JP2011166806A - Mobile communication system, base station control device, and mobile terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the circuit size of a receiving circuit in a mobile terminal of which the maximum transmission rate is low. <P>SOLUTION: The maximum number of non-serving base stations selected from among a plurality of base stations by a base station control device 25 is constituted so as to be set according to ability information received from a mobile terminal 21. Thus, if the mobile terminal 21 is a mobile terminal B with a low transmission rate, an effect that reduction of the circuit size of the receiving circuit in the mobile terminal 21 is acquired. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a non-serving having a control function for controlling transmission power of data in a mobile terminal that transmits data and a plurality of base stations that receive macro diversity reception of data transmitted from the mobile terminal. The present invention relates to a base station control device that selects a base station, and a mobile communication system that includes the base station control device and the like.

A mobile terminal in a conventional mobile communication system is configured to transmit data to the base station as soon as the data arrives.
That is, in the conventional mobile communication system, each mobile terminal in the cell is allowed to arbitrarily transmit data.
However, in recent years, the amount of interference of the base station has increased because the power of transmission data in mobile terminals has increased with the increase in transmission data speed.
As a result, when each mobile terminal arbitrarily transmits data, the amount of interference of the base station may exceed the allowable amount and cause communication failure.

Therefore, in a mobile communication system for high-speed packet communication, a scheduler is installed in a base station, and the scheduler controls the transmission rate and transmission power at each mobile terminal, thereby limiting the power transmitted from each mobile terminal simultaneously. Is not exceeded.
That is, the base station scheduler controls the transmission rate, transmission power, etc. of each mobile terminal in consideration of the interference amount of the base station, so that the amount of interference of the base station caused by the data transmission of each mobile terminal is limited. Within the range not exceeding the maximum allowable amount.
Thereby, since radio | wireless resources can be utilized effectively, the accommodation capacity of the mobile terminal in a cell can be increased and the throughput of a mobile communication system can be improved.

  In the conventional mobile communication system, the base station cannot control the amount of interference, and data may be transmitted at a high rate from each mobile terminal at the same time. The maximum transmission rate is limited in anticipation of a certain margin, but if the above-mentioned scheduler can reliably control the interference amount of the base station, the margin is reduced and the transmission peak rate of the mobile terminal is increased. Is also possible.

Here, in uplink transmission of data, data transmitted from a mobile terminal may reach a plurality of base stations, and a base station other than the base station in charge of scheduling can receive the data. .
A process in which a plurality of base stations receive data transmitted from one mobile terminal and improve the quality is called macro diversity. When there are a plurality of base stations that receive data transmitted from one mobile terminal, A base station in charge of scheduling processing for a mobile terminal is called a primary base station or a serving base station.

On the other hand, a base station that is not responsible for scheduling processing but receives data transmitted from a mobile terminal is called a non-serving base station, and a set of a plurality of base stations that communicate with a certain mobile terminal is called an active set. .
However, even if it is a non-serving base station in relation to a certain mobile terminal, the scheduler itself is implemented because it may be necessary to take charge of scheduling processing in relation to other mobile terminals. Whether or not the base station is responsible for scheduling for a specific mobile terminal distinguishes the serving base station and the non-serving base station.

Conventionally, also in uplink transmission of data, macro diversity reception is performed during soft handover, and all base stations that become an active set receive soft links during soft handover.
However, in high-speed packet communication using a scheduler, the target is to reduce the power of transmission data and cover a high error rate with retransmission control with the base station, but all base stations can receive data. In order to achieve this, the mobile terminal transmits data with excessively increased transmission power.
On the other hand, when only the serving base station serving as the scheduler can receive data, if the transmission path quality of the data fluctuates and the transmission path quality deteriorates, many retransmission processes of the data occur. As a result, the throughput decreases.

Even in a mobile communication system configured in consideration of the above points, the scheduler can grasp the amount of interference of a base station in which the scheduler is installed, but the other base stations in which the scheduler is not installed The amount of interference cannot be grasped immediately.
Therefore, even if the interference caused by data transmission by a specific mobile terminal is within the allowable range for the base station where the mobile terminal is installed, the interference is acceptable for other base stations where the mobile terminal is not installed. Can be exceeded.
Therefore, it is desirable that a non-serving base station not in charge of scheduling processing also has a function of controlling the transmission power of data in the mobile terminal.

As a function of controlling the transmission power of data in the mobile terminal, the non-serving base station transmits a Down command requesting to lower the transmission rate to the mobile terminal (the Down command is sent to the E-RGCH ( E-DCH Relative Grant Channel) is used to control the transmission power of data in a mobile terminal (see Non-Patent Document 1 below).
Thereby, the non-serving base station whose interference amount exceeds the allowable amount can control the transmission power of the data transmitted from the mobile terminal and suppress the deterioration of the transmission quality.

Specifically, it is as follows.
For example, a mobile terminal A having a high transmission rate, a mobile terminal B having a low transmission rate, a serving base station SB that performs scheduling for the mobile terminals A and B, and a non-serving base station that does not perform scheduling for the mobile terminals A and B Consider a mobile communication system with NSB.
In the serving base station SB, it is possible to maintain a sufficient interference margin by performing scheduling of the mobile terminal A having a high transmission rate and a large transmission power.

However, since the non-serving base station NSB does not perform scheduling of the mobile terminal A, the interference margin may not be sufficiently maintained at the current transmission rate (transmission power) of the mobile terminal A.
In such a case, the non-serving base station NSB transmits a Down command to the mobile terminal A, thereby reducing the transmission power of the mobile terminal A so as to keep the interference margin sufficiently.
Note that since the mobile terminal B having a low transmission rate has a low transmission power, an increase in the amount of interference due to the power of data transmitted from the mobile terminal B even in the non-serving base station NSB in which the scheduling of the mobile terminal B is not performed. Less.

For example, consider a case where the maximum number of E-DCH active sets (serving base station SB + non-serving base station NSB) is set to “5” in the mobile communication system.
In general, there is one serving base station SB that performs scheduling of a mobile terminal for one mobile terminal.
In this case, the mobile communication system includes a maximum of four non-serving base stations NSB in addition to the serving base station SB.
The serving base station SB in the mobile communication system performs scheduling of the mobile terminal A having a high transmission rate and a large transmission power so as to maintain a sufficient interference margin.
On the other hand, the four non-serving base stations NSB in the mobile communication system transmit the Down command to the mobile terminal A, thereby reducing the transmission power of the mobile terminal A and keeping the interference margin sufficiently.

Accordingly, the mobile terminals A and B in the mobile communication system need to have a receiving circuit configured to receive the Down command from the E-DCH active set base station. That is, it is necessary to configure a receiving circuit that accommodates five E-RGCHs used by one serving base station SB and four non-serving base stations NSB.
In this way, it is necessary to configure the receiving circuits of the mobile terminals A and B by the maximum number of E-DCH active sets, but the mobile terminal B has a low transmission rate, and even if the mobile terminal B transmits data. The influence on the interference margin of the non-serving base station NSB is small.
Therefore, in practice, the non-serving base station NSB rarely transmits a Down command to the mobile terminal B, and there is little need to configure the receiving circuit of the mobile terminal B to be equivalent to the receiving circuit of the mobile terminal A. . The receiving circuits of the mobile terminals A and B will be described in detail in the following embodiment section.

Conventionally, there is a soft handover technique that does not use a scheduler. For example, the optimization of the number of active sets is disclosed in Patent Document 1 below.
Patent Document 1 discloses a method in which a mobile terminal performs wireless communication with a base station, measures signal strength, RF performance, and the like, and adjusts the number of active sets using two thresholds (those that are larger than the first threshold). If there is one, an active set is selected, and if there are more than the second threshold, two active sets are selected (first threshold> second threshold).
However, Patent Document 1 merely discloses a method of limiting the number of active sets by measuring signal strength, RF performance, or the like for the purpose of simply saving radio resources. No reduction is shown.

Further, the technique of high-speed packet communication in which a scheduler is introduced is disclosed in Patent Document 2 below.
Patent Document 2 discloses a method for performing efficient E-DCH (Enhanced DCH) scheduling when mobile terminals located in a soft handover region receive different scheduling commands from a plurality of base stations. ing.
However, Patent Document 2 does not show the reduction of the receiving circuit scale of the mobile terminal.

JP 2002-95031 (paragraph numbers [0010] to [0017], FIG. 1) JP 2004-248300 A (paragraph numbers [0070] to [0090], FIG. 10)

3GPP TS 25.309 V6.3.0 (2005-06)

  Since the conventional mobile communication system is configured as described above, even in a non-serving base station NSB that does not perform scheduling of the mobile terminals A and B, a transmission rate is high by transmitting a Down command to the mobile terminal A. By reducing the transmission power of the mobile terminal A, the interference margin can be kept sufficiently. However, even when mobile terminals A and B having different data transmission capabilities coexist, the maximum number of E-DCH active sets (the maximum number of serving base stations SB + non-serving base stations NSB) is determined in the system. In fact, the mobile terminal B that has a low possibility of receiving a Down command from the non-serving base station NSB (a mobile terminal having a low transmission rate) also forms a reception circuit equivalent to the mobile terminal A. There were issues such as having to.

The present invention has been made to solve the above-described problems, and is to obtain a mobile communication system and a base station control device capable of reducing the circuit scale of a receiving circuit of a mobile terminal having a low maximum transmission rate. Objective.
Another object of the present invention is to obtain a mobile terminal capable of reducing the circuit scale of a receiving circuit.

  In the mobile communication system according to the present invention, the maximum number of non-serving base stations selected by the base station controller is set according to the capability information received from the mobile terminal.

  As a result, the circuit scale of the receiving circuit of the mobile terminal having a low transmission rate can be reduced.

It is a block diagram which shows a mobile communication system in case a mobile terminal receives DCH from several DCH active set base stations. It is a block diagram which shows a mobile communication system in case a mobile terminal receives E-RGCH from an E-DCH active set base station. It is a block diagram which shows the demodulation part in a mobile terminal. It is a conceptual diagram which shows the interference amount and interference margin of a base station. 1 is a configuration diagram showing a mobile communication system according to Embodiment 1 of the present invention. It is a block diagram which shows the mobile terminal by Embodiment 1 of this invention. It is a block diagram which shows the base station control apparatus by Embodiment 1 of this invention. It is a sequence diagram which shows the procedure in which a mobile terminal notifies the maximum number of E-DCH active set, or Capabilities information to a base station control apparatus. It is a sequence diagram in case a mobile terminal mainly performs an E-DCH active set addition (update) process. It is a sequence diagram in case a base station control apparatus mainly performs the addition (update) process of an E-DCH active set. It is explanatory drawing which shows the capability (UE Capabilities) of the mobile terminal regarding E-DCH standardized by the 3GPP specification. It is explanatory drawing which shows the example of a correspondence with Capabilities information and the maximum number of E-DCH active sets. It is a detailed block diagram which shows the modulation part of the mobile terminal at the time of multicode. It is explanatory drawing which shows the Capabilities assumption table | surface regarding E-DCH in case the mobile communication system prepares the maximum number of E-DCH active sets.

Hereinafter, in order to explain the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
In FIG. 1, a mobile terminal receives a DCH (DCH is an abbreviation of “Dedicated Channel”) from a DCH active set base station, and DCH is a channel through which data is exchanged individually. FIG. 2 is a configuration diagram showing a mobile communication system in a case where a mobile communication system is received.
Here, the DCH active set base station is a plurality of base stations that receive macro diversity DCH data from a mobile terminal in order to perform soft handover.

  The mobile communication system of FIG. 1 is disclosed in the 3GPP standard (3GPP R'99), which is a non-patent document. The mobile terminal 1 receives DCH from a plurality of DCH active set base stations 2a and 2b in order to perform soft handover, but the DCH transmitted from the plurality of DCH active set base stations 2a and 2b is The same data. Further, the DCH active set base stations 2a and 2b adjust the DCH transmission timing when the mobile terminal 1 arrives. As a result, soft combine can be implemented, and the RAKE synthesis unit and the like can be constructed with a single system configuration.

Here, a method for adjusting the DCH transmission timing by the DCH active set base stations 2a and 2b will be described in detail.
For simplification of explanation, FIG. 1 shows a case where two DCH active set base stations 2a and 2b, which are DCH soft handover base stations, are allocated. It is possible to allocate DCH active set base stations.

In the W-CDMA system, base stations operate asynchronously.
That is, the DCH transmitted and received between the DCH active set base station 2a and the mobile terminal 1 is delayed from the reference timing of the DCH active set base station 2a (for example, the transmission timing of CPICH (Common Pilot Channel) which is a common pilot channel). It is transmitted at a timing delayed by ΔTa (the delay amount ΔTa is determined for each individual mobile terminal 1).

For example, when the mobile terminal 1 receives DCH from a plurality of DCH active set base stations 2a and 2b at the time of soft handover, the DCH active set base station 2a, for example, determines the CPICH of the DCH active set base station 2a in advance. The transmission timing and the delay amount ΔTa are reported to the base station control device 3.
When the base station controller 3 receives a report of the CPICH transmission timing and the delay amount ΔTa from the DCH active set base station 2a, the base station control device 3 uses the CPICH transmission timing and the delay amount ΔTa as a soft handover destination. Notify the station 2b.
When the DCH active set base station 2b receives the CPICH transmission timing and the delay amount ΔTa from the base station controller 3, the DCH active set base station 2b refers to the CPICH transmission timing and the delay amount ΔTa and transmits the CPICH transmission set and the delay amount ΔTa. The DCH active set base station 2b is determined by determining the delay amount ΔTb determined for each individual mobile terminal 1 so that the DCH to be transmitted and the DCH transmitted by itself are received at the same timing as possible in the mobile terminal 1. The DCH is transmitted at a timing delayed by a delay amount ΔTb from the reference timing.
Thereby, even when a plurality of DCH active set base stations 2a and 2b transmit DCH to the mobile terminal 1, when the mobile terminal 1 receives the DCH, the configuration such as RAKE combining in the DCH demodulation unit of the mobile terminal 1 is 1 It can be constructed with a system configuration.

FIG. 2 is a block diagram showing a mobile communication system when a mobile terminal receives E-RGCH from an E-DCH active set base station.
E-RGCH is an abbreviation for “E-DCH Relative Grant Channel”, and E-RGCH is a downlink channel that transmits a request (Down command) to reduce the transmission rate of an uplink high-speed packet (E-DCH). Are transmitted from the non-serving base stations 12-1 and 12-2 to the mobile terminal 1. The mobile terminal 1 is also transmitted from the serving base station 11.

The serving base station 11 is responsible for scheduling processing for the mobile terminal 1 and controls the transmission rate, transmission power, etc. in the mobile terminal 1 so that the power transmitted simultaneously from the plurality of mobile terminals 1 does not exceed the limit. It is a base station. In FIG. 2, only one mobile terminal 1 is shown, but usually there are a plurality of mobile terminals 1.
The non-serving base stations 12-1 and 12-2 are not in charge of scheduling processing, but control the transmission power of data in the mobile terminal 1 by transmitting to the mobile terminal 1 a Down command requesting to lower the transmission rate. It is a base station with a function.

  In the example of FIG. 2, base stations corresponding to the DCH active set base stations 2a and 2b of FIG. 1 are not shown, but the serving base station 11 and the non-serving base stations 12-1 and 12-2 The base station of the DCH active set that receives macro diversity data transmitted from the mobile station, that is, the base station corresponding to the DCH active set base stations 2a and 2b in FIG. In other words, the DCH active set base station can be the serving base station 11 or the non-serving base stations 12-1 and 12-2.

E-DCH (Enhanced DCH) is a data channel that performs high-speed packet communication in the uplink.
E-AGCH (E-DCH Absolute Grant Channel) is a downlink channel that determines a transmission rate of an uplink high-speed packet (E-DCH), and is transmitted from the serving base station 11 to the mobile terminal 1.
The E-HICH (E-DCH Hybrid ARQ Indicator Channel) transmits an ACK / NACK signal for notifying the success or failure of E-DCH reception in the serving base station 11 and the non-serving base stations 12-1 and 12-2. Is a channel.
The E-DCH data received by macro diversity by the serving base station 11 and the non-serving base stations 12-1 and 12-2 is transmitted to the base station controller 3.

FIG. 3 is a configuration diagram showing a demodulation unit in the mobile terminal 1. The overall configuration of the mobile terminal 1 in FIG. 6 will be described later.
In FIG. 3, when the frequency converter 201 amplifies an RF signal (Radio Frequency) including a multipath signal that is a weak radio signal received by the antenna 114 by the low noise amplifier 115 of FIG. 6, the frequency of the RF signal To output a signal after frequency conversion.
The A / D converter 202 converts the frequency-converted signal that is an analog signal output from the frequency converter 201 into a digital signal.

When receiving the E-RGCH transmitted from the serving base station 11 and receiving the digital signal from the A / D converter 202, the search unit 203-1 performs the cell search process to receive the multipath. A serving base station 11 that is a base station of a signal transmission source is detected.
The code generator 204-1 generates a scrambling code corresponding to the serving base station 11 detected by the search unit 203-1.

The finger assignment control unit 205-1 assigns a digital signal (hereinafter referred to as a digital signal A-1) related to the first multipath signal transmitted from the serving base station 11 to the finger unit 206a-1, The RAKE combining unit 206-1 is controlled so that a digital signal related to the multipath signal (hereinafter referred to as a digital signal A-2) is assigned to the finger unit 206b-1.
Here, for simplification of explanation, a digital signal is not assigned to the finger portions 206c-1 and 206d-1, but for example, a digital signal related to the third multipath signal is assigned to the finger portion 206c-1. Needless to say, the digital signal related to the fourth multipath signal may be assigned to the finger portion 206d-1.

When receiving the E-RGCH received from the non-serving base station 12-1, the search unit 203-2 receives a digital signal from the A / D conversion unit 202, and performs a cell search process. The non-serving base station 12-1, which is the base station that is the transmission source of the multipath signal, is detected.
The code generator 204-2 generates a scrambling code corresponding to the non-serving base station 12-1 detected by the search unit 203-2.

The finger assignment control unit 205-2 assigns a digital signal (hereinafter referred to as digital signal B-1) related to the first multipath signal transmitted from the non-serving base station 12-1 to the finger unit 206a-2, and The RAKE combining unit 206-2 is controlled so that a digital signal related to the second multipath signal (hereinafter referred to as digital signal B-2) is assigned to the finger unit 206b-2.
Here, for simplification of description, a digital signal is not assigned to the finger portions 206c-2 and 206d-2. For example, a digital signal related to the third multipath signal is assigned to the finger portion 206c-2. Needless to say, the digital signal related to the fourth multipath signal may be assigned to the finger portion 206d-2.

When the search unit 203-3 receives the E-RGCH received from the non-serving base station 12-2 and receives a digital signal from the A / D conversion unit 202, the search unit 203-3 performs a cell search process, The non-serving base station 12-2, which is the base station that is the transmission source of the multipath signal, is detected.
The code generator 204-3 generates a scrambling code corresponding to the non-serving base station 12-2 detected by the search unit 203-3.

The finger assignment control unit 205-3 assigns a digital signal (hereinafter referred to as a digital signal C-1) related to the first multipath signal transmitted from the non-serving base station 12-3 to the finger unit 206a-3, and The RAKE combining unit 206-3 is controlled so that a digital signal related to the second multipath signal (hereinafter referred to as a digital signal C-2) is assigned to the finger unit 206b-3.
Here, for simplification of description, a digital signal is not assigned to the finger portions 206c-3 and 206d-3. For example, a digital signal related to the third multipath signal is assigned to the finger portion 206c-3. Needless to say, the digital signal related to the fourth multipath signal may be assigned to the finger unit 206d-3.

The finger units 206a-1 to 206d-1 of the RAKE combining unit 206-1 use the scrambling code generated by the code generator 204-1 to extract the digital signal assigned by the finger assignment control unit 205-1. Then, the digital signal is output to the cell synthesis unit 206e-1.
The cell combining unit 206e-1 of the RAKE combining unit 206-1 performs a maximum ratio combining process between the digital signal A-1 output from the finger unit 206a-1 and the digital signal A-2 output from the finger unit 206b-1. carry out.

The finger units 206a-2 to 206d-2 of the RAKE combining unit 206-2 use the scrambling code generated by the code generator 204-2 to extract the digital signal allocated by the finger allocation control unit 205-2. Then, the digital signal is output to the cell synthesis unit 206e-2.
The cell combining unit 206e-2 of the RAKE combining unit 206-2 performs a maximum ratio combining process between the digital signal B-1 output from the finger unit 206a-2 and the digital signal B-2 output from the finger unit 206b-2. carry out.

The finger units 206a-3 to 206d-3 of the RAKE combining unit 206-3 use the scrambling code generated by the code generator 204-3 to extract the digital signal allocated by the finger allocation control unit 205-3. Then, the digital signal is output to the cell synthesis unit 206e-3.
The cell combining unit 206e-3 of the RAKE combining unit 206-3 performs maximum ratio combining processing of the digital signal C-1 output from the finger unit 206a-3 and the digital signal C-2 output from the finger unit 206b-3. carry out.

Decoding section 207-1 decodes the combined signal that has been subjected to maximum ratio combining by cell combining section 206e-1, and outputs the decoded signal to E-RGCH receiving circuit 119-1 of E-RGCH receiving section 119.
Decoding section 207-2 decodes the combined signal that has been subjected to maximum ratio combining by cell combining section 206e-2, and outputs the decoded signal to E-RGCH receiving circuit 119-2 of E-RGCH receiving section 119.
Decoding section 207-3 decodes the combined signal that has been subjected to the maximum ratio combining by cell combining section 206e-3, and outputs the decoded signal to E-RGCH receiving circuit 119-3 of E-RGCH receiving section 119.

Here, a case where the mobile terminal 1 receives the E-RGCH from the serving base station 11 and the non-serving base stations 12-1 and 12-2 that are E-DCH active set base stations will be described.
FIG. 4 is a conceptual diagram showing the interference amount and interference margin of the base station. Thermal noise is unavoidable noise that depends on temperature, and other cell interference is interference amount from other base stations. However, the base station cannot distinguish between thermal noise and other cell interference.
The interference margin is obtained by subtracting the total reception power from the uplink reception allowable power.
The parts indicated by UE1 to UE3 (UE is an abbreviation of “User Equipment” and UE means a terminal) are obtained by demodulating a signal transmitted from the mobile terminal 1 with a spreading code in its own base station. Received power (code power).

The base station (serving base station 11 or non-serving base stations 12-1 and 12-2) whose interference amount exceeds the allowable amount transmits a Down command requesting to lower the transmission rate to the mobile terminal 1. As a result, the transmission power of data in the mobile terminal 1 is controlled to ensure a margin of interference margin.
However, in the serving base station 11 and the non-serving base stations 12-1 and 12-2, there is a problem that interference margins are tightened independently for each base station.
Therefore, the contents of the Down command transmitted by the base station (serving base station 11 or non-serving base stations 12-1 and 12-2) whose interference amount exceeds the allowable amount are different for each base station.
Thus, since the contents of the Down command are different for each base station, soft combine cannot be performed, and RAKE combining units 206 and the like are required for the number of E-RGCHs.

The E-RGCH to which the serving base station 11 and the non-serving base stations 12-1 and 12-2 transmit the Down command is a serving serving as an E-DCH active set base station, unlike the DCH that handles data such as voice. Timing adjustment when the mobile terminal 1 arrives is not performed between the base station 11 and the non-serving base stations 12-1 and 12-2.
Therefore, it may be considered that E-RGCH transmitted from a plurality of base stations arrives simultaneously.
Since the mobile terminal 1 cannot control the arrival timing of the E-RGCH transmitted from the serving base station 11 and the non-serving base stations 12-1 and 12-2, the decoding unit 207 and the like also perform time division processing. Difficult to do.

In the example of FIG. 2, the number of E-DCH active set base stations is three. However, when the number of E-DCH active set base stations increases, the E-RGCH of the E-RGCH that the mobile terminal 1 must receive is increased. The number increases.
If the number of E-DCH active set base stations is three, as shown in FIG. 3, three systems of RAKE combining units 206-1, 206-2, 206-3, etc. in the demodulating unit of mobile terminal 1 are implemented. However, when the number of E-DCH active set base stations increases, the number of systems such as RAKE combining units increases by the increase. That is, when the number of E-DCH active set base stations increases from 3 to 3 + N, the number of systems such as RAKE combining units increases to 3 + N.

Thus, in terms of the degree of influence on the hardware implementation of the mobile terminal 1, the degree of influence is greater when the number of base stations of the E-DCH active set is increased than when the number of DCH active set base stations is increased. Can be said to be large.
As a result, even in the low-performance mobile terminal B with a low maximum transmission rate, the down command reception hardware (E-RGCH reception hardware) that is rarely used is the same scale as the high-performance mobile terminal A. The problem of needing to be implemented becomes clear.

Further, as described above, the E-HICH is a channel for transmitting an ACK / NACK signal for notifying the success or failure of E-DCH reception in the serving base station 11 and the non-serving base stations 12-1 and 12-2. It is.
For this reason, E-HICH data transmitted from the serving base station 11 and the non-serving base stations 12-1 and 12-2 are also different for each base station.
Thus, since the content of E-HICH data differs for each base station, soft combining cannot be performed, and RAKE combining units 206 and the like are required for the number of E-HICHs.

Also, the E-HICH transmitted from the serving base station 11 and the non-serving base stations 12-1 and 12-2 is a serving base station that is an E-DCH active set base station, unlike the DCH that handles data such as voice. 11 and the non-serving base stations 12-1 and 12-2 are not adjusted in timing when the mobile terminal 1 arrives.
Therefore, it may be considered that E-HICH transmitted from a plurality of base stations arrives at the same time.
Since the mobile terminal 1 cannot control the arrival timing of the E-HICH transmitted from the serving base station 11 and the non-serving base stations 12-1 and 12-2, the decoding unit 207 and the like also perform time division processing. Difficult to do.

Therefore, in the first embodiment, even if the number of base stations in the E-DCH active set increases, the base station controller 3 selects the low-performance mobile terminal B so that the hardware scale does not increase. A plurality of maximum non-serving base stations (maximum number of E-DCH active sets) are prepared. That is, among the base stations of the DCH active set, a plurality of base stations that can be non-serving base stations are prepared in a plurality of ways, and each mobile terminal 1 constituting the mobile communication system has the capability of the mobile terminal 1. Accordingly, the maximum number of E-DCH active sets is set as the eigenvalue.
That is, a large value is set as the maximum number of non-serving base stations for the mobile terminal A with high capability, and a small value is set as the maximum number of non-serving base stations for the mobile terminal B with low capability. I have to.

FIG. 5 is a block diagram showing a mobile communication system according to Embodiment 1 of the present invention.
In the figure, the mobile terminal 21 is set in advance with the maximum number of E-DCH active sets (the maximum number of base stations that can be its own non-serving base station) in accordance with its own capability. Is a terminal such as a mobile phone or a mobile PC having a function of explicitly or implicitly notifying the base station control device 25 of the maximum number of.
Note that the maximum number of E-DCH active sets for the mobile terminal 21 is a unique value of the mobile terminal 21 and is set independently from the maximum number of non-serving base stations for other mobile terminals 21 not shown. Yes.

Similar to the serving base station 11 of FIG. 2, the serving base station 22 is responsible for scheduling processing for the mobile terminal 21 and controls the transmission rate and transmission power at the mobile terminal 21 to transmit simultaneously from the plurality of mobile terminals 21. It is a base station that prevents the power to be exceeded from exceeding the limit.
The control of the transmission power here refers to controlling the transmission permission power of the mobile terminal 21 by instructing the maximum transmission rate to the mobile terminal 21, and is not the power control in the high-speed closed loop.
The non-serving base station 23 is not in charge of scheduling processing like the non-serving base stations 12-1 and 12-2 of FIG. 2, but transmits a Down command requesting to lower the transmission rate to the mobile terminal 21. This is a base station having a function of controlling the transmission power of data in the mobile terminal 21.

  In the same way as the DCH active set base stations 2a and 2b in FIG. 1, the DCH active set base station 24 performs DCH transmission / reception with the mobile terminal 21, thereby cooperating with the serving base station 22 and the non-serving base station 23. Macro diversity reception of data transmitted from the mobile terminal 21 is performed, but reception of E-DCH is not performed. For this reason, E-DCH becomes interference in the DCH active set base station 24.

The DCH active set base station 24 can be a non-serving base station under the condition that the maximum number of E-DCH active sets for the mobile terminal 21 is not exceeded. It may be changed to a non-serving base station when instructed.
Thus, the base station included in the E-DCH active set is selected from the base stations included in the DCH active set (in this case, the DCH active set base station 24) for the following reason. It is.
The uplink channel is synchronized with the pilot included in the DPCCH (Dedicated Physical Control Channel), and the phase reference of the signal is determined using the pilot, so the base station must be included in the DCH active set. This is because the E-DCH cannot be received.

The base station controller 25 makes these base stations 22, 23, and 24 serve as a serving base station, a non-serving base station, or a DCH active set base station (DCH soft hand) according to the data reception status in the base stations 22, 23, and 24. To the base station).
That is, the base station controller 25 has a function of selecting a base station to be a non-serving base station under the condition that the maximum number of non-serving base stations for the mobile terminal 21 is not exceeded.
In the example of FIG. 5, the base station 23 is selected as a non-serving base station, and the base station 24 is not selected as a non-serving base station.
In this case, the combination of the serving base station 22 and the non-serving base station 23 becomes an E-DCH active set.

FIG. 6 is a block diagram showing the mobile terminal 21 according to the first embodiment of the present invention. In the figure, the control unit 101 controls each processing unit in the mobile terminal 21 and transfers data and parameters. .
When the transmission buffer 102 receives data input by the user from the control unit 101, the transmission buffer 102 performs processing for temporarily holding the data.

  The DPCH transmission unit 103 displays data held in the transmission buffer 102 and events output from the protocol processing unit 130 (for example, the maximum number of E-DCH active sets and Capabilities information indicating the capability of the mobile terminal 21). A process of transmitting the DCH on the DCH is performed. DPCH (Dedicated Physical Channel) is a name of a physical layer for carrying DCH, and means a channel including all actually transmitted data including pilot signals and power control commands in addition to DCH data.

The power management unit 104 includes the DCH power output from the DPCH transmission unit 103, the AG (Absolute Grant) received by the E-AGCH reception unit 118, and the RG (Relateive Grant) received from the E-RGCH reception unit 119. The process which calculates the electric power which can be used for E-DCH from these is implemented.
The AG directly indicates the permitted transmission power transmitted from the serving base station 22 to the mobile terminal 21 as an absolute value based on the result of the scheduler.
The RG instructs the mobile terminal 21 to increase or decrease the permitted transmission power relatively.
In addition, the serving base station 21 can instruct three types: increase of permitted transmission power, maintenance of current status (DTX), and decrease.
The non-serving base station 22 can give two types of instructions: maintaining the current state (DTX) and lowering. This down instruction is a Down command.

The transmission rate control unit 105 performs processing for controlling output of data held in the transmission buffer 102 under the instruction of the scheduler in the serving base station 21.
Also, the transmission rate control unit 105 controls the remaining power of the mobile terminal 21 calculated by the power management unit 104 and the allowable power of E-DCH given from the SG (Serving Grant: scheduler) output from the SG management unit 128. E-TFCI (E-DCH Transport Format Combination Indicator) is calculated from the value to be encoded), and information on the E-DCH transport block size and modulation scheme on the transmitting side is encoded and put into E-TFCI (control bits) Perform the process. On the receiving side, the transport block size and modulation scheme are acquired based on E-TFCI (control bits), and demodulation and decoding processing are performed.

The HARQ processing unit 106 performs a process of determining a ratio between systematic bits that are transmission data information and parity bits that are redundant bits.
The scheduling request information creation unit 107 performs processing for creating scheduling request information from the data output from the transmission buffer 102 and the power that can be used for the E-DCH calculated by the power management unit 104.

The encoder unit 108 mixes systematic bits (information bits) and parity bits (error correction bits) based on RV (Redundancy Version) information output from the retransmission control unit 110, and encodes the mixed result. carry out. RV is information indicating a combination of systematic bits and parity bits.
The E-DCH transmission unit 109 considers the RV information output from the retransmission control unit 110 and performs a process of setting the E-DCH on a physical channel so that transmission is possible.

The retransmission control unit 110 performs a process of calculating RV and RSN (Retransmission Sequence Number) from ACK / NACK information received by the E-HICH reception unit 127. RSN is information indicating the number of retransmissions.
The E-DPCCH transmission unit 111 includes an E-TFCI (control bit) calculated by the transmission rate control unit 105, scheduling request information generated by the scheduling request information generation unit 107, and an RSN output from the retransmission control unit 110. Is encoded into a transmittable form.

The modulation unit 112 multiplexes the signals of the respective channels and then spreads the signals to modulate the desired carrier wave.
The power amplifying unit 113 performs processing for amplifying the carrier wave output from the modulating unit 112 to a desired power.
The antenna 114 transmits a modulated signal, which is a carrier wave amplified by the power amplifier 113, to the serving base station 22, the non-serving base station 23, and the DCH active set base station 24, while the serving base station 22, the non-serving base station 23, and A modulated signal that is a carrier wave transmitted from the DCH active set base station 24 is received.
The DPCH transmission unit 103, the modulation unit 112, the power amplification unit 113, the antenna 114, and the protocol processing unit 130 constitute a maximum number notification unit or a capability notification unit.

The low noise amplifying unit 115 performs processing for amplifying a weak modulated signal received by the antenna 114 to a level necessary for demodulation.
The demodulator 116 despreads the modulated signal amplified by the low noise amplifier 115 (despread with the same code as the code spread at the transmission source) and separates it into the original channel signal.

CPICH reception unit 117 performs reception processing for the common pilot channel and outputs the reception level of the common pilot channel to protocol processing unit 130.
The E-AGCH receiving unit 118 performs processing for receiving AG from the serving base station 22.
The E-RGCH receiving unit 119 performs processing for receiving RG from the serving base station 22 or the non-serving base station 23.
Note that as many E-RGCH receivers 119 as the maximum number of E-DCH active sets are prepared.
The E-AGCH receiving unit 118, the E-RGCH receiving unit 119, the power management unit 104, and the transmission rate control unit 105 constitute power adjustment means.

The DPCH receiving unit 120 performs processing for receiving DCH.
The P-CCPCH receiving unit 121 performs a process of receiving broadcast information.
P-CCPCH is an abbreviation for “Primary Common Control Physical Channel”.

The DCH active set management unit 122 performs processing for confirming the state of the current active set (DCH active set different from the E-DCH active set) from the broadcast information received by the P-CCPCH receiving unit 121.
The DCH active set control unit 123 acquires the interference amount of each base station from the P-CCPCH reception unit 121, the E-AGCH reception unit 118, and the like, and the interference amount of each base station and the current state confirmed by the DCH active set management unit 122 The control content of the DCH active set is determined from the state of the active set, and the control content is output to the protocol processing unit 130.

The E-DCH active set management unit 124 acquires the current E-DCH active set state from the P-CCPCH receiving unit 121 or the E-DCH active set control unit 126, and follows the instruction of the E-DCH active set control unit 126. To update the current active set.
Correlation calculation section 125 calculates the correlation of CPICH power that is the common pilot channel received by CPICH reception section 117, and outputs the correlation of CPICH power to E-DCH active set control section 126.

  The E-DCH active set control unit 126 obtains Capabilities information indicating the maximum number of E-DCH active sets or the capability of the mobile terminal 21 by the protocol processing unit 130, and the P-CCPCH receiving unit 121 and the E-AGCH. While acquiring the interference amount of each base station from the receiving unit 118 and the like, the current E-DCH active set state is acquired from the E-DCH active set management unit 124, and the SG is acquired from the SG management unit 128. The control content of the active set of E-DCH is determined, and the control content is output to the protocol processing unit 130.

The E-HICH receiving unit 127 performs a process of receiving an ACK / NACK signal indicating whether the serving base station 22 and the non-serving base station 23 have received the E-DCH. Note that as many E-HICH receiving units 127 as the E-DCH active sets are prepared.
The SG management unit 128 performs processing for updating the SG based on the AG received by the E-AGCH reception unit 118, the RG received by the E-RGCH reception unit 119, and the like.

The storage unit 129 stores the maximum number of E-DCH active sets, or Capabilities information indicating the capability of the mobile terminal 21 used by the base station controller 25 to set the maximum number of E-DCH active sets. The storage unit 129 constitutes a maximum number storage unit.
The storage unit 129 may be an internal memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory) in the mobile terminal 21, or a SIM card (Subscriber Identity Module) inserted into the mobile terminal 21 from the outside. Such an external memory may be used.
Further, Capabilities information indicating the maximum number of E-DCH active sets recorded in the SIM card and the capability of the mobile terminal 21 may be read, and the read contents may be written to the internal RAM of the mobile terminal 21. .

Capabilities information indicating the maximum number of E-DCH active sets and the capability of the mobile terminal 21 is a unique value of the mobile terminal 21 and may be a single value or a plurality of values.
In addition, the storage unit 129 stores Capabilities information indicating the maximum number of E-DCH active sets and the capability of the mobile terminal 21 in the following form.

As a first method, Capabilities information indicating the maximum number of E-DCH active sets or the capability of the mobile terminal 21 is stored in the storage unit 129 of the mobile terminal 21 as an initial value.
Second, it is stored in the storage unit 129 of the mobile terminal 21 by being acquired from the base station control device 25, the base stations 22, 23, 24, or other devices of the mobile communication system. There is.

Third, the initial value stored in the storage unit 129 of the mobile terminal 21 is processed by, for example, the protocol processing unit 130 of the mobile terminal 21, and the processing result is the maximum number of E-DCH active sets or the mobile terminal. As Capabilities information indicating 21 capabilities, there is a form stored in the storage unit 129 of the mobile terminal 21.
At this time, the initial value stored in the storage unit 129 of the mobile terminal 21 is transmitted to the base stations 22, 23, 24, the base station control device 25, or other devices, and the base stations 22, 23, 24, The base station control device 25 or other device processes the initial value, and the processing result is stored in the storage unit 129 of the mobile terminal 21 as Capabilities information indicating the maximum number of E-DCH active sets or the capability of the mobile terminal 21. It may be stored in the form.

The capability information indicating the maximum number of E-DCH active sets stored in the storage unit 129 or the capability of the mobile terminal 21 is referred to by the protocol processing unit 130 as necessary.
The protocol processing unit 130 is unique when the current number of E-DCH active sets is smaller than the maximum number of E-DCH active sets stored in the storage unit 129 or from Capabilities information indicating the capability of the mobile terminal 21. If the number is less than the maximum number of E-DCH active sets set to, the non-serving base station addition request is generated. In addition, when the current number of E-DCH active sets is greater than or equal to the maximum number of E-DCH active sets stored in the storage unit 129, or is uniquely set from Capabilities information indicating the capability of the mobile terminal 21. If the number is equal to or greater than the maximum number of active E-DCH active sets, update request generation processing for a non-serving base station is performed.
The protocol processing unit 130 is a processing unit that performs communication protocol processing.
The DPCH transmission unit 103, the modulation unit 112, the power amplification unit 113, the antenna 114, and the protocol processing unit 130 constitute additional update request means.

FIG. 7 is a block diagram showing the base station control device 25 according to the first embodiment of the present invention. In the figure, the control unit 301 performs processing for controlling each processing unit of the base station control device 25.
The transmission control unit 302 performs transmission control processing for performing an error-free data link.
The radio resource management unit 303 manages radio resources such as frequencies and codes, and manages the amount of interference and load.

The interference amount storage unit 304 performs processing for storing the interference amounts of the base stations 22, 23, and 24 being served thereby.
The path loss storage unit 305 performs a process of storing the path loss between the mobile terminal 21 and the base stations 22, 23, 24 known by the base stations 22, 23, 24 being served thereby.
The DCH active set management unit 306 performs a process of managing which base station is currently a base station of the DCH active set among the base stations 22, 23, and 24 being served thereby.
The DCH active set control unit 307 determines which base station is included in the DCH active set, and performs control to include any base station in the DCH active set.

The signaling load storage unit 308 performs processing for storing the number of signaling measured by the bases 22, 23, and 24.
For each mobile terminal 21 in which the base station controller 25 is serving RNC (serving RNC is a base station controller in charge of management of a specific mobile terminal), the maximum number storage unit 309 is associated with the E of the mobile terminal 21. -Perform a process to store the maximum number of DCH active sets.
The maximum number storage unit 309 stores the maximum number of E-DCH active sets in the form shown below.

As a first method, the maximum number of E-DCH active sets stored in the mobile terminal 21 is stored by being transmitted from the mobile terminal 21 via the bases 22, 23, and 24. In this case, the maximum number storage unit 309 constitutes a maximum number acquisition unit.
Second, Capabilities information stored in the mobile terminal 21 is transmitted from the mobile terminal 21 via the bases 22, 23, and 24, and other processing of the radio resource management unit 303 or the base station control device 25 is performed. There is a form in which the maximum number is stored by the unit uniquely setting the maximum number of E-DCH active sets from the Capabilities information. In this case, the radio resource management unit 303 constitutes a maximum number setting unit.

The E-DCH active set management unit 310 performs a process of managing which base station is currently an E-DCH active set base station among the base stations 22, 23, and 24 being served thereby.
The E-DCH active set control unit 311 sets the maximum number of E-DCH active sets stored in the maximum number storage unit 309 as an upper limit, and is included in an additional event or update event transmitted from the mobile terminal 21. Control for including the base station indicated by the base station designation information in the active set of the E-DCH is performed.
The E-DCH active set control unit 311 constitutes a non-serving base station selection unit.

FIG. 8 is a sequence diagram showing a procedure in which the mobile terminal 21 notifies the base station controller 25 of the maximum number of E-DCH active sets or Capabilities information.
FIG. 9 is a sequence diagram in the case where the mobile terminal 21 actively performs an E-DCH active set addition (update) process.

Next, the operation will be described.
The storage unit 129 of the mobile terminal 21 stores the maximum number of E-DCH active sets set according to the capability of the mobile terminal 21.
The maximum number of E-DCH active sets stored in the storage unit 129 of the mobile terminal 21 is unique to each mobile terminal. If the mobile terminal 21 has a high performance that supports a high rate, for example, For example, if the maximum number of E-DCH active sets is set to “5” and the mobile terminal B has a low performance that always transmits only at a low rate, the maximum number of E-DCH active sets is set to “3”. Is done.
Here, the maximum number of E-DCH active sets is stored in the storage unit 129 of the mobile terminal 21, but Capabilities information indicating the capability of the mobile terminal 21 is used instead of the maximum number of E-DCH active sets. It may be stored.

The protocol processing unit 130 of the mobile terminal 21 acquires the maximum number of E-DCH active sets or Capabilities information from the storage unit 129 and temporarily stores the maximum number of E-DCH active sets or Capabilities information in the transmission buffer 102. To do.
When the protocol processing unit 130 stores the maximum number of E-DCH active sets or Capabilities information in the transmission buffer 102, the DPCH transmission unit 103 of the mobile terminal 21 stores the maximum number of E-DCH active sets stored in the transmission buffer 102. The number or Capabilities information is put on the DCH, and the DCH is transmitted (step ST1).
However, the maximum number of E-DCH active sets or a channel used for propagation of Capabilities information may be an uplink channel other than DCH.

When the DPCH transmission unit 103 performs the DCH transmission process, the modulation unit 112 of the mobile terminal 21 uses the channel signal after transmission processing (the signal on which the maximum number of E-DCH active sets or Capabilities information is superimposed), for example, It multiplexes with the other channel signal output from the E-DCH transmission part 109, spread | diffuses, and modulates to a desired carrier wave.
When receiving the carrier wave from the modulation unit 112, the power amplifying unit 113 of the mobile terminal 21 performs processing to amplify the carrier wave to a desired power.
The antenna 114 transmits the modulated signal, which is a carrier wave amplified by the power amplification unit 113, to the serving base station 22, the non-serving base station 23, and the DCH active set base station 24, and thereby the modulated signal is transmitted to the base station control device 25. Send to.

When the transmission control unit 302 of the base station controller 25 receives the modulated signal transmitted from the mobile terminal 21 via the base station, the transmission control unit 302 demodulates the modulated signal, and the maximum number of E-DCH active sets or Capabilities information is obtained. The superimposed channel signal is output to the radio resource management unit 303.
If the channel signal output from the transmission control unit 302 is a channel signal on which the maximum number of E-DCH active sets is superimposed, the radio resource management unit 303 of the base station control device 25 will perform the E-DCH active set. Is stored in the maximum number storage unit 309 as it is.

On the other hand, if the channel signal output from the transmission control unit 302 is a channel signal on which Capabilities information is superimposed, the maximum number of E-DCH active sets is set uniquely from the Capabilities information, and the maximum number is set to the maximum. The number is stored in the number storage unit 309 (step ST2).
For example, when the Capabilities information indicates that the mobile terminal 21 has high capability and supports a high rate, the maximum number of E-DCH active sets is set to “5”, and the Capabilities information is the mobile terminal 21. If the capacity of the E-DCH is low and indicates that the high-speed rate is not supported, the maximum number of E-DCH active sets is set to “3”.

  Note that even if the channel signal output from the transmission control unit 302 is a channel signal on which Capabilities information is superimposed, the radio resource management unit 303 stores the Capabilities information as it is in the maximum number storage unit 309, which will be described later. When the maximum number of E-DCH active sets is confirmed by the DCH active set control unit 311, the maximum number of E-DCH active sets may be set from the Capabilities information stored in the maximum number storage unit 309. .

  In the example of FIG. 8, the mobile terminal 21 notifies the base station control device 25 of the maximum number of E-DCH active sets or Capabilities information. For example, the base station control device 25 increases the capability of the mobile terminal 21. When holding information that can be grasped (for example, maximum transmittable power), the mobile terminal 21 needs to notify the base station controller 25 of the maximum number of E-DCH active sets or Capabilities information. Absent.

When not reporting the maximum number of E-DCH active sets or Capabilities information, there are the following merits.
(1) No additional signaling is added.
(2) The maximum number storage unit 309 of the base station control device 25 is not necessary.
(3) Compared with the case where the maximum number of E-DCH active sets or Capabilities information is notified, compatibility with the conventional technique (R′99) in the base station control device 25 becomes higher.

Hereinafter, the addition (update) process of the E-DCH active set will be described in detail.
The protocol processing unit 130 of the mobile terminal 21 monitors the reception levels of a plurality of neighboring base stations by measuring the reception level of the common pilot channel received by the CPICH reception unit 117, for example, and the reception level is predetermined. When a base station equal to or greater than the threshold value is generated, an E-DCH active set addition event is generated (step ST11).
Further, the protocol processing unit 130 acquires the maximum number of E-DCH active sets stored in the storage unit 129 and outputs the acquired maximum number to the E-DCH active set control unit 126 (step ST12).
However, when Capabilities information is stored in the storage unit 129, the maximum number of E-DCH active sets is set from the Capabilities information, and the maximum number is output to the E-DCH active set control unit 126.

The E-DCH active set addition event needs to be distinguished from the DCH active set addition event on the receiving side. Therefore, it is necessary to newly define an event as an additional event of the E-DCH active set.
Alternatively, an information element for recognizing that the additional event of the E-DCH active set has occurred is added to the additional event of the DCH active set, and the additional event of the DCH active set to which the information element is added is transmitted to the receiving side. To do.
The update event of the E-DCH active set needs to be distinguished from the update event of the DCH active set, similarly to the addition event of the E-DCH active set.

When the protocol processing unit 130 generates an E-DCH active set addition event and receives the maximum number of E-DCH active sets from the protocol processing unit 130, the E-DCH active set control unit 126 of the mobile terminal 21 receives the E-DCH active set control unit 126. The maximum number of DCH active sets is compared with the current number of E-DCH active sets managed by the E-DCH active set management unit 124 (step ST13).
If the current number of E-DCH active sets is less than the maximum number of E-DCH active sets, the E-DCH active set control unit 126 permits an E-DCH active set addition event.
On the other hand, if the current number of E-DCH active sets has already reached the maximum number of E-DCH active sets, or if an E-DCH active set addition event is allowed, the number of E-DCH active sets is If the maximum number of E-DCH active sets is exceeded, an E-DCH active set addition event is rejected and an E-DCH active set update event is generated.

  Here, if the current number of E-DCH active sets has already reached the maximum number of E-DCH active sets, or if an E-DCH active set addition event is allowed, the number of E-DCH active sets Is shown for rejecting an E-DCH active set addition event and generating an E-DCH active set update event if the maximum number of E-DCH active sets is exceeded, An update event of the E-DCH active set may be generated.

That is, when the protocol processing unit 130 of the mobile terminal 21 measures the reception level of the common pilot channel received by the CPICH reception unit 117 and compares the reception level with a predetermined threshold, In addition, a threshold for generating an update event is prepared, and the reception level of the common pilot channel is not only compared with a threshold for generating an additional event, but also compared with a threshold for generating an update event.
Then, an E-DCH active set addition event or an E-DCH active set update event is generated based on the comparison result with the two threshold values.
When an E-DCH active set addition event or an E-DCH active set update event is generated, it may be generated under another condition different from the reception level threshold.

When the E-DCH active set control unit 126 permits the E-DCH active set addition event, the protocol processing unit 130 of the mobile terminal 21 outputs the addition event to the DPCH transmission unit 103 (step ST14), and the E-DCH When the active set control unit 126 generates an update event for the E-DCH active set, the update event is output to the DPCH transmission unit 103 (step ST15).
As a result, in the same manner as when the maximum number of E-DCH active sets and the like are transmitted from the mobile terminal 21 to the base station controller 25, an addition event or update event of the E-DCH active set is transmitted to the base station via the base station. It is transmitted to the station controller 25.
Currently, E-DCH signaling is implemented using DPCH. However, it may be possible to implement E-DCH without using DPCH in the future.
In this case, it is also conceivable that an add event, an update event, and the like are transmitted not by DPCH but by E-DCH or other channels.

When receiving the E-DCH active set addition event or update event transmitted from the mobile terminal 21 (step ST16), the radio resource management unit 303 of the base station controller 25 receives the addition event or update event as an E-DCH active event. The data is output to the set control unit 311.
When the E-DCH active set control unit 311 of the base station control device 25 receives an addition event or update event of the E-DCH active set from the radio resource management unit 303, the additional base included in the addition event or update event Get station specification information.
When the E-DCH active set control unit 311 acquires the designation information of the additional base station, the E-DCH active set control unit 311 sets the maximum number of E-DCH active sets stored in the maximum number storage unit 309 as an upper limit, and the base station indicated by the designation information Is included in the active set of E-DCH.

  In the case where the current configuration of the mobile communication system is as shown in FIG. 5, when the E-DCH active set addition event is received, for example, the maximum number of E-DCH active sets is “3”. If so, the number of current E-DCH active sets is “2” (the serving base station 22 and the non-serving base station 23 are base stations in the E-DCH active set), and one base station is active in the E-DCH. There is room to include in the set. If the DCH active set base station 24 is designated as an additional base station, control is performed to include the DCH active set base station 24 in the E-DCH active set.

  Also, when an E-DCH active set update event is received, for example, if the maximum number of E-DCH active sets is “2”, there is already room to include a new base station in the E-DCH active set. Absent. If the DCH active set base station 24 is designated as an additional base station, the non-serving base station 23 is deleted from the E-DCH active set base station at the same time as including the DCH active set base station 24 in the E-DCH active set. Implement control.

Upon receiving a request to add the DCH active set base station 24 to the E-DCH active set from the E-DCH active set control unit 311, the radio resource management unit 303 of the base station control device 25 adds the E-DCH active set. The request is transmitted to the DCH active set base station 24 (step ST17).
When a request for deleting the non-serving base station 23 from the base station of the E-DCH active set is received simultaneously from the E-DCH active set control unit 311 to add the DCH active set base station 24 to the E-DCH active set. The E-DCH active set update request is transmitted to the DCH active set base station 24 (step ST17).

When the DCH active set base station 24 receives the request for adding or updating the E-DCH active set from the base station controller 25, the DCH active set base station 24 uses the signaling load (E-AGCH transmission, E-RGCH transmission, E-HICH transmission, etc.). The number of signaling signals, number of codes, transmission power, etc.).
When the DCH active set base station 24 measures the signaling load, the DCH active set base station 24 determines whether or not there is a margin in the signaling load (step ST18).
For example, it is determined whether there is a margin by determining whether the number of signaling currently in use has reached a predetermined number.
Further, in addition to the number of signaling currently in use, the hardware processing capacity of the DCH active set base station 24 may be determined.

When the signaling load is not sufficient, the DCH active set base station 24 notifies the base station controller 25 that the addition of the E-DCH active set cannot be performed because the signaling is currently insufficient. (Step ST19), the process ends.
On the other hand, when there is a margin in the signaling load, the base station controller 25 is notified that the E-DCH active set can be added (step ST20).

Upon receiving a notification from the DCH active set base station 24, the E-DCH active set control unit 311 of the base station control device 25 can add or update the E-DCH active set based on the notification content. Is determined (step ST21).
When the transmission control unit 302 of the base station control device 25 determines that the E-DCH active set control unit 311 can add the E-DCH active set, the transmission control unit 302 issues an instruction to add the E-DCH active set to the DCH active set. It transmits to the base station 24 (step ST22).
When the E-DCH active set control unit 311 determines that the E-DCH active set can be updated, the E-DCH active set update instruction (update instruction for addition instruction) is sent to the DCH active set base station. At the same time, an update instruction for E-DCH active set (update instruction for deletion instruction) is transmitted to the non-serving base station 23 (step ST22).
In FIG. 9, the non-serving base station 23 to be deleted from the E-DCH active set is not shown for simplification of the drawing.

When receiving the instruction to add or update the E-DCH active set from the base station controller 25, the DCH active set base station 24 performs an E-DCH active set addition process (step ST23).
When the DCH active set base station 24 performs the E-DCH active set addition process, the DCH active set base station 24 notifies the base station control device 25 of the completion of the addition process (step ST24).
When the non-serving base station 23 receives an update instruction for the E-DCH active set from the base station controller 25, the non-serving base station 23 performs a process for deleting the E-DCH active set.
When the non-serving base station 23 performs the deletion process of the E-DCH active set, the non-serving base station 23 notifies the base station control device 25 of the completion of the deletion process.

  When the transmission control unit 302 of the base station control device 25 receives the completion notification of the addition process from the DCH active set base station 24 added to the E-DCH active set, the transmission control unit 302 adds the E-DCH active set via the base station. An instruction or update instruction is transmitted to the mobile terminal 21 (step ST25).

When the P-CCPCH receiving unit 121 receives an instruction to add or update an E-DCH active set from the base station controller 25, the E-DCH active set control unit 126 of the mobile terminal 21 receives the E-DCH active set control unit 126. Under the instruction, the current active set is updated (step ST26).
When the E-DCH active set management unit 124 performs the E-DCH active set addition process or update process, the protocol processing unit 130 of the mobile terminal 21 notifies the base station controller 25 of the completion of the addition process or update process. (Step ST27).

FIG. 9 shows a sequence in the case where the mobile terminal 21 actively performs the E-DCH active set addition (update) process as described above, but FIG. The sequence in the case of performing addition (update) processing of an E-DCH active set is shown.
Hereinafter, an E-DCH active set addition (updating) process performed by the base station controller 25 will be described.

The protocol processing unit 130 of the mobile terminal 21 notifies the base station control device 25 of the reception level or path loss information of the CPICH receiving unit 117 (step ST31).
When the radio resource management unit 303 of the base station control device 25 receives the reception level or path loss information of the CPICH reception unit 117 transmitted from the mobile terminal 21 (step ST32), the reception level or path loss information is sent to the path loss storage unit 305. Store.

The base stations 22, 23 and 24 being served by the base station control device 25 measure the interference amount and the signaling load, and notify the base station control device 25 of the interference amount and the signaling load (steps ST33 and ST35).
When receiving the interference amount and the signaling load transmitted from the mobile terminal 21 (steps ST34 and ST36), the radio resource management unit 303 of the base station control device 25 stores the interference amount in the interference amount storage unit 304 and performs the signaling. The load is stored in the signaling load storage unit 308.

The radio resource management unit 303 of the base station control device 25 includes the path loss information stored in the path loss storage unit 305, the interference amount stored in the interference amount storage unit 304, and the signaling load stored in the signaling load storage unit 308. To determine whether or not to add a base station to be included in the E-DCH active set (step ST37).
When determining that it is necessary to add a base station to be included in the E-DCH active set, the radio resource management unit 303 generates an E-DCH active set addition event (step ST38).

When the E-DCH active set control unit 311 of the base station controller 25 receives an E-DCH active set addition event from the radio resource management unit 303, the E-DCH active set control unit 311 stores the E-DCH active set stored in the maximum number storage unit 309. The maximum number is confirmed (step ST39).
However, when the maximum number storage unit 309 stores not the maximum number of E-DCH active sets but Capabilities information, the maximum number of E-DCH active sets is set from the Capabilities information.

When the E-DCH active set control unit 311 confirms the maximum number of E-DCH active sets in the mobile terminal 21, the E-DCH active set management unit 310 and the current number managed by the E-DCH active set management unit 310 The number of E-DCH active sets is compared (step ST40).
If the current number of E-DCH active sets is less than the maximum number of E-DCH active sets, the E-DCH active set control unit 311 permits an E-DCH active set addition event.
On the other hand, if the current number of E-DCH active sets has already reached the maximum number of E-DCH active sets, or if an E-DCH active set addition event is allowed, the number of E-DCH active sets is If the maximum number of E-DCH active sets is exceeded, an E-DCH active set addition event is rejected and an E-DCH active set update event is generated.

When the E-DCH active set control unit 311 permits an E-DCH active set addition event, the transmission control unit 302 of the base station control device 25 transmits an E-DCH active set addition instruction to the DCH active set base station 24. (Step ST41).
When the E-DCH active set control unit 311 generates an update event for the E-DCH active set, the E-DCH active set update instruction (update instruction for addition instruction) is transmitted to the DCH active set base station 24 at the same time. Then, an E-DCH active set update instruction (update instruction for deletion instruction) is transmitted to the non-serving base station 23 (step ST42).
In FIG. 10, the non-serving base station 23 to be deleted from the E-DCH active set is not shown for simplification of the drawing.

When receiving the instruction for adding or updating the E-DCH active set from the base station controller 25, the DCH active set base station 24 performs an E-DCH active set addition process (step ST43).
When the DCH active set base station 24 performs the E-DCH active set addition process, the DCH active set base station 24 notifies the base station control device 25 of the completion of the addition process (step ST44).
When the non-serving base station 23 receives an update instruction for the E-DCH active set from the base station controller 25, the non-serving base station 23 performs a process for deleting the E-DCH active set.
When the non-serving base station 23 performs the deletion process of the E-DCH active set, the non-serving base station 23 notifies the base station control device 25 of the completion of the deletion process.

  When the transmission control unit 302 of the base station control device 25 receives the completion notification of the addition process from the DCH active set base station 24 added to the E-DCH active set, the transmission control unit 302 adds the E-DCH active set via the base station. An instruction or an update instruction is transmitted to the mobile terminal 21 (steps ST45 and ST46).

When the P-CCPCH receiving unit 121 receives an instruction to add or update an E-DCH active set from the base station controller 25, the E-DCH active set control unit 126 of the mobile terminal 21 receives the E-DCH active set control unit 126. Under the instruction, the current active set is updated (step ST47).
When the E-DCH active set management unit 124 performs the E-DCH active set addition process or update process, the protocol processing unit 130 of the mobile terminal 21 notifies the base station controller 25 of the completion of the addition process or update process. (Step ST48).

  As is apparent from the above, according to the first embodiment, the maximum number of non-serving base stations selected by the base station control device 25 is prepared in a plurality of ways, and the maximum number of non-serving base stations prepared in a plurality of ways is prepared. Since the maximum number is set according to the capability of the mobile terminal 21 among the numbers, if the mobile terminal 21 is, for example, the mobile terminal B having a low transmission rate, the reception circuit of the mobile terminal 21 There is an effect that the circuit scale can be reduced.

Hereinafter, the effect of this Embodiment 1 is demonstrated concretely.
First, effects in the mobile terminal 21 will be described.
Among the maximum number of non-serving base stations prepared in plural, the maximum number of non-serving base stations applied to the mobile terminal 21 is set according to the capability of the mobile terminal 21 and stored in the storage unit 129. Therefore, for example, when the mobile terminal 21 is a low-performance mobile terminal B (a mobile terminal with a low maximum transmission rate that can be transmitted), hardware for receiving a Down command (for example, the E-RGCH reception unit 119, RAKE There is an effect that it is not necessary to mount the combining unit 206 and the decoding unit 207 on the same scale as the high-performance mobile terminal A (mobile terminal having a high maximum transmission rate that can be transmitted).

The hardware for receiving ACK / NACK information (E-HICH receiving unit 127) indicating whether or not the E-DCH is received from the base stations 22, 23 and 24 is also the same scale as the high-performance mobile terminal A. This eliminates the need for mounting.
That is, if the mobile terminal 21 is a low-performance mobile terminal B, an effect of reducing hardware such as the E-RGCH reception unit 119 and the E-HICH reception unit 127 can be obtained.

Since the high-performance mobile terminal A can transmit at a high rate, the number of non-serving base stations that need to consider the influence on the interference margin is generally higher than that of the low-performance mobile terminal B. To be more.
In this Embodiment 1, since the maximum number of E-DCH active sets is prepared as a mobile communication system, the non-serving base in which the amount of interference in the high-performance mobile terminal A exceeds the allowable amount as before For the station, it is possible to control the transmission power of the data transmitted from the mobile terminal A, and it is possible to solve the problem without deteriorating interference with the non-serving base station due to uplink transmission.

Next, effects of the entire mobile communication system will be described.
In addition to the effect of reducing the hardware of the E-RGCH receiving unit 119 and the E-HICH receiving unit 127 in the mobile terminal 21, code allocation and transmission power reduction in the non-serving base station, non-serving base station The effect of reducing the E-DCH reception processing in the non-serving base station and the traffic of the E-DCH reception data transmitted from the non-serving base station to the base station control device 25 can be obtained.

Embodiment 2. FIG.
In the first embodiment, the maximum number is set according to the capability of the mobile terminal 21 out of the maximum number of non-serving base stations prepared in multiple ways. Now, a method for setting the maximum number will be specifically described.

The 3GPP (3rd Generation Partnership Project) standard already recognizes the presence of a low-performance mobile terminal B that cannot transmit at a high transmission rate as the capability (UE Capabilities) of the mobile terminal.
FIG. 11 is an explanatory view showing the capability (UE Capabilities) of the mobile terminal related to E-DCH standardized by the 3GPP standard. In the figure, TTI is an abbreviation for “Transmission Timing Interval”.
FIG. 12 is an explanatory diagram showing an example of correspondence between Capabilities information and the maximum number of E-DCH active sets.

As described in the first embodiment, generally, the mobile terminal A with high capability increases the maximum number of E-DCH active sets, and the mobile terminal B with low capability increases the maximum number of E-DCH active sets. It is desirable to make it smaller.
Although the specific numerical range of the maximum number of E-DCH active sets is not particularly limited, it is generally considered that the maximum number of E-DCH active sets ranges from 6 or less. -When the maximum number of DCH active sets is small, it is considered to be about 3-4, and when it is large, about 5-6.

(1) As a direct notification method, the mobile terminal 21 may hold the maximum number of E-DCH active sets and notify the base station controller 25 of the maximum number.
As a specific notification method, the base station controller 25 is notified by sending a layer 3 message by a protocol called RRC (Radio Resource Control).
Since it can be specified independently of the conventional UE Capabilities definition, there is an advantage that the degree of freedom of setting is high.

(2) As an indirect notification method associated with UE Capabilities related to E-DCH, it is conceivable that the mobile terminal 21 holds Capabilities information and notifies the Capabilities information to the base station controller 25.
Specific examples of the method of associating the maximum number of E-DCH active sets and UE capabilities are shown below. In this case, however, the base station controller 25 only needs to signal the category number, Since the maximum number of actual E-DCH active sets can be derived, there is an advantage that the amount of signaling can be reduced.

As a first example, the maximum number of E-DCH active sets may be set using “category” of Capabilities information as a key.
A category means classification. Generally, the larger the number of categories, the higher the capability of the mobile terminal 21.
Therefore, a larger maximum number is assigned to a mobile terminal having a larger number of categories (see FIG. 12 (1)).

  In FIG. 12 (1), Category 1 is “1”, Category 2 is “1”, Category 3 is “2”, Category 4 is “3”, and Category 5 is “4”. For the category, the maximum number of E-DCH active sets is assigned to a category having a high maximum transmission rate, and the maximum number of E-DCH active sets is assigned to a category having a low maximum transmission rate. Try to allocate less.

As a second example, the maximum number of physical channels that can be transmitted (maximum number of E-DCH codes: Maximum number of E-DCH codes transmitted) is used as a key to set the maximum number of E-DCH active sets. Can be considered.
The code means a channelization code that is a spreading code for channel separation.
Using multiple channelization codes to transmit E-DCH means that multiple physical channels are used for E-DCH at the same time, and this state is called multicode.
FIG. 13 is a detailed configuration diagram showing the modulation unit 112 of the mobile terminal 21 at the time of multi-coding. FIG. 13 illustrates a case where the category of FIG. 11 is “6”.
In general, a mobile terminal having a larger number of multi-codes (physical channels to be transmitted simultaneously) is said to be a high-performance mobile terminal in E-DCH transmission.
Therefore, a larger maximum number is assigned to a mobile terminal having a larger maximum number of physical channel transmissions (see FIG. 12 (2)).

  Note that the number of allocations shown in FIG. 12 (2) is merely an example, and for the maximum number of physical channels to be transmitted, a larger maximum number of E-DCH active sets is allocated to a large hardware scale, Conversely, a small number of E-DCH active sets are allocated to a small hardware scale.

As a third example, the maximum number of E-DCH active sets may be set using a minimum spreading factor (MSF) that can be transmitted as a key.
The diffusion coefficient SF is a coefficient indicating to which chip 1 symbol is diffused.
The number of chips that can be transmitted per second depends on the chip rate and is a fixed value. The chip rate in the current W-CDMA system is 3.84 MHz. That is, the number of chips that can be transmitted per second is 3.84 Mchip / s.
A mobile terminal with a smaller spreading factor SF increases the number of symbols that can be transmitted per second.
Further, as the spreading coefficient SF is smaller, gain cannot be obtained and transmission power is required.
From this, it can be said that a mobile terminal that supports a small spreading factor SF is a high-performance mobile terminal in E-DCH transmission.
Therefore, a larger maximum number is assigned to a mobile terminal that can transmit with a small spreading factor SF (see FIG. 12 (3)).

  Note that the number of allocations shown in FIG. 12 (3) is merely an example, and for the minimum transmission coefficient that can be transmitted, a large maximum number of E-DCH active sets are allocated to those having a high maximum transmission rate, and vice versa. In addition, a small maximum number of E-DCH active sets is allocated to a low maximum transmission rate. In addition, a large number of E-DCH active sets are allocated to a large hardware scale, and a small maximum number of E-DCH active sets is allocated to a small hardware scale. To do.

As a fourth example, the maximum number of E-DCH active sets can be set using the ETICH TTI length as a key.
TTI is an abbreviation for “Transmission Timing Interval”.
First, consider the TTI length of E-DCH. In the 3GPP R'99 standard (standard before E-DCH is standardized), 2 ms TTI is not supported. That is, it can be said that it is a high-performance mobile terminal that there is a margin that can support 2 ms TTI (for example, a margin in hardware implementation in the mobile terminal) at the E-DCH function addition stage.
Although 10 ms TTI can be transmitted by all mobile terminals, 2 ms TTI is supported only for highly functional mobile terminals.
Therefore, if 2 ms TTI is supported, it is regarded as a high function mobile terminal, and the maximum number of E-DCH active sets is increased. If 2 ms TTI is not supported, it is regarded as a low function mobile terminal, and E-DCH The maximum number of DCH active sets is reduced (see FIG. 12 (4)).
In DCH (3GPP R'99 standard), the idea of the TTI length and the capability of the mobile terminal is opposite to the above case, and the longer the TTI length, the more memory is required to be received. It is considered a functional mobile terminal.
Another way of thinking. Assuming that the mobile terminal transmits the same amount of data, it can be said that the peak rate is higher when the TTI length is 2 ms than when the TTI length is 10 ms. Therefore, if 2 ms TTI is supported, it is regarded as a high performance mobile terminal, and the maximum number of E-DCH active sets is increased. If 2 ms TTI is not supported, it is regarded as a low performance mobile terminal, and E-DCH The maximum number of DCH active sets is reduced (see FIG. 12 (4)). The number of allocations shown in FIG. 12 (4) is merely an example, and for the TTI length of E-DCH, a large maximum number of E-DCH active sets is allocated to ones with a high maximum transmission rate. A small maximum number of E-DCH active sets is allocated to a low maximum transmission rate.

  The number of allocations shown in FIG. 12 (4) is merely an example. For the TTI length of E-DCH, a large number of E-DCH active sets are allocated to a large hardware scale, and conversely A small number of E-DCH active sets are allocated to a small hardware scale.

As a fifth example, the maximum number of E-DCH active sets may be set using the transport block size (size of data unit to be transmitted) as a key.
The fact that the maximum transport block size is large indicates that the processing capability is high, so that it is regarded as a highly functional mobile terminal and a large maximum number is assigned (see FIG. 12 (5)).

  Note that the number of allocations shown in FIG. 12 (5) is merely an example, and for the transport block size, a large maximum number of E-DCH active sets are allocated to those having a high maximum transmission rate, and conversely, A small maximum number of E-DCH active sets is allocated to a low maximum transmission rate. In addition, a large number of E-DCH active sets are allocated to a large hardware scale, and a small maximum number of E-DCH active sets is allocated to a small hardware scale. To do.

The first to fifth examples are merely examples, and the maximum number of E-DCH active sets may be set in correspondence with other E-DCH Capabilities information.
In addition, the maximum number of E-DCH active sets specified in the first to fifth examples is an example value and may actually be different.

FIG. 14 is an explanatory diagram showing a Capabilities assumption table regarding E-DCH when the mobile communication system prepares a plurality of maximum E-DCH active sets.
In the example of FIG. 14, the same value as the value of FIG. 12 (3) is inserted in the column of the maximum number of E-DCH active sets at the right end, but (1) (2) (4) of FIG. The value of (5) and other values may be inserted.

(3) As an implicit notification method associated with UE Capabilities related to 3GPP R'99, there is a method in which the number is determined in advance without special signaling.
By looking at other information from which it can be determined that the mobile terminal has a high capability, the maximum number of E-DCH active sets is uniquely set based on the information.
As a guideline indicating that the capability is high, “UE Power Class” indicating the maximum transmittable power of the mobile terminal, the maximum TTI length that can be received, and the like are conceivable. When “UE Power Class” is large, the maximum transmission power is large. Therefore, if “UE Power Class” is large, it is regarded as a high-performance mobile terminal, the maximum number of E-DCH active sets is increased, and if “UE Power Class” is small, it is regarded as a low-performance mobile terminal. The maximum number of DCH active sets is reduced. Further, when the maximum receivable TTI length is large, the memory required for reception increases. Therefore, if the receivable maximum TTI length is large, it is regarded as a high-performance mobile terminal, the maximum number of E-DCH active sets is increased, and if the receivable maximum TTI length is small, it is regarded as a low-performance mobile terminal, The maximum number of E-DCH active sets is reduced. The signaling function may remain the same as before, and there is an advantage that compatibility is improved because there is no new additional signaling.

Embodiment 3 FIG.
In the third embodiment, modified examples 1 and 2 of the first embodiment will be described.
As a first modification, the following situation is assumed.
That is, it is assumed that the non-serving base station 23 lacks the number of assigned downlink codes, transmission power, etc., and wants to save the downlink channels to be transmitted.
In addition, since the transmission path changes drastically and the E-DCH reception error occurs more frequently in the serving base station 22, a request to increase the effect of macro diversity is generated as a mobile communication system. .
In addition, it is assumed that the non-serving base station 23 has an interference margin and does not need to transmit a Down command to the mobile terminal 21.

Under the above situation, some non-serving base stations 23 included in the E-DCH active set receive E-DCH data transmitted from the mobile terminal 21, but do not transmit a Down command. A mobile communication system can be considered.
In this case, the hardware of the E-RGCH receiving unit 119 in the mobile terminal 21 can be reduced.
Further, as a whole mobile communication system, it is possible to reduce code allocation, transmission power, and the like of the non-serving base station 23.

Next, as Modification 2, the following situation is assumed.
That is, it is assumed that the non-serving base station 23 lacks the number of assigned downlink codes, transmission power, etc., and wants to save the downlink channels to be transmitted.
Furthermore, since the transmission path is stable, the frequency of occurrence of E-DCH reception errors in the serving base station 22 is low, and it is assumed that the macro diversity effect is not necessary as a mobile communication system.
However, the non-serving base station 23 has a large number of terminals that need to consider the amount of interference, or the non-serving base station 23 has a high transmission rate of mobile terminals that need to consider the amount of interference. It is assumed that the station 23 has no interference margin and needs to transmit a Down command to the mobile terminal 21.

Under the above situation, some non-serving base stations 23 included in the E-DCH active set do not receive E-DCH data transmitted from the mobile terminal 21, but transmit a Down command. A mobile communication system can be considered.
In this case, in the mobile terminal 21, the hardware of the E-HICH receiving unit 127 in the mobile terminal 21 can be reduced.
Also, as a whole mobile communication system, code allocation and transmission power of the non-serving base station 23 are reduced, E-DCH reception processing in the non-serving base station 23 is reduced, and the non-serving base station 23 to the base station controller The effect of reducing the traffic of E-DCH reception data transmitted to 25 is obtained.

  As described above, the mobile communication system according to the present invention is suitable for a high necessity of reducing the hardware scale of a mobile terminal such as a mobile phone.

  1,21 mobile terminal, 2a, 2b, 24 DCH active set base station, 3,25 base station controller, 11, 22 serving base station, 12-1, 12-2, 12-3, 23 non-serving base station, 101, 301 control unit, 102 transmission buffer, 103 DPCH transmission unit, 104 power management unit, 105 transmission rate control unit, 106 HARQ processing unit, 107 scheduling request information creation unit, 108 encoder unit, 109 E-DCH transmission unit, 110 Retransmission control unit, 111 E-DPCCH transmission unit, 112 modulation unit, 113 power amplification unit, 114 antenna, 115 low noise amplification unit, 116 demodulation unit, 117 CPICH reception unit, 118 E-AGCH reception unit, 119 E-RGCH reception , 119-1 to 119-3 E-RGCH receiving circuit, 12 DPCH receiver, 121 P-CCPCH receiver, 122,306 DCH active set manager, 123,307 DCH active set controller, 124,310 E-DCH active set manager, 125 correlation calculator, 126, 311 E- DCH active set control unit, 127 E-HICH reception unit, 128 SG management unit, 129 storage unit, 130 protocol processing unit, 201 frequency conversion unit, 202 A / D conversion unit, 203-1, 203-2, 203-3 Search unit, 204-1, 204-2, 204-3 code generator, 205-1, 205-2, 205-3 finger assignment control unit, 206a-1 to 206d-1, 206a-2 to 206d-2, 206a-3 to 206d-3 finger portions, 206, 206-1, 206-2 206-3 RAKE combining unit, 206e-1 to 206e-3 cell combining unit, 207-1 to 207-3 decoding unit, 302 transmission control unit, 303 radio resource management unit, 304 interference amount storage unit, 305 path loss storage unit, 308 Signaling load storage unit, 309 Maximum number storage unit.

Claims (13)

  A plurality of base stations that receive macro diversity data transmitted from a mobile terminal, and a base that selects a non-serving base station having a control function for controlling transmission power of data in the mobile terminal from the plurality of base stations In a mobile communication system comprising a station controller, the maximum number of non-serving base stations selected by the base station controller is set according to the capability information received from the mobile terminal. Mobile communication system.   A plurality of base stations that receive macro diversity data transmitted from a mobile terminal, and a base that selects a non-serving base station having a control function for controlling transmission power of data in the mobile terminal from the plurality of base stations In a mobile communication system comprising a station controller, a plurality of maximum numbers of non-serving base stations selected by the base station controller are prepared in accordance with capability information received from the mobile terminal. A mobile communication system.   3. The mobile communication system according to claim 2, wherein a maximum number is set according to capability information received from a mobile terminal from among a maximum number of non-serving base stations prepared in a plurality of ways.   The mobile unit according to claim 3, wherein the maximum number of non-serving base stations is set in advance according to the capability of the mobile terminal, and the mobile terminal notifies the base station controller of the preset maximum number. Communications system.   4. The mobile communication system according to claim 3, wherein the base station controller grasps the capability of the mobile terminal and sets the maximum number of non-serving base stations according to the capability of the mobile terminal.   6. The mobile communication according to claim 5, wherein the mobile terminal notifies the base station controller of capability information indicating its own capability, and the base station controller recognizes the capability of the mobile terminal from the capability information. system.   Maximum number acquisition means for acquiring the maximum number of non-serving base stations from the mobile terminal when the maximum number of non-serving base stations having a control function for controlling the transmission power of data in the mobile terminal is set in the mobile terminal And non-serving base station selection that selects a non-serving base station from a plurality of base stations that receive macro diversity data transmitted from the mobile terminal, with the maximum number acquired by the maximum number acquisition means as an upper limit. And a base station control device.   When there are a plurality of non-serving base stations having a capability grasping means for grasping the capability of the mobile terminal and a control function for controlling the transmission power of data in the mobile terminal, the maximum number of the non-serving base stations The maximum number setting means for setting the maximum number of non-serving base stations according to the ability grasped by the ability grasping means, and the maximum number set by the maximum number setting means as the upper limit, the movement A base station control apparatus comprising: a non-serving base station selecting unit that selects a non-serving base station from a plurality of base stations that receive macro diversity data transmitted from a terminal.   9. The base station controller according to claim 8, wherein the capability grasping means collects capability information indicating its own capability from the mobile terminal, and grasps the capability of the mobile terminal from the capability information.   When the maximum number of non-serving base stations having a control function for controlling the transmission power of data is set in advance according to its own capability, maximum number storage means for storing the maximum number of the non-serving base stations, and Maximum number notification means for notifying the base station controller of the maximum number of non-serving base stations stored in the maximum number storage means, and reception for the maximum number of non-serving base stations stored in the maximum number storage means And a power adjustment unit that adjusts the power of transmission data according to the control signal when the reception circuit receives the transmission power control signal from the non-serving base station selected by the base station controller. Mobile terminal.   If the current number of non-serving base stations is smaller than the maximum number of non-serving base stations stored in the maximum number storage means, a request to add a non-serving base station is transmitted to the base station controller, and the current non-serving base station When the number of stations is equal to or greater than the maximum number of non-serving base stations stored in the maximum number storage means, an additional update request means is provided for transmitting a non-serving base station update request to the base station controller. The mobile terminal according to claim 10.   A maximum number storage means for storing the maximum number of non-serving base stations when the maximum number of non-serving base stations having a control function for controlling transmission power of data is set in advance according to its own capacity; Capacity notification means for notifying the base station controller of capability information indicating the capability of the base station, and receiving circuits for the maximum number of non-serving base stations stored in the maximum number storage means, the receiving circuits being the base station A mobile terminal comprising: a power adjustment unit that adjusts the power of transmission data according to a control signal when a transmission power control signal is received from a non-serving base station selected by the station control device.   If the current number of non-serving base stations is smaller than the maximum number of non-serving base stations stored in the maximum number storage means, a request to add a non-serving base station is transmitted to the base station controller, and the current non-serving base station When the number of stations is equal to or greater than the maximum number of non-serving base stations stored in the maximum number storage means, an additional update request means is provided for transmitting a non-serving base station update request to the base station controller. The mobile terminal according to claim 12.

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