JPH06252881A - Spread spectrum communications equipment - Google Patents
Spread spectrum communications equipmentInfo
- Publication number
- JPH06252881A JPH06252881A JP5035956A JP3595693A JPH06252881A JP H06252881 A JPH06252881 A JP H06252881A JP 5035956 A JP5035956 A JP 5035956A JP 3595693 A JP3595693 A JP 3595693A JP H06252881 A JPH06252881 A JP H06252881A
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- JP
- Japan
- Prior art keywords
- spread spectrum
- section
- information
- signal
- unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はスペクトラム拡散通信装
置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spread spectrum communication device.
【０００２】[0002]
【従来の技術】近年、スペクトラム拡散通信装置は、多
元接続性、秘話性、耐干渉性などに優れた通信方式を用
いているため、軍用通信だけでなく公共通信やパーソナ
ル通信にも利用されるようになった。2. Description of the Related Art In recent years, spread spectrum communication devices are used not only for military communication but also for public communication and personal communication because they use a communication method having excellent multiple access, confidentiality and interference resistance. It became so.
【０００３】従来のスペクトラム拡散通信装置は図２に
示すように構成されている。スペクトラム拡散通信装置
は送信部１と受信部２ならびに共用器７などで構成され
ている。送信部１は、情報信号に誤り訂正符号化を行う
誤り訂正符号部３と、誤り訂正符号化後の信号に情報変
調を行う情報変調部４と、情報変調後の信号をスペクト
ラム拡散変調するスペクトラム拡散変調部５〔以下、Ｓ
Ｓ変調部５と称す〕と、スペクトラム拡散信号を無線周
波数帯域に周波数変換する送信周波数変換部６とで構成
されており、送信周波数変換部６の出力が送受信の信号
を分ける共用器７を介してアンテナ８に接続されてい
る。アンテナ８で受信された信号は共用器７を介して受
信部２に供給されている。受信部２は、無線周波数帯域
の信号を中間周波数に変換する受信周波数変換部９と、
周波数変換後の信号をスペクトラム拡散復調するスペク
トラム拡散復調部１０〔以下、ＳＳ復調部１０と称す〕
と、スペクトラム拡散復調後の信号を情報復調する情報
復調部１１と、情報復調後の信号を元の情報信号に復号
する誤り訂正復号部１２とで構成されている。A conventional spread spectrum communication device is constructed as shown in FIG. The spread spectrum communication device comprises a transmitter 1, a receiver 2, a duplexer 7, and the like. The transmission unit 1 includes an error correction coding unit 3 that performs error correction coding on an information signal, an information modulation unit 4 that performs information modulation on the signal after error correction coding, and a spectrum that spread spectrum modulates the signal after information modulation. Spreading modulator 5 [hereinafter, S
S-modulation unit 5] and a transmission frequency conversion unit 6 for frequency-converting a spread spectrum signal into a radio frequency band. The output of the transmission frequency conversion unit 6 passes through a duplexer 7 for dividing a transmission signal and a reception signal. Connected to the antenna 8. The signal received by the antenna 8 is supplied to the receiving unit 2 via the duplexer 7. The reception unit 2 includes a reception frequency conversion unit 9 that converts a signal in a radio frequency band into an intermediate frequency,
Spread spectrum demodulation unit 10 [hereinafter referred to as SS demodulation unit 10] for spread spectrum demodulating the signal after frequency conversion
And an information demodulation section 11 for demodulating the signal after spread spectrum demodulation, and an error correction decoding section 12 for decoding the signal after information demodulation into the original information signal.
【０００４】このように構成された従来のスペクトラム
拡散通信装置について、以下その動作を説明する。ま
ず、送信部１は誤り訂正符号部３で情報信号に誤り訂正
符号化を行い、情報変調部４で位相シフトキーイングな
どの情報変調を行う。次に、ＳＳ変調部５でスペクトラ
ム拡散変調し、送信周波数変換部６で無線周波数帯域に
周波数変換し、共用器７を通して、アンテナ８で無線信
号を送信する。また、受信時には、アンテナ８で無線信
号を受信し、共用器７を通して、受信部２に入力する。
受信部２は受信周波数変換部９で無線周波数帯域の信号
を中間周波数に変換し、ＳＳ復調部１０でスペクトラム
拡散復調する。次に、情報復調部１１で位相シフトキー
イングなどの情報復調を行い、誤り訂正復号部１２で元
の情報信号に復号する。The operation of the conventional spread spectrum communication apparatus thus configured will be described below. First, in the transmission unit 1, the error correction coding unit 3 performs error correction coding on the information signal, and the information modulation unit 4 performs information modulation such as phase shift keying. Next, the SS modulator 5 performs spread spectrum modulation, the transmission frequency converter 6 performs frequency conversion into a radio frequency band, and the antenna 8 transmits the radio signal through the duplexer 7. When receiving, a radio signal is received by the antenna 8 and input to the receiving unit 2 through the duplexer 7.
In the reception unit 2, the reception frequency conversion unit 9 converts the signal in the radio frequency band into an intermediate frequency, and the SS demodulation unit 10 performs spread spectrum demodulation. Next, the information demodulation unit 11 performs information demodulation such as phase shift keying, and the error correction decoding unit 12 decodes the original information signal.
【０００５】[0005]
【発明が解決しようとする課題】このような構成では、
多元接続性、秘話性、耐干渉性などに優れたスペクトラ
ム拡散通信が可能となるが、無線周波数帯域の有効利用
に寄与できるものが要望されている。SUMMARY OF THE INVENTION With such a configuration,
Although spread spectrum communication that is excellent in multi-access, confidentiality, and interference resistance is possible, what can contribute to effective use of the radio frequency band is desired.
【０００６】本発明はスペクトラム拡散通信の特性を損
なうことなく無線周波数帯域の有効利用に寄与できるス
ペクトラム拡散通信装置を提供することを目的とする。An object of the present invention is to provide a spread spectrum communication device which can contribute to effective use of a radio frequency band without impairing the characteristics of spread spectrum communication.
【０００７】[0007]
【課題を解決するための手段】本発明のスペクトラム拡
散通信装置は、スペクトラム拡散通信方式を用いて無線
信号を送信する送信部と、スペクトラム拡散通信方式の
無線信号を受信する受信部とからなり、前記送信部に
は、情報信号に情報変調を行う情報変調部と、前記情報
変調部の出力信号をスペクトラム拡散変調するスペクト
ラム拡散変調部と、前記スペクトラム拡散変調部の出力
信号を無線周波数帯域に周波数変換する送信周波数変換
部とを設け、前記受信部には、無線周波数帯域の信号を
中間周波数に周波数変換する受信周波数変換部と、前記
受信周波数変換部の出力信号をスペクトラム拡散復調す
るスペクトラム拡散復調部と、前記スペクトラム拡散復
調部の出力信号を元の情報信号に情報復調する情報復調
部と、ビット誤り率を測定する誤り率測定部とを設け、
誤り率測定部の測定結果に応じて前記情報変調部と前記
情報復調部の情報変調方式を変更するよう構成したこと
を特徴とする。A spread spectrum communication device according to the present invention comprises a transmitter for transmitting a radio signal using a spread spectrum communication system and a receiver for receiving a radio signal according to the spread spectrum communication system. The transmitter includes an information modulator that performs information modulation on an information signal, a spread spectrum modulator that spread spectrum modulates the output signal of the information modulator, and a frequency of the output signal of the spread spectrum modulator in a radio frequency band. A transmission frequency conversion unit for conversion is provided, and the reception unit includes a reception frequency conversion unit that frequency-converts a signal in a radio frequency band to an intermediate frequency, and a spread spectrum demodulation that spread spectrum demodulates an output signal of the reception frequency conversion unit. Section, an information demodulation section for demodulating the output signal of the spread spectrum demodulation section into an original information signal, and a bit error rate Provided an error rate measuring unit that measures,
It is characterized in that the information modulation method of the information modulation section and the information demodulation section is changed according to the measurement result of the error rate measurement section.
【０００８】[0008]
【作用】この構成によると、スペクトラム拡散通信にお
いて伝搬路状況に応じて情報変調部の情報変調方式を変
更することによって周波数帯域幅を狭くできる。According to this structure, the frequency bandwidth can be narrowed by changing the information modulation method of the information modulator in accordance with the propagation path condition in spread spectrum communication.
【０００９】[0009]
【実施例】以下、本発明のスペクトラム拡散通信装置の
一実施例を図１に基づいて説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the spread spectrum communication device of the present invention will be described below with reference to FIG.
【００１０】従来例と同様の作用をなすものには同一の
符号を付けて説明する。ただし、図２に示すスペクトラ
ム拡散通信装置では、送信部１の情報変調部４と受信部
２の情報復調部11については変調方式が固定であったの
に対して、図１に示す本発明のスペクトラム拡散通信装
置では、送信部１の情報変調部４の変調方式と受信部２
の情報復調部11の復調方式を変更できるように構成され
ている。この情報変調部４と情報復調部11の変調方式の
切り換えは、誤り訂正復号部１２の出力側に設けられて
ビット誤り率を測定する誤り率測定部１３の測定結果に
応じて切り換えられる。Components having the same functions as those of the conventional example will be described with the same reference numerals. However, in the spread spectrum communication device shown in FIG. 2, the modulation method is fixed for the information modulation section 4 of the transmission section 1 and the information demodulation section 11 of the reception section 2, whereas in the present invention shown in FIG. In the spread spectrum communication device, the modulation method of the information modulator 4 of the transmitter 1 and the receiver 2
The information demodulation unit 11 is configured so that the demodulation method can be changed. The switching of the modulation schemes of the information modulation unit 4 and the information demodulation unit 11 is switched according to the measurement result of the error rate measurement unit 13 provided on the output side of the error correction decoding unit 12 and measuring the bit error rate.
【００１１】以上のように構成されたスペクトラム拡散
通信装置について、以下その動作を説明する。まず、送
信部１は誤り訂正符号部３で情報信号に誤り訂正符号化
を行い、情報変調部４で位相シフトキーイングなどの情
報変調を行う。次に、ＳＳ変調部５でスペクトラム拡散
変調し、送信周波数変換部６で無線周波数帯域に周波数
変換し、共用器７を通して、アンテナ８で無線信号を送
信する。また、受信時には、アンテナ８で無線信号を受
信し、共用器７を通して、受信部２に入力する。受信部
２は受信周波数変換部９で無線周波数帯域の信号を中間
周波数に変換し、ＳＳ復調部１０でスペクトラム拡散復
調する。次に、情報復調部１１で位相シフトキーイング
などの情報復調を行い、誤り訂正復号部１２で元の情報
信号に復号する。The operation of the spread spectrum communication device configured as described above will be described below. First, in the transmission unit 1, the error correction coding unit 3 performs error correction coding on the information signal, and the information modulation unit 4 performs information modulation such as phase shift keying. Next, the SS modulator 5 performs spread spectrum modulation, the transmission frequency converter 6 performs frequency conversion into a radio frequency band, and the antenna 8 transmits the radio signal through the duplexer 7. When receiving, a radio signal is received by the antenna 8 and input to the receiving unit 2 through the duplexer 7. In the reception unit 2, the reception frequency conversion unit 9 converts the signal in the radio frequency band into an intermediate frequency, and the SS demodulation unit 10 performs spread spectrum demodulation. Next, the information demodulation unit 11 performs information demodulation such as phase shift keying, and the error correction decoding unit 12 decodes the original information signal.
【００１２】誤り率測定部１３ではビット誤り率を測定
し、ビット誤り率が小さいときは伝搬路の状況が良いと
判断し、情報変調部４の変調方式を変化させて周波数利
用率を大きくする。すると、情報変調後の周波数帯域幅
が従来例と比べて狭くなり、スペクトラム拡散変調し、
周波数変換した後に共用器７を通してアンテナ８から送
信する無線信号の占有周波数帯域幅も従来例と比べて狭
くなる。受信部２では、入力した受信信号を周波数変換
し、スペクトラム拡散変調した後に情報復調部１１にお
いて誤り率測定部１３によって変えられた変調方式で情
報復調を行う。ここで、情報復調部１１の変調方式は、
誤り率測定部１３によって情報変調部４と同じ変調方式
に変えられている。The error rate measuring unit 13 measures the bit error rate. When the bit error rate is small, it is judged that the condition of the propagation path is good, and the modulation method of the information modulating unit 4 is changed to increase the frequency utilization rate. . Then, the frequency bandwidth after information modulation becomes narrower than the conventional example, and spread spectrum modulation is performed.
The occupied frequency bandwidth of the radio signal transmitted from the antenna 8 through the duplexer 7 after frequency conversion is also narrower than that of the conventional example. In the receiving section 2, the input received signal is frequency-converted, spread spectrum modulated, and then, in the information demodulating section 11, information demodulation is performed by the modulation method changed by the error rate measuring section 13. Here, the modulation method of the information demodulation unit 11 is
The error rate measuring unit 13 has changed to the same modulation method as the information modulating unit 4.
【００１３】具体的には、誤り率測定部１３が“ ビッ
ト誤り率が小さい ”と測定結果を出した場合には、情
報変調部４と情報復調部11の情報変調の方式を２相位相
シフトキーイング（ＢＰＳＫ）から４相位相シフトキー
イング（ＱＰＳＫ）に変更する。すると、ＢＰＳＫの周
波数利用率は最大“１ bit／ｓ／ＨZ ”であり、ＱＰＳ
Ｋの周波数利用率は最大“２ bit／ｓ／ＨZ ”であるの
で、情報変調後の周波数帯域幅が従来例の“１／２”に
なり、アンテナ８から送信される無線信号の占有周波数
帯域幅も“１／２”になり、同じ帯域幅で２倍の信号が
伝送できることになる。ここで、周波数利用率とは、単
位帯域幅当たりにおける伝送可能な情報ビットレートで
あり、この値が大きいほど周波数の有効利用が図れるこ
とになる。Specifically, when the error rate measuring unit 13 outputs a measurement result "the bit error rate is small", the information modulation method of the information modulation unit 4 and the information demodulation unit 11 is changed to a two-phase phase shift. Change from keying (BPSK) to 4-phase phase shift keying (QPSK). Then, the frequency utilization rate of BPSK is the maximum "1 bit / s / H Z ", QPS
Since the maximum frequency utilization rate of K is “2 bit / s / H Z ”, the frequency bandwidth after information modulation is “1/2” of the conventional example, and the occupied frequency of the radio signal transmitted from the antenna 8 is The bandwidth is also "1/2", which means that twice the signal can be transmitted with the same bandwidth. Here, the frequency utilization rate is the information bit rate that can be transmitted per unit bandwidth, and the larger this value, the more effective the frequency can be used.
【００１４】このように本発明のスペクトラム拡散通信
装置によると、ビット誤り率が小さいとき、すなわち、
伝搬路の状況が良いときには周波数の有効利用が可能に
なる。As described above, according to the spread spectrum communication apparatus of the present invention, when the bit error rate is small, that is,
When the condition of the propagation path is good, the frequency can be effectively used.
【００１５】[0015]
【発明の効果】以上のように本発明によると、送信部に
は、情報信号に情報変調を行う情報変調部と、前記情報
変調部の出力信号をスペクトラム拡散変調するスペクト
ラム拡散変調部と、前記スペクトラム拡散変調部の出力
信号を無線周波数帯域に周波数変換する送信周波数変換
部とを設け、前記受信部には、無線周波数帯域の信号を
中間周波数に周波数変換する受信周波数変換部と、前記
受信周波数変換部の出力信号をスペクトラム拡散復調す
るスペクトラム拡散復調部と、前記スペクトラム拡散復
調部の出力信号を元の情報信号に情報復調する情報復調
部と、ビット誤り率を測定する誤り率測定部とを設け、
誤り率測定部の測定結果に応じて前記情報変調部と前記
情報復調部の情報変調方式を変更するよう構成したた
め、ビット誤り率が小さいときには、情報変調方式を変
えて周波数利用率を大きくすることにより、占有周波数
帯域幅を狭くし、周波数の有効利用を達成できるもので
ある。As described above, according to the present invention, the transmitting section includes an information modulating section for performing information modulation on an information signal, a spread spectrum modulating section for performing spread spectrum modulation on an output signal of the information modulating section, and A transmission frequency conversion unit that frequency-converts the output signal of the spread spectrum modulation unit into a radio frequency band is provided, and the reception unit includes a reception frequency conversion unit that frequency-converts a signal in the radio frequency band into an intermediate frequency, and the reception frequency. A spread spectrum demodulation unit that spread spectrum demodulates the output signal of the conversion unit, an information demodulation unit that demodulates the output signal of the spread spectrum demodulation unit to the original information signal, and an error rate measurement unit that measures the bit error rate. Provided,
Since the information modulation method of the information modulation section and the information demodulation section is changed according to the measurement result of the error rate measurement section, when the bit error rate is small, the information modulation method is changed to increase the frequency utilization rate. Thus, the occupied frequency bandwidth can be narrowed and effective use of frequency can be achieved.
【図１】本発明のスペクトラム拡散通信装置の一実施例
の構成図である。FIG. 1 is a configuration diagram of an embodiment of a spread spectrum communication device of the present invention.
【図２】従来のスペクトラム拡散通信装置の構成図であ
る。FIG. 2 is a configuration diagram of a conventional spread spectrum communication device.
１ 送信部 ２ 受信部 ３ 誤り訂正符号部 ４ 情報変調部 ５ ＳＳ変調部 ６ 送信周波数変換部 ７ 共用器 ８ アンテナ ９ 受信周波数変換部 １０ ＳＳ復調部 １１ 情報復調部 １２ 誤り訂正復号部 １３ 誤り率測定部 1 Transmitter 2 Receiver 3 Error Correction Coder 4 Information Modulator 5 SS Modulator 6 Transmission Frequency Converter 7 Duplexer 8 Antenna 9 Reception Frequency Converter 10 SS Demodulator 11 Information Demodulator 12 Error Correction Decoder 13 Error Rate Measuring unit
Claims (2)
信号を送信する送信部と、スペクトラム拡散通信方式の
無線信号を受信する受信部とからなり、前記送信部に
は、情報信号に情報変調を行う情報変調部と、前記情報
変調部の出力信号をスペクトラム拡散変調するスペクト
ラム拡散変調部と、前記スペクトラム拡散変調部の出力
信号を無線周波数帯域に周波数変換する送信周波数変換
部とを設け、前記受信部には、無線周波数帯域の信号を
中間周波数に周波数変換する受信周波数変換部と、前記
受信周波数変換部の出力信号をスペクトラム拡散復調す
るスペクトラム拡散復調部と、前記スペクトラム拡散復
調部の出力信号を元の情報信号に情報復調する情報復調
部と、ビット誤り率を測定する誤り率測定部とを設け、
誤り率測定部の測定結果に応じて前記情報変調部と前記
情報復調部の情報変調方式を変更するよう構成したスペ
クトラム拡散通信装置。1. A transmission section for transmitting a radio signal using a spread spectrum communication system, and a reception section for receiving a radio signal according to a spread spectrum communication system. The transmission section performs information modulation on an information signal. An information modulation section, a spread spectrum modulation section that spread spectrum modulates the output signal of the information modulation section, and a transmission frequency conversion section that frequency converts the output signal of the spread spectrum modulation section to a radio frequency band are provided, and the reception section Includes a reception frequency conversion unit that frequency-converts a signal in a radio frequency band to an intermediate frequency, a spread spectrum demodulation unit that performs spread spectrum demodulation on the output signal of the reception frequency conversion unit, and an output signal of the spread spectrum demodulation unit. An information demodulation section for demodulating information into the information signal of and an error rate measurement section for measuring a bit error rate are provided,
A spread spectrum communication device configured to change the information modulation method of the information modulation section and the information demodulation section according to the measurement result of the error rate measurement section.
判定した場合に、情報変調の方式を２相位相シフトキー
イング（ＢＰＳＫ）から４相位相シフトキーイング（Ｑ
ＰＳＫ）に変更する請求項１記載のスペクトラム拡散通
信装置。2. When the error rate measuring unit determines that the bit error rate is small, the method of information modulation is changed from 2-phase phase shift keying (BPSK) to 4-phase phase shift keying (Q).
The spread spectrum communication device according to claim 1, wherein the spread spectrum communication device is changed to PSK).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5035956A JPH06252881A (en) | 1993-02-25 | 1993-02-25 | Spread spectrum communications equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5035956A JPH06252881A (en) | 1993-02-25 | 1993-02-25 | Spread spectrum communications equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06252881A true JPH06252881A (en) | 1994-09-09 |
Family
ID=12456431
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5035956A Pending JPH06252881A (en) | 1993-02-25 | 1993-02-25 | Spread spectrum communications equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06252881A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08195699A (en) * | 1995-01-18 | 1996-07-30 | Nec Corp | Spread spectrum communication device |
| KR100530277B1 (en) * | 1997-03-17 | 2006-02-28 | 해리스 코포레이션 | High Communication Speed Diffusion Spectrum Transceiver and Related Methods |
| US7359424B2 (en) | 2000-06-28 | 2008-04-15 | Nec Corporation | Spread spectrum communication system and method therefor |
| US8228164B2 (en) | 2007-02-19 | 2012-07-24 | Mitsubishi Electric Corporation | Remote control system for car-mounted device |
-
1993
- 1993-02-25 JP JP5035956A patent/JPH06252881A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08195699A (en) * | 1995-01-18 | 1996-07-30 | Nec Corp | Spread spectrum communication device |
| KR100530277B1 (en) * | 1997-03-17 | 2006-02-28 | 해리스 코포레이션 | High Communication Speed Diffusion Spectrum Transceiver and Related Methods |
| US7359424B2 (en) | 2000-06-28 | 2008-04-15 | Nec Corporation | Spread spectrum communication system and method therefor |
| US8228164B2 (en) | 2007-02-19 | 2012-07-24 | Mitsubishi Electric Corporation | Remote control system for car-mounted device |
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