JP2738480B2 - Frequency band compression wireless communication system - Google Patents
Frequency band compression wireless communication systemInfo
- Publication number
- JP2738480B2 JP2738480B2 JP4042972A JP4297292A JP2738480B2 JP 2738480 B2 JP2738480 B2 JP 2738480B2 JP 4042972 A JP4042972 A JP 4042972A JP 4297292 A JP4297292 A JP 4297292A JP 2738480 B2 JP2738480 B2 JP 2738480B2
- Authority
- JP
- Japan
- Prior art keywords
- signal
- wireless communication
- band
- frequency band
- modulated
- 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.)
- Expired - Fee Related
Links
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- Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
- Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は周波数帯域圧縮無線通信
方式に係わり、特に帯域制限された音声信号をサンプリ
ング信号で一方並びに他方の音声信号に時分割し、周波
数帯域が圧縮された送信電波で無線通信ができる周波数
帯域圧縮無線通信方式に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency band compression radio communication system, and more particularly, to time-sharing a band-limited audio signal into one and the other by using a sampling signal, and using a transmission radio wave whose frequency band is compressed. The present invention relates to a frequency band compression wireless communication system capable of wireless communication.
【０００２】[0002]
【従来技術および発明が解決すべき課題】通常、音声信
号の周波数帯域が０.３ＫＨｚ〜３.４ＫＨｚの無線通信
方式は図３に示すようにマイク３１、送信用音声信号増
幅器３２、ＬＰＦ３３、ＨＰＦ３４、ＦＭ変調器３５、
水晶３７が接続された搬送波発振器３６、ローカル信号
発振器３９が接続された混合器３８、送信電力増幅器４
０、送信アンテナ４１で構成される無線送信機ＥＱ
11と、受信アンテナ４２、ＲＦ受信回路４３、ＬＰＦ４
４、受信用音声信号増幅器４５、スピーカ４６で構成さ
れる無線受信機ＥＱ12と相互で所定の占有周波数帯域を
有する変調電波を送受する方式である。2. Description of the Related Art Normally, a radio communication system in which the frequency band of an audio signal is 0.3 kHz to 3.4 kHz is a microphone 31, a transmission audio signal amplifier 32, an LPF 33, an HPF 34 as shown in FIG. , FM modulator 35,
A carrier oscillator 36 to which a crystal 37 is connected, a mixer 38 to which a local signal oscillator 39 is connected, a transmission power amplifier 4
0, radio transmitter EQ composed of transmission antenna 41
11 , receiving antenna 42, RF receiving circuit 43, LPF 4
4. A method in which a modulated radio wave having a predetermined occupied frequency band is transmitted and received between the radio receiver EQ 12 including the receiving audio signal amplifier 45 and the speaker 46.
【０００３】無線送信機ＥＱ11のマイク３１は送信用音
声信号増幅器３２、ＬＰＦ３３、ＨＰＦ３４を介して搬
送信号入力側に搬送波発振器３６が接続されたＦＭ変調
器３５の入力側へ接続され、ＦＭ変調器３５の出力側は
混合器３８、送信電力増幅器４０を介して送信アンテナ
４１に接続される。また、無線受信機ＥＱ12の受信アン
テナ４２はＲＦ受信回路４３の入力側と接続され、ＲＦ
受信回路４３の出力側はＬＰＦ４４、受信用音声信号増
幅器４５を介してスピーカ４６に接続される。The microphone 31 of the radio transmitter EQ 11 is connected via a transmission audio signal amplifier 32, LPF 33 and HPF 34 to the input side of an FM modulator 35 in which a carrier signal oscillator is connected to the carrier signal input side. The output side of the mixer 35 is connected to a transmission antenna 41 via a mixer 38 and a transmission power amplifier 40. The receiving antenna 42 of the wireless receiver EQ 12 is connected to the input side of the RF receiving circuit 43,
The output side of the receiving circuit 43 is connected to a speaker 46 via an LPF 44 and a receiving audio signal amplifier 45.
【０００４】上記無線送信機ＥＱ11のマイク３１で生成
された音声信号はＬＰＦ３３とＨＰＦ３４を通過すると
０.３ＫＨｚ〜３.４ＫＨｚの音声信号となる。この０.
３ＫＨｚ〜３.４ＫＨｚの音声信号は搬送波発振器３６
から送出される搬送波ｆcを変調すれば電波形式がＡ３
のＤＳＢ及びＦ３では占有周波数帯域は最小でも６.８
ＫＨｚとなり、所定の電波帯域のチャネル数が限定さ
れ、より以上のチャネルを確保できない等の難点があ
る。なお、変調電波の形式がＡ３ＪのＳＳＢでは占有周
波数帯域は３.４ＫＨｚであるが搬送波の周波数変動が
そのまま音声の周波数を変えるためＶＨＦ以上（３０Ｍ
Ｈｚ）の搬送周波数での使用は困難である。An audio signal generated by the microphone 31 of the radio transmitter EQ 11 becomes an audio signal of 0.3 kHz to 3.4 kHz when passing through the LPF 33 and the HPF 34. This 0.
The audio signal of 3 kHz to 3.4 kHz is supplied to a carrier oscillator 36.
If modulates a carrier f c sent from the radio wave format A3
In DSB and F3, the occupied frequency band is at least 6.8.
KHz, the number of channels in a predetermined radio band is limited, and there are disadvantages such as that more channels cannot be secured. Note that the occupied frequency band is 3.4 KHz in the SSB of the modulated radio wave format of A3J, but the frequency variation of the carrier wave changes the frequency of the voice as it is, so that the VHF or more (30M or more)
(Hz) is difficult to use.
【０００５】[0005]
【発明の目的】本発明は上述した難点に鑑みなされたも
ので、時分割された一方並びに他方の音声信号をＦＭ、
ＡＭ変調し、無線通信装置相互で送受することにより、
所定の電波帯域のチャネル数を増加し、電波帯域の有効
利用が図れる周波数帯域圧縮無線通信方式を提供するこ
とを目的とする。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned difficulties, and it has been proposed that one or the other of the time-divided audio signals be FM,
By performing AM modulation and transmitting and receiving between wireless communication devices,
An object of the present invention is to provide a frequency band compression wireless communication system in which the number of channels in a predetermined radio band is increased and the radio band can be effectively used.
【０００６】[0006]
【課題を解決するための手段】この目的を達成するため
本発明の周波数帯域圧縮無線通信方式は、帯域制限され
た音声信号をサンプリング信号で一方並びに他方の音声
信号に時分割して帯域の等しい２組の音声信号を生成
し、時分割された一方の音声信号をローパスフィルター
で低域を通過させてから搬送波をＦＭ変調して第１の被
変調波を生成し、時分割された他方の音声信号をローパ
スフィルターで低域を通過させてから第１の被変調波を
ＡＭ変調して第２の被変調波を生成し、第２の被変調波
をローカル発振信号で送信電波に変換し、無線通信装置
相互で送信電波を送受するものである。In order to achieve this object, a frequency band compression wireless communication system according to the present invention is arranged such that a band-limited audio signal is time-divided by a sampling signal into one and the other audio signal, and the bands are equal. Two sets of audio signals are generated, one of the time-divided audio signals is passed through a low pass filter with a low-pass filter, and then the carrier is FM-modulated to generate a first modulated wave. After passing the audio signal through a low-pass filter with a low-pass filter, the first modulated wave is AM-modulated to generate a second modulated wave, and the second modulated wave is converted into a transmission radio wave by a local oscillation signal. The transmitting and receiving radio waves are transmitted and received between the wireless communication devices.
【０００７】[0007]
【作用】この周波数帯域圧縮無線通信方式において、帯
域制限された音声信号をサンプリング信号で一方並びに
他方の音声信号に時分割すると０〜１.７ＫＨｚ帯域の
等しい２組の音声信号が生成される。この２組の音声信
号のうち、一方の音声信号をローパスフィルターで低域
を通過させてから変調波をＦＭ変調すると、この第１の
被変調波の占有帯域は３.４ＫＨｚとなる。また、他方
の音声信号をローパスフィルターで低域を通過させてか
ら第１の被変調波をＡＭ変調し第２の被変調波を生成す
ると、第２の被変調波の占有帯域は３.４ＫＨｚとな
る。この第２の被変調波をローカル発振信号で送信電波
に変換すると、送受信電波の占有帯域は始めの音声信号
の帯域に等しくなる。In this frequency band compression radio communication system, when a band-limited audio signal is time-divided into one and the other by a sampling signal, two sets of audio signals having the same band of 0 to 1.7 KHz are generated. When the modulated wave is FM-modulated after passing one of the two audio signals through a low-pass filter with a low-pass filter, the occupied band of the first modulated wave is 3.4 KHz. When the other audio signal is passed through a low-pass filter by a low-pass filter and then the first modulated wave is AM-modulated to generate a second modulated wave, the occupied band of the second modulated wave is 3.4 kHz. Becomes When the second modulated wave is converted into a transmission radio wave by a local oscillation signal, the occupied band of the transmission and reception radio wave becomes equal to the band of the first audio signal.
【０００８】[0008]
【実施例】以下、本発明の周波数帯域圧縮無線通信方式
の一実施例を図１、図２にしたがって詳述する。本発明
の周波数帯域圧縮無線通信方式は図１に示すように、マ
イク１、送信用音声信号増幅器２、帯域通過フィルタ
３、時分割スイッチ４、８ＫＨｚパルスを発振するサン
プリング信号発生器５、１.７ＫＨｚ以下の音声信号を
通過させるＬＰＦ６、１.７ＫＨｚ以下の音声信号を通
過させるＬＰＦ７、ＦＭ変調器１０、ＡＭ変調器１１、
水晶９が接続された搬送波発振器８、ローカル信号発振
器１４が接続された変換器１３、送信電力増幅器１５、
送信アンテナ１６で構成される無線送信機ＥＱ1と、受
信アンテナ２１、ＲＦ受信回路２２、ＡＭ復調器２３、
ＦＭ復調器２４、復調信号サンプリングスイッチ２５、
８ＫＨｚ方形波を発振する復調サンプリング信号発生器
２６、ＬＰＦ２７、受信用音声信号増幅器２８、スピー
カ２９で構成される無線受信機ＥＱ2との相互で所定の
占有周波数帯域を有する変調電波を送受する方式であ
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the frequency band compression wireless communication system according to the present invention will be described below in detail with reference to FIGS. As shown in FIG. 1, a frequency band compression wireless communication system according to the present invention includes a microphone 1, a transmission audio signal amplifier 2, a band-pass filter 3, a time division switch 4, a sampling signal generator 5, which oscillates 8 KHz pulses, and 1. LPF 6 that passes audio signals of 7 KHz or less, LPF 7 that passes audio signals of 1.7 KHz or less, FM modulator 10, AM modulator 11,
A carrier oscillator 8 to which a crystal 9 is connected, a converter 13 to which a local signal oscillator 14 is connected, a transmission power amplifier 15,
A radio transmitter EQ 1 composed of a transmission antenna 16, a reception antenna 21, an RF reception circuit 22, an AM demodulator 23,
FM demodulator 24, demodulated signal sampling switch 25,
A method of transmitting and receiving a modulated radio wave having a predetermined occupied frequency band to and from a wireless receiver EQ 2 including a demodulated sampling signal generator 26, an LPF 27, a receiving audio signal amplifier 28, and a speaker 29 oscillating an 8 kHz square wave. It is.
【０００９】無線送信機ＥＱ1のマイク１は送信用音声
信号増幅器２、帯域通過フィルタ３を介して時分割スイ
ッチ４の入力側４ｃと接続され、時分割スイッチ４の一
方の出力側４ｂはＬＰＦ６を介して搬送波入力側に搬送
波発振器８が接続されたＦＭ変調器１０の入力側へ接続
される。また、ＦＭ変調器１０の出力側はＡＭ変調器１
１の搬送波入力側に接続され、ＡＭ変調器１１の入力側
には時分割スイッチ４の他方の出力側４ａが接続された
ＬＰＦ７が接続される。ＡＭ変調器１１の出力側は変換
器１３、送信電力増幅器１５を介して送信アンテナ１６
に接続される。The microphone 1 of the radio transmitter EQ 1 is connected to the input 4c of the time division switch 4 via the transmission audio signal amplifier 2 and the band pass filter 3, and one output 4b of the time division switch 4 is connected to the LPF 6 Is connected to the input side of the FM modulator 10 in which the carrier wave oscillator 8 is connected to the carrier wave input side. The output side of the FM modulator 10 is an AM modulator 1
The LPF 7 to which the other output side 4a of the time division switch 4 is connected is connected to the input side of the AM modulator 11 and to the input side of one carrier wave. The output side of the AM modulator 11 is connected to a transmission antenna 16 via a converter 13 and a transmission power amplifier 15.
Connected to.
【００１０】無線受信機ＥＱ2の受信アンテナ２１はＲ
Ｆ受信回路２２の入力側と接続され、ＲＦ受信回路２２
の出力側はＡＭ復調器２３とＦＭ復調器２４のそれぞれ
の入力側と接続される。また、ＡＭ復調器２３とＦＭ復
調器２４の出力側は復調サンプリング信号発生器２６か
ら復調サンプリング信号を入力される復調信号サンプリ
ングスイッチ２５の一方並びに他方の入力側と接続さ
れ、復調信号サンプリングスイッチ２５の出力側２５ａ
はＬＰＦ２７、受信用音声信号増幅器２８を介してスピ
ーカ２９に接続される。The receiving antenna 21 of the radio receiver EQ 2 is R
F receiving circuit 22 is connected to the input side of RF receiving circuit 22.
Is connected to respective input sides of the AM demodulator 23 and the FM demodulator 24. The output sides of the AM demodulator 23 and the FM demodulator 24 are connected to one and the other input sides of a demodulation signal sampling switch 25 to which a demodulation sampling signal is input from a demodulation sampling signal generator 26. Output side 25a
Is connected to a speaker 29 via an LPF 27 and a receiving audio signal amplifier 28.
【００１１】この周波数帯域圧縮無線通信方式におい
て、無線送信機ＥＱ1のマイク１で生成された音声信号
は帯域通過フィルタ３を通過すると図１の点の波形は
図２の波形に示すように０.３ＫＨｚ〜３.４ＫＨｚの
音声信号となる。この０.３ＫＨｚ〜３.４ＫＨｚの音声
信号が時分割スイッチ４の入力側４ｃに送出されるとサ
ンプリング信号発生器５から送出される波形の８ＫＨ
ｚパルスで時分割される。時分割スイッチ４の出力側４
ｂの出力側４ａの出力は８ＫＨｚのサンプリング信号を
一つおきに取り出しているため、それぞれ位相が異なる
が、図２のの点線と実線で示す４ＫＨｚのサンプリン
グパルス列となる。このため時分割スイッチ４の一方の
出力側４ｂに接続されたＬＰＦ６の入、出力は０〜１.
７ＫＨｚ、他方の出力側４ａに接続されたＬＰＦ７の
入、出力もまた、０〜１.７ＫＨｚとなる。このため、
時分割スイッチ４の一方の出力側４ｂと他方の出力側４
ａはそれぞれ図１の、に示すようになり、ＬＰＦ６
の出力とＬＰＦ７の出力は図２の波形に同期して、
実線の時分割Ａ群及び、点線の時分割Ｂ群で時分割され
る。波形の実線の時分割Ａ群をエンベロープとする０
〜１.７ＫＨｚのスペクトルをもつ第１の被変調波とな
る。この第１の被変調波の占有帯域は始めの音声信号の
帯域と等しくなり、スペクトルには搬送波発振器８で生
成された搬送波が含まれている。この搬送波が含まれて
いる被変調波でＡＭ変調すると、０〜３.４ＫＨｚの
波形となり、送信電波の占有帯域は始めの音声信号の帯
域に等しい３.４ＫＨｚとなる。In this frequency band compression radio communication system, when the audio signal generated by the microphone 1 of the radio transmitter EQ 1 passes through the band pass filter 3, the waveform at the point in FIG. 1 becomes 0 as shown in the waveform in FIG. It becomes a voice signal of 0.3 kHz to 3.4 kHz. When the sound signal of 0.3 kHz to 3.4 kHz is transmitted to the input side 4c of the time division switch 4, the waveform of the waveform transmitted from the sampling signal generator 5 is 8KH.
Time division is performed by z pulses. Output side 4 of time division switch 4
Since the output of the output side 4a of FIG. 2b takes out every other sampling signal of 8 KHz, the phases are different from each other, but a sampling pulse train of 4 KHz shown by a dotted line and a solid line in FIG. Therefore, the input and output of the LPF 6 connected to one output side 4b of the time division switch 4 are 0 to 1.
7 KHz, the input and output of the LPF 7 connected to the other output side 4a also become 0 to 1.7 KHz. For this reason,
One output 4b of the time-division switch 4 and the other output 4
a are as shown in FIG. 1 respectively, and LPF6
And the output of LPF 7 are synchronized with the waveform of FIG.
The time division is performed by a time division A group indicated by a solid line and a time division B group indicated by a dotted line. Time-sharing group A indicated by a solid line in the waveform is defined as an envelope 0
It becomes the first modulated wave having a spectrum of up to 1.7 KHz. The occupied band of the first modulated wave is equal to the band of the first voice signal, and the spectrum includes the carrier generated by the carrier oscillator 8. When AM modulation is performed on the modulated wave including the carrier, the waveform becomes 0 to 3.4 KHz, and the occupied band of the transmission radio wave is 3.4 KHz, which is equal to the band of the first audio signal.
【００１２】上記実施例では信号波を音声信号として説
明したが、映像信号等の他のアナログ信号であつてもよ
い。In the above embodiment, the signal wave is described as an audio signal, but may be another analog signal such as a video signal.
【００１３】[0013]
【発明の効果】以上の説明からも明らかなように本発明
の周波数帯域圧縮無線通信方式によれば、時分割されて
帯域の等しい２組の音声信号が生成された一方並びに他
方の音声信号をＦＭ、ＡＭ変調し、無線通信装置相互で
送受することにより、所定の電波帯域のチャネル数を増
加し、電波帯域の有効利用が図れる。As is clear from the above description, according to the frequency band compression wireless communication system of the present invention, one and the other audio signals generated by time-divisionally generating two sets of audio signals having the same band are generated. By performing FM and AM modulation and transmitting and receiving between wireless communication devices, the number of channels in a predetermined radio band can be increased, and the radio band can be effectively used.
【図１】本発明の周波数帯域圧縮無線通信方式の一実施
例を示すブロック図。FIG. 1 is a block diagram showing an embodiment of a frequency band compression wireless communication system according to the present invention.
【図２】本発明の周波数帯域圧縮無線通信方式の特性
図。FIG. 2 is a characteristic diagram of a compressed frequency band wireless communication system according to the present invention.
【図３】従来の無線通信方式のブロック図。FIG. 3 is a block diagram of a conventional wireless communication system.
３・・・・・・帯域通過フィルタ ４・・・・・・時分割スイッチ ６・・・・・・ＬＰＦ ７・・・・・・ＬＰＦ １０・・・・・・ＦＭ変調器 １１・・・・・・ＡＭ変調器 １３・・・・・・変換器 １４・・・・・・ローカル信号発振器 ＥＱ1・・・・・・無線送信機 ＥＱ2・・・・・・無線受信機3 bandpass filter 4 time division switch 6 LPF 7 LPF 10 FM modulator 11 … AM modulator 13 …… Converter 14 …… Local signal oscillator EQ 1 …… Wireless transmitter EQ 2 …… Wireless receiver
Claims (1)
生器（５）からのサンプリング信号で時分割スイッチ手
段（４）により一方及び他方の信号に時分割して帯域の
等しい２組の信号を生成し、時分割された一方の信号を
ローパスフィルター（６）で低域を通過させてから搬送
波をＦＭ変調して第１の被変調波を生成し、時分割され
た他方の信号をローパスフィルター（７）で低域を通過
させてから前記第１の被変調波をＡＭ変調して第２の被
変調波を生成し、前記第２の被変調波をローカル発振信
号で送信電波に変換し、無線通信装置（ＥＱ1、ＥＱ2）
相互で送信電波を送受することを特徴とする周波数帯域
圧縮無線通信方式。A band-limited signal is time-divided into one and the other signal by a time-division switch means (4) using a sampling signal from a sampling signal generator (5) .
Two equal sets of signals are generated , one of the time-divided signals is passed through a low-pass filter (6) in a low band, and then the carrier is FM-modulated to generate a first modulated wave, which is time-divided. The other signal is passed through a low-pass filter (7) in a low band, and then the first modulated wave is AM-modulated to generate a second modulated wave, and the second modulated wave is converted to a local oscillation signal. Is converted to a transmission radio wave by a wireless communication device (EQ 1 , EQ 2 )
A frequency band compression wireless communication system characterized by mutually transmitting and receiving transmission radio waves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4042972A JP2738480B2 (en) | 1992-02-28 | 1992-02-28 | Frequency band compression wireless communication system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4042972A JP2738480B2 (en) | 1992-02-28 | 1992-02-28 | Frequency band compression wireless communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05244035A JPH05244035A (en) | 1993-09-21 |
| JP2738480B2 true JP2738480B2 (en) | 1998-04-08 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4042972A Expired - Fee Related JP2738480B2 (en) | 1992-02-28 | 1992-02-28 | Frequency band compression wireless communication system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2738480B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106170113B (en) * | 2016-09-29 | 2020-05-22 | 北京奇艺世纪科技有限公司 | Method and device for eliminating noise and electronic equipment |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5417522B2 (en) * | 1973-05-21 | 1979-06-30 | ||
| JPS6378690A (en) * | 1986-09-22 | 1988-04-08 | Matsushita Electric Ind Co Ltd | Video signal processor |
| JPH0219662A (en) * | 1988-07-08 | 1990-01-23 | Takeo Hanashiro | Pumping device |
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1992
- 1992-02-28 JP JP4042972A patent/JP2738480B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05244035A (en) | 1993-09-21 |
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