CQI. .. Further, in the measurement mode, the mobile station apparatus makes it possible to receive data by tuning the receiver to the system / frequency currently used for communication without performing DRX during the period when the instantaneous CQI exceeds the average CQI.

For example, as shown in FIG. 2, in the measurement mode, when the instantaneous CQI is lower than the average CQI, the mobile station device performs DRX to measure different frequencies and different systems. This means tuning the receiver to a different frequency / system. Here, if the receiver is tuned to a different frequency / different system, CQI cannot be measured. Therefore, in order to measure CQI, it is necessary to periodically tune the receiver to the system frequency currently used for communication. For example, as shown in Fig. 2, the tuning system frequency is controlled in a short predetermined cycle.

Here, the case where the threshold value from the normal mode to the measurement mode and the threshold value from the measurement mode to the normal mode are the same value has been described, but the threshold value from the measurement mode to the normal mode may be different by giving hysteresis. Good.

Next, the mobile station apparatus 100 according to the embodiment of the present invention will be described with reference to FIG.

The mobile station device 100 according to this embodiment is a mobile station device that can be tuned to a plurality of systems by switching, and is a value obtained by averaging CQI for a certain period of time, for example, a period of time that can follow shadowing, for example, about several seconds (hereinafter). , Average CQI) is calculated, DRX is performed for the period when the instantaneous CQI is lower than this average CQI, and peripheral cells such as different frequencies and different systems are measured.

The mobile station device 100 inputs the antenna 102, the transmission / reception common unit 104 connected to the antenna 102, the reception RF unit 106 to which the reception signal from the transmission / reception common unit 104 is input, and the output signal from the reception RF unit 106. Peripheral cell measuring unit 118 and CQI measuring unit 108 as radio channel state measuring means, and CQI averaging unit 110 and CQI as radio channel state averaging means to which CQI information output from CQI measuring unit 108 is input. Output signals from the determination unit 116 and the multiple synthesis unit 124, the reception mode control unit 112 as a reception mode control means to which the output signal from the CQI averaging unit 110 is input, and the reception mode control unit 112 and the CQI determination unit 116. Is input to the DRX control unit 114 as an intermittent reception control means, the handover (HO) determination unit 120 to which the output signal from the peripheral cell measurement unit 118 is input, and the output signal from the HO determination unit 120. It includes an HO signal generation unit 122 and a transmission RF unit 126 to which an output signal from the multiplex synthesis unit 124 is input.

The output signal of the CQI averaging unit 110 is input to the CQI determination unit 116. Further, the output signal of the DRX control unit 114 is input to the reception RF unit 106 and the peripheral cell measurement unit 118. Further, the HO command output from the HO signal generation unit 122 is input to the multiplex synthesis unit 124, and the output signal of the transmission RF unit 126 is input to the transmission / reception common unit 104.

The reception RF unit 106 receives a signal in synchronization with the system frequency to be received, and inputs the received data to the CQI measurement unit 108 and the peripheral cell measurement unit 118. For example, the receiving RF unit 106 tunes to the frequency / radio system (system) currently used for communication in the normal mode. Further, for example, the receiving RF unit 106 tunes to the frequency / system of the peripheral cell during DRX in the measurement mode.

However, as explained with reference to FIG. 2, the receiving RF unit 106 is currently used for communication at the timing of measuring CQI even during DRX, for example, at the timing of receiving the common pilot channel of the cell being communicated. Synchronize with the frequency and system you are using.

The CQI measuring unit 108 measures the radio channel state (CQI) from the received signal of the cell currently communicating, for example, the common pilot channel, and outputs the information indicating the instantaneous value of the CQI to the CQI averaging unit 110, the CQI determining unit 116, and the multiplexing. Input to the synthesis unit 124.

The CQI averaging unit 110 averages the CQI and inputs information indicating the average CQI to the reception mode control unit 112 and the CQI determination unit 116. For example, the CQI averaging unit 110 smoothes high-speed fading and averages the CQI to the extent that it can follow shadowing.

The CQI determination unit 116 compares and determines the instantaneous value and the average value of the CQI, and inputs the result to the DRX control unit 114.

The reception mode control unit 112 compares the average CQI with the threshold value and controls the reception mode. That is, the reception mode control unit 112 controls switching between the measurement mode and the normal mode based on the average CQI. Further, the reception mode control unit 112 inputs information indicating the reception mode to the DRX control unit 114.

When information indicating the measurement mode is input from the reception mode control unit 112, the DRX control unit 114 controls the tuning frequency / system of the reception RF unit 106 based on the comparison result input by the CQI determination unit 116. For example, the DRX control unit 114 controls to tune to the frequency / system currently used for communication when information indicating that the instantaneous value of CQI is larger than the average CQI is input. Further, for example, the DRX control unit 114 controls to tune to a different system frequency to be measured, for example, a frequency system of a peripheral cell when information indicating that the instantaneous value of CQI is smaller than the average CQI is input. To do.

Further, the DRX control unit 114 controls the measurement start and stop of the peripheral cell in the peripheral cell measurement unit 118.

The DRX control unit 114 pauses when information indicating the normal mode is input from the reception mode control unit 112.

In the measurement mode, the peripheral cell measuring unit 118 measures the propagation status of peripheral cells such as during DRX, different frequencies, and different systems based on the control of the DRX control unit 114. For example, the peripheral cell measuring unit 118 measures the propagation status of the peripheral cells based on the received data input by the receiving RF unit 106, and inputs the information indicating the propagation status to the HO determination unit 120. The peripheral cell measuring unit 118 pauses in the normal mode.

In the measurement mode, the HO determination unit 120 determines the necessity of handover (HO) according to the measurement result of the propagation status of the peripheral cell measured by the peripheral cell measurement unit 118, and generates an HO signal based on the determination result. Enter in part 122. The HO determination unit 120 pauses in the normal mode.

The HO signal generation unit 122 generates a control command for executing the HO when the HO determination unit 120 determines that the HO is necessary, and inputs the HO command to the multiplex synthesis unit 124. The HO signal generator 122 pauses in the normal mode.

The multiplex synthesis unit 124 multiplexes the CQI report value (instantaneous CQI), the HO control signal, and the uplink user data, and inputs them to the transmission RF unit 126.

The transmission RF unit 126 converts the transmission signal into an RF signal and excites the antenna. As a result, the data is transmitted.

Next, the base station apparatus according to the embodiment of the present invention will be described with reference to FIG.

The base station apparatus 200 according to this embodiment has two transmission modes, that is, a normal mode and an intermittent transmission mode, corresponding to the reception mode described above. The intermittent transmission mode corresponds to the measurement mode in the mobile station apparatus 100.

The base station apparatus 200 averages the radio channel state (CQI) reported from the mobile station apparatus 100 by the same algorithm as that of the mobile station apparatus 100, and switches to the intermittent transmission mode in which intermittent transmission is performed based on the average value of CQI. .. That is, the base station apparatus 200 performs the above-mentioned DRX / DTX control when the average CQI falls below a certain threshold value, ends the DRX / DTX control when the average CQI exceeds a certain threshold value, and returns to the normal communication mode. Return.

Further, in the intermittent transmission mode, the base station apparatus 200 determines that the mobile station apparatus is performing DRX when the reported instantaneous CQI is lower than the average value of the CQI, and the downlink signal addressed to the mobile station apparatus. That is, Discontinuous Transmission (DTX) is performed.

The base station apparatus 200 according to this embodiment is described by the antenna 202, the transmission / reception common unit 204 connected to the antenna 202, the reception RF unit 206 into which the reception signal from the transmission / reception common unit 204 is input, and the reception RF unit 206. From the multiple separation unit 208 to which the output signal of the above is input, the CQI determination unit 216 to which the CQI information is input from the multiple separation unit 208, the CQI averaging unit 210 as the radio channel state averaging means, and the CQI averaging unit 210. The transmission mode control unit 212 as the transmission mode control means to which the output signal of the above is input, and the DTX control unit 214 as the intermittent transmission control unit to which the output signals from the transmission mode control unit 212 and the CQI determination unit 216 are input. The transmission signal generation unit 218 to which the output signal from the DTX control unit 214 is input, the multiplex synthesis unit 220 to which the output signal from the transmission signal generation unit 218 is input, and the output signal from the multiplex synthesis unit 220 are input. A transmission RF unit 222 is provided.

The output signal of the CQI averaging unit 210 is input to the CQI determination unit 216. Further, the output signal of the transmission RF unit 222 is input to the transmission / reception common unit 204.

The reception RF unit 206 receives the signal in synchronization with the uplink signal from the mobile station device 100, and inputs the received data to the multiplex separation unit 208. The received data stores, for example, CQI information, uplink user data, other user data, control signals, and the like.

The multiplex separation unit 208 extracts CQI information from the received signal and inputs the CQI information to the CQI averaging unit 210 and the CQI determination unit 216.

The CQI averaging unit 210 performs CQI averaging processing by the same averaging method as the averaging unit 110 of the mobile station apparatus 100, and transmits information indicating the averaged CQI (average CQI) to the transmission mode control unit 212. And input to CQI judgment unit 216.

The CQI determination unit 216 compares and determines the CQI (instantaneous CQI) input by the multiplex separation unit 208 and the CQI (average CQI) input by the CQI averaging unit 210, and inputs the result to the DTX control unit 214. To do.

The transmission mode control unit 212 controls the transmission mode by comparing the average CQI input by the CQI averaging unit 210 with a predetermined threshold value. For example, the transmission mode control unit 212 controls to switch between the normal mode and the intermittent transmission mode based on the comparison result between the average CQI and a predetermined threshold value. Further, the transmission mode control unit 212 inputs information indicating the transmission mode to the DTX control unit 214.

The DTX control unit 214 controls the transmission of data according to the comparison result input by the CQI determination unit 216 when the information indicating the transmission mode input from the transmission mode control unit 212 is the intermittent transmission mode. For example, in the intermittent transmission mode, if the instantaneous CQI is smaller than the average CQI, the DTX control unit 214 determines that the mobile station device 100 is performing DRX, and transmits a downlink signal to the mobile station device 100. Perform DTX control to stop. Further, the DTX control unit 214 controls to continue communication when the instantaneous CQI is larger than the average CQI in the intermittent transmission mode. The DTX control unit 214 inputs information indicating the DTX control state to the transmission signal generation unit 218.

The transmission signal generation unit 218 generates a downlink signal of the user to be controlled based on the input downlink user data, and inputs it to the multiplex synthesis unit 220.

The multiplex synthesis unit 220 multiplexes the downlink signal with the downlink signal or control signal of another user to be transmitted at the same time, and inputs the downlink signal to the transmission RF unit 222.

The transmission RF unit 222 converts the transmission signal into RF to excite the antenna. As a result, the data is transmitted.

Next, the operation of the mobile station apparatus 100 according to this embodiment will be described with reference to FIG.

The CQI measuring unit 108 measures the radio channel state (CQI) from the received signal of the cell currently communicating, for example, the common pilot channel (step S502).

Next, the CQI averaging unit 110 averages the CQI (step S504).

Next, the reception mode control unit 112 compares the average CQI with the threshold value (step S506).

When the average CQI is below the threshold value, that is, when the average CQI threshold value is not satisfied (step S506: NO), the reception mode control unit 112 sets the communication mode (step S508). Then, the process returns to step S502.

On the other hand, when the average CQI threshold value (step S506: YES), the reception mode control unit 112 sets the measurement mode (step S510).

Next, the CQI determination unit 116 compares and determines the instantaneous value (instantaneous CQI) of the CQI and the average value (average CQI) (step S512).

When the instantaneous CQI is equal to or less than the average CQI, that is, when the instantaneous CQI the average CQI (step S512: YES), the DRX control unit 114 performs DRX and controls to measure different frequencies and different systems (step S514). Then, the process returns to step S502.

On the other hand, when the instantaneous CQI the average CQI is not satisfied (step S512: NO), the DRX control unit 114 controls to continue the communication (step S516). Then, the process returns to step S502.

Under ideal operation, switching between normal mode / measurement mode of mobile station device 100 and base station device 200, and DRX timing and DTX timing in measurement mode are perfectly synchronized.

According to the wireless system according to this embodiment, the DRX / DTX can be accurately and autonomously controlled without being controlled by a wireless protocol such as RRC. It is possible to avoid the consumption of radio resources due to the radio protocol signal conventionally required for DRX / DTX control.

Next, the wireless communication system according to another embodiment of the present invention will be described.

Since the configuration of the wireless communication system according to this embodiment is the same as the configuration of the wireless communication system described above, the description thereof will be omitted.

The basic operation of the wireless communication system according to this embodiment is the same as the operation of the wireless communication system described above. For example, the wireless communication system according to the present embodiment switches between the measurement mode / the normal mode and performs DTX / DRX control in the measurement mode, similarly to the wireless communication system described above.

In the wireless communication system according to this embodiment, the value used for determining the measurement mode / normal mode switching control is not the average value of CQI but the statistic obtained from the cumulative density distribution of CQI. It is different from the wireless communication system related to.

In the wireless communication system according to this embodiment, the mobile station apparatus acquires the measured cumulative density distribution (CDF: Cumulative Distribution Function) of CQI.

Then, as shown in FIG. 6, the mobile station apparatus has a predetermined percentage value of CQI, for example, an X percentage value as a second statistic and a Y percentage value as a first statistic (hereinafter, CQI)._X, CQI_YCQI to switch between measurement mode / normal mode_YDTX / DRX control in measurement mode based on CQI_XDo based on. Here, the magnitude relationship between X and Y is arbitrary.

For example, in the mobile communication system according to this embodiment, CQI is shown as shown in FIG._YWhen a certain threshold value (system parameter) is exceeded, the measurement mode is set to measure different frequencies and different systems, and CQI_YReturns to the normal mode when the value exceeds the same threshold value.

During the measurement mode, the mobile station device has the instantaneous value of CQI (instantaneous CQI) and CQI._XCompare with and the instant CQI is CQI_XDuring the period below, DRX is performed to autonomously measure different frequencies and different systems. Also, during the measurement mode, the mobile station device has an instantaneous CQI of CQI._XDuring the period exceeding the above, the receiver can be tuned to the system frequency currently used for communication without performing DRX so that data can be received.

For example, as shown in FIG. 8, in the measurement mode, the mobile station device has an instantaneous CQI of CQI._XIf it is below, perform DRX to measure different frequencies and different systems. This means tuning the receiver to a different frequency / system. Here, if the receiver is tuned to a different frequency / different system, CQI cannot be measured. Therefore, in order to measure CQI, it is necessary to periodically tune the receiver to the system frequency currently used for communication. For example, as shown in FIG. 8, the tuning system frequency is controlled in a short predetermined cycle.

Next, the mobile station apparatus 100 according to this embodiment will be described with reference to FIG.

In the mobile station apparatus described with reference to FIG. 3, the mobile station apparatus 100 according to this embodiment has a CQI register 128 to which an output signal of the CQI measuring unit 108 is input instead of the CQI averaging unit 110 and a CQI. It includes a CQI sort unit 130 to which the output signal of the register 128 is input, a CQI threshold value setting unit 132 to which the output signal of the CQI sort unit 130 is input, and a mode switching threshold value setting unit 134. The CQI threshold setting unit 132 sends the CQI to the CQI determination unit 116._XEnter. Further, the mode switching threshold value setting unit 134 informs the reception mode control unit 112 of CQI._YEnter.

The CQI register 128 stores the CQI. For example, the CQI register 128 is composed of a shift register and holds a CQI value for a certain period of time in the past, for example, for 3 seconds (hereinafter referred to as T). The CQI register 128 may discard the portion stored beyond T. The CQI register 128 may change T according to the moving speed of the mobile station apparatus 100. For example, the CQI register 128 decreases T when the mobile station device 100 is moving at high speed and increases T when the moving speed is low. Specifically, the CQI register 128 controls to decrease T when the moving speed of the mobile station device 100 is equal to or higher than a certain threshold value and to increase T when the moving speed is equal to or lower than a certain threshold value. Further, the mobile station device 100 notifies the base station device 200 of information indicating the moving speed.

The CQI sort unit 130 sorts the CQI values (CQI samples) held in the CQI register 128 in ascending (or descending) order, obtains the cumulative density distribution, and uses the cumulative density distribution as the CQI threshold setting unit 132 and the mode switching threshold. Input to the setting unit 134.

The CQI threshold setting unit 132 uses the CQI based on the cumulative density distribution input from the CQI sort unit 130._XCalculate the value of CQI_XIs input to the CQI determination unit 116. For example, the CQI threshold setting unit 132 applies interpolation calculation such as linear interpolation to CQI._XCalculate the value of.

The mode switching threshold setting unit 134 has a CQI based on the cumulative density distribution input from the CQI sort unit 130._YCalculate the value of CQI_YIs input to the reception mode control unit 112. For example, the mode switching threshold setting unit 134 applies interpolation calculation such as linear interpolation to CQI._YCalculate the value of.

The CQI determination unit 116 uses the instantaneous value of CQI and the CQI._XIs compared and determined, and the comparison result is input to the DRX control unit 114.

The reception mode control unit 112 is a CQI_YThe reception mode, that is, the switching between the measurement mode and the normal mode is controlled according to the above. For example, the reception mode control unit 112 compares the CQI with a certain threshold value (system parameter)._YIf it is above a certain threshold value, it switches to the normal mode, and if it is less than a certain threshold value, it switches to the measurement mode.

The DRX control unit 114 instantly CQI and CQI during the measurement mode._XBased on the comparison result with, the instantaneous CQI is CQI_XDuring the period below, DRX is controlled to autonomously measure different frequencies and different systems. In addition, the DRX control unit 114 instantaneously CQI and CQI during the measurement mode._XBased on the comparison result with, the instantaneous CQI is CQI_XDuring the period exceeding the above, DRX is not performed and the receiver is tuned to the system frequency currently used for communication to control so that data can be received.

Next, the base station apparatus 100 according to this embodiment will be described with reference to FIG.

In the base station apparatus described with reference to FIG. 4, the base station apparatus 200 according to the present embodiment has a CQI register 224 and a CQI register 224 in which the output signal of the multiplexing separation unit 208 is input instead of the CQI averaging unit 210. It includes a CQI sort unit 226 to which the output signal of the register 224 is input, a CQI threshold value setting unit 228 to which the output signal of the CQI sort unit 226 is input, and a mode switching threshold value setting unit 230. The CQI threshold setting unit 228 attaches the CQI to the CQI determination unit 216._XEnter. Further, the mode switching threshold value setting unit 230 connects the transmission mode control unit 212 to CQI._YEnter.

The CQI register 224 stores the CQI. For example, the CQI register 224 is composed of a shift register and holds a CQI value for a certain period of time in the past, for example, for 3 seconds (hereinafter referred to as T). The CQI register 224 may discard the portion stored beyond T. The CQI register 224 may change T according to the moving speed of the mobile station apparatus 100. For example, the CQI register 224 decreases T when the mobile station device 100 is moving at high speed and increases T when the moving speed is low. Specifically, the CQI register 224 controls to decrease T when the moving speed of the mobile station device 100 is equal to or higher than a certain threshold value and to increase T when the moving speed is equal to or lower than a certain threshold value. In this case, the mobile station device 100 notifies the information indicating the moving speed.

The CQI sort unit 226 sorts the CQI samples held in the CQI register 224 in ascending order (or descending order), obtains a cumulative density distribution, and transfers the cumulative density distribution to the CQI threshold value setting unit 228 and the mode switching threshold value setting unit 230. input.

The CQI threshold setting unit 228 uses the CQI based on the cumulative density distribution input from the CQI sort unit 226._XCalculate the value of CQI_XIs input to the CQI judgment unit 216. For example, the CQI threshold setting unit 228 applies interpolation calculation such as linear interpolation to CQI._XCalculate the value of.

The mode switching threshold setting unit 230 has a CQI based on the cumulative density distribution input from the CQI sort unit 226._YCalculate the value of CQI_YIs input to the transmission mode control unit 212. For example, the mode switching threshold setting unit 230 applies interpolation calculation such as linear interpolation to CQI._YCalculate the value of.

The CQI determination unit 216 uses the instantaneous value of CQI and the CQI._XIs compared and determined, and the comparison result is input to the DTX control unit 214.

The transmission mode control unit 212 is CQI_YThe transmission mode, that is, the switching between the intermittent transmission mode and the normal mode is controlled according to the above. For example, the transmission mode control unit 212 compares the CQI with a certain threshold value._YIf it is above a certain threshold value, it switches to the normal mode, and if it is less than a certain threshold value, it switches to the intermittent transmission mode.

The DTX control unit 214 controls the transmission of data according to the comparison result input by the CQI determination unit 216 when the information indicating the transmission mode input from the transmission mode control unit 212 is the intermittent transmission mode. For example, the DTX control unit 214 changes the instantaneous CQI to CQI when in the intermittent transmission mode._YIf it is smaller than that, it is determined that the mobile station apparatus 100 is performing DRX, and DTX control is performed to stop the transmission of the downlink signal addressed to the mobile station apparatus 100. In addition, the DTX control unit 214 changes the instantaneous CQI to CQI when in the intermittent transmission mode._YIf it is larger than that, control is performed to continue communication. The DTX control unit 214 inputs information indicating the DTX control state to the transmission signal generation unit 218.

Next, the operation of the mobile station apparatus 100 according to this embodiment will be described with reference to FIG.

The CQI measuring unit 108 measures the radio channel state (CQI) from the received signal of the cell currently communicating, for example, the common pilot channel (step S1102).

Next, the CQI register 128 stores the CQI value for a predetermined period (step S1104).

Next, the CQI sort unit 130 obtains the cumulative density distribution based on the CQI sample held in the CQI register 128 (step S1106).

Next, the CQI threshold setting unit 132 CQI based on the cumulative density distribution._XThe value of is calculated, and the mode switching threshold setting unit 134 CQI based on the cumulative density distribution._YCalculate the value of (step S1108).

Next, the reception mode control unit 112 sets the CQI._YAnd the threshold (step S1110).

CQI_YIs below the threshold, that is, CQI_YIf the threshold value is not set (step S1110: NO), the reception mode control unit 112 sets the communication mode (step S1112). Then, the process returns to step S1102.

Meanwhile, CQI_YWhen threshold value (step S1110: YES), the reception mode control unit 112 sets the measurement mode (step S1114).

Next, the CQI determination unit 116 uses the instantaneous value of CQI (instantaneous CQI) and CQI._XIs compared and judged (step S1116).

Instant CQI is CQI_XThe following, that is, instantaneous CQI CQI_XIf (step S1116: YES), the DRX control unit 114 performs DRX and controls to measure different frequencies and different systems (step S1118). Then, the process returns to step S1102.

On the other hand, instantaneous CQI CQI_XIf not (step S1116: NO), the DRX control unit 114 controls to continue communication (step S1120). Then, the process returns to step S1102.

Under ideal operation, switching between normal mode / measurement mode of mobile station equipment and base station equipment, and DRX timing and DTX timing in measurement mode are perfectly synchronized.

The mobile station device, the base station device, and the peripheral cell measurement control method according to the present invention can be applied to a wireless communication system.

<figref num="1">It is explanatory drawing which shows the operation of the wireless communication system which concerns on one Example of this invention.</figref><figref num="2">It is explanatory drawing which shows the operation of the wireless communication system which concerns on one Example of this invention.</figref><figref num="3">It is a partial block diagram which shows the mobile station apparatus which concerns on one Example of this invention.</figref><figref num="4">It is a partial block diagram which shows the base station apparatus which concerns on one Example of this invention.</figref><figref num="5">It is a flow figure which shows the operation of the mobile station apparatus which concerns on one Example of this invention.</figref><figref num="6">It is explanatory drawing which shows the cumulative density distribution of CQI.</figref><figref num="7">It is explanatory drawing which shows the operation of the wireless communication system which concerns on one Example of this invention.</figref><figref num="8">It is explanatory drawing which shows the operation of the wireless communication system which concerns on one Example of this invention.</figref><figref num="9">It is a partial block diagram which shows the mobile station apparatus which concerns on one Example of this invention.</figref><figref num="10">It is a partial block diagram which shows the base station apparatus which concerns on one Example of this invention.</figref><figref num="11">It is a flow figure which shows the operation of the mobile station apparatus which concerns on one Example of this invention.</figref>

Code description

100 mobile station equipment 200 base station equipment