JP2004350329A - Receiving circuit of spread spectrum communication system and receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain a plurality of transmissions in parallel using a small scale circuit in relation to a spread spectrum communication apparatus, and especially with a spread spectrum communication apparatus which accesses a wireless circuit of a mobile communication system of a CDMA system. <P>SOLUTION: This spread spectrum communication apparatus which performs transmission by signal transmission diffused between the communication partners, and is used in the mobile communication system of a CDMA is constituted by comprising a first spreading codes generating means which generates a first spreading code which diffuses a voice signal, a second spreading code generating means which generates other codes than the first spreading code, i.e, the second spreading code which diffuses a non-voice signal, a first spreading treatment means which diffuses the voice signal in the first spreading code, a second spreading treatment means which diffuses the non-voice signal in the second spreading code, and a transmitting means to transmit a diffused voice signal and a diffused non-voice signal to the communication partners, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a spread spectrum communication apparatus mounted on a vehicle, a ship, an airplane, or other moving objects, or carried by a person, and more particularly to a spread spectrum communication apparatus that accesses a wireless channel of a CDMA mobile communication system.

2. Description of the Related Art Conventionally, in the field of mobile communication, various systems have been constructed in accordance with communication modes, communication contents, service targets, and other differences, and research and development on application of new technologies have been actively performed.
Among such techniques, the primary modulated wave signal generated by digitally modulating a carrier signal with transmission information is multiplied by a predetermined time-sequence spreading code to spread and transmit the frequency spectrum of the signal. The CDMA (Code Division Multiple Access) communication system, in which the primary modulated wave signal is restored by performing correlation detection using the same sequence of spreading codes as the received wave on the receiving side, is rich in secrecy, and the frequency in the wireless transmission path is high. In order to have characteristics that are not easily affected by selectivity fading and other fluctuations and interference / jam, and have compatibility as a random access communication system, application to mobile communication systems as a promising multiple access system has been studied. I have.
JP-A-55-38776 JP-A-63-14598

  By the way, since the mobile station of such a mobile communication system is configured to provide a voice call service, communication is performed via a facsimile terminal device or a data terminal in parallel with the call. However, in order to perform communication in parallel with the call in this way, a mobile station device connected to a terminal adapted to the content of the communication had to be separately used.

  An object of the present invention is to provide a spread spectrum communication apparatus capable of performing a plurality of communications in parallel using a small-scale circuit.

FIG. 1 is a principle block diagram of the present invention.
The present invention relates to an antenna sharing unit 11 for transmitting and receiving antennas, a modulating unit 12 ₁ , 12 ₂ for individually modulating a single carrier signal with transmission information, a steep autocorrelation characteristic, and a code sequence. the code generating means _131-134 which cross-correlation to produce a small spreading code individually, spread by the spreading code generated frequency spectrum of the modulated individual carrier signals by respective code generating means 13 _1, 13 ₂ The spreading processing means 14 ₁ and 14 ₂ for transmitting via the antenna sharing means 11 and the code generating means 13 ₃ and 13 ₄ for the phase of the spreading code component contained in the received wave obtained via the antenna sharing means 11 despreading processing with synchronization means 15 for synchronizing inversely spread by the spreading code generated frequency spectrum of the received wave by the code generating means 13 _3, 13 _4, respectively A stage 16 _1, 16 _2, despreading means 16 _1, 16 ₂ separately demodulate the despread received waves by a demodulation means 17 _1, 17 ₂ to recover the transmission information contained in these received waves It is characterized by having.

  The first spreading code generating means corresponds to the code generating means 131, the second spreading code generating means corresponds to the code generating means 132, the first spreading processing means corresponds to the spreading processing means 141, and the second spreading processing means corresponds to the coding means 142. , The first despreading processing means to the despreading processing means 161, the second despreading processing means to the despreading processing means 162, the transmission means to the antenna duplexer 11 or an antenna, and the reception means to the antenna duplexer 11. And antennas respectively.

(Action)
In the present invention, the modulation means 12 _1, the diffusion processing unit 14 _1, when already communicating path via the inverse diffusion processing unit 16 ₁ and the demodulation means 17 ₁ is formed, the diffusion processing unit 14 _2, the code generating means the 13 _2-generated spreading code, and modulation means 12 ₂ diffuses the frequency spectrum of a carrier signal modulated by the transmission information transmitted via the antenna sharing unit 11. Furthermore, the inverse diffusion processing section 16 _2, the spreading code code generator 13 ₄ outputs by component and the phase synchronization of the spread code of the received wave under the synchronous control of the synchronization means 15, inverse frequency spectrum of the received wave Spread. Demodulation means 17 ₂ restores transmission information this way demodulates the despread received wave. The first spreading code is generated by the first spreading code generating means, and the audio signal is spread by the first spreading processing means using the first spreading code. Also, a second spreading code is generated by a second spreading code generating means, and the second spreading code is used to spread a non-voice signal. By transmitting the spread voice signal and the spread non-voice signal to the base station by the transmitting means, both the voice signal and the non-voice signal can be simultaneously transmitted to the opposite radio station in parallel.

  Further, in another invention, the voice signal is spread by the first spreading processing means, and the non-voice signal is spread by the second spreading processing means using a spreading code different from the spreading code of the voice signal. Spread. By transmitting the spread voice signal and the spread non-voice signal by the transmission unit, both the voice signal and the non-voice signal can be simultaneously transmitted to the opposite radio station in parallel.

  In another invention, the voice signal is spread by the first spreading processing means, and the non-voice signal is spread by the second spreading processing means using a spreading code different from the spreading code of the voice signal. Spread. By transmitting the spread voice signal and the spread non-voice signal to different transmission destinations via the respective radio stations by the transmission means, the voice signal and the voice signal are transmitted to different non-voice signals. Can be transmitted simultaneously in parallel.

  In another invention, a spread voice signal and a spread non-voice signal are received by a receiving unit. The first spreading code generating means generates a first spreading code, and the first spreading code is used to despread the voice signal spread by the first despreading processing means. Further, the second spreading code is generated by the second spreading code generating means, and the non-voice signal spread by the second despreading processing means is despread by using the second spreading code. Both non-speech signals can be received simultaneously in parallel.

In another invention, a spread voice signal and a spread non-voice signal are received by a receiving unit. The spread voice signal is despread by the first despreading means, and the non-voice signal is despread by the second despreading means using a spreading code different from the spreading code of the voice signal. By spreading, both the voice signal and the non-voice signal can be received simultaneously in parallel.
According to another aspect of the present invention, the receiving unit receives the voice signal and the received signal transmitted from different transmission sources in a spread state through another wireless station. The spread voice signal is despread by the first despreading means, and the non-voice signal is despread by the second despreading means using a spreading code different from the spreading code of the voice signal. By spreading, both a voice signal and a non-voice signal from different sources can be received simultaneously and in parallel.

  As described above, in the present invention, the voice signal and the non-voice signal are spread with different codes, respectively, and are transmitted to the opposite radio station. Can be realized at the same time, and a wireless communication apparatus that can simultaneously transmit both voice signals and non-voice signals even when the destinations of the voice signals and the non-voice signals are different can be realized.

  Further, according to the present invention, since the speech signal and the non-speech signal spread from another radio station are received and despread with different codes, both the speech signal and the non-speech signal are simultaneously desired. And a wireless communication device that can receive both voice signals and non-voice signals at the same time, even when the sources of the voice signals and the non-voice signals are different from each other.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 2 is a diagram showing one embodiment of the present invention.
In the figure, the input / output on the terminal side of the control unit 21 is connected to a handset and to a facsimile terminal, a computer and other data terminals via a predetermined plug. The audio output of the control unit 21 is connected to one input of a multiplier 24 ₁ via an audio codec (CODEC) 22 _S and a modulator (MOD) 23 ₁ , and its output is a frequency converter 25 ₁ and a power amplifier 26 _1. To one input of the hybrid (H) 27. An output of the hybrid 27 is connected to a transmission input terminal of an antenna duplexer (DUP) 28, and the antenna terminal is connected to an antenna 29. One data output of the control unit 21 is directly connected to the connection point between the modulator 23 of the _input and output of the audio codec 22 _S. The other data output of the control unit 21 is connected to one input of the multiplier 24 ₂ via a modulator (MOD) 23 _2, its output via a frequency converter 25 ₂ and the power amplifier 26 ₂ hybrid 27 Is connected to the other input. The output of the oscillator 30 is connected to the carrier signal input of the modulators 23 ₁ and 23 ₂ , and the output of the oscillator 31 is connected to the local oscillation input of the frequency converters 25 ₁ and 25 ₂ . The transmission control output of the control unit 21 is connected to the control inputs of the power amplifiers 26 ₁ and 26 ₂ . The reception output terminal of the antenna duplexer 28 is connected to one input of the multipliers 34 ₁ and 34 ₂ via the reception unit 32 and the synchronization unit 33. The output of the multiplier 34 ₁ is connected to the detection input of the detection unit 35 _{1 and} the input of the synchronization control unit 36. The output of the detection unit 35 ₁ is connected to the input of one of the data input and the voice codec (CODEC) 22 _R of the control unit 21, the output of which is connected to the audio input of the control unit 21. The output of the multiplier 34 ₂ is connected to the detection input of the detection unit 35 _2, the output of which is connected to the other data input of the control unit 21. One output of the synchronization control unit 36 is connected to the synchronization input detection unit 35 _1, the other output of the synchronous control unit 36 is connected to the synchronization input detection unit 35 _2. The two channel setting outputs of the controller 21 are connected to the control inputs of the spreading pattern generators 37 ₁ and 37 ₂ , respectively. The output of the diffusion pattern generation unit 37 ₁ is connected to one feedback input of the multiplier 24 _1, 34 ₁ of the other input and the synchronization unit 33, the diffusion output of the pattern generation unit 37 ₂ of the multiplier 24 _2, 34 ₂ The other input and the other feedback input of the synchronization section 33 are connected. The two synchronization control outputs of the synchronization unit 33 are connected to the synchronization inputs of the spreading pattern generation units 37 ₁ and 37 ₂ , respectively.

  Note that the correspondence between the present embodiment and the block diagram shown in FIG. 1 is such that the hybrid 27 and the antenna sharing device 28 correspond to the antenna sharing device 11, the modulator 23 corresponds to the modulation device 12, and the spread pattern generation unit. 37 corresponds to the code generator 13, the multiplier 24, the frequency converter 25, the power amplifier 26 and the oscillator 31 correspond to the spreading processor 14, the receiver 32 and the synchronizer 33 correspond to the synchronizer 15, The detector 34 corresponds to the despreading unit 16, and the detection unit 35 and the synchronization unit 36 correspond to the demodulation unit 17.

FIG. 3 is a diagram illustrating a configuration example of a mobile communication system to which the present embodiment is applied.
In the figure, mobile stations 41 ₁ and 41 ₂ to which the present embodiment is applied are connected to a base station 42 via a CDMA communication wireless line, and the base station is connected to a public communication network. FIG. 4 is a diagram illustrating the operation of the present embodiment.
Hereinafter, the operation of this embodiment will be described with reference to FIGS.

Control unit 21 of the mobile station 41 ₁ instructs to generate a corresponding spreading pattern to the control for a radio channel based on pre-stored radio zone configuration in memory the spreading pattern generating unit 37 _1, the above-described A control radio channel controlled by the base station 42 is accessed via one data output and one data input.
In such access to a control radio channel, to generate a primary modulated wave signal by modulating the control information output modulator 23 ₁ a carrier signal output from the oscillator 30 from the controller 21. The multiplier 24 ₁ spreads the frequency spectrum of the signal by multiplying the primary modulated wave signal described above and a diffusion pattern which is output from the diffusion pattern generation unit 37 _1. Perform frequency conversion processing by multiplying the frequency converter 25 ₁ is the local oscillation signal output from the signal and the oscillator 31 output from the multipliers 24 ₁ in this way, the power amplifier 26 ₁ by such process The transmission wave obtained is amplified to a predetermined power and transmitted to the base station 42 via the hybrid 27, the antenna duplexer 28 and the antenna 29.

Further, the reception wave of the control wireless channel is provided to the reception unit 32 via the antenna 29 and the antenna duplexer 28. The receiving unit 32 controls the received wave under the control of an automatic gain control circuit (AGC) for correcting the level variation of the received wave and an automatic frequency control circuit (AFC) for matching the received band to the occupied bandwidth of the received wave. Is extracted. The synchronization unit 33 includes a synchronization acquisition circuit based on a predetermined method and a synchronization holding circuit (DLL) based on a delay lock tracking method. These circuits spread the components of the spreading pattern included in the reception wave extracted by the reception unit 32. The phase of the diffusion pattern output from the patterns 37 ₁ and 37 ₂ is synchronized, and the synchronization state is maintained. The multiplier 34 ₁ is based on the diffusion pattern output this manner from the diffusion pattern generation unit 37 ₁ performs inverse diffusion processing opposite to the multiplier 24 ₁ to the receiving wave.

In the synchronization control unit 36, the carrier recovery circuit (CR) performs predetermined signal processing on the signal obtained by such despreading processing to sufficiently suppress the modulated wave component, noise, and other unnecessary wave components. Generate a signal. Further, the clock recovery circuit (BTR) recovers a clock synchronized with the control information included in the received wave. Detection unit 35 ₁ detects the signal obtained by despreading processing described above on the basis of the such reference carrier signal and the clock, and restores the control information transmitted from the base station 42 gives the control unit 21 .

The control unit 21 performs a predetermined control operation according to the other and out area of its own station at the base station 42 and the opposing By accessing this way the control radio channel, for example, the mobile station 41 ₁ is sent In the process up to starting a call with the mobile station 41 ₂ , the control unit 21 of the mobile station 41 ₁ transmits a call signal indicating the destination mobile station 41 ₂ to the base station 42 according to an operation performed by the operator. (FIG. 4 (1)). The base station 42 performs predetermined call processing according to each information included in the call signal, and captures a free wireless channel for communication (FIG. 5 (1)) when setting a communication path. sending a channel designation signal indicating the identification information P ₁ of the spreading code corresponding to the channel to the mobile station 41 ₁ (Fig. 4 (2)).

In the mobile station 41 _1, the control unit 21 instructs to generate a spreading code corresponding to such identification information to the diffusion pattern generation unit 37 _1. That is, for the uplink audio signal given from the handset, the control unit 21, the audio codec 22 _S , the modulator 23 ₁ , the multiplier 24 ₁ , the frequency converter 25 ₁ , the power amplifier 26 ₁ , the hybrid 27, and the antenna duplexer 28 And a transmission path via the antenna 29 is formed, and the downlink audio signal transmitted from the base station 42 to the mobile station 41 ₁ is transmitted to the antenna 29, the antenna duplexer 28, the receiving unit 32, the synchronizing unit 33, and the multiplier 34 _1. Since a transmission path is formed via the detection unit 35 ₁ , the voice codec 22 _R, and the control unit 21, a communication radio channel connecting to the base station 42 is determined (FIG. 4C).

On the other hand, the base station 42 captures a communication channel (FIG. 5 (2)) in accordance with a predetermined call processing procedure in response to the outgoing call from the mobile station 41 ₁ and identifies the spreading pattern corresponding to the channel. P ₂ and transmits an incoming call signal indicating the identification number of the incoming call destination mobile station (FIG. 4 (3)). In the mobile station 41 ₂ , the control unit 21 accesses the control wireless channel in the same manner as the control unit 21 of the mobile station 41 ₁ , receives the above-mentioned incoming call signal, and analyzes the content of the signal to thereby control the mobile station 41 _2. Upon recognizing an incoming call to a station, spreading to generate the base station 42 transmits a call response signal (FIG. 4 (5)), and the spreading code corresponding to the identification information P ₂ included in the incoming call signal pattern commands the generator 37 _1.

In this way, the mobile station 41 ₂ establishes a communication radio channel connecting to the base station 42 (FIG. 4 (6)), and establishes a communication path with the mobile station 41 ₁ via the base station 42. It is formed. In the mobile stations 41 ₁ and 41 ₂ , the control unit 21 performs intermittent control of the output of the power amplifier 26 ₁ at a predetermined timing, thereby performing the transmission alternately with the base station 42 on the above-described communication radio channel. Communication is performed by the division duplex (TDD) method.

The base station 42 during a call, to recognize according to the reception electric field level of the call for a radio channel that the mobile station 41 ₁ is moved to a point to the closest distance to the own station, via the channel shift transmitting a power control command requesting to reduce transmit power to the station 41 _1. When the control unit 21 receives and recognizes such a command via the first data input, the mobile station 41 ₁ instructs the power amplifier 26 ₁ to reduce the output power. In this way, the power of the transmission wave fed from the power amplifier 26 ₁ to the antenna 29 side is reduced, and the base station 42 receives a large level of reception wave according to the movement of the mobile station 41 _1. This avoids the sensitivity suppression that occurs.

Further, as described above, the control unit 21 of the mobile station that starts a voice call makes the generation of the spreading pattern corresponding to the control wireless channel based on the configuration of the wireless zone stored in the memory in advance. instructs the pattern generator 37 _2, accesses the control radio channels controlled by the base station 42 via the other data output and the other data input as described above.

When such a control wireless channel is accessed, the same reference numeral with a suffix number of " ₂ " is used instead of each component with a suffix number " ₁ " as a reference number. , And the components indicated by reference numbers to which no additional numbers are assigned are used in combination. Therefore, the description of the basic operation of each unit is omitted here.
The control unit 21 performs a predetermined control operation according to a call that occurs in the own station during a call while facing the base station 42 by accessing the control wireless channel in this manner. If there is a facsimile incoming call with the mobile station 41 _{1 as the} destination, the base station 42 responds to the call by capturing an empty wireless communication channel (FIG. 5 (3)) and responding to the channel. transmitting the incoming call signal and the identification information P ₃ of the diffusion pattern showing the identification number of the incoming call destination mobile station (FIG. 4 (4)). When the control unit 21 of the mobile station 41 ₁ recognizes an incoming call to the own station by analyzing the identification number included in such an incoming call signal, it transmits an incoming call response signal to the base station 42 (see FIG. )), and since the command to generate a spreading code corresponding to the identification information P ₃ included in the incoming call signal to the diffusion pattern generation unit 37 _2, between the mobile station 41 ₁ and the public communication network, A communication path via the base station 42 is formed (FIG. 4 (6)).

In a state where such a communication path for incoming facsimile call during a call by voice is set in parallel, the control unit 21 transfers the signal given from the facsimile terminal to the modulator 23 _2, detection on the opposite portion 35 _The digital signal output from ₂ is given to the facsimile terminal. Further, the control unit 21, also in the second allocated call radio channel to a call in the same manner as in the first call for a radio channel assigned to the call, division duplex when intermittently the output of the power amplifier 26 ₂ A communication based on the communication (TDD) method is realized, and the output levels of the power amplifiers 26 ₁ and 26 ₂ are variably controlled in conjunction with a power control command received from the base station 42.

  As described above, according to the present embodiment, a modulator that performs primary modulation on a mobile station apparatus dedicated to voice communication, a multiplier that performs spreading processing, a spreading pattern generator, a frequency converter, a power amplifier, and a despreader A small-scale circuit is added like a multiplier that performs processing and a detector that restores the primary modulated wave signal, and an oscillator that determines the antenna system, the transmission / reception system of the wireless channel, the synchronization control system, and the transmission frequency. By sharing a circuit having a large circuit size or a circuit requiring a large mounting space, it is possible to form a communication path in parallel for a plurality of calls at the same time.

  That is, while satisfying the requirements for weight reduction and miniaturization originally required of the mobile station device, for example, voice communication and data communication using a facsimile terminal or other data terminals are performed in parallel, Since the data communication using the data terminals can be performed in parallel, the probability that an incomplete call will occur because the called mobile station is busy is reduced. Thus, data transmission to a desired destination can be performed using a facsimile terminal or the like without interrupting the call.

In the present embodiment, a case where a facsimile call is generated during a call is shown. However, the present invention is not limited to such a call. For example, an outgoing call or an incoming call related to a personal computer or other data terminal may be used. Even in the case where the call has occurred, the present invention can be applied in the same manner as long as the control unit 21 can perform call processing related to the call in parallel.
Further, in the present embodiment, the assignment of the communication radio channel to the mobile station is performed according to the spreading pattern specified by the base station according to a predetermined communication control procedure. However, the present invention is limited to such a scheme. However, for example, when the mobile station is assigned a plurality of spreading patterns in advance, and by appropriately selecting a vacant one of these spreading patterns, the mobile station accesses a wireless channel corresponding to the selected spreading pattern. The same can be applied to.

Further, in the present embodiment, although there is no regulation on the method of the modulation process performed by the modulators 23 ₁ and 23 ₂ , the present invention adds a small-scale circuit as described above, and Any method may be used as long as a parallel call state can be realized for a plurality of calls by sharing a circuit and a circuit requiring a large mounting space. Further, as for the spread spectrum method, if the original requirement for the mobile station apparatus is satisfied in the same manner, for example, a direct spread method, a frequency hopping method, a time hopping method, and a hybrid method based on a combination thereof can be applied. is there.

It is a principle block diagram of the present invention. It is a figure showing one example of the present invention. FIG. 1 is a diagram illustrating a configuration example of a mobile communication system to which an embodiment is applied. FIG. 4 is a diagram illustrating the operation of the present embodiment. FIG. 6 is a diagram illustrating the assignment of a diffusion pattern.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 11 Antenna sharing means 12 Modulation means 13 Code generation means 14 Spreading processing means 15 Synchronization means 16 Despreading processing means 17 Demodulation means 21 Control unit 22 Voice codec (CODEC)
23 Modulator (MOD)
24, 34 Multiplier 25 Frequency converter 26 Power amplifier 27 Hybrid (H)
28 Antenna duplexer (DUP)
29 Antenna 30, 31 Oscillator 32 Receiving unit 33 Synchronizing unit 35 Detecting unit 36 Synchronizing control unit 37 Spreading pattern generating unit 41 Mobile station 42 Base station

Claims (1)

In a spread spectrum communication apparatus used in a CDMA mobile communication system and performing communication by a communication signal spread with a communication partner,
First spreading code generating means for generating a first spreading code for spreading an audio signal;
A second spreading code generating means for generating a second spreading code which is a code different from the first spreading code and spreads a non-voice signal;
First spreading processing means for spreading the audio signal with the first spreading code;
Second spreading processing means for spreading the non-voice signal with the second spreading code;
A spread spectrum communication apparatus, comprising: a transmitting unit that transmits the spread voice signal and the spread non-voice signal to one communication partner.

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