JP2003304189A - Radio base station device and communication terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid call disconnection in advance in performing site selection diversity transmission control. <P>SOLUTION: N pieces of past ID label information received from a communication terminal are stored in a storing part 109b. If even one ID label showing that it is a primary cell is included in the N past ID labels, a primary cell determining part 109 determines that the self-station is a primary cell. A transmitting power control part 112 performs transmission control so as to transmit a DPDCH (dedicated physical data channel) to a communication terminal when the primary cell determining part 109 determines that the self-station is a primary cell. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

The present invention relates to a CDMA (Code D
The present invention relates to a wireless base station device and a communication terminal device used for ivision multiple access) communication.

[0002]

2. Description of the Related Art In recent years, the demand for land mobile communications such as automobiles and mobile phones has increased remarkably, and in addition to high speed and high quality transmission, in order to secure more subscriber capacity in a limited frequency. Effective frequency utilization technology has become important.

The CDMA system has been attracting attention as one of multiple connections for effective use of frequencies. The CDMA system is a multiple access system that uses spread spectrum communication technology, is not easily affected by multipath distortion, and has the characteristics that a diversity effect can be expected by performing RAKE reception.

Rake reception will be briefly described. In mobile communication, a transmission wave from a transmission station directly arrives at the reception station, and a reflected wave arrives at the reception station after being reflected by a building or the like. Will be combined and received. In this case, since there are many paths of reflected waves, the reflected waves of many paths (multipath) are received. Therefore, the reception station receives the composite wave of the reception signals passing through many paths, but these reception signals include the propagation delay time due to each path.
As a result, in the receiving station, the received signals interfere with each other to cause fading.

The spread code of the CDMA system has a small autocorrelation when it is offset in time. Utilizing this, in the despreading unit, when despreading is performed with a spreading code given a phase offset corresponding to the propagation delay time,
It is possible to obtain the received signal having the propagation delay time corresponding to the phase offset.

That is, by giving a phase offset corresponding to the propagation delay time to the phase of the spread code, it is possible to obtain each of the received signals without causing interference with each other. Therefore, a plurality of despreading units are provided in parallel, and despreading processing is performed in each despreading unit by using a despreading code with a phase offset corresponding to the propagation delay time of the received signal. It is possible to independently obtain the received signals of.

A good demodulated signal can be obtained by adding a predetermined weight to the plurality of received signals obtained in this way and adding and combining them. The method of receiving in this way is called RAKE reception, and since the received signals from a plurality of paths can be selectively despread and combined, path diversity reception can be performed.

On the other hand, at present, 3GPP (3rd Generation Par
tnership Project) C is being standardized
In the DMA communication system, the common pilot channel (C
There is a channel called PICH (Common Pilot CHannel). This is a channel that is always transmitting pilot symbols, and by using this channel, the mobile station can perform channel estimation even for communication channels that do not contain pilot symbols and perform synchronous detection. Become.

SSDT (Site) is one of the transmission power control methods.
Selection Diversity Transmit power control). In SSDT, as shown in FIG. 10, the mobile station MS transmits the first common pilot channel (P-CP) from each cell Cell # 0 to Cell # 2 (that is, each base station BTS).
The reception level of ICH (Primary CPICH) is measured, and the cell with the highest reception level is determined as the primary cell. Then, the ID label indicating the primary cell is included in FBI (FeedBack Information) and transmitted to the base station.

The base station determines whether or not the own station is a primary cell based on the FBI ID label,
Only the base station that is the immediate cell has DPCCH (D
dedicated Physical Control Channel) and DPDCH
(Dedicated Physical Data Channel) is transmitted. On the other hand, cells other than the primary cell (Non Pr
The base station of the image cell) transmits only the DPCCH. By this means, it is possible to limit the base stations that perform downlink transmission, so that it is possible to reduce the amount of interference of downlink signals.

[0011]

However, the SSD
Performing T may result in call disconnection in some circumstances. For example, when a mobile station enters the shadow of a building. In this case, if SSDT is not performed,
Communication can be continued by receiving the transmission wave from the base station of another cell. However, if SSDT is performed, Primar
Since only the y cell base station is transmitting the DPDCH, if the signal becomes unreceivable, it immediately becomes unreceivable.

The present invention has been made in view of the above points, and an object of the present invention is to provide a radio base station apparatus and a communication terminal apparatus capable of avoiding call disconnection even when site selection diversity transmission control is performed. To do.

[0013]

In order to solve such a problem, the present invention has the following constitution.

(1) The radio base station apparatus of the present invention performs site selection diversity transmission control,
A wireless base station device used in a wireless communication system configured to transmit a DPDCH signal only from a base station determined to be a primary cell, and storage means for storing past N ID label information received from a communication terminal. , And even one of the N ID labels is Primary
When the ID label indicating that the cell is a cell is included, the determining unit that determines that the own station is the Primary cell, and the determining unit determines that the own station is the Primary cell
When it is determined to be a cell, the DPD is applied to the communication terminal.
And a transmission means for transmitting a CH signal.

According to this structure, even when the site selection diversity transmission control is performed, a plurality of base stations can be connected to the Pris.
It becomes possible to behave as a Mary cell, and as a result, it becomes possible to reduce the probability of call disconnection.

(2) The communication terminal device of the present invention performs P
D from only base stations determined to be primary cells
A communication terminal device used in a wireless communication system adapted to transmit a PDCH signal, comprising: reception quality measuring means for measuring reception quality of signals from a plurality of base stations; The base station of
determination means for determining as a cell, and an ID indicating that it is a primary cell for the top N base stations
And a transmitting means for transmitting label information.

According to this structure, even when the site selection diversity transmission control is performed, a plurality of base stations are connected to the Pri stations.
It becomes possible to behave as a Mary cell, and as a result, it becomes possible to reduce the probability of call disconnection.

(3) In the communication terminal device according to the present invention, the determining means of (2) has the addition of the reception quality of the signal from each base station,
In consideration of the number of reception paths of signals from each base station,
The rycell is determined and the configuration is adopted.

According to this configuration, when the difference in reception quality when determining the upper N base stations is less than or equal to a predetermined threshold value, cells having a large number of reception paths are given priority to the primary cell.
If it is set to 1, it becomes possible to stabilize the reception.

(4) In the communication terminal device according to the present invention, the determining means of (2) determines the upper N base stations that have been determined to be Primary cells at a certain time, and determines the upper N base stations of the upper N base stations at a later time. If there is a base station with a better reception quality than the reception quality, and if the difference between the reception quality and the reception qualities of the top N base stations selected previously is less than or equal to a predetermined threshold value, P
The configuration is adopted without changing the primary cell.

According to this configuration, the upper N base stations which are the actual communication targets are not unnecessarily changed frequently, so that the closed loop power control during transmission diversity can be stabilized.

(5) In the communication terminal device according to the present invention, the determining means of (2) determines, according to the magnitude of the difference in the reception quality from each base station, the moving speed of the own station or the variation in the reception quality. Prim
Change the number of base stations that are determined to be an ary cell,
Take the composition.

According to this configuration, for example, when a small number of cells whose reception quality is excellent and a few cells are detected, the Primary is detected.
If you reduce the number of cells, unnecessary Primary
Since it is not necessary to increase the number of cells, the interference component can be reduced.
If the moving speed of the communication terminal device is fast,
By increasing the number of y cell cells, it is possible to stabilize the reception quality during movement and reduce interference waves at the time of stop. When the amount of fluctuation in reception quality is small, even if the number of primary cells is reduced,
Since the probability of call disconnection does not increase so much, the interference component can be effectively reduced.

(6) In addition to the configuration of (2), the communication terminal device of the present invention is further provided with a determining means for primary communication.
Transmission power for generating a transmission power control signal to the upper N base stations so that the SIR when the signals from the upper N base stations determined to be cell are combined is obtained and the SIR value approaches the target value. A configuration including a control signal generating means is adopted.

With this configuration, the probability of call disconnection can be further reduced, and unnecessary interference components can be suppressed.

(7) In addition to the configuration of (2), the communication terminal device of the present invention further comprises a determining means for primary communication.
Phase difference measuring means for measuring the inter-antenna phase difference of each base station signal based on the received signals from the upper N base stations determined to be cell, and the inter-antenna phase difference is small for the upper N base stations. And a phase control signal generating means for generating the phase control signal.

According to this configuration, the primary ce
Since it is possible to improve the reception quality of the base station signal determined to be ll, it is possible to further reduce the probability of call disconnection.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The essence of the present invention is that the past N (N is an integer of 1 or more) IDs received from a communication terminal by a base station when performing site selection diversity transmission control.
Refer to the label and at least one of the N Primaries
When an ID label indicating cell exists, Pri
This means that it operates as a Mary cell (transmits DPDCH in addition to DPCCH).

Further, the mobile station determines the upper N base stations having good reception quality as primary cells, and determines the upper N base stations.
That is, the ID label information indicating that the cell is a primary cell is transmitted to each of the base stations.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1) FIG.1 is a block diagram showing the configuration of radio base station apparatus 100 according to Embodiment 1 of the present invention. The wireless base station device 100 includes an antenna 101.
The received signal received in step 3 is input to the RF unit 102. The RF unit 102 performs wireless processing such as amplification of received signals and transmitted signals and frequency conversion. The reception signal that has been subjected to the wireless reception processing by the RF unit 102 is an analog-digital conversion circuit
D) is input to a plurality of despreading units 104 via 103. Each despreading unit 104 uses the same spreading code as the spreading code used in the spreading process of the terminal station of the communication partner, and despreads the received signal at a slightly shifted timing. Incidentally, in FIG. 1, only the reception system and the transmission system for one communication terminal are shown for simplification of the drawing, but the radio base station device 100 is actually a reception system and a transmission system for a plurality of communication terminals. Have.

Phase estimating section 105 finds a phase estimated value of the signal after despreading based on the pilot signal, and sends this to synchronous detecting section 106. The synchronous detection unit 106 calculates the complex conjugate of the phase estimation value from the phase estimation unit 105, and multiplies the complex conjugate by the despread signal to perform phase compensation and RAK.
E weighting processing is performed. The RAKE combining unit 107 assigns each synchronous detection output to a finger and combines a plurality of synchronous detection outputs. Decoding section 108 performs error correction decoding processing on the RAKE-combined signal.

Encoding section 110 performs error correction encoding processing on the downlink transmission signal, and transmits the processed signal from antenna 101 via digital-analog conversion circuit (D / A) 111 and RF section 102.

Primary cell determination section 109
Is the primary cell from the received FBI.
It is determined whether it is l. By the way, FBI (FeedBack Inf
is a pilot symbol or TFCI (Transport Format Combination Indicato) by the DPCCH.
r), information transmitted together with TPC (Transmit Power Control) bits. For FBI, your station is Primar
In addition to the ID label information indicating whether the cell is y cell, information for controlling the phase difference between the antennas when performing transmission diversity is included.

Here, the primary cell determination unit 1
09 extracts the ID label from the upstream FBI and transfers it to the storage unit 109b. The storage unit 109b is configured to store the past N ID labels. Prima
The ry cell determination unit 109 checks the ID label stored in the storage unit 109b, and even one of the ID labels is printed by the Primer.
If there is an ID label indicating ry cell, the own station is Pri
It is determined to be a Mary cell.

The transmission power control unit 112 uses the Primary
The determination result of the cell determination unit 109 is Primary c
If it indicates that the cell is a cell, the RF unit 102 is controlled so that the DPDCH is transmitted in addition to the DPCCH, and if the cell is not a primary cell, only the DPCCH is transmitted.

According to the above configuration, when the past N number of ID labels received from a certain communication terminal are referred to and at least one of the N number of ID labels indicates that the own station is a primary cell, , DP for the communication terminal
By transmitting the DPDCH in addition to the CCH, it becomes possible for a plurality of base stations to behave as a primary cell even during site selection diversity transmission control, and as a result, the probability of call disconnection can be lowered. The wireless base station device 100 capable of being realized can be realized.

(Embodiment 2) In this embodiment, based on the reception qualities of signals received by a communication terminal from a plurality of base stations, the primary cell for the top N base stations in descending order of reception quality is selected. The ID label indicating that is created is transmitted to the base station. That is, in the first embodiment, the communication terminal has the same configuration as the conventional one, and the past N pieces (N is 1) received from the communication terminal by the base station.
The above (integer) ID label is referred to, and when at least one of the N ID labels indicates a Primary cell, it operates as a Primary cell (also transmits the DPDCH in addition to the DPDCH). In the second embodiment, the upper N base stations with good reception quality are set in advance by the communication terminal in accordance with the primary cell.
It is designed to be designated as l.

FIG. 2 is a block diagram showing the configuration of communication terminal apparatus 200 according to Embodiment 2 of the present invention. Communication terminal apparatus 200 inputs the reception signal received by antenna 201 to RF section 202. The RF unit 202 performs wireless processing such as amplification of received signals and transmitted signals and frequency conversion. RF
The reception signal subjected to the wireless reception processing by the unit 202 is input to the plurality of despreading units 204a and 204b via the analog-digital conversion circuit (A / D) 203.

Here, in communication terminal apparatus 200, P-CPICH reception signals from a plurality of base stations are despread by a plurality of despreading sections 204a, and DPCH reception signals from a plurality of base stations are despread. Despreading is performed by the spreading unit 204b. Specifically, each despreading unit 204a uses the spreading code corresponding to the spreading code of each base station to set P
-By despreading the CPICH, the pilot signal included in the P-CPICH from each base station is reproduced. Similarly, each despreading unit 204b uses the spreading code corresponding to the spreading code of each base station to perform DP.
By despreading the CH, the transmission data contained in the DPCH from each base station is reproduced.

The phase estimation unit 205 obtains a phase estimation value of the signal after despreading based on the pilot signal, and uses this for the synchronous detection unit 206 and RSCP (Received Signal Code Powe).
r) Send to the measuring unit 209. The synchronous detection unit 206 calculates the complex conjugate of the phase estimation value from the phase estimation unit 205, and multiplies the complex conjugate by the despread signal to perform phase compensation and RAKE weighting processing. The RAKE combining section 207 assigns the signal after the synchronous detection to the fingers to combine the synchronous detection outputs. Decoding section 208 performs error correction decoding processing on the RAKE-combined signal.

The RSCP measuring section 209 is provided for each despreading section 20.
The reception level (reception power) of the pilot signal from each base station (cell) obtained by 4a is measured. Specifically, the square of the CPICH phase estimation value output by each phase estimation unit 205 is calculated, and this is added for each cell to obtain the reception level for each cell. Note that, in FIG. 2, the RSCP measuring section is shown as inputting the output of each phase estimating section 205, but the output of each despreading section 204a is directly input to measure the reception level of the pilot signal from each base station. It may be done.

Primary cell determination unit 210
Is based on the reception level of the pilot signal for each cell,
Primarily the top N stations from the one with the highest reception level
Judge as cell. And the ID according to this judgment result
A label is created and sent to the encoding unit 211. By the way,
The ID label is updated in a predetermined cycle. See also Primar
The y cell determination unit 210 determines the cell with the highest reception level as the primary cell, and sends the determination result to the RAKE combining unit 207 via the delay unit 213.

The coding unit 211 performs error correction coding processing on the downlink transmission signal, and at the same time, from the ID label to the FBI.
And add this to the transmitted signal. The encoded signal is a digital-analog conversion circuit (D / A) 212 and R.
It is transmitted from the antenna 201 via the F section 202.

The RAKE combiner 207 includes a Primar
Primar obtained by the y cell determination unit 210
The y cell information is input via the delay unit 213 after being delayed by the transmission path delay and the control delay of the base station. RA
The KE synthesizing unit 207 RAKE-synthesizes only the coherent detection output that is the primary cell, based on the primary cell information.

However, in the communication terminal device 200, as described above, the primary N station with a high reception level is assigned to the upper N station.
Since ry cell information is being sent, P is available for up to N stations.
Since it can be a primary cell, the past N I
A base station that has been determined to be a primary cell by at least one of the D labels is to be combined.

According to the above configuration, the communication terminal device 200
, I indicating that it is a primary cell for the top N base stations in descending order of reception level.
By creating and transmitting the D label, it becomes possible for a plurality of base stations to behave as primary cells even during site selection diversity transmission control, and as a result, the probability of call disconnection can be reduced. The communication terminal device 200 capable of being realized can be realized.

In this embodiment, the case has been described where the upper N station (cell) having a high reception level is determined as the primary cell. However, the primary cell is
The following method may be applied as the determination method of.

For example, when the level difference of the P-CPICH reception power of each cell is less than a certain threshold value, the cell having many reception paths of each cell is preferentially set as the primary cell. This makes it possible to stabilize reception.

In the above embodiment, the case where the ID label is updated at a predetermined cycle has been described. However, regarding the upper N base stations that are determined to be primary cells at a certain point, the upper N number of the upper N base stations is determined at a later point. If there is a base station with better reception quality than the reception quality of the base station, and if the difference between the reception quality and the reception qualities of the top N base stations selected previously is less than or equal to a predetermined threshold, the primary cell
Do not change. As a result, the upper N base stations that are the actual communication targets are not unnecessarily frequently changed, and the closed-loop power control during transmission diversity can be stabilized.

Further, in the above-described embodiment, the upper N base stations from the one having the highest reception level are designated as the primary cemeteries.
The case where it is judged as ll has been described.
The number of cells may be changed according to the difference in reception level of each cell. For example, when a small number of cells having a strong reception level are detected, it is better to reduce the number of primary cells. On the contrary, when there are many cells with similar reception levels, it is better to increase the number of primary cells. When the communication terminal device 200 is moving, the number of primary cell cells is increased, and when the communication terminal device 200 is stopped, the reception quality can be stabilized while moving by reducing the number of primary cells, and at the time of stop. Interference waves can be reduced. Also, when there is little variation in reception quality, the Primary c
Even if the number of cells is reduced, the probability of call disconnection does not increase so much, so that the interference component can be effectively reduced. Furthermore P
When the number of primary cells is less than N, the reliability of ID label transmission can be improved by increasing the number of times of transmitting the ID label of a cell having a strong reception strength.

Further, as shown in FIG. 3 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, the AFC (Automatic Frequency Control) of each cell is based on the output of each phase estimation section 205.
l) An AFC error measuring unit 301 that measures an error may be provided. This communication terminal device 300 is
P-CPICH of each base station obtained by the measurement unit 209
If the reception level difference is less than or equal to a threshold value, the AFC error measurement unit 301 measures the AFC error amount of each cell and Pr
The image cell determining unit 302 preferentially determines a cell with a small error as a primary cell. In this way, the base station with less frequency error is preferentially P
Since it can be a primary cell, demodulation performance can be improved.

Further, as shown in FIG. 4 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, S-CPICH from each base station
A plurality of despreading units 401 that despread (Secondary-Common Pilot Channel) are provided, and each despreading unit 401
A second RSCP measuring section 402 that measures the reception level of the S-CPICH based on the output of the above may be provided. This communication terminal apparatus 400, when the P-CPICH reception level difference of each base station obtained by the first RSCP measurement unit 209 is equal to or less than a threshold value, the communication terminal apparatus 400 measures each cell measured by the second RSCP measurement unit 402. Referring to the reception level of the S-CPICH, the primary cell determination unit 403 preferentially sets the cell having the large reception level of the S-CPICH to P
It is determined as a primary cell. By doing so, the demodulation performance can be improved.

As shown in FIG. 5 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, DPCCH (Dedicated Physical Control) of each cell obtained by each coherent detection section 206.
A second RSCP measuring unit 501 that measures the RSCP of the (Channel) may be provided. This communication terminal device 5
00 is the DPCCH reception level of each cell measured by the second RSCP measurement section 501 when the P-CPICH reception level difference of each base station obtained by the first RSCP measurement section 209 is less than or equal to a threshold value. See the Primary
The cell determination unit 502 preferentially determines a cell having a high DPCCH reception level as a primary cell. By doing so, the demodulation performance can be improved.

Further, as shown in FIG. 6 in which parts corresponding to those in FIG. 2 are designated by the same reference numerals, the SIR (Signal to Interference Rati) of each cell is based on the output of each synchronous detection section 206.
An SIR measuring unit 601 that measures o) may be provided. The communication terminal device 600 includes an RSCP measuring unit 2
09, if the P-CPICH reception level difference of each base station obtained is less than or equal to a threshold value, the SIR of each cell measured by the SIR measurement unit 601 is referred to and the Primary c
The cell determining unit 602 preferentially sets the cell having a large SIR to P
It is determined as a primary cell. By doing so, the demodulation performance can be improved.

Further, as shown in FIG. 7 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, the error number measuring section 7 for measuring the error bit number of each cell based on the output of each synchronous detection section 206.
01 may be provided. This communication terminal device 70
When the P-CPICH reception level difference of each base station obtained by the RSCP measurement unit 209 is less than or equal to a threshold value, 0 refers to the error bit number of each cell measured by the error number measurement unit 701, and the primary cell The determination unit 702 gives priority to a cell having a small number of error bits in Primary.
Judge as cell. By doing so, the demodulation performance can be improved.

As described above, in the communication terminal device of the present invention, when selecting N primary cells, not only the P-CPICH reception level, but also the AFC error, the S-CPICH reception level, the DPCCH reception level, The SIR and the number of bit errors may be taken into consideration. In short, it is possible to determine a plurality of primary cells based on various elements that represent the reception quality of signals from each base station.

(Embodiment 3) In this embodiment, as in the case of Embodiment 2, based on the reception levels of signals received by a communication terminal from a plurality of base stations, the N highest order reception levels are selected. For primary base stations
In addition to creating an ID label indicating that it is ll and transmitting it to the base station, the SIR of the combined signal of the upper N base stations determined to be primary cells is obtained, and this S
The transmission power control signal is transmitted to the upper N base stations so that the IR becomes the target SIR. As a result, the probability of call disconnection can be further reduced, and unnecessary interference with other lines can be suppressed.

In FIG. 8 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, communication terminal apparatus 800 of this embodiment is shown.
2 has the same configuration as the communication terminal apparatus 200 of FIG. 2 except that the SIR measuring section 801 and the TPC generating section 802 are included.

The SIR measuring section 801 is provided for each synchronous detection section 20.
The SIR of each cell is measured based on the output of 6. TP
The C generation unit 802 generates a TPC bit from the SIR of each cell output by the SIR measurement unit 801, the determination result of the primary cell determination unit 210, and the target SIR.

Practically, the TPC generator 802 uses the SIR of each cell and the Primary cell information as a basis for the Pri
The SIR received from the mary cell is combined and the combined SIR is compared with the target SIR. As a result, the top N
SIRs of composite signals from a number of Primary cells
If it is determined that the quality is excessive, a TPC bit indicating that the transmission power is lowered is generated. On the contrary, if it is determined that the quality is insufficient, a TPC bit indicating that the transmission power is raised is generated.

As a result, the SIR is measured from the received signal of only the primary cell, and the transmission powers of the plurality of primary cells are controlled so that the SIR approaches the target value, so that the probability of call disconnection is further reduced. In addition, it is possible to suppress unnecessary interference with other lines.

Incidentally, ISCP (Interference Signal Co
de Power) is always measured for each cell, and RSCP is Pr
You may make it measure, when it is found to be an immediate cell. This is because RSCP can be measured instantaneously, but ISCP needs to perform averaging over multiple slots.

According to the above configuration, in addition to the configuration of the second embodiment, the transmission power is controlled in consideration of the combined SIR of N base stations determined to be primary cells. In addition to the effect of mode 2, it is possible to realize communication terminal apparatus 800 that can further reduce the probability of call disconnection and can suppress unnecessary interference components.

(Embodiment 4) In this embodiment, as in the case of Embodiment 2, based on the reception levels of signals received by a communication terminal from a plurality of base stations, the N highest-ranked reception levels are the highest. For primary base stations
In addition to creating an ID label indicating that it is 11 and transmitting it to the base station, transmission diversity control for reducing the phase difference between the antennas of the received signal for the upper N base stations determined to be primary cells is performed. I am supposed to do it.

That is, this embodiment is premised on that the base station performs transmission diversity in which the same signal is transmitted from a plurality of antennas. And the communication terminal is Pr
The FBI that minimizes the antenna phase difference when the base station signal is received is transmitted to the upper N base stations that have been determined to be the immediate cells. This allows the Primar
Since it is possible to improve the reception quality of the base station signal determined as y cell, it is possible to further reduce the probability of call disconnection.

In FIG. 9 in which parts corresponding to those in FIG. 2 are assigned the same reference numerals, communication terminal apparatus 900 of this embodiment
2 has the same configuration as the communication terminal apparatus 200 of FIG. 2 except that it has a phase difference measuring unit 901 and an FBI generating unit 902. Incidentally, the communication terminal device 200 of FIG.
Although it has a generation unit, in order to simplify the description in FIG.
The FBI generator is not shown.

The phase difference measuring section 901 includes the phase difference estimating section 2
Base station antenna # 0, antenna #
The inter-antenna phase difference for each cell is calculated from the phase estimation value of 1. FBI generation section 90 as phase control signal generation means
2 is P from the phase difference between antennas and primary cell information about each cell from the phase difference measuring unit 901,
An FBI bit that controls so that the inter-antenna phase difference for the primary cell is reduced is generated.

That is, as described in the first embodiment, the FBI is used for controlling the phase difference between the antennas when performing the transmit diversity together with the ID label information indicating whether the own station is the primary cell. Contains information. In this embodiment, the Primary c
FBI is generated so that the phase difference between the antennas at the time of receiving the base station signal determined to be
It transmits to the base station of Mary cell.

When changing the Primary cell, a new Primary cell is sent at the same timing as the FBI for transmitting the ID label of the changed Primary cell.
The FBI of the transmission diversity for the y cell may be transmitted, the FBI for the primary cell before the change may be transmitted, or the FBI considering both cells may be transmitted.

According to the above configuration, in addition to the configuration of the second embodiment, the FBI for reducing the phase difference between the antennas is formed for N base stations determined to be primary cells. In addition to the effect of 2, P
Since it becomes possible to further improve the reception quality from the primary cell, it is possible to realize the communication terminal apparatus 900 that can further reduce the probability of call disconnection.

[0072]

As described above, according to the present invention,
When performing site selection diversity transmission control, the base station refers to the past N (N is an integer of 1 or more) ID labels received from the communication terminal, and at least one of the N ID labels indicates the primary cell. , The mobile station determines that the upper N base stations with good reception quality are primary cells by operating as a primary cell (transmitting DPDCH in addition to DPCCH). By transmitting the ID label information indicating that the cell is a primary cell to each base station, it is possible to avoid the call disconnection even when the site selection diversity transmission control is performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a radio base station apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a configuration of a communication terminal device according to a second embodiment.

FIG. 3 is a block diagram showing another configuration example of the communication terminal apparatus according to the second embodiment.

FIG. 4 is a block diagram showing another configuration example of the communication terminal apparatus according to the second embodiment.

FIG. 5 is a block diagram showing another configuration example of the communication terminal apparatus according to the second embodiment.

FIG. 6 is a block diagram showing another configuration example of the communication terminal apparatus according to the second embodiment.

FIG. 7 is a block diagram showing another configuration example of the communication terminal apparatus according to the second embodiment.

FIG. 8 is a block diagram showing a configuration of a communication terminal device according to a third embodiment.

FIG. 9 is a block diagram showing a configuration of a communication terminal device according to a fourth embodiment.

FIG. 10 is a diagram for explaining site selection diversity transmission control.

[Explanation of symbols]

100 radio base station apparatus 104, 204a, 204b, 401 despreading section 105, 205 phase estimation section 106, 206 synchronous detection section 107, 207 RAKE combining section 109, 210, 302, 403, 502, 602, 7
02 Primary cell determination unit 109b Storage unit 112 Transmission power control unit 200, 300, 400, 500, 600, 700, 8
00, 900 Communication terminal devices 209, 402, 501 RSCP (Received Signal)
Code Power) Measuring Unit 301 AFC (Automatic Frequency Control) Error Measuring Units 601, 801 SIR (Signal to Interference Rat)
io) measuring unit 701 error number measuring unit 802 TPC (Transmit Power Control) generating unit 901 phase difference measuring unit 902 FBI (FeedBack Information) generating unit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Motoyasu Taguchi             3-1, Tsunashima-Higashi 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa             Matsushita Communication Industry Co., Ltd. (72) Inventor Shunji Junji             1-3 1-3 Nishinen, Kanazawa, Ishikawa Prefecture Stock Association             Company Matsushita Communication Kanazawa Research Center F term (reference) 5K022 EE01 EE11 EE21 EE31                 5K067 AA23 BB04 CC10 DD17 DD19                       EE02 EE10 EE24 FF02 HH23                       JJ35 JJ39 JJ52 JJ54 KK15

Claims (7)

[Claims] 1. A radio base station apparatus for use in a radio communication system configured to transmit a DPDCH signal only from a base station determined to be a primary cell by performing site selection diversity transmission control, the communication terminal being a communication terminal. Storage means for storing the past N number of ID label information received from, and even one of the N number of ID labels.
When the ID label indicating that the cell is a cell is included, a determination unit that determines that the own station is a Primary cell, and a determination unit that determines that the own station is a Primary cell, to the communication terminal DPDCH
A radio base station apparatus comprising: a transmitting unit that transmits a signal. 2. A communication terminal device for use in a wireless communication system configured to transmit a DPDCH signal only from a base station determined to be a primary cell by performing site selection diversity transmission control, and a plurality of base stations. The reception quality measuring means for measuring the reception quality of the signal from the station and the top N base stations in order from the highest reception quality
y cell, and a determining unit for determining the upper N base stations.
and a transmitting unit that transmits the ID label information indicating that the communication terminal device is 1. 3. The determination means determines the primary cell in consideration of the number of reception paths of the signal from each base station in addition to the reception quality of the signal from each base station. Item 2. The communication terminal device according to item 2. 4. The determining means is capable of performing the Prima at a certain point of time.
For the top N base stations determined to be ry cell,
When there is a base station having a reception quality that is higher than the reception quality of the upper N base stations at a later point in time, the difference between the reception quality and the reception quality of the upper N base stations selected previously is determined by a predetermined value. The communication terminal device according to claim 2, wherein the primary cell is not changed when the threshold value is equal to or less than the threshold value. 5. The determination means changes the number of base stations determined to be primary cells according to the magnitude of the difference in reception quality from each base station, the moving speed of the own station or the variation in reception quality. The communication terminal device according to claim 2, wherein 6. The determination unit further includes a Primer.
The SIR is calculated when the signals from the upper N base stations determined to be ry cells are combined, and a transmission power control signal to the upper N base stations is generated so that the SIR value approaches the target value. The communication terminal apparatus according to claim 2, further comprising a transmission power control signal generation unit. 7. The determination unit further includes a Primer.
Phase difference measuring means for measuring the inter-antenna phase difference of each base station signal based on the received signals from the upper N base stations determined to be ry cells, and the inter-antenna phase difference for the upper N base stations. 3. The communication terminal device according to claim 2, further comprising: a phase control signal generation unit that generates a phase control signal so that