JP3047393B2 - Base station transmission power control system, mobile station apparatus, and base station apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station transmission power control system, a mobile station apparatus, and a base station apparatus in a CDMA cellular mobile communication system to which soft handoff is applied.

[0002]

2. Description of the Related Art A code division multiple access (CDMA) cellular mobile communication system employs a base station transmission power control technique for controlling the transmission power of a signal transmitted from a base station apparatus based on power control information from the mobile station apparatus. Have been.

FIGS. 19 and 20 are control block diagrams of a mobile station and a base station for explaining a conventional general base station transmission power control method in a CDMA cellular mobile communication system.

First, control for transmitting power control information from a mobile station apparatus will be described with reference to FIG. In the mobile station, the transmission signal transmitted from the base station is transmitted and received by the duplexer B001, the RF unit B008, and the demodulation circuit B009.
The reception and demodulation are performed via the, and the reception quality measuring device B010 measures the reception quality Rq [dB]. Here, the reception quality is measured as a ratio between the base station transmission signal reception power and an undesired signal power such as interference, or a ratio between the reception power of the base station transmission signal and an arbitrary reference reception power constant. The processing unit B011 compares whether the measured reception quality Rq ′ is greater than a required quality Rth, and as a result of the comparison,
If the reception quality Rq ′ is higher than the required quality Rth, the processing unit B012 sets the transmission power control bit to 0; otherwise, the processing unit B013 sets the transmission power control bit to 1. The set transmission power control bits are inserted into transmission signal B007 in transmission power control bit insertion section B006, and overhead symbols including various control information and the like are inserted in overhead insertion section B005.

[0005] Transmission data including transmission power control bits and overhead information is transmitted to a spreader B004,
The signal is transmitted to the base station via the modulator / reception device and the amplifying device B002 via the transmission / reception sharing device.

Next, transmission power control in the base station apparatus based on power control information from the mobile station apparatus will be described with reference to FIG. A reception signal including various data and various control information from the mobile station is transmitted and received by the transmission / reception sharing device A001, the RF unit A
002, down converter A003, despreader A004
The signal is received and demodulated via a received data demodulator A005, and a transmission power control bit is extracted by a transmission power control bit detector A006. The processing unit A011 determines whether or not the value of the extracted transmission power control bit is 1, and if the transmission power control bit is 1, the processing unit A009 controls the transmission power control to be fixed to the current transmission power Pctl ′. The amount ΔP ′ is added. Otherwise, the transmission power control amount ΔP ′ is subtracted in the processing unit A010. The transmission spread RF signal A008 has the current transmission power Pct.
The signal is amplified by the variable output amplifier A007 having l 'as a control value, and is emitted to the mobile station via the transmission / reception sharing device A001.

As described above, the transmission power control according to the transmission power control block diagram achieves the base station transmission power control such that the reception quality at the mobile station becomes Rth.

[0008] The transmission power control method (hereinafter referred to as "method A")
That. Besides, several transmission power control schemes have been devised. For example, "Kikuchi, Higashi, Ohno, IEICE Technical Report, RCS 96-13, May 1996
Month, pp. In the transmission power control method (hereinafter, referred to as “method B”) described in “34.
The base station collects communication quality information of all connected mobile stations,
A method is proposed in which the transmission power is determined collectively so as to achieve the required quality. With this method, the desired transmission power can be pulled in at high speed, and excessive transmission power can be suppressed during the pulling time.

Also, "Hamabe, Yoshida, Gogawa, IEICE Technical Report, RCS 96-84, August 1996,
pp. 126, section 2.1 "(hereinafter, referred to as" method C "), the mobile station determines the amount of transmission power of the base station toward each mobile station by the pilot received power by itself. However, the base station has proposed a method of collectively determining the transmission power for each mobile station based on the allocation information. The method C does not aim at the transmission power control such that the reception quality at each mobile station becomes the required quality as at the methods A and B, but only aims at making the reception quality at all the mobile stations uniform. . Accordingly, although the interference suppression effect is considered to be lower than that of the system A, since the system refers to the pilot signal transmitted with a large power, stable control with high accuracy is possible.

By the way, in cellular mobile communication,
As the mobile station moves, switching (handoff) of the connected base station is performed. A mobile station in a CDMA cellular mobile communication system in which all base stations use the same frequency at the same time is always connected to the base station having the minimum propagation loss, and performs transmission power control to reduce interference with other radio lines. Must be kept to a minimum. However, the connection switching process to a new base station requires a certain amount of time, so that connection to the minimum propagation loss base station is delayed, and as a result, there is a disadvantage that communication with excessive transmission power is forced. Therefore, a method is adopted in which a mobile station connects to a plurality of base stations and takes in the minimum propagation loss base station in advance, which is called soft handoff.

With respect to the base station transmission power control in this method, a control method (hereinafter, referred to as “method D”) described in Japanese Patent Application Laid-Open No. 9-74378 (Claims 1 to 7) is known.
In method D, a method of distributing transmission power for each base station is such that the reception power from each base station in the mobile station is equalized, and the ratio of the reception power from each base station in the mobile station is the pilot reception level ratio. A method of distributing the transmission power of each base station to be equal to the ratio of the pilot reception level in the mobile station,
The above three methods are shown.

[0012]

A conventional downlink transmission power control system represented by the above-mentioned systems A to D, etc., employs a plurality of base station transmissions in which a plurality of base stations simultaneously transmit at the time of soft handoff. It is assumed. Soft handoff is an essential technology for realizing communication with the minimum propagation loss base station in a real system in which handoff control delay cannot be ignored, but for the downlink, a plurality of base stations are required to transmit to one mobile station. There is a problem that the interference to the mobile station is increased because of the necessity. Such a problem will be described with reference to FIGS.

FIG. 21 shows a zone Z which each of the base stations BS-A and BS-B defends during non-soft handoff.
FIGS. 3A and 3B illustrate the states of received signals received by the mobile stations when the mobile stations MS-A and MS-B are located, respectively. The mobile station MS-A receives a desired wave having a received power of PTd-A from the connected base station BS-A and an interference wave having a received power of PTi-B from the non-connected base station BS-B. On the other hand, the mobile station MS-B receives, from the connection base station BS-B, a desired wave whose received power is PTd-B and an interference wave whose received power is PTi-A from the base station BS-A. The ratio of the desired wave reception power to the interference wave reception power observed by the mobile station MS-B is PTd-B / PTi-A. Next, a case is considered in which the mobile station MS-A performs soft handoff with the base station BS-B while the mobile station is located in the same base station configuration as in FIG.

FIG. 22 shows the state of the received signals received by both mobile stations during soft handoff by mobile station MS-A. Mobile station MS-A during soft handoff
A desired signal from base station BS-A whose received power is PTd-A, and base station BS-B whose received power is PTd-A '
And two desired signals are received. A diversity gain can be obtained by the mobile station MS-A receiving diversity reception of both desired signal waves. On the other hand, the signal emitted by the base station BS-B for soft handoff with the mobile station MS-A is received by the mobile station MS-B as an interference wave. The mobile station MS of this interference wave
Assuming that the received power at -B is PTi-A ', the mobile station M
The ratio of the desired wave reception power to the interference wave reception power observed by SB is PTd-B / (PTi-A + PTi-A '). This is smaller than PTd-B / PTi-A, which is the ratio of the reception power of the desired wave to the reception power of the interference wave at the time of the non-soft handoff, and indicates that a decrease in reception quality due to an increase in interference occurs.

The mobile station MS-B can also perform a soft handoff to compensate for the quality degradation to some extent. However, comparing the increase in interference with the diversity gain due to site diversity, "Solei Manipore, Freeman, Proceeding of IEE.
E-Vehicle Technology Conference (M.Soleimanipor and GH Freeman, Proceeding of
IEEE Vehicular Technology Conference), pp. 11
According to the "29 right stage, 15th to 31st lines", the amount of increase in interference is larger, and as a result, the capacity of the downlink is limited. A similar claim can be found in "Nakano, Umeda, Ohno, IEICE Technical Report, RCS94-100, pp. 71, left column, line 1 to line 8".

The increase in the interference caused by the transmission of a plurality of base stations on the downlink does not cause a problem in a so-called hard handoff in which the simultaneous communication between the plurality of base stations and the mobile station is not performed. That is, the effect of the handoff control delay becomes a problem. According to "Furukawa, 1997 IEICE Communication Society Conference, pp. 264, Chapter 3" which examined the relationship between the amount of handoff control delay and the transmission power, the greater the handoff control delay, the greater the transmission power is released. That is stated. That is, hard handoff in a situation where the handoff control delay cannot be ignored forces the mobile station to communicate with the handoff source base station which is a non-minimum path loss base station. Communication must be performed with excessive transmission power, and eventually, interference given to nearby mobile stations increases.

(Object of the Invention) An object of the present invention is to suppress an increase in interference due to transmission of a plurality of base stations during soft handoff,
The purpose is to obtain a high downlink capacity.

Another object of the present invention is to prevent an excessive emission of transmission power due to a base station connection switching time at the time of handoff, that is, a handoff control delay.

[0019]

SUMMARY OF THE INVENTION A base station transmission power control system according to the present invention comprises a plurality of base stations each of which broadcasts a unique pilot signal, and a soft handoff base station group of several of the base stations. In a CDMA cellular mobile radio communication system including mobile stations that can be connected, only the main base station, which is a base station that minimizes propagation loss with the mobile station during soft handoff, transmits with appropriate power, and The base station other than the station performs transmission power control for transmitting with the suppressed power.

Further, the mobile station apparatus of the present invention provides a CDMA cellular mobile radio communication system which can be connected simultaneously with a group of several soft handoff base stations among a plurality of base stations each of which broadcasts a unique pilot signal. A mobile station apparatus, comprising: a call quality detecting means for detecting received call quality; a main base station detecting means for detecting a main base station having a maximum reception level among received pilots from a group of soft handoff base stations; Control signal transmission means for transmitting a transmission power control signal to the soft handoff base station group instructing transmission power control for the main base station based on quality and transmission power suppression control for soft handoff base station groups other than the main base station. It is characterized by having.

Further, the base station apparatus of the present invention broadcasts a unique pilot signal, and can be connected to a mobile station as a soft handoff base station simultaneously with another soft handoff base station in a CDMA cellular mobile radio communication system. A base station device, a control signal receiving unit that receives a transmission power control signal received from a mobile station device, and a control signal detection unit that detects main base station information and transmission power suppression information from the transmission power control signal. A power control unit that performs transmission power control based on the communication quality of the mobile station device when the main base station information indicates the own base station, and suppresses the transmission power when the main base station information indicates other than the own base station. It is characterized by having.

(Operation) By suppressing the transmission power of base stations other than the main base station at the time of soft handoff, an increase in downlink interference due to transmission of a plurality of base stations, which is a problem in soft handoff, is avoided. Also, by applying soft handoff, even when a handoff control delay exists, connection between the mobile station and the minimum path loss base station is guaranteed, and therefore, handoff due to handoff control delay, which is a problem in hard handoff, is considered. Excessive emission of the transmission power of the former base station is also avoided.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Explanation of Configuration) One embodiment of the base station transmission power control system, mobile station apparatus and base station apparatus of the present invention will be described below.

FIG. 1 is a diagram showing a configuration of the mobile station apparatus according to the present embodiment. The mobile station device includes an RF unit MS002 and a demodulation circuit MS003 that perform reception processing of a signal received from the base station device, a reception quality measuring device MS004 that detects a reception quality of a reception signal and a maximum pilot reception signal, and a pilot signal reception strength. Measuring device MS005, maximum pilot received signal detector MS006, transmission power control information symbol generation section PSC for generating base station transmission power control information to be inserted into a signal to be transmitted to the base station device, and transmission information for outputting a transmission signal A transmission power control information symbol insertion section MS012 for inserting a symbol of transmission power control information into a transmission signal; a spreader MS009 for inserting required overhead information and performing modulation processing and the like;
It comprises a modulator MS008, an amplifying device MS007, and a transmission / reception sharing device MS001.

The transmission signal emitted from the base station is received through the transmission / reception sharing device MS001, RF unit MS002, and demodulation circuit MS003 of the mobile station device, and is received by the reception quality measuring device MS
At 004, the reception quality Rq [dB] is measured. Further, the pilot signal emitted from each base station included in the output of the RF unit MS002 passes through a pilot signal reception strength measuring unit MS005, and is transmitted to a maximum pilot reception signal detector MS006, where the minimum propagation of the pilot having the maximum reception power is released. The lost base station index Bpmi is detected. Here, as the base station index, when the maximum number of soft handoff base stations is n, each soft handoff base station is assigned a different number among numbers 1 to n.

The reception quality Rq and the minimum path loss base station index Bpmi are input to the transmission power control information symbol generator PSC. The transmission power control information symbol generation section PSC generates a transmission power control information symbol Spct for designating a transmission signal level for the base station. Transmission power control information symbol Spct is inserted into transmission signal output from transmission information section MS011 in transmission power control information symbol insertion section MS012. Further, overhead information is inserted into the transmission signal output from overhead insertion section MS010 in overhead insertion section MS010. The transmission signal including the transmission information, the transmission power control information, and the overhead information includes a spreader MS009, a modulator MS008, an amplifying device MS007, and a transmission / reception sharing device M.
Released through S001 to the base station.

FIG. 2 is a diagram showing a configuration of the base station apparatus according to the present embodiment. The base station device demodulates a signal received from the mobile station device, and performs an RF unit BS002, a frequency downconverter BS003, and a despreader BS004.
And a reception data demodulator BS005, and a transmission power control symbol detector B for extracting transmission power control information for determining the output level of the RF signal transmitted by the base station apparatus from the reception signal
S006 and transmission power control section CTL, transmission spread RF signal section BS007 for outputting a transmission signal including a pilot signal to be released to the mobile station apparatus, and variable output amplifier for controlling the output level of the transmission signal based on transmission power control information BS
008 and a transmission / reception sharing device BS001.

The transmission signal including the transmission power control information released from the mobile station is transmitted to the base station by the transmission / reception sharing apparatus BS00.
1. RF section BS002, frequency down converter BS
003, despreader BS004, received data demodulator BS0
05, transmission power control information Spcr is detected by the transmission power control symbol detector BS006. The transmission power control information Spcr is input to the transmission power control unit CTL, and the transmission power control unit CTL transmits the transmission power control information Spcr.
Output level [d] of the variable output amplifier BS008 based on
BW] is set to the control value Pctl.

The transmission signal to the mobile station output from the transmission spread RF signal unit BS007 is amplified by the variable output amplifier BS008 controlled by the signal Pctl, and emitted to the mobile station via the transmission / reception sharing device BS001.

FIGS. 3 and 4 show a transmission power control information symbol generation unit PSC of the mobile station and a transmission power control unit CTL of the base station in the base station transmission power control system of the present invention.
1 is a flowchart showing one embodiment of the signal processing of FIG.

First, the operation of transmission power control information symbol generation section PSC in the mobile station shown in FIG. 3 will be described. In the control step PA001, the reception quality Rq measured by the mobile station is determined by a quality threshold value Rth [dB].
Is compared to As a result of comparison, if Rq> Rth, transmission power control information symbol Spct is set to 0 in control step PA002; otherwise, control step P
In A003, set Spct equal to Bpmi,
In control step PA004, any transmission power control information symbol Spct is output.

Next, the operation of transmission power control section CTL in the base station shown in FIG. 4 will be described. It is determined whether or not the transmission power control information Spcr detected by the transmission power control symbol detector BS006 is 0 in a control step CB001. Transmission power control information Spcr is 0
If not, the transmission power control amount (power increase amount) ΔPu [dB] is added to the current base station transmission power Pbsm [dBW] for the mobile station that emitted the transmission power control information Spcr in the control step CB002, while On the other hand, if the transmission power control information Spcr is 0, the transmission power control amount (power attenuation) ΔPd [dB] is subtracted from the base station transmission power Pbsm in the control step CB003.

When ΔPu is added to the base station transmission power Pbsm in control step CB002, it is checked in control step CB004 whether the transmission power control information Spcr matches the index number of the own base station.
If Spcr matches the index number of the own base station, transmission flag Fst is set to 1 in control step CB005, and if transmission power control information Spcr does not match the index number of the base station, transmission flag Fst is set to 0 in control step CB006. Set to. Here, it is assumed that the transmission flag Fst has an initial value of 0, and thereafter is always held until changed.

When ΔPu is subtracted from the current base station transmission power Pbsm in control step CB003, the previous value of the transmission flag Fst is used as it is.

In the control step CB007, the control value Pctl [dBW] of the output of the variable output amplifier BS008 shown in FIG. 1 is calculated by the following equation (1).

Pctl ← Pbsm × Fst + Pmin × (1−Fst) (1) Here, Pmin [dBW] represents the minimum transmission power in the base station.

In control step CB007, equation (1)
Is output to the variable output amplifier BS008, and the variable output amplifier BS008 controls the base station transmission power to the control value Pctl [dBW].

(Explanation of Operation) The operation of base station transmission power control during soft handoff in the base station transmission power control method of the present embodiment will be described with reference to FIGS. 5, 6, and 7.

As shown in FIG. 5, mobile station MS moving in the Cus direction has three base stations BS # 1, BS # 2, and BS #.
Assume that soft handoff is being performed with 3. The mobile station MS has the device configuration shown in FIG. 2, and constantly transmits the transmission power control information symbol Spct by the method shown in FIG.
1 to BS # 3. Also, the base station BS
Each of # 1 to BS # 3 has the device configuration shown in FIG. 1, and the output of the variable output amplifier BS008 is controlled to the control value Pctl by the method shown in FIG. Here, the power increase amount ΔPu and the power attenuation amount ΔPd have the same value.

Time transition of the transmission power of base stations BS # 1 to BS # 3 toward mobile station MS when the transmission power control method according to the present embodiment is applied is shown by a solid line in FIG. P-BS # 1, P-BS # 2 and P-BS # 3 are
This shows the time transition of the transmission power of the base stations BS # 1, BS # 2 and BS # 3, respectively. The vertical axis represents base station transmission power [dBW], and the horizontal axis represents time [sec].

In the transmission power control method according to the present embodiment, as shown by the solid line time transition P-BS # 2 in FIG. 6, the base station BS # 2 from time T0 [sec] to T1 [sec]. Are exclusively used for transmission, and base stations BS # 1, BS
# 3 performs transmission with the minimum transmission power. Further, from time T1 [sec] to T2 [sec], as shown in the time transition P-BS # 1, the base station BS # 1 exclusively performs transmission, and the base stations BS # 2 and BS # 3 have the minimum transmission. Transmission using transmission power is being performed.

As described above, according to the transmission power control method of the present embodiment, the main base station having the minimum propagation loss is always selected according to the reception level of the pilot signal received by the mobile station, and only the main base station is selected. The transmission wave is output, and the output of the transmission wave of another base station is suppressed, thereby suppressing an increase in interference.
This is apparently equivalent to a state in which instantaneous hard handoff without handoff control delay is realized.

FIG. 7 shows the transmission power of the base station when the transmission power control according to the prior art shown in FIGS. 19 and 20 is applied. C-BS # 1, C-BS # 2, and C-BS # 3 indicate time transitions of the transmission power of the base stations BS # 1, BS # 2, and BS # 3, respectively. In the transmission power control according to the conventional method, all the three base stations transmit the same transmission power to the mobile station MS as shown in FIG.
Higher interference will be exerted on peripheral mobile stations as compared with the transmission power control method of the present invention.

Further, in the sequential base station transmission power control based on the power adjustment instruction from the mobile station, an error occurs in the base station transmission power adjustment control due to a control signal reception error, which accumulates and causes excessive transmission output. You may fall.

According to the transmission power control of the present invention, even if an error occurs in the control of the base station transmission power, the influence can be reduced since the transmission power is suppressed except for the main base station.

(Other Embodiments of the Invention) Next, another embodiment of the base station transmission power control system, mobile station apparatus and base station apparatus of the present invention will be described.

FIG. 8 shows the configuration of a different embodiment of the base station apparatus of the present invention. In particular, FIG. 8 is a diagram showing a different configuration of the transmission power control unit CTL in the base station apparatus described with reference to FIG. . That is, transmission power control section C corresponding to transmission power control information symbol generation section PSC shown in FIG.
It relates to a different configuration of the TL.

In the present embodiment, a certain amount of transmission power increase / decrease control is performed depending on whether or not the transmission power control information symbol Spcr from the mobile station device matches the index number of the base station. The change in the transmission power of the base station apparatus due to the switching of the main base station can be made to have a gradual time transition as shown by the dotted line in FIG.

In transmission power control symbol detector BS006 of the base station shown in FIG. 1, control step CA001 is performed on transmission power control information symbol Spcr detected.
In step CA003, the transmission power control information symbol Spcr is compared with the index number of its own base station. If they are equal to each other, the control value Pctl [dBW] of the output of the variable output amplifier BS008 is increased by the power increase amount ΔPu [d
B], and if they are not equal, control step CA002
From the control value Pctl [dBW] to the power attenuation ΔP
The processing for subtracting d [dB] is performed. This addition or subtraction result Pctl [dBW] is output to the variable output amplifier BS008 in the control step CA004. The base station apparatus according to the present embodiment
And a mobile station apparatus having a transmission power control information symbol generation unit PSC shown in FIG. 1 and a base station transmission power control scheme of the present invention enabling a soft handoff operation.

Further, the present invention relates to a mobile station apparatus and a base station apparatus as still another embodiment of the present invention, and more particularly to a transmission power control information symbol generation section PSC and a transmission power control section C.
Different configurations of the TL will be described with reference to FIGS. In the present embodiment, the mobile station device manages the base station transmission power value to be emitted by the main base station, and constantly transmits the base station transmission power value and the minimum path loss base station index. In transmission power control information symbol generation section PSC shown in FIG. 9, reception quality Rq and constant quality threshold Rt
The setting is made so that the difference from h is reflected in the base station transmission power value.

First, the transmission power control information symbol generation unit P
The SC will be described.

FIG. 9 is a diagram showing a configuration of the transmission power control information symbol generation section PSC of the mobile station apparatus according to the present embodiment.

In control step PB001, a value obtained by subtracting quality threshold Rth from reception quality Rq [dB] measured at the mobile station is substituted for control amount ΔA [dB]. In control step PB002, ΔA is subtracted from the base station transmission power mobile station management value Pmbs [dBW]. In the control step PB003, the value of the base station transmission power mobile station management value Pmbs and the minimum path loss base station index Bpmi are combined to generate a transmission power control information symbol Sp.
ct, and the transmission power control information symbol Spct
With the transmission power control information symbol insertion section MS0 shown in FIG.
12 is output.

Next, the transmission power control unit CTL in the base station apparatus corresponding to the mobile station apparatus will be described.

FIG. 10 is a diagram showing a configuration of transmission power control section CTL of the base station apparatus corresponding to transmission power control information symbol generation section PSC shown in FIG.

First, in control step CC001, the minimum path loss base station index Bpmi and the base station transmission power mobile station management value Pmbs are separated. Next, in control step CC002, the minimum path loss base station index B
It is determined whether or not pmi is equal to its own base station index. If the minimum path loss base station index Bpmi is equal to the own base station index, control step CC003
Sets the control value Pctl of the variable output amplifier BS008 to the base station transmission power mobile station management value Pmbs, and if not equal, the control value Pct in the control step CC004.
1 is set to the minimum base station transmission power Pmin. afterwards,
In control step CC005, control value Pctl is output to variable output amplifier BS008.

According to the present embodiment, since the transmission power control is not performed sequentially according to the power adjustment instruction from the mobile station, the problem of accumulation of the base station transmission power adjustment error described above occurs. do not do.

Further, still another configuration of transmission power control symbol generation section PSC in the mobile station apparatus shown in FIG. 9 is shown in FIG.
It is shown in FIG. Also in the present embodiment, the mobile station apparatus constantly transmits the base station transmission power value and the minimum path loss base station index as in the case of transmission power control symbol generation section PSC shown in FIG. With respect to the setting of, a constant power control amount increase / decrease control is performed on the current transmission power value based on a comparison result between the reception quality Rq and the constant quality threshold Rth.

At control step PC001, the reception quality Rq [dB] measured at the mobile station is compared with quality threshold value Rth [dB]. If reception quality Rq is greater than quality threshold value Rth, control step PC003 returns. Current base station transmission power Mobile station management value Pmbs [dB
W] is subtracted from the power attenuation amount ΔPd [dB]. If the reception quality Rq is smaller than the quality threshold value Rth, in the control step PC002, the power increase amount ΔPu [dB] is added to the current base station transmission power mobile station management value Pmbs [dBW]. The value of the base station transmission power mobile station management value Pmbs is combined with the minimum path loss base station index Bpmi in the control step PC002 and output as the transmission power control information symbol Spct. The mobile station apparatus of the present embodiment is configured with the base station apparatus having the transmission power control unit CLT shown in FIG. 10 and the base station transmission power control method of the present invention that enables a soft handoff operation.

As still another embodiment of the present invention, different configurations of a transmission power control information symbol generation unit PSC and a transmission power control unit CTL will be described, particularly for a mobile station device and a base station device. Although the present embodiment described above relates to a base station power transmission scheme that employs a configuration in which a mobile station apparatus constantly transmits a minimum path loss base station index to a base station apparatus, the following embodiments are: The minimum path loss base station index is intermittently transmitted.

FIG. 12 relates to a mobile station apparatus showing an embodiment in which the minimum path loss base station index is intermittently transmitted. In particular, transmission power control in which the minimum path loss base station index is transmitted only when it changes. Symbol generator P
It is a figure showing composition of SC.

In control step PC001, reception quality Rq [dB] measured at the mobile station is compared with quality threshold value Rth. As a result of the comparison, the reception quality Rq [d
If B] is larger than the quality threshold Rth [dB], the transmission power control bit Pbt is set to 0 in the control step PC002, and the reception quality Rq [dB] is smaller than the quality threshold Rth [dB]. If so, in the control step PC003, the transmission power control bit Pbt is set to 1. Next, in the control step PC004, the minimum path loss base station index Bpmi is referred to, and if it is equal to the previous minimum path loss base station, the control step PC005
, The transmission power control information symbol Spct is set to a value equal to Pbt, and the 1-bit transmission power control information symbol Spct is set to the transmission power control information symbol insertion section M in FIG.
Output to S012. On the other hand, if there has been a change from the previous minimum propagation loss base station, the transmission power control information symbol Spct is set in control step PC006 according to the following equation (2), and the transmission power control information symbol Spct of 2 bits or more is set in FIG. Transmission power control information symbol insertion section M
Output to S012.

Spct = 2 × Bpmi + Pbt (2) In the present embodiment, the base station index Bpmi is included in the transmission power control information symbol Spct for 2 bits or more only when the minimum path loss base station is changed. Is transmitted, and if there is no change in the minimum propagation loss base station, the transmission amount of the transmission power control information is reduced by transmitting only the control bit consisting of 1 bit to the base station. It is possible.

FIG. 13 is a diagram showing a configuration of transmission power control section CTL in the base station apparatus of the present invention corresponding to transmission power control information symbol generation section PSC shown in FIG.

In this embodiment, first, in control step CD001, transmission power control information Spcr is set to 2
It is determined whether it is composed of bits or more. If the transmission power control information Spcr is 2 bits or more, in the control step CD002, the control bit Pbt and the minimum path loss base station index Bsi are obtained according to the following equations (3) and (4).

Pbt = Spcr mod 2 (3) Bsi = int (Spcr / 2) (4) where X mod Y is a value obtained by dividing X by Y, and int (X) is X. Represents the truncated integer conversion of.
Equations (3) and (4) correspond to processing for separating the two control bits.

In control step CD002, Pbt,
After acquiring Bsi, it is checked in control step CD004 whether the minimum path loss base station index Bsi is equal to the own base station index. If the minimum path loss base station index Bsi is equal to the own base station index, the transmission flag Fst
Is set to 1; if not equal, control step CD006
Sets the transmission flag Fst to 0. Here, the initial value of the transmission flag Fst is set to 0, and the set transmission flag is held until the next change.

On the other hand, if it is determined in the control step CD001 that the transmission power control information Spcr is not composed of 2 bits or more, the control bit Pbt is set equal to the value of the transmission power control information Spcr in the control step CD003. As the value of the transmission flag Fst after the control step CD003, the previous value is used as it is.

Next, it is determined in a control step CD007 whether or not the control bit Pbt is 0, and if it is 0, in the control step CD009, the base station transmission power Pb
The power attenuation amount ΔPd [dB] is subtracted from sm [dBW]. If the transmission power control information Spcr is not 0, in the control step CD008, the base station transmission power Pbsm [dB]
W] is added to the power increase amount ΔPu [dB]. The control value Pctl [dBW] of the variable output amplifier BS008 is calculated by the equation (1) in the control step CD010 and output to the variable output amplifier BS008.

FIG. 14 shows a different embodiment of the mobile station apparatus for intermittently transmitting the minimum path loss base station index shown in FIG. 12, and in particular, the base station transmission power control section shown in FIG. 9 shows a different configuration of a transmission power control information symbol generation unit PSC corresponding to CTL. In the present embodiment, the transmission power of the main base station is periodically reviewed, and the minimum path loss base station index is periodically transmitted.

In control step PD001, reception quality Rq [dB] measured at the mobile station is compared with quality threshold value Rth. As a result of the comparison, the reception quality Rq [d
If B] is larger than the quality threshold value Rth [dB], the transmission power control bit Pbt is set to 0 in the control step PD002, and the reception quality Rq [dB] is smaller than the quality threshold value Rth [dB]. If so, in the control step PD003, the transmission power control bit Pbt is set to 1. Next, in the control step PD004, it is determined whether or not the current time is the review time of the main base station. If the current time is the review time of the main base station, the transmission power control information symbol Spct according to the equation (2) in the PD006 is determined.
Is set, and if the current time is not the review time of the main base station, P
In D005, the transmission power control information symbol Spct is set equal to Pbt. PD005 or PD00
6. The transmission power control information symbol SPCT determined by
Is output to transmission power control information symbol insertion section MS012 in FIG.

FIG. 15 shows a different configuration of transmission power control section CTL of the base station apparatus corresponding to transmission power control information symbol generation section PSC shown in FIG. 12 or FIG. In the present embodiment, transmission power control value Pct
As l, a constant power control amount increase / decrease control is performed on the current control value and output.

At control step CE001, it is determined whether or not transmission power control information Spcr is composed of two or more bits. If the transmission power control information Spcr is 2 bits or more, the control bit Pbt and the minimum path loss base station index Bsi are obtained in the control step CE002 according to the equations (3) and (4). After acquiring Pbt and Bsi in the control step CE002,
In the control step CE004, it is checked whether or not the minimum path loss base station index Bsi is equal to the own base station index. If the minimum path loss base station index Bsi is equal to the own base station index, control step CE0
05, the transmission flag Fst is set to 1, and if not equal, the transmission flag Fs is set in the control step CE006.
Set t to 0. Here, the initial value of the transmission flag Fst is set to 0, and the set value of the transmission flag is always held until the next change.

On the other hand, when it is determined in the control step CE001 that the transmission power control information Spcr is not two bits or more, the control bit Pbt is set equal to the value of the transmission power control information Spcr in the control step CE003. As the value of the transmission flag Fst after the control step CE003, the previous value is used as it is.

Next, in control step CE007, P
It is determined whether or not bt is 1, and if it is 1, it is further determined in control step CE008 whether or not Fst is 1. If both the control bit Pbt and the transmission flag Fst are 1, in the control step CE009, the base station transmission power Pbsm [dBW] includes the power increase ΔPu [d
B], otherwise control step CE010
In, the power attenuation ΔPd [dB] is subtracted from the base station transmission power Pbsm [dBW]. Control step CE01
At 1, the value of the base station transmission power Pbsm is assigned to Pctl and output to the variable output amplifier BS008.

A mobile station apparatus having transmission power control information symbol generation section PSC shown in FIG. 12 or FIG.
Alternatively, the base station apparatus having the transmission power control unit CTL shown in FIG. 15 constitutes the base station transmission power control method of the present invention.

As still another embodiment of the present invention, the present invention relates to a mobile station apparatus and a base station apparatus, and more particularly, to a transmission power control information symbol generation section PSC and a transmission power control section CTL.
Will be described.

FIG. 16 relates to a different embodiment of the mobile station apparatus of the present invention.
It is a figure showing composition of C. This embodiment is based on the premise that the base station operates synchronously with the base station apparatus. Normally, only control information for instructing an increase or decrease of the transmission power of the base station is transmitted as a transmission power control signal, and the main base station is periodically Only station information is transmitted as a transmission power control signal.

In control step PE001, the reception quality Rq [dB] measured at the mobile station is compared with a quality threshold Rth. As a result of the comparison, the reception quality Rq [d
If B] is larger than the quality threshold value Rth [dB], the transmission power control bit Pbt is set to 0 in the control step PE002, and the reception quality Rq [dB] is smaller than the quality threshold value Rth [dB]. If so, in the control step PE003, the transmission power control bit Pbt is set to 1. Next, in the control step PE004, it is determined whether or not the current time is the review time of the main base station. If the current time is the review time of the main base station, the transmission power control information symbol Spct is replaced with the minimum propagation loss base station index Bpmi in PE006. The transmission power control information symbol Spct is set to be equal to Pbt in PE005 if the current time is not the review time of the main base station. The transmission power control information symbol Spct determined by PE005 or PE006 is output to the transmission power control information symbol insertion section MS012 in FIG.

FIG. 17 is a diagram showing the configuration of transmission power control section CTL in the base station apparatus of the present invention corresponding to transmission power control information symbol generation section PSC shown in FIG. In the present embodiment, control of transmission power suppression is performed in synchronization with main base station information periodically transmitted from the mobile station apparatus, and a control value Pctl is output.

First, in control step CF001,
It is determined whether or not the current time is the review time of the main base station. Here, it is assumed that the review times of the mobile station apparatus, the base station apparatus, and the respective main base stations are synchronized with each other. If it is determined in the control step CF001 that the current time is not the review time of the main base station, the transmission power control bit Pbt is set equal to the transmission power control information symbol Spcr in the control step CF003, and the Pbt is set to 0 in the control step CF007. It is determined whether or not there is. If Pbt is 0, control step CF00
In 9, the power attenuation ΔPd [dB] is subtracted from the base station transmission power Pbsm [dBW]. If Pbt is not 0, in control step CF008 the base station transmission power P
The power increase ΔPu [dB] is added to bsm [dBW].

Control step CF005 or CF00
After determining the base station transmission power Pbsm according to 6, the control value Pctl [dBW] of the variable output amplifier BS008 is calculated by the equation (1) in the control step CF010,
The control value Pctl is output to the variable output amplifier BS008 in FIG.

On the other hand, if it is determined in the control step CF001 that the current time is the review time of the main base station, the minimum propagation loss base station index Bsi is set to the transmission power control information symbol Spc in the control step CF002.
r, and whether or not the base station index of the own station is equal to Bsi is determined in control step CF004. If it is determined in CF004 that Bsi is equal to its own base station index, CF00
In step 5, the transmission flag Fst is set to 1; otherwise, Fst is set to 0 in CF006. Here, the initial value of the transmission flag Fst is set to 0, and the set transmission flag is held until the next change. After the transmission flag Fst is determined by CF005 or CF006,
Control value Pctl [dBW] of variable output amplifier BS008
Is calculated by the equation (1) in the control step CF010, and Pctl is output to the variable output amplifier BS008 in FIG.

FIG. 18 shows another embodiment of the base station apparatus of the present invention. In particular, the transmission power control section C corresponding to the transmission power control symbol generation section PSC shown in FIG.
It shows a different configuration of the TL. In this embodiment,
The control value Pct1 of the transmission power is subjected to a constant power control amount increase / decrease control with respect to the current control value.

In control step CG001, it is determined whether or not the current time is the time for reviewing the main base station. Here, it is assumed that the review times of the mobile station apparatus, the base station apparatus, and the respective main base stations are synchronized with each other. If it is determined in the control step CG001 that the current time is the review time of the main base station, in the control step CG002, the minimum path loss base station index BSi is set equal to the transmission power control information symbol Spcr, and the base station of the own station is further set. In the control step CG004, it is determined whether or not the index is equal to Bsi. In CG004, if it is determined that Bsi is equal to its own base station index, the transmission flag Fst is set to 1 in CG005; otherwise, Fs is set in CG006.
Set t to 0. Here, the initial value of the transmission flag Fst is set to 0, and the set transmission flag is held until the next change.

Control step CG005 or CG00
After the transmission flag Fst is determined by step 6, the control value Pctl [dBW] of the variable output amplifier BS008 is set equal to Pbsm in the control step CG011, and the control value Pctl is output to the variable output amplifier BS008 of FIG.

On the other hand, if it is determined in the control step CG001 that the current time is not the review time of the main base station, the transmission power control bit Pbt is set equal to the transmission power control information symbol Spcr in the control step CG003. Control step CG00
The determination is made at 7.

If Pbt is determined not to be 1 in control step CG007, power attenuation ΔPd [dB] is subtracted from base station transmission power Pbsm [dBW] in control step CG010. If Pbt is determined to be 1 in CG007, it is determined whether or not the transmission flag Fst is 1 in a control step CG008.
If st is not 1, in control step CG010, power attenuation △ Pd from base station transmission power Pbsm [dBW].
[DB] is reduced. If Fst is 1, control step C
In G009, the power increase ΔPu [dB] is added to the base station transmission power Pbsm [dBW]. Control step C
Base station transmission power Pb according to G009 or CG010
After the determination of sm, the control value Pctl [dBW] of the variable output amplifier BS008 in the control step CG011.
Is set equal to Pbsm, and the control value Pctl is output to the variable output amplifier BS008 in FIG.

Mobile station apparatus having transmission power control information symbol generator PSC shown in FIG. 16, and FIG. 17 or FIG.
The base station apparatus having the transmission power control unit CTL shown in FIG.

[0090]

According to the transmission power control method of the present invention, by suppressing the output of base stations other than the main base station that minimizes the propagation loss with the mobile station, the transmission power control method can be reduced compared to the conventional transmission power control method. Interference to peripheral mobile stations is reduced, and as a result, a high downlink capacity can be obtained.

Also, by suppressing the transmission power of base stations other than the main base station during soft handoff, an increase in downlink interference due to transmission of a plurality of base stations, which is a problem in soft handoff, can be avoided.

Furthermore, since the transmission power control method of the present invention is based on the premise that soft handoff is applied, even when a handoff control delay exists, connection between the mobile station and the minimum propagation loss base station is guaranteed. In the hard handoff, the excessive emission of the transmission power of the handoff source base station due to the problematic handoff control delay is also avoided.

[0093]

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a mobile station device according to the present invention.

FIG. 2 is a diagram illustrating an embodiment of a base station device according to the present invention.

FIG. 3 is a diagram illustrating a generation unit of transmission power control information in the mobile station device according to the present embodiment.

FIG. 4 is a diagram illustrating a transmission power control unit in a base station device for the mobile station device illustrated in FIG. 3;

FIG. 5 is a diagram showing a cellular mobile station arrangement for explaining a soft handoff operation of the present invention.

FIG. 6 is a diagram illustrating a time transition of transmission power of the base station device according to the present invention.

FIG. 7 is a diagram illustrating a time transition of transmission power of a base station device according to the related art.

8 is a diagram illustrating a transmission power control unit of a base station device according to another embodiment of the mobile station device illustrated in FIG.

FIG. 9 is a diagram illustrating a transmission power control unit of a mobile station device according to another embodiment of the present invention.

FIG. 10 is a diagram illustrating a transmission power control information generation unit of a base station apparatus according to another embodiment for the mobile station apparatus illustrated in FIG. 9;

11 is a diagram illustrating a transmission power control information generation unit of a mobile station device according to another embodiment of the mobile station device shown in FIG.

FIG. 12 is a diagram illustrating a transmission power control information generation unit of a mobile station device according to another embodiment of the present invention.

13 is a diagram illustrating a transmission power control unit of a base station device according to another embodiment for the mobile station device illustrated in FIG.

14 is a diagram illustrating a transmission power control unit of a mobile station device according to another embodiment of the mobile station device illustrated in FIG.

FIG. 15 is a diagram illustrating a transmission power control unit of the base station apparatus according to another embodiment of the base station apparatus shown in FIG.

FIG. 16 is a diagram showing a transmission power control information generation unit of a mobile station device according to another embodiment of the mobile station device shown in FIG. 12 or FIG.

FIG. 17 is a diagram illustrating a transmission power control unit of a base station apparatus according to another embodiment of the base station apparatus shown in FIG. 13 or FIG.

FIG. 18 is a diagram illustrating a transmission power control unit of a base station apparatus according to another embodiment of the base station apparatus illustrated in FIG. 13, FIG. 15, or FIG.

FIG. 19 is a configuration diagram of a mobile station device according to the related art.

FIG. 20 is a configuration diagram of a base station device according to the related art.

FIG. 21 is a diagram illustrating signals received by a mobile station when soft handoff is not performed.

FIG. 22 is a diagram illustrating signals received by the mobile station when soft handoff is performed.

[Explanation of symbols]

A001 Transmission / reception shared device A002 RF unit A003 Down converter A004 Despreader A005 Received data demodulator A006 Transmission power control bit detector A007 Variable output amplifier A008 Transmission spread RF signal A011 Transmission power control bit BS001 Transmission / reception shared device BS002 RF unit BS003 Downconverter BS004 Despreader BS005 Received data demodulator BS006 Transmission power control symbol detector BS007 Despread RF signal unit BS008 Variable output amplifier CTL Transmission power control unit B001 Transmission / reception shared device B002 Amplification device B003 Modulator B004 Spreader B005 Overhead insertion unit B006 Transmission Power control bit insertion section B007 Transmission signal B008 RF section B009 Demodulation circuit B010 Reception quality measuring instrument MS001 Transmission / reception shared equipment MS002 RF section MS003 Demodulation circuit MS004 Reception quality measurement instrument MS005 Pilot signal reception strength measurement apparatus MS006 Maximum pilot reception signal detector MS007 Amplification device MS008 Modulator MS009 Spreader MS010 Overhead insertion section MS011 Transmission information section MS012 Transmission power control information symbol insertion section Spcr transmission power control information Pbsm base station transmission power [dBW] ΔPd, ΔPu, ΔP ′, ΔA transmission power control amount [d
B] Fst Transmission flag Pctl Control value of variable transmission amplifier [dBW] Pmin Base station minimum transmission power [dBW] CTL Base station transmission power control unit Rq Mobile station quality measurement value [dB] Bpmi Minimum propagation loss base station index Spct Transmission power Control symbol PSC Transmission power control information symbol generation unit Pmbs Base station transmission power management value [dB] in mobile station
W] Pbt Transmission power control bit Bsi Minimum path loss base station index received by base station

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B ⁷ /24-7/26 H04J 13/00-13/06 H04Q 7/00-7/38

Claims (25)

(57) [Claims] 1. A CDMA cellular mobile radio comprising a plurality of base stations each of which broadcasts a unique pilot signal, and mobile stations which can be connected simultaneously with a group of soft handoff base stations of several of the base stations. A base station transmission power control method in a communication system, wherein soft handoff base stations other than the main base station that minimize the propagation loss with a mobile station during soft handoff perform transmission while suppressing output. 2. The base station transmission power control method according to claim 1, wherein the main base station controls transmission power according to an instruction from the mobile station. 3. The mobile station uses a soft hand-off base station having a maximum reception level among the received pilot signals as the main base station, and sets the transmission power of the main base station to a desired reception communication quality in the mobile station. 3. The base station transmission power control method according to claim 2, wherein the control is performed such that 4. A CDMA cellular mobile radio comprising a plurality of base stations each of which broadcasts a unique pilot signal, and mobile stations which can be connected simultaneously with a group of soft handoff base stations of several of the base stations. In the communication system, the mobile station detects a received call quality and a main base station having a maximum pilot reception level among reception levels of pilot signals from the soft handoff base station group, and transmits to the soft handoff base station group. As a power control signal, if the received call quality does not exceed the desired quality, the base station number of the main base station is notified, and if it exceeds, a number other than the base station number of the soft handoff base station group is notified, Each base station of the soft handoff base station group receives the transmission power control signal, and indicates the content indicated by the transmission power control signal. Base station transmission power control scheme if not the base station number of its own station, characterized in that to suppress the transmission power. 5. Each base station of the soft handoff base station group manages two transmission power values, and with respect to the first transmission power value, the content of the transmission power control signal is If it indicates other than the base station number, it is decreased, if the content of the transmission power control signal indicates any of the base station numbers of the soft handoff base station group, it is increased, and the second transmission power value is the second transmission power value. One transmission power value or the minimum transmission power value is selected and set, and if the content of the transmission power control signal indicates the base station number of the own station, the first transmission power value is used as the second transmission power value. Set the value,
If the content of the transmission power control signal indicates the base station number of the soft handoff base station group other than the own station, the minimum transmission power value is set as the second transmission power value, and the transmission power control signal If the contents indicate other than the base station number of the soft handoff base station group and the first transmission power value was previously set as the second transmission power value, the first transmission power value was used as the second transmission power value. Set the transmit power value,
If the content of the transmission power control signal indicates other than the base station number of the soft handoff base station group and the last time set the minimum transmission power value as the second transmission power value, the second transmission power value Set the minimum power value as
5. The base station transmission power control method according to claim 4, wherein said second transmission power value is an output value of a transmission amplifier. 6. The base station of the soft handoff base station group increases the transmission power when the transmission power control signal indicates the base station number of the base station, and the base station of the soft handoff base station The transmission power control method according to claim 4, wherein the transmission power is reduced when the base station number of the base station is not represented. 7. A CDMA cellular mobile radio comprising a plurality of base stations each of which broadcasts a unique pilot signal, and mobile stations which can be connected simultaneously with a group of soft handoff base stations of several of the base stations. In the communication system, the mobile station manages a base station transmission power value, and detects a main base station having a maximum pilot reception level among received speech quality and reception levels of pilot signals from the soft handoff base station group. Adjusting the base station transmission power value managed by the mobile station so that the received call quality is a desired quality, and comprising a base station number of the main base station and the base station transmission power value. Transmitting a control signal to the soft handoff base station group; each base station in the soft handoff base station group receiving the transmission power control signal; If the base station number included in the control signal matches the base station number, the base station transmission power value managed by the mobile station included in the transmission power control signal is set as the transmission power value of the own station, and the base station A base station transmission power control method, wherein a minimum transmission power value is set as the transmission power value of the own station if the number and the own base station number do not match. 8. The base station transmission power control method according to claim 7, wherein said mobile station adjusts said base station transmission power value by an amount of difference between said received communication quality and said desired quality. 9. The mobile station compares the received call quality with the desired quality, and reduces the base station transmission power value managed by the mobile station if the received call quality exceeds the desired quality. 8. The base station transmission power control method according to claim 7, wherein the base station transmission power value managed by the mobile station is increased if the received communication quality does not exceed the desired quality. 10. A CDMA cellular mobile radio comprising a plurality of base stations each of which broadcasts a unique pilot signal, and mobile stations which can be connected simultaneously with a group of soft hand-off base stations of several of the base stations. In the communication system, the mobile station detects a received speech quality and a main base station having a maximum pilot reception level among reception levels of pilot signals from the soft handoff base station group, and the received speech quality indicates a desired quality. If not, a power increase symbol is set in the transmission power control bit, and if the received speech quality exceeds the desired quality, a power decrease symbol is set in the transmission power control bit, and the transmission power is set to the soft handoff base station group. Transmitting the control bits and intermittently transmitting the primary base station number; The base station receives the transmission power control signal, and if the transmission power control signal does not include the main base station number and does not match the base station number of the base station, suppresses the transmission power of the base station after the current time. A base station transmission power control method. 11. The transmission power control comprising the main base station number and the transmission power control bit only when a change occurs in the main base station determined from the maximum pilot reception level. Transmitting a signal to the soft handoff base station group, and transmitting a transmission power control signal consisting of only the transmission power control bit to the soft handoff base station group when the main base station is not changed. The base station transmission power control method according to claim 10, wherein 12. The mobile station transmits a transmission power control signal consisting of only the transmission power control bit to the soft handoff base station group, and periodically transmits the main base station number and the transmission power control bit. The base station transmission power control method according to claim 10, wherein a transmission power control signal composed of the following is transmitted to the soft handoff base station group. 13. The base station of the group of soft handoff base stations manages two transmission power values, and adjusts a first transmission power value according to the transmission power control bit included in the transmission power control signal. If the main base station number is included in the transmission power control signal and matches the own base station number, the first transmission power value is set as the second transmission power value after the current time, and the main transmission power control signal If the base station number is included and does not match the own base station number, the minimum transmission power is set as the second transmission power value after the current time, and the second transmission power value is set to the output value of the transmission amplification device. 11. The base station transmission power control method according to claim 10, wherein: 14. The base station of the soft handoff base station group, if the transmission power control signal includes a main base station number and matches the own base station number, the base station controls the transmission power after the present time to the transmission power control signal. The base station number is included in the transmission power control signal, and if the transmission power control signal does not match the own base station number, the transmission power after the current time is set to the transmission power control bit. 11. The base station transmission power control method according to claim 10, wherein the base station transmission power control method is used to reduce the transmission power. 15. A CDMA cellular mobile radio comprising a plurality of base stations each of which broadcasts a unique pilot signal, and a mobile station which can be connected simultaneously with a group of soft handoff base stations of several of said base stations. In the communication system, the mobile station detects a received speech quality and a main base station having a maximum pilot reception level among reception levels of pilot signals from the soft handoff base station group, and the received speech quality indicates a desired quality. If not, a power increase symbol is set in the transmission power control bit, and if the received communication quality exceeds the desired quality, a power reduction symbol is set in the transmission power control bit, and the transmission configured by the transmission power control bit is set. Transmitting a power control signal or a transmission power control signal composed of the main base station number to the soft handoff base station group; Each base station of the soft handoff base station group receives the transmission power control signal, the content of the transmission power control signal indicates the main base station number, and the main base station number is the base station of the own station. A base station transmission power control method characterized in that if it does not match the station number, the transmission power of the own station after the current time is suppressed. 16. The base station of the soft handoff base station group manages two transmission power values, and when the content of the transmission power control signal indicates the transmission power control bit, the base station performs the second transmission power control according to the transmission power control bit. One transmission power value, if the content of the transmission power control signal indicates the main base station number and the main base station number matches the base station number of the own station, the second transmission power value after the current time As the first transmission power value, the contents of the transmission power control signal indicates the main base station number and the main base station number if the base station number does not match the base station number of the second station after the current time The base station transmission power control method according to claim 15, wherein a minimum transmission power value is set as a transmission power value, and the second transmission power value is used as an output value of a transmission amplifier. 17. The base station of the soft handoff base station group, if the content of the transmission power control signal indicates a main base station number and the main base station number matches its own base station number, The transmission power is adjusted according to the transmission power control bit, and if the content of the transmission power control signal indicates a main base station number and the main base station number does not match the own base station number, the transmission power after the current time is set to the transmission power. 16. The base station transmission power control method according to claim 15, wherein the transmission power control bit is decreased regardless of the transmission power control bit. 18. A mobile station apparatus in a CDMA cellular mobile radio communication system which can be connected simultaneously with a soft handoff base station group composed of several stations among a plurality of base stations each broadcasting a unique pilot signal. Reception quality detection means for detecting the received call quality, a main base station detection means for detecting a main base station having a maximum reception level among received pilot signals from the soft handoff base station group, and the reception quality detection means When the detected received call quality does not exceed the required quality, the main base station information detected by the main base station detecting means is determined as a transmission power control signal for the soft handoff base station group, and detected by the receiving quality detecting means. If the received call quality exceeds the required quality, the base station transmission power decrease information is soft handed off. Transmission power control signal determination means for determining as a transmission power control signal for a group of base stations, and control signal transmission means for transmitting the transmission power control signal determined by the transmission power control signal determination means to the soft handoff base station group; A mobile station device comprising: 19. A base station apparatus in a CDMA cellular mobile radio communication system capable of broadcasting a unique pilot signal and connecting simultaneously with another soft handoff base station as a soft handoff base station with the mobile station. Control signal receiving means for receiving a transmission power control signal from a station device, control signal detection means for detecting main base station information or base station transmission power reduction information from the transmission power control signal, and detection by the control signal detection means A transmission power control unit that suppresses transmission power when the transmitted transmission power control signal does not indicate base station information of the own station. 20. A mobile station apparatus in a CDMA cellular mobile radio communication system capable of being connected simultaneously with a soft handoff base station group composed of several stations among a plurality of base stations each broadcasting a unique pilot signal. Receiving quality detection means for detecting received call quality, main base station detecting means for detecting a main base station having a maximum reception level among received pilot signals from the soft handoff base station group, and base station transmission power value. Hold, increase the base station transmission power value when the received speech quality detected by the reception quality detection means does not exceed the required quality, and when the received speech quality detected by the reception quality detection means exceeds the required quality. Base station transmission power management means for reducing the base station transmission power value, and a main base station detected by the main base station detection means A control signal transmitting unit for transmitting information and the base station transmission power value held by the base station transmission power management unit as a transmission power control signal to the soft handoff base station group; . 21. A base station apparatus in a CDMA cellular mobile radio communication system capable of broadcasting a unique pilot signal and being connected to a mobile station as a soft handoff base station simultaneously with another soft handoff base station. Control signal receiving means for receiving a transmission power control signal from a station device, control signal separation means for separating main base station information and base station transmission power value information from the transmission power control signal, and the control signal separation means When the separated main base station information indicates the base station information of the own station, transmission is performed using the base station transmission power indicated by the base station transmission power value information, and the main signal detected by the control signal separation unit is transmitted. Transmission power control means for performing transmission with the minimum transmission power when the base station information does not indicate its own base station information. Base station apparatus. 22. A mobile station apparatus in a CDMA cellular mobile radio communication system which can be connected simultaneously with a soft handoff base station group composed of several stations among a plurality of base stations each broadcasting a unique pilot signal. Reception quality detection means for detecting the received call quality, a main base station detection means for detecting a main base station having a maximum reception level among received pilot signals from the soft handoff base station group, and the reception quality detection means If the detected received call quality does not exceed the required quality, the power increase is set in the base station transmission power control signal, and if the received call quality detected by the reception quality detecting means exceeds the required quality, the power decrease is transmitted to the base station. Base station transmission power control signal determining means to be set in the power control signal, and the base station control signal determining means The base station transmission power control signal is transmitted to the base station group during the soft handoff, or is determined intermittently by the main base station information detected by the main base station detection means and the base station control signal determination means. A control signal transmitting means for transmitting the base station transmission power control signal to a base station group in the soft hand. 23. A base station apparatus in a CDMA cellular mobile radio communication system capable of broadcasting a unique pilot signal and being simultaneously connected to a mobile station as another soft handoff base station as a soft handoff base station. Control signal receiving means for receiving a transmission power control signal from a station device, and a main base station for separating the transmission power control signal and the main base station information when the transmission power control signal includes main base station information Information separating means, and when the main base station information is included in the transmission power control signal and the main base station information indicates the base station information of the own station, the transmission power after the current time is determined according to the transmission power control signal. If the transmission power control signal includes the main base station information and the main base station information does not indicate the base station information of the own station, The base station apparatus characterized by comprising a transmission power control means for the transmission power of descending the minimum transmission power. 24. A mobile station apparatus in a CDMA cellular mobile radio communication system which can be connected simultaneously with a soft handoff base station group composed of several stations among a plurality of base stations each broadcasting a unique pilot signal. Reception quality detection means for detecting the received call quality, a main base station detection means for detecting a main base station having a maximum reception level among received pilot signals from the soft handoff base station group, and the reception quality detection means If the detected call quality does not exceed the required quality, the power increase is set in the base station transmission power control information, and if the received call quality detected by the reception quality detecting means exceeds the required quality, the power decrease is transmitted to the base station. Base station transmission power control information determining means to be set in the power control information, determined by the base station control information determining means The base station transmission power control information is transmitted as a transmission power control signal to the soft handoff base station group, or the main base station information detected by the main base station detection means is periodically transmitted as the transmission power control signal to the soft handoff base station. A mobile station apparatus comprising: a control signal transmitting unit that transmits a control signal to a handoff base station. 25. A base station apparatus in a CDMA cellular mobile radio communication system which broadcasts a unique pilot signal and is capable of being connected to a mobile station as a soft handoff base station simultaneously with another soft handoff base station. Transmission power control signal detecting means for detecting a transmission power control signal from a station device, and when the transmission power control signal indicates the main base station information and the main base station information indicates the base station information of the own station. The transmission power after the current time is adjusted according to the transmission power control signal, and when the transmission power control signal indicates the main base station information and the main base station information does not indicate its own base station information, Transmission power control means for setting the transmission power of the base station to a minimum transmission power.