JP2005102319A - Mobile communication system, base station, method for packet transmission timing control, and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication system which is capable of high speed transmission to mobile stations, without causing degradation in the circuit quality of the mobile stations near a cell boundary. <P>SOLUTION: A HS-PDSCH data transmission timing detector 15 executes a program stored in a recording medium 21 for monitoring a transmission timing notice of the HS-PDSCH data from mobile stations and sends the transmission timing notice to a controller 16 when the transmission timing notice is received. The controller 16 controls a transmission power of the HS-PDSCH data from a modulation/encoding part 17 in response to the transmission timing notice from the HS-PDSCH data transmission timing detector 15 and also the controller 16 controls an HS-PDSCH data transmission timing notice part 18 to send a transmission timing information of the HS-PDSCH data to the mobile stations when the HS-PDSCH data is transmitted from an own station to the mobile stations. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mobile communication system, a base station, a packet transmission timing control method used therefor, and a program therefor, and more particularly to a method for controlling transmission timing of data transmitted by the HSDPA (High Speed Downlink Packet Access) method.

  In recent years, mobile terminals such as mobile phones (mobile stations) have been supporting multimedia to handle still images with a large amount of data and short-time moving images, and accordingly, large-capacity and high-speed data transmission. A method is needed. As this large-capacity and high-speed data transmission method, PDSCH (Physical Downlink Shared Channel) or HS-PDSCH (High Speed-Physical Downlink Shared Link), which has only increased the transmission rate in the downlink direction (from the base station to the mobile station). The HSDPA method using the above has been proposed.

  In a mobile communication system that performs data transmission from a base station to a mobile station using the above-described HS-PDSCH, the reception quality of a common pilot signal (CPICH: Common Pilot Channel) transmitted from the base station in soft handover [Ec / Io (energy per chip / interference wave power per unit frequency)] is measured by the mobile station, and the measurement result is notified from the mobile station to the base station controller via the base station.

  In the base station controller, data transmitted by the HSDPA method is transferred to the base station having the highest reception quality of the common pilot signal based on the measurement result at the mobile station. The base station divides the data sent from the base station controller into blocks, and sequentially transmits the data divided into blocks at an optimal data transmission rate according to the downlink channel quality. Here, the optimum data transmission rate is the maximum transmission rate that can be transmitted while satisfying the target error rate. The better the channel quality, that is, the reception SIR [Signal InterferenceRatio: desired in the mobile station] Higher power / (interference power + noise)] enables higher speed transmission. In the HSDPA scheme, since the transmission power in the base station is usually constant, if the noise is constant, the transmission rate according to the HSDPA scheme is inversely proportional to the interference power.

  In the above-described mobile communication system, the transmission timing when transmitting data by the HSDPA method is independently performed at each base station, and data is transmitted from only one base station even at a mobile station near the cell boundary. When data is transmitted to the above mobile station by the HSDPA method, the mobile station transmits data to another mobile station from another base station existing near the boundary of the own cell by the HSDPA method. Then, interference increases in the mobile station near the cell boundary and the reception quality deteriorates. Therefore, there is a problem that the channel quality of the mobile station near the cell boundary is deteriorated and high-speed transmission to the mobile station becomes difficult.

  Also, the mobile station notifies the measurement result of the reception quality of the common pilot signal to the base station control apparatus via the base station, and transmits to the base station with the highest reception quality of the common pilot signal from the base station control apparatus by the HSDPA method. Since the data to be transferred is transferred, a control delay occurs until data transmission by the HSDPA method is started. Since the state of the propagation path also changes during this control delay, the base station selected by the base station controller does not always have the highest channel quality when transmitting data in the HSDPA scheme.

  Accordingly, an object of the present invention is to solve the above-described problems, and a mobile communication system and a base station that can perform high-speed transmission to the mobile station without degrading the channel quality of the mobile station near the cell boundary And a packet transmission timing control method used therefor, and a program therefor.

  The mobile communication system according to the present invention transmits and receives individual signals between a mobile station located at least near the cell boundary of each of the first and second base stations and each of the first and second base stations. A mobile communication system that realizes soft handover and performs data transmission from each of the first and second base stations to the mobile station using an HSDPA (High Speed Downlink Packet Access) method. Control means for controlling data transmission in the HSDPA scheme in the other of the first and second base stations when data transmission in the HSDPA scheme is performed in one of the two base stations. Yes.

  The base station according to the present invention implements soft handover by transmitting and receiving individual signals to and from a mobile station located near a cell boundary, and performs data transfer to the mobile station using an HSDPA (High Speed Downlink Access Access) method. A base station that performs transmission, and includes a control unit that controls data transmission in the HSDPA scheme in the local station when data transmission in the HSDPA scheme is performed in another station.

  The packet transmission timing control method according to the present invention transmits and receives individual signals between a mobile station located at least near the cell boundary of each of the first and second base stations and each of the first and second base stations. This is a packet transmission timing control method for a mobile communication system in which soft handover is realized, and data transmission is performed from each of the first and second base stations to the mobile station using the HSDPA (High Speed Downlink Packet Access) method. When one of the first and second base stations performs data transmission in the HSDPA scheme, the other of the first and second base stations performs data transmission in the HSDPA scheme. A step of controlling.

  A packet transmission timing control method program according to the present invention is a program for transmitting and receiving individual signals between a mobile station located at least near the cell boundary of each of the first and second base stations and each of the first and second base stations. Packet transmission timing control method in a mobile communication system in which soft handover is realized by performing data transmission from each of the first and second base stations to the mobile station using an HSDPA (High Speed Downlink Packet Access) method When the data transmission in the HSDPA scheme is performed in one of the first and second base stations, the program in the other of the first and second base stations. Processing for controlling data transmission in the HSDPA system is executed.

  That is, in the mobile communication system of the present invention, when a mobile station exists at the cell boundary of an adjacent base station and data transmission is performed from the base station to the mobile station using the HSDPA method, the mobile station By controlling the data transmission timing in the HSDPA scheme from the own station to other mobile stations so as not to decrease the packet transmission rate of the mobile station, the transmission rate of the mobile station at the cell boundary of the adjacent base station is improved, It becomes possible to improve the throughput of the entire system.

  More specifically, in the mobile communication system of the present invention, a dedicated signal (DPCH: Dedicated Physical) is located near the cell boundary of the first and second base stations, and between the first and second base stations. When data transmission by the HSDPA method is performed from the first base station to the mobile station performing transmission and reception of (Channel), the data transmission timing by the HSDPA method is notified from the first base station to the mobile station. Then, the transmission timing is notified from the mobile station to the second base station using an uplink individual signal, and the second base station is based on the transmission timing notified from the mobile station according to the HSDPA scheme in its own station. The transmission timing of data is controlled.

  In the control of the data transmission timing in the HSDPA system in the local station, the second base station transmits from the first base station in which the mobile station is notified of the data transmission timing in the HSDPA system to other mobile stations. Make sure that the timing is not the same as the timing.

  Further, in the control of the data transmission timing in the HSDPA system in the own station, when the second base station receives the individual signal on the uplink of the mobile station, the packet reception confirmation signal is included in the individual signal. Then, the transmission power in the data transmission in the HSDPA scheme to other mobile stations is controlled and stopped (this transmission power control includes not only the stop but also a decrease in the transmission power).

  Further, in the control of the data transmission timing in the HSDPA system in the own station, when the second base station receives the individual signal on the uplink of the mobile station, the reception quality of the common pilot signal included in the individual signal The transmission timing of data in the HSDPA scheme to other mobile stations is controlled based on the information regarding the above.

  In this case, the information regarding the reception quality of the common pilot signal added by the mobile station to the uplink dedicated signal includes the measurement result of the reception quality of the common pilot signal from the first and second base stations and the first and second There is information (for example, a preset base station identification code) indicating a base station having a large interference determined from the reception quality of the common pilot signal from the base station.

  Further, when the second base station determines that the interference from the mobile station to the mobile station is large based on the information related to the reception quality of the common pilot signal included in the uplink individual signal of the mobile station, The transmission power in the data transmission in the HSDPA scheme is controlled and stopped.

  As described above, by controlling the transmission timing of data in the HSDPA method from the second base station to another mobile station, the mobile station does not deteriorate the channel quality of the mobile station near the cell boundary. Can be transmitted at high speed.

  That is, when the mobile station is located at the cell boundary, the propagation loss from the communicating base station is large, and the difference in propagation loss from the adjacent base station is small, so that the mobile station receives a large interference. . Thus, for example, when the first mobile station is located near the cell boundary between the first and second base stations, the first base station transmits a packet to the first mobile station, and the second base station Transmits a packet to the second mobile station, the transmission signal of the second base station gives strong interference to the first mobile station, and the packet from the first base station to the first mobile station Transmission rate drops to half or less.

  Therefore, in the present invention, when the first mobile station is located near the cell boundary of the first and second base stations, the adjacent second base station is connected from the first base station to the first mobile station. By controlling the packet transmission timing to the second mobile station so as not to greatly reduce the packet transmission rate, the packet transmission rate to the first mobile station is improved and the throughput of the entire system is increased. ing.

  As described above, according to the present invention, individual signals are transmitted and received between the mobile station located near the cell boundary of each of the first and second base stations and each of the first and second base stations. In a mobile communication system in which soft handover is implemented and data is transmitted from each of the first and second base stations to the mobile station, data transmission is performed in one of the first and second base stations. In some cases, the data transmission in the other of the first and second base stations is performed via the mobile station, so that the mobile station in the vicinity of the cell boundary does not degrade the channel quality, and the mobile station There is an effect that high-speed transmission can be performed to the station.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a mobile communication system according to an embodiment of the present invention. Referring to FIG. 1, a mobile communication system according to an embodiment of the present invention includes base stations 1-1 and 1-2, a base station controller [for example, RNC (Radio Network Controller)] 2, and mobile stations 3-1 to 3-1. -4, and data transmission is performed from the base stations 1-1 and 1-2 to the mobile stations 3-1 to 3-4 by the HSDPA (High Speed Downlink Packet Access) method.

  In the mobile communication system according to the embodiment of the present invention, a plurality of base stations 1-1 and 1-2 are arranged in a service area, and a plurality of base stations 1-1 and 1-2 have a plurality of base stations 1-1 and 1-2. Mobile stations 3-1 to 3-4 exist. The base stations 1-1 and 1-2 are connected to a common base station controller 2, and the base station controller 2 is connected to a communication network (not shown).

  Each of the base stations 1-1 and 1-2 transmits a common pilot signal (CPICH: Common Pilot Channel) to the mobile stations 3-1 to 3-4. The common pilot signal is spread by a different scramble code for each of the cells 101 and 102, and the mobile stations 3-1 to 3-4 have the cells 101 and 102 (that is, the base stations 1-1 and 1-2 depending on the scramble code). ).

  When the mobile station 3-1 receives the downlink data, the mobile station 3-1 sets one or a plurality of base stations 1-1 and 1-2 and individual signals (DPCH: Dedicated Physical Channel) (uplink and downlink) to receive the data. It will be in a waiting state. In this case, the mobile station 3-1 measures the reception quality [Ec / Io (energy per chip / interference wave power per unit frequency)] of the common pilot signal from the base stations 1-1 and 1-2. An individual signal is set between the base station 1-1 having the highest pilot signal reception quality.

  When the difference in reception quality of the common pilot signal between the mobile station 3-1 and the base stations 1-1 and 1-2 is equal to or less than a predetermined value set in advance, the mobile station 3-1 is also individually connected to the base station 1-2. This is a so-called soft handover, in which a signal is set and individual signals are set with a plurality of base stations 1-1 and 1-2.

  Each base station 1-1, 1-2 transmits data of HS-PDSCH (High Speed-Physical Downlink Shared Channel) to the mobile stations 3-1 to 3-4 in blocks. HS-PDSCH is a channel faster than an individual signal, and is transmitted with larger transmission power than a downlink individual signal.

  Each base station 1-1 and 1-2 uses one HS-PDSCH for data transmission to a plurality of mobile stations 3-1 to 3-4. In this case, when the base stations 1-1 and 1-2 perform data transmission to each of the plurality of mobile stations 3-1 to 3-4, the timing of the data transmission is determined, and each mobile station 3-1 Data transmission is performed at different timings for every 3-4.

  At that time, the base station 1-1 divides HS-PDSCH data into blocks and transmits the data to the mobile station 3-1. A CRC (Cyclic Redundancy Check) code (error detection code) is added to this block. When the mobile station 3-1 receives the HS-PDSCH data block, the mobile station 3-1 determines whether there is a reception error in each data block using a CRC code, and notifies the base station 1-1 of the determination result.

  When data to be transmitted from the communication network to the mobile station 3-1 arrives, the base station controller 2 receives the data from the base stations 1-1 and 1-2 for which the mobile station 3-1 has set an individual signal. The data is sent to the base station 1-1 with high reception quality. When the data to be transmitted from the base station controller 2 to the mobile station 3-1 arrives, the base station 1-1 notifies the mobile station 3-1 of data transmission (notification of transmission timing) using an individual signal.

  When the mobile station 3-1 is notified of the advance notice of data transmission from the base station 1-1, the data transmission timing from the base station 1-1 is transmitted to the base station 1-2 during the soft handover in the uplink individual signal. To be notified. The base station 1-2 does not transmit the HS-PDSCH data block to other mobile stations (for example, the mobile station 3-2 or the mobile station 3-4) at the notified transmission timing.

  Here, the transmission power of data transmitted on the HS-PDSCH is constant, and the transmission rate of this data is adaptively controlled by the propagation loss and interference power of the downlink. In this case, if the transmission power and the propagation loss are constant, the transmission rate is inversely proportional to the interference power. Even when the mobile station 3-1 is located at the cell boundary and the difference in propagation loss between adjacent cells is small, data transmission by HS-PDSCH is performed only from the base station 1-1.

  In the above example, the advance notice of data transmission is performed from the base station 1-1. However, when a packet is sent, the mobile station 3-1 is a predetermined time T before the timing at which the packet is sent. The mobile station transmits a signal indicating that a packet is transmitted to the base stations 1-1 and 1-2, and the mobile station 1-1 and 1-2 transmits the signal after a predetermined time T from the mobile station. There is also a configuration in which it can be determined that there is packet transmission in 3-1. In the case of this configuration, a signal indicating that a packet is transmitted from the mobile station 3-1, and the base station 1-2 determines the timing of packet transmission from the base station 1-1 to the mobile station 3-1. Since it can be known, the advance notice of data transmission from the mobile station 3-1 to the base station 1-2 is unnecessary. This is the same in the following description.

  In the above example, the HS-PDSCH data block is not transmitted to other mobile stations at the transmission timing notified by the base station 1-2. In this case, the mobile station moves from the base station 1-1. Since it is only necessary to reduce interference with data transmission to the station 3-1, the transmission power of the HS-PDSCH data block from the base station 1-2 to another mobile station may be reduced. Hereinafter, stopping the data transmission and reducing the transmission power are referred to as transmission power control.

  FIG. 2 is a block diagram showing the configuration of the base station according to the first exemplary embodiment of the present invention. In FIG. 2, the base station 1 includes an antenna 11, a duplexer (DUP) 12, a receiving unit 13, a user information / control information separating unit 14, and an HS-PDSCH data transmission timing detecting unit (hereinafter referred to as transmission). A timing detection unit) 15, a control unit 16, a modulation / coding unit 17, an HS-PDSCH data transmission timing notification unit (hereinafter referred to as a transmission timing notification unit) 18, a synthesis unit 19, and a transmission unit 20 and a recording medium 21. In addition, since a well-known technique can be applied to the call control part, the voice input / output part, and the display part of the base station 1, description of their configuration and operation is omitted.

  The receiving unit 13 sends a signal [DPCH (UL) or the like] received via the antenna 11 and the duplexer 12 to the user information / control information separating unit 14. The user information / control information separating unit 14 separates the received signal from the receiving unit 13 into user information (audio signal, image signal, etc.) and control information, and the user information is the above-described call control part of the base station 1, voice output The control information is sent to the transmission timing detection unit 15 and the control unit 16, respectively.

  The transmission timing detection unit 15 executes a program stored in the recording medium 21 to monitor a transmission timing notification of HS-PDSCH data from a mobile station (not shown). When the transmission timing notification is received, the transmission timing is detected. A notification is sent to the control unit 16.

  The control unit 16 executes the program stored in the recording medium 21 to control information from the user information / control information separation unit 14 and input information from the outside (for example, control information from a base station control device (not shown)). Etc.), and various control signals are generated and output to each unit in the base station 1 for control. The recording medium 21 stores a program executed by each unit of the base station 1 including the control unit 16.

  The control unit 16 controls the transmission power of the HS-PDSCH data from the modulation / coding unit 17 in response to the transmission timing notification from the transmission timing detection unit 15. Further, when transmitting HS-PDSCH data from the own station to the mobile station, the control unit 16 controls the transmission timing notifying unit 18 to transmit the transmission timing information of the HS-PDSCH data to the mobile station.

  The modulation / encoding unit 17 modulates / encodes user information under the control of the control unit 16 and sends the user information to the combining unit 19 as HS-PDSCH data. The transmission timing notification unit 18 transmits the transmission timing information to the synthesis unit 19 when the HS-PDSCH data is transmitted from the modulation / coding unit 17 under the control of the control unit 16.

  The combining unit 19 includes control information from the control unit 16, HS-PDSCH data from the modulation / coding unit 17, transmission timing information from the transmission timing notification unit 18, a call control part and a voice input part of the base station 1, etc. Input signals from the outside are combined and transmitted from the antenna 11 via the transmitter 20 and the duplexer 12 as DPCH (DL) and HS-PDSCH.

  Although not shown, the base stations 1-1 and 1-2 shown in FIG. 1 have the same configuration as that of the base station 1 shown in FIG. It is the same.

  FIG. 3 is a block diagram showing the configuration of the mobile station according to the first embodiment of the present invention. In FIG. 3, the mobile station 3 includes an antenna 31, a duplexer (DUP) 32, a receiver 33, a user information / control information separator 34, a controller 35, a demodulator / decoder 36, The HS-PDSCH data transmission timing detection / notification unit (hereinafter referred to as a transmission timing detection / notification unit) 37, a synthesis unit 38, a transmission unit 39, and a recording medium 40 are included. In addition, since a well-known technique can be applied to the call control part, the voice input / output part, and the display part of the mobile station 3, description of their configuration and operation is omitted.

  The receiving unit 33 sends a signal (common pilot signal, individual signal, HS-PDSCH) received via the antenna 31 and the transmission / reception duplexer 32 to the user information / control information separation unit 34. The user information / control information separating unit 34 separates the received signal from the receiving unit 33 into user information (sound signal, image signal, etc.) and control information, and the user information is demodulated / decoded unit 36, the mobile station 3 described above. The control information is sent to the control unit 35 and the transmission timing detection / notification unit 37, respectively.

  The control unit 35 executes a program stored in the recording medium 40 to thereby control information from the user information / control information separation unit 34 and input information from the outside (for example, user information from a numeric keypad or a voice input part). Various control signals are generated based on the signal and output to each unit in the mobile station 3 for control, and control information for the base station 1 is generated and sent to the combining unit 38. The recording medium 40 stores a program executed by each unit of the mobile station 3 including the control unit 35.

  The demodulation / decoding unit 36 demodulates and decodes the user information separated by the user information / control information separation unit 34 and outputs HS-PDSCH data to each unit in the mobile station 3. The transmission timing detection / notification unit 37 monitors whether there is transmission timing information of HS-PDSCH data in the control information separated by the user information / control information separation unit 34, and when detecting the transmission timing information, Information is sent to the control unit 35 and transmission timing information to be sent to adjacent base stations is sent to the combining unit 38.

  The combining unit 38 combines the control information from the control unit 35, the transmission timing information from the transmission timing detection / notification unit 37, the input signals from the outside such as the call control part and the voice input part of the mobile station 3, and the like. The individual signal [DPCH (UL)] is transmitted from the antenna 31 via the transmitter 39 and the duplexer 32.

  Although not shown, the mobile stations 3-1 to 3-4 shown in FIG. 1 have the same configuration as that of the mobile station 3 shown in FIG. It is the same.

  FIG. 4 is a sequence chart showing HS-PDSCH data transmission timing adjustment processing according to the first embodiment of the present invention, and FIGS. 5 and 6 show the base station 1 of FIG. 1 according to the first embodiment of the present invention. -1 and 1-2 are flowcharts showing HS-PDSCH data transmission timing adjustment processing, and FIG. 7 is a flowchart of HS-PDSCH in the mobile station 3-1 of FIG. 1 according to the first embodiment of the present invention. It is a flowchart which shows a data reception process. The HS-PDSCH data transmission / reception according to the first embodiment of the present invention will be described with reference to FIGS. In FIG. 4, the base station controller 2 is an RNC, the base stations 1-1 and 1-2 are BS # 1 and BS # 2, the mobile station 3-1 is MS # 1, and the mobile station 3- 1 is in soft handover with the base stations 1-1 and 1-2.

  When the base station 1-1 receives data to be transmitted from the base station controller 2 to the mobile station 3-1 (step S1 in FIG. 5), the base station 1-1 uses the downlink individual signal to send the HS- A transmission notice of the PDSCH data block is transmitted (step S2 in FIG. 5). Thereafter, the base station 1-1 transmits an HS-PDSCH data block to the mobile station 3-1 (step S3 in FIG. 5).

  At this time, when the mobile station 3-1 receives the HS-PDSCH data block transmission notice from the base station 1-1 (step S 11 in FIG. 7), the base station 1-1 uses the data block transmission notice as transmission timing information. 2 (step S12 in FIG. 7).

  When the mobile station 3-1 receives the HS-PDSCH data block (packets # 1, # 2,...) From the base station 1-1 (step S 13 in FIG. 7), the data block is the last data block. Otherwise (step S14 in FIG. 7), a data block reception response (ACK: acknowledgment) is transmitted to the base stations 1-1 and 1-2 in soft handover (step S15 in FIG. 7).

  Each time the base station 1-1 receives a data block reception response from the mobile station 3-1 (step S4 in FIG. 5), the base station 1-1 sequentially transmits the next data block to the mobile station 3-1 (step S5 in FIG. 5). ).

  On the other hand, when the base station 1-2 receives the transmission timing information from the mobile station 3-1 (step S7 in FIG. 6), the base station 1-2 is based on the timing at which the data block is transmitted from the base station 1-1 to the mobile station 3-1. The transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or 3-4 is controlled (step S8 in FIG. 6).

  When the mobile station 3-1 receives the last data block (packet #n) from the base station 1-1 (step S 14 in FIG. 7), the mobile station 3-1 receives the data block from the base stations 1-1 and 1-2 during soft handover. A reception end notification is transmitted (step S16 in FIG. 7).

  When receiving the data block reception end notification from the mobile station 3-1 (step S6 in FIG. 5), the base station 1-1 returns to step S1 and waits for the next data from the base station control device 2. Further, when the base station 1-2 receives the data block reception end notification from the mobile station 3-1 (step S9 in FIG. 6), the base station 1-2 performs HS- from the own station to another mobile station 3-2 or the mobile station 3-4. The control of the transmission power of the PDSCH data block is canceled (step S10 in FIG. 6), and the process returns to step S1 and the next data from the base station controller 2 or from the mobile stations 3-1, 3-2 and 3-4. Wait for transmission timing information.

  Thus, by reducing the large interference due to the HS-PDSCH from the adjacent cell 102 with a small difference in propagation loss, the HS-PDSCH from the base station 1-1 to the mobile station 3-1 near the boundary of the cell 101 is obtained. Transmission speed of transmission can be improved.

  Even when the HS-PDSCH is actually transmitted from the base station 1-1 whose propagation loss is not minimum, the HS transmitted from the base station 1-2 whose propagation loss is minimum to the other mobile stations 3-2 and 3-4. -Large interference due to PDSCH can be reduced. That is, in the mobile station 3-1, interference due to multipath can be canceled, but it is difficult to cancel interference from other base stations 1-2, and the propagation loss is minimum as described above. Since it is possible to reduce the large interference due to the HS-PDSCH transmitted from the base station 1-2 to the other mobile stations 3-2 and 3-4, the HS- from the base station 1-1 to the mobile station 3-1. There are many effects on improving the transmission rate of PDSCH transmission.

  In this case, the throughput of the entire system can be improved by slightly delaying the transmission of the HS-PDSCH in the adjacent cell 102. In addition, by not transmitting at the same time, a strong interference wave is not given to the mobile station 3-1 existing in the vicinity of the cell boundary, so that the transmission rate for the mobile station 3-1 can be increased more than twice. The throughput per hit can be increased.

  In particular, since the signal power is small near the cell boundary, the ratio between the noise power and the interference wave power is large. Therefore, since the SIR (Signal Interference Ratio) is small and the transmission rate is low, it takes a longer time to use the channel to send the same amount of data than the mobile stations 3-2 to 3-4 other than those near the cell boundary. Become. Therefore, increasing the transmission rate for such a mobile station 3-1 has a great effect of increasing the throughput of the entire system.

  On the other hand, if the HS-PDSCH is not transmitted to the mobile station 3-1 near the cell boundary in each cell 101, 102, Since large interference wave power is not given to the mobile stations 3-2 to 3-4, the decrease in the transmission rate is relatively small. Therefore, the throughput of the entire system can be improved by performing packet transmission simultaneously between adjacent cells 101 and 102.

  As described above, depending on the packet transmission status in the adjacent cells 101 and 102, it is determined whether or not to simultaneously transmit to the mobile stations 3-1 to 3-4 of the own cell. Even in situations, the overall system throughput can be maximized.

  In this embodiment, the base stations 1-1 and 1-2 receive the data block reception end notification from the mobile station 3-1, but the data block reception response [ACK] is received from the mobile station 3-1. The end of reception of the data block can also be detected by detecting that there is no data block reception response from the mobile station 3-1 for a predetermined time after receiving (acknowledgement) or NACK (negative acknowledgment). Therefore, the control of the transmission power of the HS-PDSCH data block may be canceled in response to this detection. This is the same in the following description.

  FIG. 8 is a block diagram showing a configuration of a base station according to the second exemplary embodiment of the present invention. In FIG. 8, the base station 4 according to the second embodiment of the present invention performs control according to the detection result of the codeword detection unit 41 and the codeword detection unit 41 instead of the transmission timing detection unit 15 and the control unit 16. The configuration is the same as that of the base station 1 according to the first embodiment of the present invention shown in FIG. 2 except that the control unit 42 is provided, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the first embodiment of the present invention.

  When the codeword detection unit 41 detects an identification code of the own station from a base station control device (not shown), the codeword detection unit 41 holds the identification code and receives the codeword received from the mobile station (not shown) in soft handover. If they match, the control unit 42 is notified of this. When notified of the coincidence with the identification code of the local station, the control unit 42 controls the transmission power of the HS-PDSCH data to other mobile stations (not shown).

  FIG. 9 is a block diagram showing a configuration of a mobile station according to the second exemplary embodiment of the present invention. In FIG. 9, the mobile station 5 according to the second embodiment of the present invention is provided with a reception quality measurement unit 51 and a codeword notification unit 52 in place of the transmission timing detection / notification unit 37. The configuration is the same as that of the mobile station 3 according to the first embodiment, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the first embodiment of the present invention.

  The reception quality measurement unit 51 measures the reception quality of the common pilot signal separated by the user information / control information separation unit 34 and notifies the codeword notification unit 52 of the measurement result. If the difference in reception quality of the common pilot signal from the base station (not shown) during soft handover is equal to or greater than a preset threshold value, the codeword notification unit 52 transmits the HS-PDSCH data. A code word indicating the identification code is sent to the synthesizing unit 38 to the base station other than the base station and notified to the base station using an uplink individual signal.

  Although not shown, the second embodiment of the present invention has the same configuration as the mobile communication system shown in FIG. 1, and the base stations 1-1 and 1-2 shown in FIG. The configuration is the same as the configuration of the mobile station 4 shown, and the operation is the same as the operation of the mobile station 4. The mobile stations 3-1 to 3-4 shown in FIG. 1 have the same configuration as that of the mobile station 5 shown in FIG. 9 described above, and the operation is the same as that of the mobile station 5.

  FIG. 10 is a sequence chart showing HS-PDSCH data transmission timing adjustment processing according to the second embodiment of the present invention. FIGS. 11 and 12 show the base station 1 of FIG. 1 according to the second embodiment of the present invention. -1 and 1-2 are flowcharts showing HS-PDSCH data transmission timing adjustment processing, and FIG. 13 is a flowchart of HS-PDSCH in the mobile station 3-1 of FIG. 1 according to the second embodiment of the present invention. It is a flowchart which shows a data reception process. The HS-PDSCH data transmission / reception according to the second embodiment of the present invention will be described with reference to FIG. 1 and FIGS. In FIG. 10, the base station controller 2 is RNC, the base stations 1-1 and 1-2 are BS # 1 and BS # 2, the mobile station 3-1 is MS # 1, and the mobile station 3- 1 is in soft handover with the base stations 1-1 and 1-2.

  The base station controller 2 determines identification codes for the base stations 1-1 and 1-2. In that case, the base station controller 2 selects the identification codes of the base stations 1-1 and 1-2 so as not to overlap each other, for example, from a, b, c,. After that, the base station control device 2 notifies the determined identification codes to the base stations 1-1 and 1-2, and sends the identification codes of both the base stations 1-1 and 1-2 to the mobile station 3-1. Notice.

  When the base station 1-1 receives data to be transmitted from the base station controller 2 to the mobile station 3-1 (step S21 in FIG. 11), the base station 1-1 transmits an HS-PDSCH data block to the mobile station 3-1. FIG. 11 step S22).

  At this time, when the mobile station 3-1 receives the HS-PDSCH data block (packets # 1, # 2,...) From the base station 1-1 (steps S31 and S32 in FIG. 13), the data block is the last. If the received data block is not a data block (step S33 in FIG. 13), the reception quality measurement unit 51 measures the reception quality of the common pilot signal from each of the base stations 1-1 and 1-2 during the soft handover, and the difference between these reception qualities. Is greater than or equal to a preset threshold value (step S34 in FIG. 13). If the difference in reception quality is not greater than or equal to the threshold value, the mobile station 3-1 transmits a data block reception response (ACK) to the base stations 1-1 and 1-2 during soft handover (step S 35 in FIG. 13). ).

  If the difference in reception quality is equal to or greater than the threshold value, the mobile station 3-1 transmits a data block reception response to the base station 1-1 that transmits the HS-PDSCH data block, and the HS-PDSCH A data block reception response to which the codeword notified from the codeword notification unit 52 is added is transmitted to the base station 1-2 that does not transmit the data block (step S36 in FIG. 13).

  Each time the base station 1-1 receives a data block reception response from the mobile station 3-1 (step S23 in FIG. 11), the base station 1-1 sequentially transmits the next data block to the mobile station 3-1 (step S24 in FIG. 11). ).

  On the other hand, in the base station 1-2, a code word is added to the response to the data block reception from the mobile station 3-1, and if the code word matches the identification code of the own station (step S26 in FIG. 12), The transmission power of the data block of HS-PDSCH from the station to another mobile station 3-2 or mobile station 3-4 is controlled (step S27 in FIG. 12). Thereafter, in the base station 1-2, while the code word is added to the data block reception response from the mobile station 3-1, the HS- from the own station to another mobile station 3-2 or the mobile station 3-4. Controls the transmission power of the PDSCH data block.

  When the mobile station 3-1 receives the last data block (packet #n) from the base station 1-1 (step S 33 in FIG. 13), the mobile station 3-1 transmits the data block to the base stations 1-1 and 1-2 during soft handover. A reception end notification is transmitted (step S37 in FIG. 13).

  When receiving the data block reception end notification from the mobile station 3-1 (step S 25 in FIG. 11), the base station 1-1 returns to step S 21 and waits for the next data from the base station controller 2. Further, when the base station 1-2 receives the data block reception end notification from the mobile station 3-1, that is, when the transmission of the code word indicating the identification code of the mobile station 3-1 stops (step S28 in FIG. 12). ) Cancels the control of the transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or 3-4 (step S29 in FIG. 12), and returns to step S21 to return to the base station controller. Wait for the next data from 2 or a codeword from mobile stations 3-1, 3-2 and 3-4.

  Since the base stations 1-1 and 1-2 performing soft handover are determined via the base station control apparatus 2, there is a delay until the base stations 1-1 and 1-2 are updated. Therefore, even in a base station where the difference in propagation loss has already become large, soft handover of individual signals is performed during the update delay.

  Therefore, as in the first embodiment of the present invention, when the base station 1-1 transmits the HS-PDSCH data to the mobile station 3-1, the HS-PDSCH data is always transmitted to the base station 1-2. When the transmission power of the base station 1-2 is controlled, the transmission of the HS-PDSCH data from the base station 1-2 does not cause significant interference to the mobile station 3-1. Will be controlled. Therefore, although the throughput of the mobile station 3-1 is not actually improved, the throughput of the base station 1-2 may be reduced, and the overall system throughput may be reduced.

  On the other hand, in this embodiment, the mobile station 3-1 measures the reception quality of the common pilot signal of the base stations 1-1 and 1-2, and the interference from the base station 1-2 is larger than a certain level. Since the base station 1-2 is directly notified, only when the mobile station 3-1 is actually subjected to large interference, the base station 1-2 is directed to the other mobile stations 3-2 and 3-4. HS-PDSCH data transmission power can be controlled, and the throughput of the entire system can be maximized.

  Even when the mobile station 3-1 and the base stations 1-1 and 1-2 transmit and receive individual signals, the difference in propagation loss between the base station 1-1 and the base station 1-2 is large. Then, transmission of HS-PDSCH data from the base station 1-2 to the other mobile stations 3-2 and 3-4 is performed as usual, and interference from the base station 1-2 to the mobile station 3-1 thereby occurs. Therefore, the throughput of the entire system can be maximized. The other effects of this embodiment are the same as those of the first embodiment of the present invention.

  FIG. 14 is a sequence chart showing HS-PDSCH data transmission timing adjustment processing according to the third embodiment of the present invention. FIGS. 15 and 16 show the base station 1 of FIG. 1 according to the third embodiment of the present invention. FIG. 17 is a flowchart showing HS-PDSCH data transmission timing adjustment processing in −1, 1-2, and FIG. 17 is a flowchart of HS-PDSCH in the mobile station 3-1 in FIG. 1 according to the third embodiment of the present invention. It is a flowchart which shows a data reception process. The HS-PDSCH data transmission / reception according to the third embodiment of the present invention will be described with reference to FIG. 1 and FIGS. In FIG. 14, the base station controller 2 is an RNC, the base stations 1-1 and 1-2 are BS # 1 and BS # 2, the mobile station 3-1 is MS # 1, and the mobile station 3- 1 is in soft handover with the base stations 1-1 and 1-2.

  Although not shown, the third embodiment of the present invention has the same configuration as that of the mobile communication system shown in FIG. 1, and the base stations 1-1 and 1-2 shown in FIG. The configuration is the same as the configuration of the mobile station 4 shown, and the operation is the same as the operation of the mobile station 4. The mobile stations 3-1 to 3-4 shown in FIG. 1 have the same configuration as that of the mobile station 5 shown in FIG. 9 described above, and the operation is the same as that of the mobile station 5.

  The base station controller 2 determines identification codes for the base stations 1-1 and 1-2. In that case, the base station controller 2 selects the identification codes of the base stations 1-1 and 1-2 so as not to overlap each other, for example, from a, b, c,. After that, the base station control device 2 notifies the determined identification codes to the base stations 1-1 and 1-2, and sends the identification codes of both the base stations 1-1 and 1-2 to the mobile station 3-1. Notice.

  When the base station 1-1 receives data to be transmitted from the base station controller 2 to the mobile station 3-1 (step S41 in FIG. 15), the base station 1-1 uses the downlink individual signal to send the HS- A PDSCH data block transmission advance notice is transmitted (step S42 in FIG. 15). Thereafter, the base station 1-1 transmits an HS-PDSCH data block to the mobile station 3-1 (step S43 in FIG. 15).

  At this time, when the mobile station 3-1 receives the HS-PDSCH data block transmission advance notice from the base station 1-1 (step S 51 in FIG. 17), the base station 1-1 uses the data block transmission advance notice as transmission timing information. 2 (step S52 in FIG. 17).

  When the mobile station 3-1 receives the HS-PDSCH data block (packets # 1, # 2,...) From the base station 1-1 (step S 53 in FIG. 17), the data block is the last data block. Otherwise (step S54 in FIG. 17), the reception quality measurement unit 51 measures the reception quality of the common pilot signal from each of the base stations 1-1 and 1-2 during the soft handover, and the difference between these reception qualities is set in advance. It is determined whether or not the threshold value is exceeded (step S55 in FIG. 17). If the difference in reception quality is not greater than or equal to the threshold value, the mobile station 3-1 transmits a data block reception response (ACK) to the base stations 1-1 and 1-2 during soft handover (step S 56 in FIG. 17). ).

  If the difference in reception quality is equal to or greater than the threshold value, the mobile station 3-1 transmits a data block reception response to the base station 1-1 that transmits the HS-PDSCH data block, and the HS-PDSCH A data block reception response to which the code word notified from the code word notification unit 52 is added is transmitted to the base station 1-2 that does not transmit the data block (step S57 in FIG. 17).

  Each time the base station 1-1 receives a data block reception response from the mobile station 3-1 (step S44 in FIG. 15), the base station 1-1 sequentially transmits the next data block to the mobile station 3-1 (step S45 in FIG. 15). ).

  On the other hand, when the base station 1-2 receives the transmission timing information from the mobile station 3-1 (step S47 in FIG. 16), the base station 1-2 is based on the timing at which the data block is transmitted from the base station 1-1 to the mobile station 3-1. The transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or 3-4 is controlled (step S48 in FIG. 16). Thereafter, in the base station 1-2, while the code word is added to the data block reception response from the mobile station 3-1, the HS- from the own station to another mobile station 3-2 or the mobile station 3-4. Controls the transmission power of the PDSCH data block.

  When the mobile station 3-1 receives the last data block (packet #n) from the base station 1-1 (step S 54 in FIG. 17), the mobile station 3-1 receives the data block from the base stations 1-1 and 1-2 during the soft handover. A reception end notification is transmitted (step S58 in FIG. 17).

  When receiving the data block reception end notification from the mobile station 3-1 (step S 46 in FIG. 15), the base station 1-1 returns to step S 41 and waits for the next data from the base station controller 2. In addition, when the base station 1-2 receives the data block reception end notification from the mobile station 3-1, that is, when the transmission of the code word indicating the identification code of the mobile station 3-1 stops (step S49 in FIG. 16). ) Cancels the control of the transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or 3-4 (step S50 in FIG. 16), and returns to step S41 to return to the base station controller. 2 or the transmission timing information from the mobile stations 3-1, 3-2 and 3-4.

  In this embodiment, as in the second embodiment of the present invention described above, the base station 1-2 waits for the arrival of a codeword from the mobile station 3-1, and controls the transmission power of the HS-PDSCH data block. The transmission power of the HS-PDSCH data block is controlled based on the transmission timing information from the mobile station 3-1, so that the throughput is increased from the beginning when the interference of the base station 1-2 is large from the beginning. Can be improved. The other effects of this embodiment are the same as those of the second embodiment of the present invention.

  FIG. 18 is a block diagram showing the configuration of a mobile communication system according to the fourth embodiment of the present invention. 18, the mobile communication system according to the fourth embodiment of the present invention has the same configuration as the mobile communication system according to the embodiment of the present invention shown in FIG. 1, except that base station 1-3 and its cell 103 are added. It has become.

  That is, FIG. 18 shows a configuration in which the mobile station 3-1 transmits and receives individual signals to and from the three base stations 1-1 to 1-3. In this case, the base station control device 2 determines the identification codes of the base stations 1-1 to 1-3, and also determines the identification codes of the combination thereof, and the determined content is determined for each base station 1-1. To 1-3 and also to the mobile station 3-1.

  FIG. 19 is a diagram illustrating an example of an identification code determined by the base station control device 2 of FIG. In FIG. 19, the base station control apparatus 2 uses “010101” as the identification code of the base station 1-1 (BS # 1), “010110” as the identification code of the base station 1-2 (BS # 2), and “010111”. "101101" is the identification code of the base station 1-3 (BS # 3), "101101" is the identification code of the combination of the base station 1-1 and the base station 1-2 (BS # 1 & BS # 2), and "111101" Is the identification code of the combination of base station 1-2 and base station 1-3 (BS # 2 & BS # 3).

  The mobile station 3-1 holds the above identification code, the reception quality measurement unit 51 measures the reception quality of the common pilot signal from each of the base stations 1-1 to 1-3 during the soft handover, and receives them. When the difference in quality is equal to or greater than a preset threshold value, the base stations 1-2 and 1-3 other than the base station 1-1 transmitting the HS-PDSCH data block are transferred to the base stations 1-2 and 1-2. A code word indicating the identification code “111101” indicating the combination of 1-3 is added to the response to the data block reception to the base stations 1-2 and 1-3 and transmitted. If the base station whose reception quality difference is equal to or greater than the threshold is, for example, only the base station 1-3, the mobile station 3-1 shows an identification code “010111” indicating the base station 1-3. The codeword is added to the response to the data block reception to the base station 1-3 and transmitted.

  As a result, the transmission power of the HS-PDSCH data blocks of the base stations 1-2 and 1-3 that interfere with the mobile station 3-1 can be controlled, so that the three base stations 1-1 to 1-1 can be controlled. Even when soft handover is performed at -3, the throughput at the mobile station 3-1 can be improved. In this embodiment, the case where the soft handover is performed by the three base stations 1-1 to 1-3 has been described. However, the present invention can also be applied to the case where the soft handover is performed by four or more base stations.

  FIG. 20 is a block diagram showing a configuration of a base station according to the fifth example of the present invention. In FIG. 20, the base station 6 according to the fifth embodiment of the present invention performs control according to the detection results of the reception quality detection unit 61 and the reception quality detection unit 61 instead of the transmission timing detection unit 15 and the control unit 16. The configuration is the same as that of the base station 1 according to the first embodiment of the present invention of FIG. 2 except that the control unit 62 is provided, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the first embodiment of the present invention.

  The reception quality detection unit 61 notifies the control unit 62 of the reception quality of the common pilot signal received from the mobile station (not shown) in soft handover and the other base station (not shown) in soft handover. . The control unit 62 calculates the difference between the reception quality of the local station and the reception quality of the other base station. If the difference is equal to or greater than a predetermined threshold value set in advance, another mobile station (not shown) ) To control the transmission power of HS-PDSCH data.

  FIG. 21 is a block diagram showing the configuration of a mobile station according to the fifth example of the present invention. In FIG. 21, the mobile station 7 according to the fifth embodiment of the present invention is provided with a reception quality measurement unit 71 and a reception quality notification unit 72 instead of the transmission timing detection / notification unit 37. The configuration is the same as that of the mobile station 3 according to the first embodiment, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the first embodiment of the present invention.

  The reception quality measurement unit 71 measures the reception quality of the common pilot signal separated by the user information / control information separation unit 34 and notifies the reception quality notification unit 72 of the measurement result. The reception quality notifying unit 72 sends the reception quality of the common pilot signal from the base station (not shown) during soft handover to the combining unit 38, and the uplink quality is transmitted to the base station other than the base station that transmits the HS-PDSCH data. Notification using individual signals.

  Although not shown, the fifth embodiment of the present invention has the same configuration as the mobile communication system shown in FIG. 1, and the base stations 1-1 and 1-2 shown in FIG. The configuration is the same as the configuration of the mobile station 6 shown, and the operation is the same as the operation of the mobile station 6. Further, the mobile stations 3-1 to 3-4 shown in FIG. 1 have the same configuration as that of the mobile station 7 shown in FIG. 21 described above, and the operation is the same as the operation of the mobile station 7.

  FIG. 22 is a sequence chart showing HS-PDSCH data transmission timing adjustment processing according to the fifth embodiment of the present invention. FIGS. 23 and 24 show the base station 1 of FIG. 1 according to the fifth embodiment of the present invention. FIG. 25 is a flowchart illustrating HS-PDSCH data transmission timing adjustment processing at −1, 1-2, and FIG. 25 is a flowchart illustrating HS-PDSCH transmission at the mobile station 3-1 in FIG. 1 according to the fifth embodiment of the present invention. It is a flowchart which shows a data reception process. The HS-PDSCH data transmission / reception according to the fifth embodiment of the present invention will be described with reference to FIG. 1 and FIGS. In FIG. 22, base station controller 2 is RNC, base stations 1-1 and 1-2 are BS # 1 and BS # 2, mobile station 3-1 is MS # 1, and mobile station 3- 1 is in soft handover with the base stations 1-1 and 1-2.

  When the base station 1-1 receives data to be transmitted from the base station controller 2 to the mobile station 3-1, (step S61 in FIG. 23), the base station 1-1 transmits an HS-PDSCH data block to the mobile station 3-1. FIG. 23 step S62).

  At this time, when the mobile station 3-1 receives the HS-PDSCH data block (packets # 1, # 2,...) From the base station 1-1 (steps S81 and S82 in FIG. 25), the data block is the last. If it is not a data block (step S83 in FIG. 25), the reception quality measurement unit 71 measures the reception quality of the common pilot signal from each of the base stations 1-1 and 1-2 during soft handover, and the HS-PDSCH data A data block reception response (ACK) is transmitted to the base station 1-1 that transmits the block, and the reception quality notified from the reception quality notification unit 72 to the base station 1-2 that does not transmit the HS-PDSCH data block. A response for receiving the added data block is transmitted (step S84 in FIG. 25).

  Each time the base station 1-1 receives a data block reception response from the mobile station 3-1 (step S63 in FIG. 23), the base station 1-1 sequentially transmits the next data block to the mobile station 3-1 (step S64 in FIG. 23). ).

  On the other hand, if the reception quality is added to the response to the data block reception from the mobile station 3-1 in the base station 1-2 (step S 66 in FIG. 24), the reception of each of the received base stations 1-1 and 1-2. A difference in quality is calculated and compared (step S67 in FIG. 24). If the difference in reception quality between the base stations 1-1 and 1-2 is equal to or greater than a predetermined threshold value set in advance (step S68 in FIG. 24), the base station 1-2 changes from its own station to another mobile station 3 -2 or the transmission power of the HS-PDSCH data block to the mobile station 3-4 is controlled (step S69 in FIG. 24). Thereafter, while the difference in the reception quality of each of the base stations 1-1 and 1-2 from the mobile station 3-1 is greater than or equal to a predetermined threshold, the base station 1-2 changes from its own station to another mobile station 3- 2 or the transmission power of the data block of HS-PDSCH to the mobile station 3-4.

  Further, when the mobile station 3-1 receives the last data block (packet #n) from the base station 1-1 (step S83 in FIG. 25), the mobile station 3-1 sends the data block to the base stations 1-1 and 1-2 in soft handover. A reception end notification is transmitted (step S85 in FIG. 25).

  When receiving the data block reception end notification from the mobile station 3-1 (step S 65 in FIG. 23), the base station 1-1 returns to step S 61 and waits for the next data from the base station controller 2. Also, the base station 1-2 has a difference in reception quality between the base stations 1-1 and 1-2 from the mobile station 3-1 that is equal to or less than a predetermined threshold (step S68 in FIG. 24), and HS-PDSCH. If the transmission power of the data block is being controlled (step S70 in FIG. 24), the control of the transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or mobile station 3-4 is canceled. Then (step S71 in FIG. 24), the process returns to step S61 and waits for the next data from the base station controller 2 or the reception quality from the mobile stations 3-1, 3-2 and 3-4.

  On the other hand, in this embodiment, the mobile station 3-1 measures the reception quality of the common pilot signal of the base stations 1-1 and 1-2, and the interference from the own station in the base station 1-2 is below a certain level. If it is large, the throughput of the entire system can be maximized by directly controlling the transmission power of HS-PDSCH data from the own station to the other mobile stations 3-2 and 3-4. The remaining effects of this embodiment are the same as those of the first and second embodiments of the present invention.

  FIG. 26 is a sequence chart showing HS-PDSCH data transmission timing adjustment processing according to the sixth embodiment of the present invention. FIGS. 27 and 28 show the base station 1 of FIG. 1 according to the sixth embodiment of the present invention. FIG. 29 is a flowchart showing HS-PDSCH data transmission timing adjustment processing in −1, 1-2, and FIG. 29 is a flowchart of HS-PDSCH in the mobile station 3-1 in FIG. 1 according to the sixth embodiment of the present invention. It is a flowchart which shows a data reception process. The HS-PDSCH data transmission / reception according to the sixth embodiment of the present invention will be described with reference to FIG. 1 and FIGS. In FIG. 26, the base station controller 2 is an RNC, the base stations 1-1 and 1-2 are BS # 1 and BS # 2, the mobile station 3-1 is MS # 1, and the mobile station 3- 1 is in soft handover with the base stations 1-1 and 1-2.

  When the base station 1-1 receives data to be transmitted from the base station controller 2 to the mobile station 3-1 (step S91 in FIG. 27), the base station 1-1 uses the downlink individual signal to send the HS- A transmission notice of the PDSCH data block is transmitted (step S92 in FIG. 27). Thereafter, the base station 1-1 transmits an HS-PDSCH data block to the mobile station 3-1 (step S93 in FIG. 27).

  At this time, when the mobile station 3-1 receives the HS-PDSCH data block transmission notice from the base station 1-1 (step S 111 in FIG. 29), the base station 1-1 uses the data block transmission notice as transmission timing information. 2 (step S112 in FIG. 29).

  When the mobile station 3-1 receives the HS-PDSCH data block (packets # 1, # 2,...) From the base station 1-1 (step S 113 in FIG. 29), the data block is the last data block. Otherwise (step S114 in FIG. 29), the reception quality measuring unit 71 measures the reception quality of the common pilot signal from each of the base stations 1-1 and 1-2 during soft handover, and transmits the HS-PDSCH data block. A data block reception response (ACK) is transmitted to the base station 1-1 to be transmitted, and the reception quality notified from the reception quality notification unit 72 is added to the base station 1-2 that does not transmit the HS-PDSCH data block. A block reception response is transmitted (step S115 in FIG. 29).

  Each time the base station 1-1 receives a data block reception response from the mobile station 3-1 (step S94 in FIG. 27), the base station 1-1 sequentially transmits the next data block to the mobile station 3-1 (step S95 in FIG. 27). ).

  On the other hand, when the base station 1-2 receives the transmission timing information from the mobile station 3-1 (step S97 in FIG. 28), it is based on the timing at which the data block is transmitted from the base station 1-1 to the mobile station 3-1. The transmission power of the HS-PDSCH data block from the own station to another mobile station 3-2 or 3-4 is controlled (step S98 in FIG. 28).

  In this case, if the reception quality is added to the response to the data block reception from the mobile station 3-1 (step S 99 in FIG. 28), the base station 1-2 receives each of the received base stations 1-1 and 1-2. A difference in reception quality is calculated and compared (step S100 in FIG. 28). If the difference in reception quality between the base stations 1-1 and 1-2 is greater than or equal to a predetermined threshold value set in advance (step S101 in FIG. 28), the base station 1-2 changes from its own station to another mobile station 3 -2 or the transmission power of the data block of HS-PDSCH to the mobile station 3-4 is controlled (step S98 in FIG. 28). Thereafter, while the difference in the reception quality of each of the base stations 1-1 and 1-2 from the mobile station 3-1 is greater than or equal to a predetermined threshold, the base station 1-2 changes from its own station to another mobile station 3- 2 or the transmission power of the data block of HS-PDSCH to the mobile station 3-4.

  Further, when the mobile station 3-1 receives the last data block (packet #n) from the base station 1-1 (step S 114 in FIG. 29), the mobile station 3-1 receives the data block from the base stations 1-1 and 1-2 during soft handover. A reception end notification is transmitted (step S116 in FIG. 29).

  When receiving the data block reception end notification from the mobile station 3-1 (step S 96 in FIG. 27), the base station 1-1 returns to step S 91 and waits for the next data from the base station controller 2. Further, the base station 1-2 has a difference in reception quality between the base stations 1-1 and 1-2 from the mobile station 3-1 that is equal to or less than a predetermined threshold (step S101 in FIG. 28), and HS-PDSCH. If the transmission power of the data block is being controlled (step S102 in FIG. 28), the control of the transmission power of the data block of HS-PDSCH from the own station to another mobile station 3-2 or 3-4 is canceled. Then (step S103 in FIG. 28), the process returns to step S91 and waits for the next data from the base station controller 2 or the reception quality from the mobile stations 3-1, 3-2 and 3-4.

  In this embodiment, as in the above-described fifth embodiment of the present invention, the base station 1-2 waits for the arrival of the measurement result of the reception quality from the mobile station 3-1, and then the transmission power of the HS-PDSCH data block Since the transmission power of the HS-PDSCH data block is controlled based on the transmission timing information from the mobile station 3-1, even if the interference of the base station 1-2 is large from the beginning, Immediate improvement in throughput can be achieved. The other effects of this embodiment are the same as those of the fifth embodiment of the present invention.

  Here, in the fifth and sixth embodiments of the present invention, the reception quality of the common pilot signal from each of the base stations 1-1 and 1-2 during soft handover measured by the reception quality measuring unit 71 is directly used as a data block. The transmission quality is added to the reception response, and the difference in reception quality between the common pilot signals is calculated by the reception quality notification unit 72, and the calculated value is added to the data block reception response and transmitted. Also good.

It is a block diagram which shows the structure of the mobile communication system by embodiment of this invention. It is a block diagram which shows the structure of the base station by the 1st Example of this invention. It is a block diagram which shows the structure of the mobile station by 1st Example of this invention. It is a sequence chart which shows the transmission timing adjustment process of the data of HS-PDSCH by the 1st Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 1st Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 1st Example of this invention. 3 is a flowchart illustrating HS-PDSCH data reception processing in the mobile station of FIG. 1 according to the first embodiment of the present invention. It is a block diagram which shows the structure of the base station by the 2nd Example of this invention. It is a block diagram which shows the structure of the mobile station by the 2nd Example of this invention. It is a sequence chart which shows the transmission timing adjustment process of the data of HS-PDSCH by the 2nd Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 2nd Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 2nd Example of this invention. 7 is a flowchart illustrating HS-PDSCH data reception processing in the mobile station of FIG. 1 according to a second embodiment of the present invention. It is a sequence chart which shows the transmission timing adjustment process of the data of HS-PDSCH by the 3rd Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 3rd Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 3rd Example of this invention. 7 is a flowchart illustrating HS-PDSCH data reception processing in the mobile station of FIG. 1 according to a third embodiment of the present invention. It is a block diagram which shows the structure of the mobile communication system by the 4th Example of this invention. It is a figure which shows an example of the identification code determined with the base station control apparatus of FIG. It is a block diagram which shows the structure of the base station by the 5th Example of this invention. It is a block diagram which shows the structure of the mobile station by the 5th Example of this invention. It is a sequence chart which shows the transmission timing adjustment process of the data of HS-PDSCH by the 5th Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 5th Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 5th Example of this invention. It is a flowchart which shows the reception process of the data of HS-PDSCH in the mobile station of FIG. 1 by 5th Example of this invention. It is a sequence chart which shows the transmission timing adjustment process of the data of HS-PDSCH by the 6th Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 6th Example of this invention. It is a flowchart which shows the transmission timing adjustment process of the data of HS-PDSCH in the base station of FIG. 1 by 6th Example of this invention. It is a flowchart which shows the reception process of the data of HS-PDSCH in the mobile station of FIG. 1 by 6th Example of this invention.

Explanation of symbols

1, 1-1 to 1-3, 4, 6 Base station 2 Base station controller 3, 3-1 to 3-4, 5, 7 Mobile station 11, 31 Antenna 12, 32 Transmission / reception duplexer 13, 33 Receiver 14, 34 User information / control information separation unit 15 HS-PDSCH data transmission timing detection unit 16, 35, 42, 62 Control unit 17 Modulation / coding unit 18 HS-PDSCH data transmission timing notification unit 19, 38 Combining unit 20, 39 Transmitting unit 20, 30 Recording medium 26 Demodulation / decoding unit 37 HS-PDSCH data transmission timing detection / notification unit 41 Codeword detection unit 51, 71 Reception quality measurement unit 52 Codeword notification unit 61 Reception quality detection unit 72 Reception quality Notification section

Claims (55)

Soft handover is achieved by performing transmission and reception of individual signals between at least a mobile station located near the cell boundary of each of the first and second base stations and each of the first and second base stations, and A mobile communication system in which data transmission is performed from each of the first and second base stations to the mobile station,
The mobile station includes means for notifying the other base station when the data transmission is performed in one of the first and second base stations, and the mobile station transmits the data communication timing information to the other base station. Notify the base station,
The mobile communication system, wherein the base station has control means for controlling its own transmission power when receiving the notification from the mobile station.   The means for notifying the timing information is configured to notify a numerical value indicating the timing of data transmission to the other of the first and second base stations as the timing information. Mobile communication system.   The means for notifying the timing information notifies the other of the first and second base stations as the timing information of a signal notifying that the start timing of the data transmission is after a predetermined time set in advance. The mobile communication system according to claim 1, wherein the mobile communication system is configured as described above.   The mobile communication system according to any one of claims 1 to 3, wherein means for notifying the mobile station of the timing of data transmission is included in each of the first and second base stations.   The mobile communication system according to any one of claims 1 to 4, wherein the control unit is configured to stop the data transmission to the other mobile station.   The mobile communication system according to any one of claims 1 to 6, wherein the control unit is configured to reduce transmission power of the data transmission to the other mobile station.   The control means is configured to control transmission power of the data transmission to the other mobile station until the end of the data transmission is detected based on a notification signal from the mobile station. The mobile communication system according to any one of claims 1 to 6.   Measuring means for measuring the reception quality of the common pilot signal from each of the first and second base stations, and information based on the measurement result of the measuring means to the other of the first and second base stations The notification means for notifying is included in the mobile station, and the control means is configured to control transmission power of the data transmission based on information from the notification means. The mobile communication system according to any one of the above.   The notifying unit is configured to notify the other of the first and second base stations as it is of the reception quality of the common pilot signal from each of the first and second base stations measured by the measuring unit. 9. The mobile communication system according to claim 8, wherein   The notifying means calculates a difference in reception quality of the common pilot signal from each of the first and second base stations measured by the measuring means and calculates the difference between the other one of the first and second base stations. The mobile communication system according to claim 8, wherein notification is made.   The control means reduces the transmission power of the data transmission to the other mobile station when the difference in reception quality of the common pilot signal from each of the first and second base stations is larger than a preset threshold value. The mobile communication system according to claim 9 or 10, wherein the mobile communication system is configured to be controlled.   The notifying means sends a signal for prompting the other of the first and second base stations to control transmission power of the data transmission when it is determined from the measurement result of the measuring means that the interference with the mobile station is large. The mobile communication system according to claim 8, wherein notification is made.   The notifying means determines the other of the first and second base stations when the difference in reception quality of the common pilot signal from each of the first and second base stations is larger than a preset threshold value. The mobile communication system according to claim 12, wherein identification information for identification is notified.   The mobile communication system according to claim 13, wherein the control means is configured to control transmission power of the data transmission to the other mobile station when receiving the identification information.   15. The mobile communication system according to claim 13, wherein the identification information is information for specifying a plurality of base stations.   The said notification means is comprised so that the information notified to the other of the said 1st and 2nd base station may be notified using the said separate signal, The any one of Claims 8-15 characterized by the above-mentioned. Mobile communication system.   The mobile communication system according to any one of claims 1 to 16, wherein the data transmission is performed by an HSDPA (High Speed Downlink Packet Access) method. A base station that implements soft handover by transmitting / receiving individual signals to / from a mobile station located near a cell boundary and transmits data to the mobile station, and the timing of data transmission at another station A base station characterized by comprising control means for controlling the data transmission power in the local station according to the timing information when the information is notified from the mobile station.   The base station according to claim 18, wherein the control means is configured to control transmission power of the data transmission based on a numerical value received as the timing information and indicating a timing of the data transmission.   The control means is configured to control the transmission power of the data transmission based on a signal received as the timing information and notifying that the start timing of the data transmission is after a predetermined time set in advance. The base station according to claim 18.   21. The base station according to claim 18, further comprising means for notifying the mobile station of the timing of data transmission.   The base according to any one of claims 18 to 21, wherein the control means is configured to control transmission power of the data transmission in the local station at the same timing as notified from the mobile station. Bureau.   23. The base station according to claim 22, wherein the control unit is configured to stop the data transmission in the own station.   23. The base station according to claim 22, wherein the control unit is configured to reduce transmission power of the data transmission in the own station. The control means is configured to control transmission power of the data transmission to the other mobile station until the end of the data transmission is detected based on a notification signal from the mobile station. The base station according to any one of claims 22 to 24 .   The control means controls the transmission power of the data transmission based on the information when the information based on the measurement result of the reception quality of the common pilot signal from the local station and the other station is transmitted from the mobile station. The base station according to any one of claims 18 to 25, configured as described above.   27. The control unit according to claim 26, wherein the control means is configured to control the transmission power of the data transmission according to the reception quality when the reception quality of the common pilot signal is directly notified from the mobile station. base station.   The control means is configured to control the transmission power of the data transmission according to the difference in reception quality when the difference in reception quality of the common pilot signal is notified from the mobile station. 26. A base station according to 26.   28. The control unit according to claim 27, wherein the control unit is configured to control transmission power of the data transmission in the local station when a difference in reception quality of the common pilot signal is larger than a preset threshold value. Item 29. The base station according to Item 28.   The control means is notified when the mobile station determines that the interference with the mobile station is large from the measurement result of the reception quality, and according to a signal for prompting transmission power control of the data transmission according to the HSDPA method. 27. The base station according to claim 26, wherein the base station is configured to control transmission power of data transmission.   The control means is notified when the mobile station determines that the difference in reception quality of the common pilot signal is greater than a preset threshold value and responds to identification information for identifying the own station and other stations. The base station according to claim 30, wherein the base station is configured to control transmission power of the data transmission.   32. The base station according to claim 31, wherein the control means is configured to control transmission power of the data transmission in the local station when receiving the identification information.   The base station according to claim 31 or 32, wherein the identification information is information for specifying a plurality of base stations.   The base according to any one of claims 26 to 33, wherein the control means is configured to control transmission power of the data transmission based on information using the individual signal from the mobile station. Bureau.   35. The base station according to claim 18, wherein the data transmission is performed by an HSDPA (High Speed Downlink Packet Access) method. Soft handover is achieved by performing transmission and reception of individual signals between at least a mobile station located near the cell boundary of each of the first and second base stations and each of the first and second base stations, and A packet transmission timing control method for a mobile communication system in which data transmission is performed from each of a first base station and a second base station to the mobile station,
When the data transmission is performed in one of the first and second base stations, the mobile station notifies the other base station of timing information indicating the timing of the data transmission in the one base station. A packet transmission timing control method comprising: a step, wherein a base station that has received the notification controls the data transmission power according to the notified timing information.   37. The step of notifying the timing information is configured to notify a numerical value indicating the timing of data transmission to the other of the first and second base stations as the timing information. Packet transmission timing control method.   The step of notifying the timing information notifies the other of the first and second base stations of the signal for notifying that the start timing of the data transmission is after a predetermined time set in advance as the timing information. The packet transmission timing control method according to claim 36, wherein the packet transmission timing control method is configured as described above. The packet transmission timing control method according to any one of claims 36 to 38 , further comprising a step of notifying the mobile station of the timing of data transmission in each of the first and second base stations.   The step of controlling the data transmission controls transmission power of the data transmission from the other one of the first and second base stations to another mobile station at the same timing as notified from the mobile station. 40. The packet transmission timing control method according to claim 36, wherein the packet transmission timing control method is configured as described above.   The packet transmission timing control method according to claim 40, wherein the step of controlling the data transmission stops the data transmission to the other mobile station.   41. The packet transmission timing control method according to claim 40, wherein said step of controlling data transmission reduces transmission power of said data transmission to said other mobile station. The step of controlling the data transmission controls the transmission power of the data transmission to the other mobile station until the end of the data transmission is detected based on a notification signal from the mobile station. The packet transmission timing control method according to any one of claims 40 to 42 . Measuring the reception quality of the common pilot signal from each of the first and second base stations, and notifying the other one of the first and second base stations of information based on the measurement result; And the step of controlling the data transmission controls the transmission power of the data transmission in the HSDPA scheme based on the information from the step of notifying the information based on the measurement result. The packet transmission timing control method according to any one of claims 35 to 43 , wherein: The step of notifying the information based on the measurement result includes the measured reception quality of the common pilot signal from each of the first and second base stations as it is to the other of the first and second base stations. 45. The packet transmission timing control method according to claim 44 , wherein notification is performed.   The step of notifying the information based on the measurement result calculates a difference in reception quality of the common pilot signal from each of the measured first and second base stations, and calculates the difference between the first and second base stations. 45. The packet transmission timing control method according to claim 44, wherein the other is notified.   The step of controlling the data transmission includes transmitting the data to the other mobile station when a difference in reception quality of a common pilot signal from each of the first and second base stations is larger than a preset threshold value. 47. The packet transmission timing control method according to claim 45 or 46, characterized in that the transmission power is controlled.   The step of notifying the information based on the measurement result includes transmitting power control of the data transmission to the other of the first and second base stations when it is determined from the measurement result that interference with the mobile station is large. 45. The packet transmission timing control method according to claim 44, wherein a signal for prompting is notified.   The step of notifying the information based on the measurement result includes the first and second steps when a difference in reception quality of the common pilot signal from each of the first and second base stations is larger than a preset threshold value. 49. The packet transmission timing control method according to claim 48, wherein identification information for identifying the other of the base stations is notified.   The packet transmission timing according to claim 49, wherein the step of controlling the data transmission controls transmission power of the data transmission to the other mobile station when the identification information is received. Control method.   51. The packet transmission timing control method according to claim 49, wherein the identification information is information for specifying a plurality of base stations.   45. The step of notifying information based on the measurement result notifies the information to be notified to the other of the first and second base stations using the individual signal. 52. The packet transmission timing control method according to claim 51.   53. The packet transmission timing control method according to claim 36, wherein the data transmission is performed by an HSDPA (High Speed Downlink Packet Access) method. Soft handover is achieved by performing transmission and reception of individual signals between at least a mobile station located near the cell boundary of each of the first and second base stations and each of the first and second base stations, and A program of a packet transmission timing control method for a mobile communication system in which data transmission is performed from each of the first and second base stations to the mobile station, the computer comprising:
When data transmission is performed in one of the first and second base stations, the mobile station notifies the other base station of timing information indicating the timing of the data transmission in the one base station. The base station that has received the notification executes a process for controlling the data transmission power in accordance with the notified timing information. 55. The program according to claim 54, wherein the data transmission is performed by an HSDPA (High Speed Downlink Packet Access) method.

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