Method for determining execution time of tight frequency-to-frequency switching of communication channel and for setting tight channel switching medium
Abstract
multiple access systems with code channel division. SUBSTANCE: time of execution and direction of switching in procedure of tight channel switching by base- station controller are determined for mobile station moving between two transceiver stations having different frequency distribution. . Servicing area of multiple access code-division system is divided into separate locations; each location has one or more sectors (sub-locations). The latter are, essentially, either general-frequency sub-locations or cutoff- frequency ones. General-frequency sub-locations are those using all general frequencies of adjacent sub-locations. Cutoff-frequency sub- locations are accordingly determined as those using not all general frequencies of adjacent locations. According to invention method involves following procedures: base-station controller receives message from mobile station about change in pilot-signal level; this message includes set of pilot-signals each being distinguished by pilot-signal level; after base-station controller has received this message all sub-locations with which mobile station can communicate at the time are checked to make sure that all of them are cutoff-frequency sub-locations; if it is found that at least one of them is other than cutoff-frequency sub- location, communication channel switching of general type is executed; if all sub-locations are found to be cutoff-frequency sub-locations, base- station controller periodically requests pilot-signal level change message from all sub-locations communicating with mobile station at present; message transmitted from mobile station in response to controller- initiated message request is analyzed to make sure that level of pilot- signals received from all sub-locations is not lower than preset definite power level T DOWN ; then timer preset to definite time T DOWN is invoked in case level of mentioned pilot-signals received from all sub- locations is below preset power level T DOWN; if timer completes reading without interruption within T DOWN interval, command is sent to mobile station for executing tight switching of communication channel inside location to general frequency serviced by all base transceiver stations. EFFECT: provision for tight frequency-to-frequency switching of communication channel. 14 cl, 4 dwg
Term
Term ended
Expired 11 June 2019, 7.3 years ago.
- Priority
- Filed
- Granted
- Expired
- Today
14 claims: 14 independent, 0 dependent
- 1Способ определения времени выполнения жесткого переключения канала связи с частоты на частоту в системе мобильной связи, разделенной на множество секторов, причем упомянутая система связи включает в себя по меньшей мере одну мобильную станцию, обеспечивающую абонента услугами мобильной связи, множество базовых приемопередающих станций (БПС), каждая из которых обслуживает один из упомянутого множества секторов и передает пилот-сигнал, идентифицирующий эту БПС, а также контроллер базовых станций, управляющий субъячейкой, включающий этапы, при которых:а) контроллер базовых станций (КБС) принимает от мобильной станции сообщение измерения уровня пилот-сигнала (СИУПС), причем СИУПС включает в себя множество пилот-сигналов, каждый из которых характеризуется уровнем пилот-сигнала;b) после того, как КБС принял СИУПС, определяют, являются ли все субъячейки, с которыми мобильная станция в настоящее время осуществляет связь, субъячейками пограничной частоты;с) если определено, что по меньшей мере одна субъячейка не является субъячейкой пограничной частоты, то выполняют гибкое переключение канала связи;d) если определено, что все субъячейки являются субъячейками пограничной частоты, то КБС периодически запрашивает СИУПС из всех субъячеек, с которыми мобильная станция в настоящее время осуществляет связь;е) анализирует принятое СИУПС, переданное от мобильной станции в ответ на запрос СИУПС от КБС, для определения того, не ниже ли уровень пилот-сигналов, принятых из всех субъячеек, чем предварительно определенный уровень мощности T_ DOWN, и если это так, то активизируют таймер, установленный на предварительно определенное время T_ DOWN;f) при нормальном истечении установленного времени отсчета таймера мобильной станции выдают команду выполнить жесткое переключение канала связи с частоты на частоту внутри ячейки на общую частоту, которая обслуживается всеми базовыми приемопередающими станциями.
- 2Способ по п. 1, отличающийся тем, что уровень мощности T_ DOWN устанавливают на более высокий уровень, чем пороговая величина T_ DROP сброса переключения канала связи.
- 3Способ по п. 2, отличающийся тем, что после этапа активизации таймера дополнительно включает этап отключения таймера и возвращения к этапу (d), если на этапе (е) определено, что уровни принятых пилот-сигналов всех субъячеек не меньше пороговой величины T_ DOWN.
- 4Способ по п. 3, отличающийся тем, что дополнительно включает этап возвращения к этапу (d), если на этапе (е) определено, что уровни принятых пилот-сигналов всех субъячеек меньше пороговой величины T_ DOWN.
- 5Способ по п. 1, отличающийся тем, дополнительно включает этап выполнения гибкого переключения канала связи, если в результате анализа запрошенного СИУПС определено, что для субъячейки общей частоты необходим дополнительный канал.
- 6Способ по п. 5, отличающийся тем, что дополнительно включает этап прекращения запроса СИУПС и отключения таймера.
- 7Способ по п. 5, отличающийся тем, что определение того, что для субъячейки общей частоты необходим дополнительный канал связи, основано на вновь принятом пилот-сигнале, связанном с субъячейкой общей частоты и принятом в качестве части периодического СИУПС.
- 8Способ по п. 1, отличающийся тем, что при определении на этапе анализа, что все субъячейки должны быть сброшены, способ дополнительно включает этап выполнения жесткого переключения канала связи с частоты на частоту внутри ячейки на общую частоту.
- 9Способ по п. 8, отличающийся тем, что определение того, что все ячейки должны быть сброшены, основано на том, что уровни пилот-сигналов, связанных со всеми субъячейками, ниже пороговой величины T_ DROP сброса переключения канала связи.
- 10Способ по п. 1, отличающийся тем, что этап активизации таймера включает дополнительные этапы, при которых определяют, не был ли уже активизирован таймер T_ ТDOWN, и возвращаются к этапу (d), если упомянутый таймер T_ ТDOWN уже был активизирован, в противном случае активизируют таймер T_ ТDOWN.
- 11Способ по п. 10, отличающийся тем, что этап активизации таймера дополнительно включает этап установления частоты, допускающей переключение, на общую частоту, причем общая частота представляет собой частоту, назначенную для выполнения жесткого переключения канала связи с частоты на частоту.
- 12Способ по п. 11, отличающийся тем, что общая частота сохраняется контроллером базовых станций в соответствии с устройством каждой базовой приемопередающей станции.
- 13Способ определения времени выполнения жесткого переключения канала связи с частоты на частоту в системе мобильной связи, которая включает в себя мобильную станцию, осуществляющую связь с множеством базовых станций, каждая базовая станция передает пилот-сигнал, идентифицирующий эту базовую станцию, множество базовых приемопередающих станций, каждая из которых обслуживает по меньшей мере один сектор, каждый из которых имеет собственный пилот-сигнал на соответствующей частоте, а также контроллер базовых станций, связывающий упомянутое множество базовых станций с центром коммутации мобильных станций и управляющий переключением канала связи мобильной станции, включающий этапы, при которых:а) устанавливают частоту, которую может обслуживать соседняя базовая приемопередающая станция, на общую частоту во всех субъячейках, которые могут быть обслужены в настоящее время, и устанавливают частоту, которую соседняя базовая приемопередающая станция не может обслуживать, на пограничную частоту во всех субъячейках, которые могут быть обслужены в настоящее время;b) определяют, не ниже ли уровень мощности пилот-сигналов всех субъячеек, чем пороговая величина T_ DOWN за непрерывный период времени по меньшей мере продолжительностью T_ ТDOWN, если определено, что все субъячейки, которые могут быть обслужены в настоящее время, являются субъячейками пограничной частоты;с) если определено, что уровень мощности пилот-сигналов всех субъячеек ниже пороговой величины T_ DOWN за непрерывный период времени по меньшей мере продолжительностью T_ ТDOWN, то мобильной станции выдают команду выполнить жесткое переключение канала связи с частоты на частоту для всех субъячеек, с которыми мобильная станция в настоящее время осуществляет связь.
- 14Способ определения времени выполнения жесткого переключения канала связи с частоты на частоту внутри ячейки для системы мобильной связи, которая включает в себя мобильную станцию, передающую сигналы пользователей к множеству базовых станций и различающую каждую базовую станцию по пилот-сигналу, множество базовых приемопередающих станций, состоящих по меньшей мере из одного сектора, каждый из которых имеет собственный пилот-сигнал на соответствующей частоте, а также контроллер базовых станций, связывающий упомянутое множество базовых станций с центром коммутации мобильных станций и управляющий переключением канала связи мобильной станции, включающий установление по меньшей мере одной частоты, допускающей переключение, на общую частоту, причем частота, допускающая переключение, является частотой назначения жесткого переключения канала связи с частоты на частоту внутри ячейки среди всех частот, которые могут быть обслужены в настоящее время.
Independent claims14
42 paragraphs, as filed
The invention relates to wireless communications, and more particularly to a method for determining the execution time and the switching direction of the hard handoff base station controller (BSC) of the mobile communications system of multiple access, code-division multiplexing (CDMA).
The cellular mobile communication divides an entire service area into a plurality of cells, where each cell is served by a base transceiver station (BTS). By centralizing the base transceiver stations in each cell of the subscribers can communicate with each other while moving between cells. That is, the configuration of the cellular communication system allows the mobile station to continue a call when the mobile station moves from a cell served by one BTS to another cell serviced by another BTS.
FIG. 1 shows the structure of a cellular communication system using a conventional CDMA technology. As shown in FIG. 1, a cellular communication system includes a mobile station (MS) 40, use the services of mobile communication base transceiver stations (BTS) 30, 31, providing MS 40 mobile services, base station controller (BSC) 20 controlling the BPS 30, 31 and a mobile switching center (MSC) 10 connects BSC 20 to the public switched telephone network (PSTN) 11. The MSC provides services by receiving data from the MS 40 home location register (HLR) 12 and register the location of "visitors" ( VLR) 13.
The cellular communication system of FIG. 1, communication channel from BTS 30 to MS 31, commonly called the forward link, a link from the MS 40 to the BTS 30, 31 - the reverse link in a reverse direction. All direct link associated with a particular BTS share the same shift sequence pseudorandom noise (PN). PN offset is transmitted over a pilot channel in one of the downlink channels, and is defined as a pilot signal. The pilot signal is a signal identification that distinguishes one from another BTS.
A cellular communication system may use a variety of ways to provide services to additional users. One of these methods is the separation of the cells. When cell division of cells is divided into three sectors by the use of three (3) 120-degree antennas with an interval of 120o, so for each of the three sectors allocated antenna. The mobile station identifies each sector antenna as a separate BTS. Cellular communication systems, as well as personal communication systems (SPS), using CDMA technology to provide various types of switching the communication channel to ensure the continuity of the call. Handoff allows to continue making a call by establishing in a short time after the loss of the new channel currently assigned channel time because of movement of the mobile station from one service area to another. The length of time the loss of one channel and the other channel setting is so small that the user will be difficult to determine that handoff has occurred.
If the capacity of the cellular communication system should be increased to provide services to additional users, cellular system allocates additional frequencies BPS (t. E. Channels). The frequency distribution of the RF abbreviated. This situation often occurs in an urban environment, where, in the center of the distribution of the plurality of frequencies is required due to the high population. On the contrary, in the suburban areas can use a smaller number of frequency allocation.
In a conventional cellular communication system by moving the mobile stations communicating on a particular frequency channel (ie. E. RF) to an adjacent service area that is served by another BTS, not serving this particular frequency channel or not having an unoccupied communication channel, the mobile station detects that moves into an area that is served by a neighbor BTS by obtaining pilot signal continuously transmitted pilot channel neighboring BTS. In the case of "hard" handoff involving a mobile station in conventional systems at the mobile station to be installed separate transmitter pilot signal for identifying pilot signals from neighboring BTSs to support "hard" handoff.
A method of "hard" switching of the communication channel, using the pilot signals, is disclosed in U.S. Patent 5594718 entitled "Method and apparatus to provide a" hard "handoff involving a mobile device with a CDMA communication system to alternate access communication system."
In the case of "hard" handoff involving a mobile station, the mobile station via a specially installed therein a transmitter / receiver pilot determines whether the pilot strength neighboring BTS satisfactory. If the mobile station determines that the pilot signal strength is satisfactory, it then calculates the select switching of the communication channel, such as the execution of the switching of the communication channel to request handoff to the BSC. That is, the traditional system is characterized by switching a communication channel with the assistance of the mobile station, whereby the mobile station requests the handoff BSC at runtime, when the level of the pilot is a neighbor BTS predetermined power level, T_ ADD.
If the transmission frequency of a neighboring BTS, the detected mobile station is maintained at an equivalent pilot signal with the sole purpose of "hard" handoff, the BSC decides that despite the requirement of the mobile station to switch a communication channel in the neighboring BTSs have respective available communication resources. BSC instead terminates a "hard" handoff from frequency to frequency by switching to the common frequency, which is generally used as the current serving BTS and the adjacent BTS (m. E. Frequency downshift). BSC then performs "soft" handoff between cells on the neighbor BTSs.
The present invention relates to a method for determining the execution time and the shifting direction in case of "hard" handoff from frequency to frequency when the mobile station moves between two base transceiver stations, which have different frequency allocations (m. E. High RF).
The method according to the present invention comprises the following steps: a base station controller (BSC) receives pilot strength measurement report signal (PSMM) to the mobile station. PSMM comprises a plurality of pilot signals each having a pilot signal level; after BSC PSMM received, it is determined whether all the subcell with which the mobile station is currently connected, subcell border frequency; if it is determined that at least one subcell is not a subcell border frequency, then the handoff general; Otherwise, if it is determined that all the subcell are subcell border frequency BSC PSMM periodically polls all sub-units, to which the mobile station is currently in communication; analyzes the PSMM transmitted from the mobile station in response to the inquiry about the PSMM initiated by the BSC to determine if it is below the level of the pilot signals received from all the sub-units than the predetermined power level T_ DOWN, and activates a timer set to a predetermined time T_ TDOWN capacity, if the level is above the pilot signals received from all the sub-units lower than a predetermined power level; if the timer reaches zero without interruption during the time interval T_ TDOWN, the mobile station is given the command to perform a "hard" handoff from frequency to frequency within a cell on a common frequency, which is served by all base transceiver stations.
The present invention is described in the context of a mobile communication system having a sector-cell structure, however, it is more broadly applicable to systems with a configuration not using such a structure.
An advantage of the present invention is that it is performed only by the software and requires no additional hardware.
Preferred embodiments of the present invention discloses a method for allowing the base station controller (BSC) determining execution time of "hard" handoff from frequency to frequency in a mobile communication system. "Hard handoff from frequency to frequency within a cell can be determined as a handoff in which the mobile station releases the frequency channel and switches to another frequency. To determine the execution time of" hard "handoff from one frequency to the data must be stored in the database Data base transceiver stations (BTS) which is controlled by the BSC. These include the allocation of frequencies (RF) for each sector within each BTS. The present invention determines the sector as a subcell. For example, suppose that the service area of the BTS is divided (divided into sectors) into three sectors, each sector is assigned two frequencies RCH1, RCH2. service area thus consists of six sub-units (m. e. (3 sectors) • (2 RF-sector)). subcell further defined as either subcell common frequency or as subcell border frequency of service based on the status of the common frequencies. That is subcell subcell is defined as the total frequency whenever all common frequencies used by the neighboring sub-units. Subcell is defined as the subcell border frequency whenever not use all common frequencies of neighboring sub-units.
Also stored data described above for each subcell in the database will store additional data field to represent the status of the service frequency which are common to adjacent sub-units. Additional field will indicate which of the designated service area for a particular frequency being serviced or not serviced in the next subcell.
FIG. 2 is an illustration of a service area divided into three cells, "A", "B" and "C". Service area served by the BTS. As shown, the cell "A" is further divided into two sub-units subcell without partitioning into quadrants. In the present example, the cell "A" was assigned (m. E., It controls them) two frequency distribution RCH1 associated with subcell (1) and RCH2 associated with subcell (2). The frequency distribution / interconnection sub-units can be presented as abbreviated RCH1 (1) and RCH2 (2). Namely, the frequency distribution 1 (t. E. RCH1) appointed subcell (1), and the allocation of frequencies is assigned subcell 2 (2).
Referring to FIG. Box 2 "B" is adjacent to the cell "A" and cell "B" in this case assigned to the same two frequency distribution as the cell "A", namely RCH1 and RCH2. Allocation of frequencies assigned RCH2 cells (3) and (6). The cell "B", however, is different from the cell "A" in that subcell cell "B", 3-7, were divided into three sectors (alpha, beta, gamma). Sector alpha and gamma are contiguous to the cell "A", and the gamma sector is adjacent to the cell "C". Cell "B" controls the frequency and RCH1 RCH2. Box "C" contains one subcell (8) which is not divided into sectors. The cell "C" in this case controls the distribution of frequencies RCH1.
Below is an explanation describes each of the above sub-units or as common frequency subcell or as subcell border frequency. Since the neighboring cell "A" subcell (t. E. Subcell 3 and 4 of the cell "B") cater for all frequency controlled cell "A" (t. E. RCH1, RCH2) subcell 1 and 2 of the cell "A" identified as the subcell common frequency. Accordingly, with regard to the cell "B" sous byacheyki 3, 4 and 5 sector alpha and beta are subcell common frequency, because the cell "A" serves all frequency (ie. E. RCH1 and RCH2) controlled sector alpha and beta, which are adjacent to the cell "A".
This subcell (6) to the gamma sector of the cell "B" which is adjacent to the cell "C" subcell (6) is defined as the total frequency subcell, because adjacent cell "C" serves RCH1. Conversely, subcell (7) of the cell "B" is defined as the subcell border frequency, because adjacent cell "C" does not serve RCH2, frequency distribution subcell (7).
Accordingly, with regard to the cell "C" as an adjacent cell "B" serving frequency assigned to the cell "C", namely RCH1, subcell (8) of the cell "C" is defined as the total frequency subcell.
It is not guaranteed that the subcell border frequency can continuously receive communication services at the corresponding frequency in the neighboring BTS, in accordance with the direction of movement of the mobile station. Therefore, a mobile station in real time caters subcell border frequency, first attempts to perform a "hard" handoff from frequency to frequency within a cell to subcell common frequency, and in case of failure, further attempts to perform a "soft" handoff to a cell defined as the destination for the handoff.
To perform "flexible" channel switching connection destination cell, the BTS should establish beforehand at least one frequency among a plurality of frequencies to be used as a frequency downshift. The frequency can be switched, you want to install, should be a common frequency that can generally serve all BPS. Isolation of this frequency makes it possible to perform "flexible" switching of the communication channel for any BTS whenever a mobile station initiates a call.
If subcell data in accordance with the status of service BTS retained and the appointment frequency shift is completed, the BSC requests a measurement report the pilot strength (PSMM) by periodically transmit commands to the mobile station a request for pilot measurements (KZIPS). BSC monitors the radio environment of the mobile station using the PSMM. BSC sets KZIPS period and stores it in a database BPS.
If you are a "hard" handoff from frequency to frequency within the cell, there are additional requirements. BSC shall set a standard parameter T_ DOWN, which is a predetermined threshold value, the corresponding value of the level of the received pilot signal. If the level of the pilot signal received by the mobile station below T_ DOWN for the predetermined time, it will do a "hard" handoff from frequency to frequency. T_ DOWN value is set at a higher level than the conventional threshold, T_ DROP, which is typically used in connection with "hard" handoff.
In accordance with the method according to the present invention, if the BTS instructs the mobile station to perform a "hard" handoff from frequency to frequency within a cell, it must be satisfied the following three conditions: condition 1: all the subcell in which the mobile station sets the channel consist Only sub-units of the border frequency.
Condition 2: the level of pilot sub-units in which the mobile station sets the channel is less than T_ DOWN.
Condition 3: the level of the pilot signals in condition 2 smaller than the threshold T_ DOWN for an extended time equivalent to or greater than a predetermined period of time T_ TDOWN.
Therefore, the BSC can determine the execution time of "hard" handoff from frequency to frequency within a cell, suggesting satisfied if the above three conditions by analyzing the PSMM messages received from the mobile station.
FIG. 3 is a block diagram illustrating a method according to the present invention for determining execution time of "hard" handoff from frequency to frequency within a cell. First, in step 110, the BSC receives from the mobile station measurement report the pilot strength (PSMM). In step 120 of the received message, the BSC can determine whether the subcell with which the mobile station is currently in communication (ie. E., The channel), subcell border frequency. In step 130, if any of the sub-units with which the mobile station currently communicates are not subcell border frequency BSC performs handoff general (r. F. "Flexible"). In particular, the BSC performs a "soft" handoff to the BTS destination subcell common frequency, if any.
In a situation where it is determined that all the subcell with which the mobile station currently communicates are subcell only border frequency BSC determines that a neighboring BTS can not service frequency, which is currently used by the mobile station, a "soft" handoff Communication can not be performed. In this case, the mobile station may still be able to perform a "hard" handoff from frequency to frequency within a cell. To come to this definition, the BSC requests the mobile station by sending a PSMM KZIPS at step 140 to determine whether not a mobile station moves continuously in the direction of BTS, which can not provide service. The mobile station receives and sends KZIPS PSMM to the BSC, by measuring the level of all pilot signals that can be detected currently, then in step 150, the BTS receives in return the requested PSMM.
In step 160, the BTS determines there is not a need for a handoff by analyzing messages PSMM periodically obtained on request KZIPS. In step 180, a determination is that the need for a handoff has not occurred, the BSC compares the strength of pilot signals of all the sub-units with which the mobile station is communicating at present time, with a predetermined threshold T_ DOWN, for determining the state of movement mobile station. If the pilot signals of all the sub-units is less than T_ DOWN, the BSC activates the timer set to T_ TDOWN.
The analysis of the PSMM, that if the level of the signals from all sub-units such that at least one of these values is not less than the threshold T_ DOWN, or in case a further channel subcell common frequency, the timer is disabled. If at step 190 the timer reaches zero without being disconnected during a time interval T_ TDOWN, then at step 170 the BSC instructs the mobile station to perform a "hard" handoff from frequency to frequency within a cell. This is due to the continuous support level of the pilot signal at a level lower or equal T_ DOWN during time interval T_ TDOWN.
In step 160, if the level of the pilot signal BPS is not included in the PSMM message, which is periodically supplied, in step 170 the BSC determines that a shift has been reset link and performs a "hard" handoff from frequency to frequency. That is, the mobile station issues a command to reset the channels that are currently associated with all subcell. In this situation, the channel quality deteriorates so serious that it is necessary to take immediate action.
In step 160, if the new pilot signal was added to the resulting PSMM, then at step 130 the BSC determines that a handoff has occurred, and performs a handoff of a general nature. That is, the mobile station issues a command to add a channel corresponding to the newly detected subcell.
At step 170 the BSC instructs the mobile station to perform a "hard" handoff from frequency to frequency within the cell to the frequency downshift. After performing "hard" handoff from frequency to frequency within a cell BSC completes handoff destination BTS by determining and performing the steps associated with conventional "soft" handoff.
FIG. 4 is a message flow diagram illustrating a method of determining execution time of "hard" handoff from frequency to frequency within the cell according to the present invention. The mobile station 40 transmits the PSMM to the BSC periodically or every time it detects a new pilot signal, and the BSC 20 receives a PSMM from the mobile station 40. Further, the BSC has confirmed that all of the pilot signals reported from the mobile station via PSMM They are boundary frequencies, and in step 210, the current begins to exercise control over "hard" handoff from frequency to frequency within the cell.
For "hard" handoff from frequency to frequency within a cell periodically sends the BSC to the mobile station in accordance with KZIPS period request PSMM. If the mobile station responds to the PSMM, then at step 220, the BSC determines at least whether the level of the pilot signals received via the PSMM than T_ DOWN value. If the level of the received pilot signal is not smaller than T_ DOWN, the BSC sends KZIPS again after a period of the request, at step 230, and again repeats the comparison with the value obtained PSMM T_ DOWN.
If the level of the pilot signals received via the PSMM is less than the value of T_ DOWN, then in step 240 the BSC activates the timer T_ TDOWN. Then the BSC continuously sends and receives KZIPS PSMM.
Continuously analyzing the level of the pilot signals received via the PSMM, BSC in step 250 determines whether the least strength of all pilots than T_ DOWN value for an extended period determined by the value T_ TDOWN. If it is so (t. E. Less), then at step 260 the BSC performs a "hard" handoff from frequency to frequency within a cell.
A mobile station which performs a "hard" handoff from frequency to frequency within the cell to the BSC team can easily perform a "soft" handoff to the BTS is the destination.
The invention is susceptible to various modifications and alternative forms of implementation, while the description includes specific embodiments illustrated in the drawings. However, it should be understood that it is not provided to limit the invention to the particular embodiments modifications, equivalents, and alternatives falling within the scope of the invention as defined in the claims.
Every citation, both ways
| Document | Relation | Office | Cited during |
|---|---|---|---|
| US8358629B2 | Cited by | United States of America | Applicant |
| US8068530B2 | Cited by | United States of America | Applicant |
| US8929353B2 | Cited by | United States of America | Applicant |
| US8676209B2 | Cited by | United States of America | Applicant |
| US8738056B2 | Cited by | United States of America | Applicant |
| US9204379B2 | Cited by | United States of America | Applicant |
| US8027372B2 | Cited by | United States of America | Applicant |
6 members in 4 offices
Priority claims4
| Document | Office | Kind | Date |
|---|---|---|---|
| 19980022290 | Republic of Korea | A | |
| 19980022290 | Republic of Korea | A | |
| 199822290 | – | – | – |
| KR19980022290 | – | – | – |
Members6
| Document | Office | Kind | |
|---|---|---|---|
| CN1239391A | China | A | |
| KR20000001838A | Republic of Korea | A | |
| KR100277058B1 | Republic of Korea | B1 | |
| RU2178239C2This record | Russian Federation | C2 | |
| US6449481B1 | United States of America | B1 | |
| CN1117504C | China | C |
1 legal event, as the office reported them to INPADOC
Events
| Event | Code | |
|---|---|---|
| The patent is invalid due to non-payment of feesMM4A | MM4A |
Numbers
- Publication, DOCDB
- 2178239
- Publication, EPODOC
- RU2178239
- Application
- 9911256209
- Application, DOCDB
- 99112562
- Application, EPODOC
- RU19990112562
Titles
- English
- METHOD FOR DETERMINING EXECUTION TIME OF TIGHT FREQUENCY-TO-FREQUENCY SWITCHING OF COMMUNICATION CHANNEL AND FOR SETTING TIGHT CHANNEL SWITCHING MEDIUM
Classification
- CPC, 6
- H04W36/06
- H04W36/00837
- H04W36/26
- H04W36/38
- H04W36/302
- H04W36/0088
- IPC, 5
- H04B7 26
- H04W36 06
- H04W36 26
- H04W36 30
- H04W36 38