JPH1041852A - Receiving device for spread spectrum communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the small and inexpensive receiving device for spread spectrum communication, by sharing a signal generator to be the cause of circuit scale increase. SOLUTION: Spectrum spreading is executed, and also a signal converted into a frequency area being higher than its signal frequency band is received in the receiving device. The device is so constituted as to share the signal generator 13 for generating the signal to execute frequency conversion from a reception signal band to a baseband signal and the signal generator 13 for generating the signal to supply a reception signal to inverse spreading equipments 21 and 22, in order to execute inverse spectrum spreading. Thus, the device scale for the receiving device is made small just by this portion, so that the small and inexpensive receiving device for spread spectrum communication is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a receiver for spread spectrum communication.

[0002]

2. Description of the Related Art A conventional spread spectrum communication receiving apparatus will be described with reference to FIG. In FIG. 6, 10
Is an antenna, 101 is a frequency converter, 102 is a signal generator, 201 is a despreader, 23 is a despread synchronization error detector,
24 is a clock generator, 25 is a spreading code generator, 30
1, 302 is a frequency converter, 303 is a 90 degree phase shifter, 3
04 is a signal generator, 15 is a synchronization error detector, and 31 is a data demodulator.

[0003] A signal that has been spread spectrum and converted to a higher frequency band than the signal frequency band is received by an antenna 10, and a lower frequency signal is generated by a frequency converter 101 based on a signal generated by a signal generator 102. The frequency is converted into a band, and the spectrum is despread by the despreader 201 using the despreading spreading code generated by the spreading code generator 25, and the signal before spectrum spreading is reproduced on the transmission side.

After that, the reproduced signal before spectrum spreading on the transmission side is converted into frequency converters 301, 302, 9
A detector constituted by a 0-degree phase shifter 303 and a signal generator 304 detects a received signal and outputs a data demodulator 31.
To restore the transmitted signal. Further, in order to synchronize the output signals of the signal generator 304 and the outputs of the frequency converters 301 and 302 of the received signals with the received signals after spectrum despreading inputted to the frequency converters 301 and 302, the frequency converters are used. Based on the outputs of the synchronization error detectors 301 and 302,
Detects the synchronization error and adjusts the phase of the signal generator 304.

[0005] As described above, in the conventional spread-spectrum communication receiving apparatus, the frequency of the received signal is once converted, the spectrum is despread, the synchronous detection is performed, and the received data is obtained. I have.

However, in the conventional spread spectrum communication receiving apparatus, the number of signal generators which greatly contribute to downsizing of the receiving apparatus is reduced by reducing the number of signal generators in an ordinary receiving apparatus which does not perform the spread spectrum method. Even if the direct detection method used to reduce the size of the device is directly employed, there is a disadvantage that the size of the receiving device cannot be reduced.

That is, in a conventional receiver for spread spectrum communication, a received signal is once subjected to frequency conversion, then subjected to spectrum despreading processing, and then subjected to synchronous detection to obtain received data. The frequency conversion of the received signal is performed twice, once before spectrum despreading and once again in the process of synchronous detection after spectrum despreading. For this reason, even if the direct detection method is used as it is, the spectrum is despread after the frequency conversion, and then the synchronous detection is performed.

For this reason, even if the frequency converter 101 directly converts the frequency to a baseband signal, the received signal has already been converted to a baseband signal after the spectrum despreading process is performed by the despreader 201. Although the synchronous detection is performed only from the quasi-synchronous state, the synchronous detector including the frequency converters 301 and 302, the 90-degree phase shifter 303, and the generator 304 is required. for that reason,
The number of signal generators that greatly contributes to downsizing of the receiving device cannot be reduced, and even if the direct detection method is adopted, it cannot contribute to reduction of the device size.

[0009]

As described above, in the conventional spread-spectrum communication receiver, the number of signal generators is reduced by reducing the number of signal generators in an ordinary receiver that does not use the spread-spectrum system. However, even if the direct detection method can be used, the number of signal generators cannot be reduced, so that the size of the device cannot be reduced. Was.

An object of the present invention is to realize a small and inexpensive spread spectrum communication receiving apparatus.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a receiver for spread spectrum communication according to the present invention receives a signal that has been spread spectrum and converted to a high frequency band, Based on the reference signal generated by the signal generator, the signal is frequency-converted into the frequency band of the original signal, the signal is restored by spectrum despreading, and the signal generation is performed based on the phase information extracted from the restored signal. By controlling the frequency of the reference signal generated by the signal generator by controlling the signal generator, the phase of the restored signal is controlled so as not to change.

By the above means, a signal generator for generating a reference signal for performing frequency conversion from a reception signal band and a signal generator for generating a reference signal for synchronous detection can be shared. Therefore, the number of signal generators that cause an increase in the size of the receiving device can be reduced, so that the device size of the receiving device can be reduced accordingly, and a small and inexpensive receiving device can be realized.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram for explaining a first embodiment of the present invention. In FIG. 1, 10 is an antenna, 11,
12 is a frequency converter, 13 is a signal generator, 14 is a 90-degree phase shifter, 15 is a synchronization error detector, 21 and 22 are despreaders, 23 is a despread synchronization error detector, 24 is a clock generator, 25 Is a spread code generator, and 31 is a data demodulator. The frequency converters 11 and 12 and the signal generator 1
3, a 90-degree phase shifter 14 and a synchronization error detector 15 include a despreader 21, 22, a despread synchronization error detector 23, a clock generator 24, and a spreading code generator 25 in a synchronous detection loop. It has a configuration including a spectrum despreading loop.

The operation of FIG. 1 will be described. A signal that is spread spectrum and converted to a frequency band higher than the signal frequency band is received by the antenna 10, the signal generated by the signal generator 13, and the phase of the signal are shifted by 90 degrees by the phase shifter 14. Based on the shifted ones, the frequency converters 11 and 12 convert the signals into frequencies of baseband signal bands, respectively, and use the spreading code for despreading generated by the spreading code generator 25 to perform despreading, respectively. Vessel 21,
At 22, spectrum despreading is performed to obtain a signal. In order to synchronize with the received signals input to the frequency converters 11 and 12, a synchronization error is detected by a synchronization error detector 15 based on the outputs of the despreaders 21 and 22, and the phase of the signal generator 13 is changed. Adjustments are made.

With this configuration, since the received data after synchronous detection is obtained at the outputs of the despreaders 21 and 22, it is possible to restore the signal transmitted on the transmission side by the data demodulator 31 and obtain it as a data output. it can.

Next, the operation of FIG. 1 will be further described with reference to FIG. 2 showing signal spectra of respective parts (a) to (e) of FIG.

FIG. 2A shows a signal received by the antenna 10.
This is a signal spectrum that has been spread spectrum and has been converted to a frequency range higher than the signal frequency band. This received signal has a spectrum spread around the carrier wave frequency fo. FIG. 2 (b)
The frequency f generated by the signal generator 13 is the same as that of the carrier.
3 is the spectrum of the signal o. FIG. 2C shows a received signal that has been subjected to spectrum spreading after frequency conversion to baseband. FIG. 2D shows the spread code generator 2.
5 is a spectrum of a spreading code for despreading generated in FIG. FIG. 2E shows a spread-spectrum received signal after frequency conversion to a baseband whose spectrum is shown in FIG. 2C by a spreading code generator 25 whose spectrum is shown in FIG. 2D. It is a signal spectrum after despreading is performed by despreaders 21 and 22 using the generated spreading code for despreading.

As shown in FIG. 2, according to this embodiment, a reliable spread spectrum is performed, and a received signal converted into a frequency band higher than the signal frequency band is converted into a despread baseband signal. Is obtained correctly.

In this embodiment, in a normal receiving apparatus that does not use the spread spectrum method, as in the case where the direct detection method is employed, frequency conversion from a received signal band to a baseband signal can be performed simultaneously with synchronization processing. A signal generator that generates a signal serving as a reference for performing frequency conversion from a signal band to a baseband signal and a signal generator that generates a reference signal for synchronous detection can be combined. Therefore, it is possible to reduce the number of signal generators that cause an increase in the scale of the apparatus, and to reduce the number of signal generators that cause an increase in the scale of the apparatus. A small and inexpensive spread spectrum communication receiving apparatus can be realized.

FIG. 3 is a block diagram for explaining a second embodiment of the present invention. Note that components having the same functions as those in FIG. 1 are denoted by the same reference numerals. FIG.
, 10 is an antenna, 11 and 12 are frequency converters, 13 is a signal generator, 14 is a 90-degree phase shifter, 15 is a synchronization error detector, 21 and 22 are despreaders, and 23 is a despread synchronization error detector. , 24 are a clock generator, 25 is a spreading code generator, and 31 is a data demodulator. Then, the frequency converters 11 and 12, the signal generator 13, the 90-degree phase shifter 14,
In the synchronous detection loop constituted by the synchronous error detector 15, despreaders 21 and 22, a despread synchronous error detector 23,
The configuration is such that a loop for spectrum despreading consisting of a clock generator 24 and a spreading code generator 25 is included.

A signal that is spread spectrum and converted to a frequency band higher than the signal frequency band is received from the antenna 10 and generated by the signal generator 13;
The frequency converters 11 and 12 frequency-convert the signals into baseband signal bands based on the signals whose phases are shifted by 90 degrees by the 90-degree phase shifter 14, respectively. Using the spreading code for despreading generated by the spreading code generator 25,
Spectrum despreading is performed by despreaders 21 and 22, respectively. In order to synchronize with the reception signals input to the frequency converters 11 and 12, the outputs of the despreaders 21 and 22 are input to a synchronization error detector 15, where a synchronization error is detected, and this is used as a control signal. The signal is supplied to the signal generator 13 to adjust the phase.

As described above, the despreaders 21 and 22 are used.
Since the received data after synchronous detection is obtained at the output of
The signal transmitted on the transmission side can be restored by the data demodulator 31 and obtained as a data output.

In general, in spread-spectrum communication, the I-axis and Q-axis of a transmission carrier are almost always spread with the same type and the same phase spread code generated from one spread code generator. . In this case, the I-axis and Q
It is self-evident that the synchronization error of axis despreading is always the same. Accordingly, in this case, the despread synchronization error detector 23 for performing despread synchronization tracking in the receiver for spread spectrum communication is provided by the despreaders 2 on the I-axis side and the Q-axis side.
It is not necessary to rely on both outputs 1 and 22, it is sufficient to rely on one of the outputs.

Therefore, it is assumed that a spread spectrum communication in which the I axis and the Q axis of the transmission wave are spread by the same type and the same phase spread code generated from one spread code generator is received. Out of the outputs of the two despreaders 21 and 22 corresponding to the I-axis and the Q-axis, only the output of one of the despreaders 22 is input to the despreading synchronization error detector 23 to perform despreading synchronization tracking. The configuration of the despread synchronization error detector 23 can be simplified by the reduced number of inputs as compared with the case of the spread spectrum communication receiver according to the present invention shown in FIG.

As described above, in the embodiment shown in FIG. 3, as in the case where the direct detection system is employed in the ordinary receiving apparatus which does not perform the spread spectrum system, the frequency conversion from the received signal band to the baseband signal and the synchronization processing are performed at the same time. Therefore, a signal generator that generates a reference signal for performing frequency conversion from a received signal band to a baseband signal and a signal generator that generates a reference signal for synchronous detection can be combined. Therefore, it is possible to reduce the number of signal generators that cause an increase in the scale of the device, and to reduce the number of signal generators that are the source of the increase in the scale of the device. A small and inexpensive spread spectrum communication receiving apparatus can be realized.

The block shown in FIG. 4 is a third embodiment of the present invention.
This is for describing the embodiment. In spread spectrum communication, in order to increase the secrecy of the communication, different types of spreading codes may be used on the I axis and the Q axis of the transmission carrier, and the receiving device of the spread spectrum communication according to this embodiment corresponds to this. It was done. Note that components having the same functions as those of this embodiment and the embodiment shown in FIG. 1 will be described with the same reference numerals.

In FIG. 4, reference numeral 10 denotes an antenna;
2 is a frequency converter, 13 is a signal generator, 14 is a 90-degree phase shifter, 15 is a synchronization error detector, 21 and 22 are despreaders,
23 is a despread synchronization error detector, 24 is a clock generator,
25 and 26 are spreading code generators, 27 is phase synchronization means, 3
1 is a data demodulator. Then, the frequency converter 11,
12, a signal generator 13, a 90-degree phase shifter 14, and a synchronization error detector 15, a despreader 21, 22, a despread synchronization error detector 23, a clock generator 24, Code generators 25 and 26, phase synchronization means 27
It is configured to include a loop of spectrum despreading consisting of

In the receiving apparatus according to this embodiment, a signal that has been spread spectrum and converted to a frequency band higher than the signal frequency band is received by the antenna 10.
The signal generated by the signal generator 13 and the signal
Based on the signal whose phase is shifted by 90 degrees by the 0-degree phase shifter 14, the frequency is converted to a baseband signal band using the frequency converters 11 and 12, respectively. Spreading code generator 2
The despreaders 21 and 22 perform spectrum despreading using the spreading codes for despreading generated at 5 and 26, respectively. At this time, under the control of the phase synchronization means 27, the phase difference between the despreading spreading codes generated by the spreading code generators 25 and 26 is fixed to a predetermined value. In order to synchronize with the received signals input to the frequency converters 11 and 12, a synchronization error is detected by a synchronization error detector 15 based on the outputs of the despreaders 21 and 22, and the phase of the signal generator 13 is changed. Adjustments are made.

According to this configuration, since the received data after the synchronous detection is obtained at the outputs of the despreaders 21 and 22, the signal transmitted on the transmission side can be restored by the data demodulator 31 and obtained as a data output. it can.

In order to increase the confidentiality of communication in spread spectrum communication, even if different types of spreading codes are used on the I axis and the Q axis of the transmission carrier, the two spreading codes have the same chip speed and cycle. For example, it is obvious that the synchronization error of the despreading of the I-axis and the Q-axis of the received wave always becomes the same in the synchronization tracking of the despreading necessary for the despreading process at the time of reception. Therefore, in that case, the despread synchronization error detector 23 for performing the despread synchronization tracking in the receiver of the spread spectrum communication is:
It is not necessary to base the outputs of both the de-spreaders 21 and 22 on the I-axis side and the Q-axis side, but it is sufficient to base the output on either one.

Therefore, assuming that the spread spectrum communication in which the I-axis and the Q-axis of the transmission wave are spread using different types of spreading codes having the same chip speed and cycle is received, FIG. As in the spread spectrum communication receiver according to the present invention, only the output of one of the despreaders 22 and 22 corresponding to the I-axis and the Q-axis is used to detect the despread synchronization error. Input to the demultiplexer 23 to perform despreading synchronous tracking.

The phase relationship between the two types of spreading codes used for despreading on the I-axis side and the Q-axis side is such that the spreading code generators 25 and 26 are phase-synchronized so as to match the parameters of the spreading code on the transmitting side. In order to increase the secrecy of communication by controlling by means 27, even in the case of spread spectrum communication using different types of spread codes on the I-axis and Q-axis of the transmission carrier, the chip speed of these two spread codes and If the period is the same, the receiver can be realized only by adding the spread code generator and the phase synchronization means of the spread code.

Of course, also in this embodiment, similar to the case where the direct detection system is employed in the ordinary receiving apparatus which does not perform the spread spectrum system, the synchronous processing can be performed simultaneously with the frequency conversion from the received signal band to the baseband signal. A signal generator that generates a reference signal for performing frequency conversion from a received signal band to a baseband signal and a signal generator that generates a reference signal for synchronous detection can be combined. Therefore, it is possible to reduce the number of signal generators that may cause an increase in the scale of the apparatus, to reduce the scale of the apparatus of the receiving apparatus, and to realize a small and inexpensive spread spectrum communication receiving apparatus.

A fourth embodiment of the spread spectrum communication receiving apparatus according to the present invention will be described with reference to the block diagram of FIG. In spread-spectrum communication, different types of spreading codes may be used on the I-axis and the Q-axis of a transmission carrier in order to increase the secrecy of the communication. In particular, in order to increase confidentiality, the types of spreading codes spread on the I-axis and the Q-axis are different, and the chip speed and the code length may be different. However, reception of spread spectrum communication according to this embodiment is shown. The device corresponds to this.

In the drawing, components having the same functions as those in FIG. 1 will be described with the same reference numerals. In FIG. 5, 10
Is an antenna, 11 and 12 are frequency converters, 13 is a signal generator, 14 is a 90-degree phase shifter, 15 is a synchronization error detector, 2
Reference numerals 1 and 22 are despreaders, 23 and 28 are despread synchronization error detectors, 24 and 29 are clock generators, 25 and 26 are spreading code generators, and 31 is a data demodulator.

The despreaders 21 and 22 are placed in a synchronous detection loop composed of the frequency converters 11 and 12, the signal generator 13, the 90-degree phase shifter 14, and the synchronous error detector 15.
Despread synchronization error detectors 23 and 28, clock generator 2
4, 29, and a spread code generator 25, 26 and a loop for spectrum despreading.

Also in this embodiment, a signal that has been spread spectrum and converted to a frequency band higher than the signal frequency band is received by the antenna 10 and transmitted to the signal generator 13.
, And the 90-degree phase shifter 14
Frequency converter 1 based on the phase shifted by 90 degrees
At 1 and 12, the frequency is converted to a baseband signal band, and the despreaders 21 and 22 perform spectrum despreading using the despreading spread codes generated at the spread code generators 25 and 26, respectively.

In order to synchronize with the received signals inputted to the frequency converters 11 and 12, a synchronization error is detected by a synchronization error detector 15 based on the outputs of the despreaders 21 and 22, and a signal generator 13 Is adjusted. With this configuration, since the received data after the synchronous detection is obtained at the outputs of the despreaders 21 and 22, the signal transmitted on the transmitting side by the data demodulator 31 can be restored and obtained as a data output.

In order to increase the secrecy of communication in spread spectrum communication, different types of spreading codes are used on the I axis and the Q axis of the transmission carrier, and the types of spreading codes spread on the I axis and the Q axis are different. In addition, when the chip speed and the code length are different, in the despreading synchronous tracking required in the despreading process at the time of reception, it is necessary to perform the despreading process completely independently on the I-axis side and the Q-axis side of the received wave. .

In the receiver for spread spectrum communication according to the present invention shown in FIG. 5, the despreading process is performed independently on the I-axis side and the Q-axis side. Device 24, spreading code generator 25
And a synchronous tracking loop thereof, and a despreader 22, a despread synchronization error detector 28, a clock generator 29, and a spread code generator 26. In order to increase the secrecy of communication in spread spectrum communication, different types of spreading codes are used on the I axis and the Q axis of the transmission carrier,
In addition to the different types of spreading codes spread on the axis and the Q axis,
Even if the chip speed and the code length are different, the receiver can be realized.

Of course, the receiving apparatus for spread spectrum communication according to the present invention shown in FIG. 5 also converts the received signal band to the baseband signal in the same manner as in the case where the direct detection method is employed in a normal receiving apparatus which does not perform the spread spectrum method. Synchronization can be performed simultaneously with frequency conversion, so a signal generator that generates a reference signal for performing frequency conversion from a received signal band to a baseband signal and a signal generator that generates a reference signal for synchronous detection can be combined. it can.

As a result, the number of signal generators on which the apparatus scale can be increased can be reduced, and the number of signal generators on which the apparatus scale can be increased can be reduced. Accordingly, a small and inexpensive spread spectrum communication receiving apparatus can be realized.

[0043]

As described above, according to the receiver for spread spectrum communication of the present invention, a signal generator for generating a reference signal for performing frequency conversion from a received signal band to a baseband signal, and a synchronous detector. Since the signal generator for generating the reference signal can be shared, the number of signal generators, which is the basis for increasing the device scale, can be reduced, and the device scale of the receiving device can be reduced accordingly.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining a first embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining a signal spectrum of each main part in FIG. 1;

FIG. 3 is a block diagram for explaining a second embodiment of the present invention.

FIG. 4 is a block diagram for explaining a third embodiment of the present invention.

FIG. 5 is a block diagram for explaining a fifth embodiment of the present invention.

FIG. 6 is a block diagram for explaining a conventional spread spectrum communication receiving apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Antenna, 11, 12 ... Frequency converter, 13 ... Signal generator, 14 ... 90 degree phase shifter, 15 ... Synchronization error detector, 21, 22 ... Despreader, 23, 28 ... Despread synchronization error detector , 24, 29 ... clock generators, 25, 26 ...
Spreading code generator, 27: phase synchronization means, 31: data demodulator.

Claims (8)

[Claims] 1. A signal which is spread spectrum and converted into a high frequency band is received, and the received signal is frequency-converted into a frequency band of an original signal based on a reference signal generated by a signal generator. Restoring the signal by spectrum despreading, controlling the signal generator based on the phase information extracted from the restored signal, and changing the frequency of a reference signal generated by the signal generator, thereby restoring the signal. A receiving apparatus for spread spectrum communication, wherein control is performed so that the phase of a signal does not change. 2. A frequency converter for receiving a signal which is spread spectrum and converted to a high frequency band, and frequency-converts the received signal to an original signal frequency band based on a reference signal generated by a signal generator. Means, spectrum despreading means for despreading the output of the frequency conversion means and restoring the received signal to the original signal, and generating the received signal and the signal from the output of the spectrum despreading means at the signal generator. A phase error detection unit that outputs phase error information of the signal that has been output; and a phase error information detected by the phase error detection unit. The phase error information is supplied to the signal generator, and a frequency of a reference signal generated by the signal generator. And a control means for controlling the phase of the restored original signal so as not to change. Remote communication receiver. 3. A signal which is spread spectrum and converted into a high frequency band, receives the signal, and generates a received signal having the same frequency generated by a signal generator, the phase of which is shifted by 90 degrees.
Based on the two reference signals, each frequency is converted to the original signal frequency band, and the received signal is restored to the original signal by spectrum despreading, phase information is extracted from the restored signal, and based on the phase information, A receiver for spread spectrum communication, wherein the signal generator is controlled to change the frequency of a reference signal generated by the signal generator so that the phase of the restored signal does not change. 4. A first and a second reference having a phase shifted by 90 degrees at the same frequency generated by a signal generator and receiving a signal that has been spread spectrum and converted to a high frequency band. A spreading code for spreading the received signal and a spread code generating means, comprising first and second despreaders for frequency-converting the signal to an original signal frequency band based on the signal and for despreading the spectrum, respectively; A delay lock loop for synchronizing with the despreading spread code output from the base station is frequency-converted to the original signal frequency band based on the first and second reference signals.
The first and second despreaders for synchronizing on the basis of one of the received signals and supplying the despreading code to the first and second despreaders for spectrum despreading. The two types of received signals are despread based on the two reference signals, phase information is extracted from the restored original signal, and the signal generator is controlled based on the extracted phase information. And a control unit that controls a phase of the restored original signal by changing a frequency of a reference signal generated by the signal generator. 5. The receiving apparatus for spread spectrum communication according to claim 4, wherein the despreading codes supplied to the first and second despreaders are the same. 6. A signal which is spread spectrum and converted into a frequency band higher than the signal frequency band, and the received signal is generated by a signal generator. A first and a second signal for performing frequency conversion to the original signal frequency band based on the first and second reference signals, respectively, and performing spectrum despreading.
The despreading code supplied to the first and second despreaders output from the spreading code generator for performing the spectrum despreading is different in type but time. Specifically, the delay lock loop for synchronizing the spread code for spreading the received signal and the despreading spread code is synchronized while maintaining a predetermined phase relationship, and the first and second delay lock loops are synchronized with each other. And synchronizes with one of the two types of received signals that have been frequency-converted to the original signal frequency band based on the reference signal of the first and second despreaders. To extract phase information from the original signal restored by despreading the two types of received signals based on the first and second reference signals, respectively. Based on Controlling the signal generator to change the frequency of the reference signal generated by the signal generator so that the phase of the restored original signal does not change. Receiver. 7. A signal which is spread spectrum and receives a signal converted to a frequency band higher than the signal frequency band, and the received signal is generated by a signal generator and the phase of which is shifted by 90 degrees at the same frequency. A first and a second signal for performing frequency conversion to the original signal frequency band based on the first and second reference signals, respectively, and performing spectrum despreading.
A delay lock loop for synchronizing a spreading code for spreading the received signal with a despreading code output from a spreading code generating means for despreading the spectrum. A spreading code for spreading the received signal and a despreading spread for two types of received signals, each of which is frequency-converted to an original signal frequency band based on the first and second reference signals. The first and second despreading codes are synchronized with a code, and supplied to the first and second despreaders for spectrum despreading, respectively. The phase information is extracted from the restored original signal by despreading the two types of received signals, each of which has been frequency-converted to the original signal frequency band based on the reference signal, and extracting the extracted phase information. Controlling the signal generator based on the information, and changing the frequency of the reference signal generated by the signal generator so as to control the phase of the restored original signal so as not to change. Spread spectrum communication receiver. 8. A receiving apparatus for spread spectrum communication that receives a signal that has been spread spectrum and converted to a frequency band higher than the signal frequency band, wherein the received signal is frequency-converted to an original frequency band, and A receiving apparatus for spread spectrum communication, wherein a signal generating means for despreading a received signal is shared.