JPH10126313A - Cdma mobile communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the reception quality by eliminating interference between other stations of an outgoing line with a small circuit scale in the mobile communication equipment using code division multiple access (CDMA). SOLUTION: A base station transmission section 100 is provided with a control channel spread means 101 that applies spread processing to various control data by using a number of channels making communication at present as an eliminated channel number, and a mobile station reception section 110 is provided with an interference channel inverse spread means 114 that generates an interference signal corresponding to the eliminated channel number sent from the base station, an interference signal generating means 115, and an interference eliminating demodulation means 116 that eliminates the interference component by subtracting each interference signal from a desired channel signal obtained by a desired channel inverse spread means 113. The base station selects a channel to be eliminated and informs it to the mobile station, so as to allow the mobile station to have only to eliminate interference from only selected specific channels only, then interference is eliminated with a small circuit scale.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication device using a CDMA (Code Division Multiple Access) system.

[0002]

2. Description of the Related Art In a mobile communication apparatus using a conventional CDMA system, there is a problem of interference between other stations in which signals of other stations in the same area interfere. CD that eliminates interference between other stations
Conventionally, as an MA mobile communication device, see Japanese Patent Application Laid-Open No. 7-9513.
No. 0 is known.

FIG. 6 shows a configuration of a receiver of a conventional CDMA mobile communication device of this type. In FIG. 6, reference numeral 1 denotes a wireless receiving unit that receives a received carrier signal and outputs a baseband received signal. Reference numeral 2 denotes a desired channel spreading unit that receives a received signal and outputs a desired channel signal. Reference numeral 3 denotes an interference channel despreading unit that receives a received signal and outputs an interference channel signal. Reference numeral 4 denotes a cancellation channel selection unit that receives an interference channel signal as input and outputs a cancellation channel number. Reference numeral 5 denotes an interference signal generation unit that receives the interference channel signal and the cancellation channel number as input and outputs the interference signal. Reference numeral 6 denotes an interference canceling / demodulating means for inputting a desired channel signal and an interference signal and outputting received data.

The operation of the CDMA mobile communication device configured as described above will be described. The wireless receiving unit 1 converts a signal of a carrier frequency received by an antenna into a baseband signal and outputs the baseband signal. Desired channel despreading means 2 despreads the received signal with a desired channel spreading code and outputs a desired channel signal. Interference channel despreading means 3 despreads the received signal with a spreading code assigned for another station and outputs an interference channel signal. The removal channel selection means 4
An interference channel signal that satisfies a specific condition is selected and its channel number is output. These specific conditions are:
This is a condition such as a large correlation with the desired channel signal. The interference signal generating means 5 generates and outputs an interference signal only from the selected interference channel. Interference removal / demodulation means 6
Subtracts an interference signal from a desired channel signal to remove interference, and performs detection and demodulation to output received data.

[0005]

However, in the above-mentioned conventional CDMA mobile communication apparatus, it is necessary to despread all the channels to check whether or not the interference component satisfies the condition. And the amount of calculation becomes large, and it is difficult to realize the method especially in a mobile station that requires miniaturization.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides an excellent CDMA mobile communication device capable of improving reception quality by eliminating interference between other stations even if the circuit scale and the amount of calculation are small. The purpose is to do.

[0007]

In order to achieve the above object, the present invention provides a base station transmitting unit which uses a control channel which spreads together with various types of control data with a channel number of a channel currently performing communication as a removal channel number. Spreading means, an interference channel despreading means and an interference signal generating means for generating an interference signal corresponding to the cancellation channel number transmitted from the base station in the mobile station receiving section, and subtracting each interference signal from the desired channel signal Thus, an interference removing means for removing an interference component is provided. As a result, even if the circuit scale and the amount of computation are small, it is possible to obtain an excellent CDMA mobile communication device that eliminates interference between other stations and improves reception quality.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a first aspect of the present invention, there is provided a communication system in which a base station transmitting section spreads a removal channel number together with various control data, and a communication which spreads communication data to be transmitted. A channel spreading unit, a multiplexing unit for multiplexing the control channel signal and the communication channel signal, and a radio transmitting unit for transmitting the multiplexed signal, wherein the mobile station receiving unit receives a signal from the base station Radio receiving means, control channel demodulation means for extracting a cancellation channel number together with various control signals, desired channel despreading means for extracting a desired channel signal, and interference channel despreading means for extracting an interference channel signal corresponding to the cancellation channel number. Signal generating means for generating an interference signal from an interference channel signal, and interference removing / demodulating means for demodulating received data by removing interference. CDMA mobile communication device provided with each mobile station, since each mobile station only needs to remove the interference signal of the channel of the number notified from the base station, interference can be efficiently removed even with a small circuit scale and the amount of computation, This has the effect that interference can be accurately removed even if the number of interfering stations changes.

According to a second aspect of the present invention, the base station transmitter includes a transmission power calculator for determining transmission power of a communication channel, and a cancellation channel selector for determining a cancellation channel number based on the transmission power. Control channel spreading means for spreading the removal channel number together with various control data,
Communication channel spreading means for spreading communication data to be transmitted, transmission power control means for outputting the spread communication data with the calculated transmission power, multiplexing means for multiplexing a control channel signal and a communication channel signal, A CDMA mobile communication device including a mobile station receiving unit including a mobile station receiving unit, wherein each mobile station has a high transmission power notified from the base station. It is possible to remove only the interference channel, effectively remove the interference with a small circuit scale and a small amount of computation, and even if the interference station changes dynamically due to a change in the transmission power to each mobile station, the interference that follows it It has the effect that it can be removed.

According to a third aspect of the present invention, the base station transmitter includes: a transmission power calculator for determining transmission power of a communication channel; a communication channel spreading unit for spreading communication data to be transmitted; Transmission power control means for outputting the communication data at the calculated transmission power, communication channel multiplexing means for multiplexing communication channel signals, and despreading the multiplexed communication channel signals to extract each communication channel signal Communication channel despreading means, interference signal canceling means for canceling interference of each communication channel, and S / S before and after interference cancellation.
S / I ratio calculation means for obtaining an I ratio (signal-to-interference ratio) and outputting an S / I ratio improvement amount, cancellation channel selection means for determining an cancellation channel number from the S / I ratio improvement amount, and various control data A mobile station, comprising: a control channel spreading means for spreading the multiplexed communication channel signal and the control channel signal; and a radio transmission means for transmitting the multiplexed signal. The receiving unit is a CDMA mobile communication device provided with a mobile station receiving unit. In each mobile station, only an interference channel having a large interference removing effect can be removed, and interference can be effectively removed with a small amount of circuit scale calculation. Even if the position or the like of the mobile station changes and the state of interference changes, interference can be removed following the change.

[0011] Further, according to a fourth aspect of the present invention, the mobile station receiving section includes a radio receiving means for receiving a signal from the base station;
Control channel demodulation means for extracting the removal channel numbers and desired channel numbers from a plurality of base stations together with various control signals and the amount of delay adjustment between the base stations, and communication for extracting communication channel signals corresponding to the removal channel numbers and the desired channel numbers Channel despreading means, an input of a desired channel number and a cancellation channel number, an interference signal generation means for generating an interference signal only for a channel to be canceled, and a delay amount between base stations to adjust the desired channel signal and the interference signal. A CDMA mobile communication device having an interference canceling / demodulating means for combining and demodulating received data, wherein the base station transmitting section is provided with the base station transmitting section, and can share a circuit for site diversity and interference canceling. Therefore, site diversity and interference cancellation can be performed with a small circuit scale, and the number of interference channels and base stations changes. Also has the effect that it is possible to adaptively interference alter the removal rate and the number of diversity branches, performs efficiently synthesized and interference cancellation.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 shows a configuration of a base station transmitting section and a mobile station receiving section of a CDMA mobile communication apparatus according to a first embodiment of the present invention. In the base station transmitting unit 100 of FIG. 1, reference numeral 101 denotes a control channel spreading unit that receives various control data and a removal channel number as input, and outputs a spread control channel signal. A communication channel spreading unit 102 receives each communication data as input and outputs a spread communication channel signal. 103 receives the spread control channel signal and communication channel signal as inputs,
A multiplexing unit that outputs a channel multiplexed signal. 1
Reference numeral 04 denotes a wireless transmission unit that receives a channel multiplexed signal and outputs a transmission carrier signal.

In the mobile station receiving section 110, 11
Reference numeral 1 denotes a wireless receiving unit that receives a received carrier signal and outputs a baseband received signal. Reference numeral 112 denotes a control channel demodulation unit that receives a received signal as input and outputs various control data and a removal channel number. Reference numeral 113 denotes a desired channel despreading unit that receives a received signal and outputs a desired channel signal. An interference channel despreading unit 114 receives the received signal and the cancellation channel number and outputs the interference channel signal. Reference numeral 115 denotes an interference signal generation unit that receives the interference channel signal and the cancellation channel number and outputs the interference signal. Reference numeral 116 denotes an interference canceling / demodulating means which receives a desired channel signal and an interference signal and outputs received data.

The operation of the CDMA mobile communication device configured as described above will be described below. First, the operation of base station transmitting section 100 will be described. The control channel spreading means 101 spreads, with the channel number of the communication channel which is currently performing communication, as the removal channel number, together with various control data, using a control channel spreading code.
In this way, by notifying the channel number currently being communicated from the base station, the mobile station only needs to remove the signal of the reported channel number, so that interference can be efficiently removed with a small circuit scale.

The communication channel spreading means 102 spreads communication data to each mobile station with a respective spreading code.
The multiplexer 103 multiplexes the spread control channel signal and the signal of each communication channel and outputs the multiplexed signal. Radio transmitting means 104 converts a multiplexed channel signal, which is a baseband signal, into a signal of a carrier frequency and outputs the signal from the antenna.

Next, the operation of mobile station receiving section 110 will be described. The wireless receiving means 111 converts the signal of the carrier frequency received by the antenna into a baseband signal and outputs it. The control channel demodulation unit 112 despreads the received signal with the spreading code of the control channel, detects and demodulates the same, extracts various control data, and extracts and outputs a removal channel number. Desired channel despreading means 113 despreads the received signal with a desired channel spreading code and outputs a desired channel signal.

The interference channel despreading means 114 calculates the spreading code of the channel to be removed from the removal channel number,
It is used to despread the received signal and output an interference channel signal. The interference signal generating means 115 multiplies a signal obtained by detecting and demodulating the interference channel signal by a code obtained as a product of the interference channel corresponding to the cancellation channel number and the spreading code of the desired channel. As a result, an interference signal of the interference channel component included in the output signal from desired channel despreading means 113 can be generated. This is obtained for all cancellation channels and output. The interference removing / demodulating means 116 removes the interference component by subtracting each interference signal from the desired channel signal, detects and demodulates it, and outputs it as received data.

As described above, according to Embodiment 1 of the present invention, control channel spreading means for spreading base station transmitting section 100 with the number of the channel currently performing communication as a removal channel number together with various control data. 101,
Interference channel despreading means 114 and interference signal generation means 115 for generating an interference signal corresponding to the cancellation channel number transmitted from the base station to mobile station receiving section 110, and a desired channel signal obtained by desired channel spreading means 113 Since the interference removal / demodulation means 116 for removing the interference component by subtracting each interference signal from the base station is provided, each mobile station only needs to remove the interference signal of the channel of the number notified from the base station. It is possible to efficiently remove interference with a small circuit scale and a small amount of calculation, and to accurately remove interference even if the number of interfering stations varies.

(Embodiment 2) FIG. 2 shows a second embodiment of the present invention.
2 shows a configuration of a base station transmitting unit of the CDMA mobile communication device according to the second embodiment, and the configuration of the mobile station receiving unit is the same as that of the mobile station receiving unit 110 according to the first embodiment shown in FIG. The configuration is the same as

In base station transmitting section 200 of FIG.
Reference numeral 1 denotes a transmission power calculation unit that receives mobile station reception power information and outputs transmission power of each communication channel. 202
Is a removal channel selecting means for inputting the transmission power of each communication channel and outputting the removal channel number. 203
Is a transmission power control means which receives the spread communication channel signal and the transmission power of each communication channel as inputs, and outputs the transmission power controlled communication channel signal as output. Other configurations are shown in FIG.
Since the configuration is the same as that of the first embodiment shown in FIG. 1, the same elements are denoted by the same reference numerals, and redundant description will be omitted.

The operation of the CDMA radio multiplex transmission apparatus configured as described above will be described below. In the base station transmitting section 200, the transmission power calculation means 201 performs transmission of each communication channel based on received power information such as received signal power received from the mobile station so that the received power of each mobile station is optimized. Determine and output power.

The communication channel signal having a large transmission power value becomes a large interference signal particularly for other mobile stations,
This is a factor that deteriorates the reception characteristics. Therefore, if these interference signals can be removed by the mobile station, the improvement of the reception characteristics is large. The cancellation channel selection unit 202 outputs a communication channel number that is considered to have a large interference cancellation effect based on the input transmission power of each communication channel. That is,
By using the transmission power of each communication channel at the base station to notify the mobile station of a channel having a high cancellation effect, efficient interference cancellation can be performed.

The obtained removal channel number is spread by the control channel spreading means 103 together with various control data. Transmission power control means 203 controls the transmission power of the communication channel signal spread by communication channel spreading means 104 according to the transmission power calculated by transmission power calculation means 201. The signal of each communication channel whose transmission power is controlled is multiplexed by the multiplexing means 103 together with the spread control channel signal, and converted into a carrier frequency signal by the radio transmitting means 104 and output.

As described above, according to Embodiment 2 of the present invention, base station transmitting section 200 selects and outputs a communication channel number having a high interference removal effect based on the transmission power of each communication channel. Channel selection means 202 is provided, and the mobile station receiving section 110 is provided with an interference channel despreading means for generating an interference signal corresponding to the cancellation channel number transmitted from the base station, an interference signal generation means, and a desired channel despreading means. Since the interference removal and demodulation means for removing the interference component by subtracting each interference signal from the desired channel signal is provided, each mobile station can remove only the interference channel with a large transmission power notified from the base station, Effectively eliminates interference with a small circuit scale and a small amount of computation.
Even if the interfering station changes dynamically due to a change in the transmission power to each mobile station, it is possible to remove interference following the change.

(Embodiment 3) FIG. 3 shows a third embodiment of the present invention.
A CDMA mobile communication apparatus according to the third embodiment corresponding to the first embodiment has a base station transmitting section, and the mobile station receiving section has the same configuration as the mobile station receiving section 1 according to the first embodiment shown in FIG.
This is the same as the configuration of FIG.

In base station transmitting section 300 of FIG.
1 receives a communication channel signal whose transmission power is controlled as an input,
Communication channel multiplexing means for outputting a communication channel multiplexed signal. Reference numeral 302 denotes a communication channel despreading unit that receives a communication channel multiplexed signal as input and outputs a demodulated communication channel signal. Reference numeral 303 denotes an interference signal removing unit that receives the demodulated communication channel signal as input and outputs the communication channel signal from which interference has been removed. Reference numeral 304 denotes an S / I ratio calculation unit that receives as input a communication channel signal whose transmission power is controlled, a demodulated communication channel signal, and a communication channel signal from which interference has been removed, and outputs an S / I ratio improvement amount. Reference numeral 305 denotes a removal channel selection unit that receives the S / I ratio improvement amount as input and outputs the removal channel number. A control channel multiplexing unit 306 receives the communication channel multiplexed signal and the spread control channel signal, and outputs the channel multiplexed signal. The other configuration is the same as the configuration in the second embodiment shown in FIG. 2, and therefore, the same elements are denoted by the same reference numerals and overlapping description will be omitted.

The operation of the CDMA mobile communication device configured as described above will be described below. First, the communication data to each mobile station is spread by the communication channel spreading means 102, and the transmission power is controlled by the transmission power control means 203 with the transmission power calculated by the transmission power calculation means 201 and output.

The communication channel multiplexing means 301 multiplexes signals of each communication channel whose transmission power is controlled and outputs the multiplexed signal. The communication channel despreading means 302 despreads the multiplexed communication channel signal with a spreading code corresponding to each channel, and outputs a demodulated communication channel signal.

The interference signal removing means 303 creates an interference signal based on the input demodulated communication channel signal, and subtracts it from the demodulated communication channel signal to remove interference. The obtained interference removal communication channel signal is output to the S / I ratio calculation means. The S / I ratio output unit 304 calculates an S / I ratio improvement amount by interference cancellation for each communication channel from the communication channel signal, the demodulated communication channel signal, and the interference removal communication channel signal. The obtained S / I ratio improvement amount is input to the cancellation channel selection means 305, and a communication channel number having a large interference cancellation effect is output. These actions are:
This is the same as the interference cancellation performed in each mobile station. That is, the interference removal of all mobile stations is performed in the base station, the correct interference removal effect is verified in the base station, and a communication channel number having a large interference removal effect is notified to the mobile station,
It is possible to efficiently remove interference at the mobile station.

Next, the operations of the interference signal elimination means 303, the S / I ratio output means 304 and the elimination channel selection means 305 will be described in detail with reference to FIG. First, the interference signal removing means 303 extracts communication data from all demodulated communication channel demodulated signals that have been input (step 40).
1). The operations from step 404 to step 408 are performed focusing on one desired channel i and one interference channel j corresponding thereto. If the number of channels is N, the interference channel for one desired channel is j
These operations are N × N−
This will be done once.

First, an interference signal of the j-th interference channel with respect to the i-th desired channel is created (step 404). This is the product of the spreading code of the desired channel and the interference channel,
It is obtained by multiplying the j-th demodulated data. By subtracting the obtained jth interference signal from the ith communication channel, j
An i-th communication channel signal from which the i-th interference channel signal has been removed is obtained (step 405). The determined interference removal communication channel is output to the signal S / I ratio calculation means 304 (step 406). The S / I ratio calculation means 304 calculates i
Received from the i-th communication channel signal and the i-th demodulation communication channel
/ I ratio and the S / I ratio after interference cancellation from the i-th communication channel signal and the i-th interference cancellation communication channel signal, and calculate the difference between them as the S / I ratio improvement amount by interference cancellation (step 407). The calculated S / I ratio improvement amount is cumulatively added for each channel (step 4).
08).

Steps 404 to 410 are repeated for all interference signals for the i-th communication channel (all N-1 communication channels where j ≠ i), thereby removing each interference signal for the i-th communication channel. The amount of improvement in the S / I ratio at that time is determined. Further, step 402 for all N communication channels.
By repeating Steps 412, when one communication channel becomes an interference channel with respect to another communication channel, the S / I ratio obtained by cumulatively adding the S / I ratio improved by interference cancellation to all communication channels The amount of improvement is required. In other words, the greater the obtained S / I ratio improvement amount is, the greater the effect is by removing the channel. The S / I ratio improvement amount is input to the cancellation channel selection means 205, and is compared with an appropriate threshold to select a communication channel having a large interference cancellation effect and output its channel number (step 413).
.

The obtained removal channel number is input to the control channel spreading means 101 of FIG. 3 together with various control data, spread with a control channel spreading code, and output as a control channel signal. The control channel multiplexing means 306 multiplexes the multiplexed communication channel signal and the control channel signal and outputs them. The channel multiplexed signal is converted into a signal of the carrier frequency by the radio transmission means 104 and output from the antenna.

As described above, according to Embodiment 3 of the present invention, base station transmitting section 300 includes interference signal canceling means 303 for canceling interference similar to each mobile station receiving apparatus, and interference canceling effect. S / I ratio calculation means 304 for obtaining the S / I ratio improvement amount, and cancellation channel selection means 305 for selecting a channel having a large cancellation effect from the obtained S / I ratio improvement amount are provided. Interference channel despreading means and interference signal generation means for generating an interference signal corresponding to the cancellation channel number transmitted from the base station, and subtracting each interference signal from the desired channel signal obtained by the desired channel despreading means Since the interference cancellation / demodulation means for removing the interference component is provided, each mobile station can remove only the interference channel having a large interference cancellation effect, and is effective with a small circuit scale operation amount. It is interference cancellation, the position or the like of the mobile station is interfering changes state changes, it is possible to make the interference cancellation that follows it.

(Embodiment 4) FIG. 5 shows a fourth embodiment of the present invention.
4 shows a configuration of a mobile station receiving unit of a CDMA radio multiplex transmission apparatus according to a fourth embodiment, and the configuration of a base station transmitting unit is the same as that of the base station transmitting unit 100 or the base station transmitting unit 100 shown in FIG. Same as 200 or 300.

In base station transmitting section 500 of FIG.
Reference numeral 1 denotes a wireless receiving unit that receives a received carrier signal and outputs a baseband received signal. Reference numeral 501 denotes a control channel demodulation unit that receives a received signal and outputs various control data, a desired channel number, a removed channel number, and a delay adjustment amount. Reference numeral 502 denotes a communication channel despreading unit that receives a received signal, a desired channel number, and a removal channel number and outputs each communication channel signal. Reference numeral 503 denotes an interference signal generation unit that receives a communication channel signal, a desired channel number, and a removal channel number as inputs and outputs a desired channel signal and an interference signal. Reference numeral 504 denotes an interference canceling / demodulating unit that receives a desired channel signal, an interference signal, and a delay adjustment amount and outputs received data.

The operation of the CDMA mobile communication apparatus configured as described above will be described below. The control channel demodulation unit 501 despreads the received signal received by the wireless reception unit 111 and converted into a baseband signal with a control channel spreading code, detects and demodulates the same, and extracts various control data. If this mobile station is close to the boundary with another base station area and is performing site diversity for receiving diversity from multiple base stations and performing diversity combining, control channels from all of the base stations are similarly demodulated. I do. At the same time, it extracts and outputs the desired channel number and interference channel number sent from each base station. Further, a time difference between base stations is extracted and output as a delay adjustment amount.

Communication channel despreading means 502 despreads the received signal using spreading codes corresponding to all of the input desired channel numbers and interference channel numbers, and outputs each communication channel signal. The interference signal generating means 503 determines whether each communication channel signal is a desired channel or an interference channel using the desired channel number and the interference channel number. Similarly to the above, the product of the interference channel and the desired channel spreading code is multiplied by the communication channel signal. By this operation, an interference signal of an interference channel component included in the desired channel signal can be generated.
In the case of the desired channel, the channel signal is output as it is. The interference canceling / demodulating means 504 adjusts the timing of the desired channel signal and the interference signal for each base station based on the input delay adjustment amount, adds the desired channel signal, and subtracts the desired channel signal for the interference channel. Then, interference removal and synthesis are performed, and detection and demodulation are performed to obtain received data.

As described above, according to Embodiment 4 of the present invention, mobile station receiving section 500 transmits a desired channel number, an interference channel number, and a delay adjustment amount between base stations from control channels transmitted from each base station. , A communication channel despreading unit 502 for extracting a communication channel signal corresponding to the removal channel number and the desired channel number, and a communication channel despreading unit 502 for extracting a communication channel signal corresponding to the desired channel number and the interference channel number. An interference signal generating unit 503 for determining whether the channel is a channel, and in the case of an interference channel, generating an interference signal for a desired channel signal;
The timing from each base station is adjusted, the desired channel is added, and the interference channel is subtracted. The interference canceling / demodulating means 504 for demodulating the combined signal is provided, so that the circuit for site diversity and interference canceling is shared. Therefore, site diversity and interference cancellation can be performed with a small circuit scale, and even if the number of interference channels or base stations fluctuates, the number of interference cancellations and diversity branches are adaptively changed to improve efficiency. Combination and interference cancellation can be performed well.

The present invention is realized by a program, which is recorded on a recording medium such as a ROM, a RAM floppy disk, an optical disk, an IC card or the like in which the program can be written, and transferred to a personal computer or the like. Can be.

[0041]

As described above, according to the present invention, the base station transmitting section is provided with control channel spreading means for spreading the number of the channel currently performing communication as a removal channel number together with various control data, and An interfering channel despreading means for generating an interfering signal corresponding to the cancellation channel number transmitted from the base station, an interfering signal generating means, and each interfering signal from the desired channel signal obtained by the desired channel despreading means. The interference cancellation / demodulation means that removes the interference component by subtracting the signal is provided. Therefore, it is possible to efficiently remove the interference even with a small circuit scale and the amount of calculation, and to accurately remove the interference even if the number of interfering stations fluctuates. An excellent CDMA mobile communication device is obtained.

Further, according to the present invention, the base station transmitting section includes:
A cancellation channel selection means for selecting and outputting a communication channel number having a high interference cancellation effect based on the transmission power of each communication channel is provided, and an interference signal corresponding to the cancellation channel number transmitted from the base station is provided in the mobile station receiving unit. An interference channel despreading means and an interference signal generation means, and an interference canceling / eliminating means for removing an interference component by subtracting each interference signal from a desired channel signal obtained by the desired channel despreading means.
Since the demodulation means is provided, each mobile station can remove only an interference channel with a large transmission power notified from the base station, can effectively remove interference with a small circuit scale and a small amount of calculation, and Even if the interference station changes dynamically due to a change in the transmission power, an excellent CDMA mobile communication device capable of removing interference following the change can be obtained.

Further, according to the present invention, an interference signal canceling means for canceling interference in a base station transmitting apparatus similar to that of a mobile station receiving apparatus, and an S / I for obtaining an interference canceling effect as an S / I ratio improvement amount. A ratio calculating unit, and a cancellation channel selection unit for selecting a channel having a large cancellation effect from the obtained S / I ratio improvement amount, wherein an interference signal corresponding to the cancellation channel number transmitted from the base station is provided to the mobile station receiving unit. And the interference channel despreading means and the interference signal generating means for generating the interference signal and the interference canceling / demodulating means for removing the interference component by subtracting each interference signal from the desired channel signal obtained by the desired channel despreading means. In each mobile station, it is possible to remove only an interference channel having a large interference removal effect, effectively remove interference with a small amount of circuit scale calculation, and change the position of the mobile station. Even Wataru state changes, excellent CDMA mobile communication device capable of interference cancellation which follows thereto is obtained.

Further, according to the present invention, the mobile station receiving section includes:
Control channel demodulation means for extracting a desired channel number, an interference channel number, and a delay adjustment amount between base stations from control channels transmitted from each base station, and communication for extracting a communication channel signal corresponding to the removal channel number and the desired channel number Channel despreading means, an interference signal generating means for determining whether each receiving channel is a desired channel or an interference channel from a desired channel number and an interference channel number, and generating an interference signal for the desired channel signal in the case of an interference channel; Adjustment of the timing from the base station, addition of the desired channel, and subtraction of the interference channel provide interference cancellation / demodulation means for demodulating the combined signal, so that the circuit for site diversity and interference cancellation can be shared. Therefore, site diversity and interference cancellation can be performed with a small circuit size. An excellent CDMA mobile communication device capable of efficiently performing combining and interference cancellation by adaptively changing the number of interference cancellations and the number of diversity branches even if the number of interference channels and the number of base stations fluctuate. Is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram of a CDMA mobile communication device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a CDMA mobile communication device according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a CDMA mobile communication device according to a third embodiment of the present invention.

FIG. 4 is a flowchart for explaining an operation of selecting a removal channel of a CDMA mobile communication device according to Embodiment 3 of the present invention;

FIG. 5 is a block diagram of a mobile station receiving unit of a CDMA mobile communication device according to Embodiment 4 of the present invention.

FIG. 6 is a block diagram of a receiving unit of a conventional CDMA mobile communication device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 radio receiving means 2 desired channel despreading means 3 interference channel despreading means 4 cancellation channel selection means 5 interference signal generation means 6 interference cancellation / demodulation means 100 base station transmitter 101 control channel spreading means 102 communication channel spreading means 103 multiplexing Means 104 Radio transmitting means 110 Mobile station receiving section 111 Radio receiving means 112 Control channel demodulating means 113 Desired channel despreading means 114 Interference channel despreading means 115 Interference signal generating means 116 Interference removing / demodulating means 200 Base station transmitting section 201 Transmission power Calculation means 202 Elimination channel selection means 203 Transmission power control means 300 Base station transmission part 301 Communication channel multiplexing means 302 Communication channel despreading means 303 Interference signal elimination means 304 S / I ratio calculation means 305 Elimination channel selection means 306 Control channel multiplexing unit 500 mobile station receiver 501 control channel demodulating unit 502 interference channel despreading unit 503 the interference signal generating unit 504 interference removal and demodulation means

Claims (4)

[Claims] 1. A base station transmitting unit, comprising: a control channel spreading unit for spreading a removal channel number together with various control data; a communication channel spreading unit for spreading communication data to be transmitted; and a control channel signal and a communication channel signal. Multiplexing means for transmitting a multiplexed signal, and a radio transmitting means for transmitting a multiplexed signal, wherein the mobile station receiving section extracts a removal channel number together with a radio receiving means for receiving a signal from a base station and various control signals. Control channel demodulation means, desired channel despreading means for extracting a desired channel signal, interference channel despreading means for extracting an interference channel signal corresponding to the cancellation channel number, and interference signal generation means for generating an interference signal from the interference channel signal. A CDMA mobile communication device comprising: an interference canceller / demodulator for demodulating received data by eliminating interference. 2. A transmission power calculation means for determining transmission power of a communication channel, a removal channel selection means for determining a removal channel number based on the transmission power,
Control channel spreading means for spreading the removal channel number together with various control data, communication channel spreading means for spreading communication data to be transmitted, transmission power control means for outputting spread communication data with the calculated transmission power, 2. A CDMA comprising a multiplexing means for multiplexing a control channel signal and a communication channel signal, and a radio transmitting means for transmitting a multiplexed signal, wherein the mobile station receiving section comprises the mobile station receiving section according to claim 1. Mobile communication device. 3. A transmission power calculating means for determining a transmission power of a communication channel, a communication channel spreading means for spreading communication data to be transmitted, and a transmission power calculated on the spread communication data. A communication channel multiplexing means for multiplexing communication channel signals; a communication channel despreading means for despreading the multiplexed communication channel signals to extract each communication channel signal; Interference signal canceling means for canceling interference of the channel, S / I ratio calculating means for obtaining an S / I ratio (signal-to-interference ratio) before and after interference cancellation and outputting an S / I ratio improvement amount;
Removal channel selection means for determining a removal channel number from the ratio improvement amount, control channel spreading means for spreading various control data and the removal channel number, and control channel multiplexing means for multiplexing multiplexed communication channel signals and control channel signals. 2. A CDMA mobile communication apparatus comprising: a mobile station receiving unit according to claim 1; and a wireless transmitting unit that transmits a multiplexed signal. 4. A mobile station receiving section comprising: a radio receiving means for receiving a signal from a base station; and various control signals together with a removal channel number from a plurality of base stations, a desired channel number, and a delay adjustment amount between the base stations. Control channel demodulation means for extracting,
Communication channel despreading means for extracting a communication channel signal corresponding to a cancellation channel number and a desired channel number; interference signal generation means for receiving the desired channel number and the cancellation channel number and generating an interference signal only for the channel to be canceled; 3. A base station transmitting unit, comprising: an interference canceling / demodulating means for adjusting a delay amount between stations to synthesize a desired channel signal and an interference signal and demodulate received data.
Or CDMA provided with the base station transmitting unit according to claim 3.
Mobile communication device.