JPH03214928A - AM receiver - Google Patents
AM receiverInfo
- Publication number
- JPH03214928A JPH03214928A JP2009921A JP992190A JPH03214928A JP H03214928 A JPH03214928 A JP H03214928A JP 2009921 A JP2009921 A JP 2009921A JP 992190 A JP992190 A JP 992190A JP H03214928 A JPH03214928 A JP H03214928A
- Authority
- JP
- Japan
- Prior art keywords
- frequency amplifier
- attenuation
- signal
- intermediate frequency
- automatic gain
- 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.)
- Pending
Links
Landscapes
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
- Superheterodyne Receivers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
不発明け自動利得調整器金使用する届受信機に関する．
従来の技術
第２図は従来のＡＭ受＠機の要部ブロック図の一例’ｋ
示す．第２図において、アンテナ１よシ入力された受信
希望信号は受信局波増幅器２で増幅され、次段の周波数
変換器３で中間周波数に周波数変換され、中間周波増幅
器４で再度増幅され、検波器５で音声信号に琥換される
．受信希望信号が十分に大きい場合、自動利得調整器６
が動作し、受信周波増幅器２の増幅度を下げ、また受信
希望信号が極端に大きい場合は減衰させる．中間周波増
幅器４でもその入力信号が十分大きい場合、自動利得調
整器７が動作し、中間周波増幅器４の増幅度を下げる。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a receiver using an automatic gain adjuster in an industrial field of application. Conventional technology Figure 2 is an example of a block diagram of the main parts of a conventional AM receiver.
show. In Fig. 2, a signal to be received inputted from an antenna 1 is amplified by a receiving station wave amplifier 2, frequency-converted to an intermediate frequency by a frequency converter 3 in the next stage, amplified again by an intermediate frequency amplifier 4, and then detected. The signal is converted into an audio signal in device 5. If the desired signal to be received is sufficiently large, the automatic gain adjuster 6
operates, lowers the amplification degree of the reception frequency amplifier 2, and attenuates the signal desired to be received if it is extremely large. If the input signal to the intermediate frequency amplifier 4 is sufficiently large, the automatic gain adjuster 7 operates to lower the amplification degree of the intermediate frequency amplifier 4.
これらの自動利得調整器６および７の目的ＦｉＡＭｆ調
ざれたアンテナ入力信号が店復調される以前に振幅制限
され出力音声信号が歪まないようにすることが目的であ
り、通常中間周波増幅器４の自動利得調整器７の動作す
る受信入力信号の大きさの方が受信周波増幅器２の自動
利得調整器７の動作する受信入方信号の大きさより大き
い．
発明が解一決しようとする課題
ところが、アンテナよりλカされる信号は希望信号のみ
ではなく多くの信号が入ってくる．受信希望信号以外の
信号を妨害信号と考えると、受信周披増幅器には受信希
望信号以外にも多くの妨害信号が入っており、受信周波
増幅器の帯域内に大きな妨害儒号がある場合、ｌｆｒ望
信号が小さくて本受信周波増幅器の自動利得調整器が動
作してしまう．したがって、希望信号が十分大きい場合
には問題とならないが、小さい場合に＃″ｉ希望信号が
受信周波増幅器で増幅されず、妨害信号がない場合に比
べ受信感度が低下する感度抑圧という問題が発生する。The purpose of these automatic gain adjusters 6 and 7 is to limit the amplitude of the FiAMf modulated antenna input signal before it is demodulated so that the output audio signal is not distorted. The magnitude of the received input signal on which the gain adjuster 7 operates is greater than the magnitude of the received input signal on which the automatic gain adjuster 7 of the reception frequency amplifier 2 operates. The problem that the invention aims to solve is that the signal received by the antenna is not only the desired signal but also many other signals. Considering signals other than the desired signal to be received as interfering signals, the receiving frequency amplifier contains many interfering signals in addition to the desired receiving signal, and if there is a large interfering signal within the band of the receiving frequency amplifier, the lfr If the desired signal is too small, the automatic gain adjuster of this receiving frequency amplifier will operate. Therefore, if the desired signal is sufficiently large, there is no problem, but if it is small, the #''i desired signal is not amplified by the receiving frequency amplifier, and a problem of desensitization occurs in which the receiving sensitivity is lower than when there is no interfering signal. do.
本発明は上記の従来の店受信機の問題を解決するもので
、妨害信号Ｋよる希望信号のＩＳｐｊ抑圧の改養１ｋ図
ることのできる店受信機を提供することを目的とするも
のである。The present invention solves the problems of the conventional store receiver described above, and aims to provide a store receiver capable of improving ISpj suppression of the desired signal by the interference signal K.
課ａｔ解決するための手段
上記問題を解決するために、本発明の店受信層は、受信
周波増幅器の減衰量と中間周波増幅器の減衰量を検出す
る検出器を設け、その出力信号出力により増幅度補正回
路を用いて中間周波増幅器の最大増ｌＩＩ１！度を変化
させるように構成したものである．
作用
上紀構成により、検出器に第１の自動利得調整器と第２
の自動利得調整器の出力信号から受信周波増幅器と中間
周波増幅器のそれぞれの減衰量を検出して、妨害信号に
よる減衰か、希望信号による減衰かを判別し、妨害信号
による受信周波増幅器の減衰艦の増大を、増幅度補正回
路を用いて中間局波増ｇ器の最大増幅度を大きくしてや
ることにより補正し、全体として増幅度を適正にし、妨
害信号による感度抑圧の改善を行う。Means for Solving the Problems In order to solve the above problems, the reception layer of the present invention is provided with a detector that detects the attenuation of the reception frequency amplifier and the attenuation of the intermediate frequency amplifier, and the output signal is used to amplify the signal. Maximum increase of intermediate frequency amplifier using frequency correction circuit lII1! It is constructed so that the degree of change can be changed. Due to the working configuration, the detector has a first automatic gain adjuster and a second automatic gain adjuster.
The amount of attenuation of the receiving frequency amplifier and the intermediate frequency amplifier is detected from the output signal of the automatic gain adjuster, and it is determined whether the attenuation is due to the interfering signal or the desired signal. This increase is corrected by increasing the maximum amplification of the intermediate frequency intensifier using an amplification correction circuit, the amplification is made appropriate as a whole, and sensitivity suppression due to interference signals is improved.
実施例
以下、本発明の一実施例を図面に基づいて説明する．
第１図は本発明の一実施例の涸受信機の要部グロック図
である．第１図において，ｌ．２．３．４．５．６およ
び７は従来の実施例と同じであり、その詳細な゛睨明は
省略する。受信周波増幅器２の自動利得調整器６の出力
と、中間周波増幅器４の自動利得調整器７の出力はそ几
ぞれの増幅器２．４０減衰ｔｔ決めており、検出器８＃
−ｔこれらの減衰ｉｌｋ１ｋ検出し、この減衰ｍｔ−決
める出力信号を利用して妨害信号による減衰か、希望信
号による減衰かを判別する。希望信号による減衰の場合
は、前述のように受官周波増幅器２の自動利得調整器６
の作動する最小の入力信号の大きさの方が、中間周数増
幅器４の自動利得調整器７の作動する最小の入力信号の
大きさより大きいため、自動利得！
調整器６が乍動しているとは、常に自動利得調整Ａ
ざｇ７に作動している．しかし、妨害信号による減衰の
場合は、受信周波Ｊｌｗ幅器２の自動利得調整器６け動
作しており、受信周波増幅器２の増幅度は小さくなって
いるが、中間周波増幅器４の自動利得調整器７けＩｌｌ
ｌ作していない．これは受信周波増繻器２の帯域に比べ
、中間周波増幅器４に入る信号は周波数変換器３などを
通るため帯域が狭くなっているためである。このことを
検出器８で検出し、増幅度補正回路９ｔ−順布させ、妨
害信号による受信周波増ｇｐＩＡ器の減衰社の増大全、
中間周波増幅＃４の最大増幅度を大きくしてやることに
より補正し、系全体の増幅度を妨害信号のないときの適
正な状態に近づけ、妨害信号による感度低下を防止する
．
発明の効果
以上のように、本発明の盾受信機によれば、妨害信号に
よる受信局波増幅器の減衰量の増大の影響をなくシ、感
度低下を防止できる。EXAMPLE Hereinafter, an example of the present invention will be explained based on the drawings. FIG. 1 is a Glock diagram of the main parts of a depletion receiver according to an embodiment of the present invention. In FIG. 1, l. 2.3.4.5.6 and 7 are the same as the conventional embodiment, and detailed explanation thereof will be omitted. The output of the automatic gain adjuster 6 of the reception frequency amplifier 2 and the output of the automatic gain adjuster 7 of the intermediate frequency amplifier 4 are determined by the attenuation tt of each amplifier 2.40, and
-t These attenuations ilk1k are detected, and the attenuation mt-determined output signal is used to determine whether the attenuation is due to the interference signal or the desired signal. In the case of attenuation due to the desired signal, the automatic gain adjuster 6 of the received frequency amplifier 2 is used as described above.
Since the magnitude of the minimum input signal at which the automatic gain adjuster 7 of the intermediate frequency amplifier 4 operates is greater than the magnitude of the minimum input signal at which the automatic gain adjuster 7 of the intermediate frequency amplifier 4 operates, the automatic gain! When the adjuster 6 is not working, it means that the automatic gain adjustment is always working. However, in the case of attenuation due to interference signals, six automatic gain adjusters of the receiving frequency amplifier 2 are operating, and the amplification degree of the receiving frequency amplifier 2 is small, but the automatic gain adjustment of the intermediate frequency amplifier 4 is in operation. 7 pieces Ill
I haven't made any. This is because the band of the signal entering the intermediate frequency amplifier 4 is narrower than that of the reception frequency enhancer 2 because it passes through the frequency converter 3 and the like. This is detected by the detector 8, and the amplification correction circuit 9t is applied to increase the reception frequency due to the interference signal and increase the attenuation of the GPIA device.
This is corrected by increasing the maximum amplification degree of intermediate frequency amplification #4, bringing the amplification degree of the entire system closer to the appropriate state when there is no interfering signal, and preventing a decrease in sensitivity due to the interfering signal. Effects of the Invention As described above, according to the shield receiver of the present invention, it is possible to eliminate the influence of an increase in the amount of attenuation of the receiving station wave amplifier due to an interfering signal, and to prevent a decrease in sensitivity.
第１図は本発明の一蓑施例のＡＭ９信機の要部プｐツク
図、第２図は従来例の店受信横の要部ブロック図である
．
１・・・アンテナ、２・・・受信周波増幅器、３・・・
周波数変換器、４・・・中間周波増幅器、５・・・検波
器、６．７・・・自動利得調整器、８・・・検出器、９
・・・増幅度補正回路。
第
／
図
第２図
Δ
７Fig. 1 is a block diagram of the main parts of an AM9 transmitter according to an embodiment of the present invention, and Fig. 2 is a block diagram of the main parts next to the store reception of a conventional example. 1... Antenna, 2... Receiving frequency amplifier, 3...
Frequency converter, 4... Intermediate frequency amplifier, 5... Detector, 6.7... Automatic gain adjuster, 8... Detector, 9
...Amplification correction circuit. Figure 2 Δ 7
Claims (1)
器と、前記受信周波増幅器の出力信号を中間周波信号に
変換する周波数変換器と、周波数変換した中間周波信号
を増幅する中間周波増幅器と、前記受信周波増幅器の出
力信号の強弱により前記受信周波増幅器の減衰量を変化
させる第１の自動利得調整器と、前記中間周波増幅器の
出力信号の強弱により前記中間周波増幅器の減衰量を変
化させる第２の自動利得調整器と、前記受信周波増幅器
の減衰量と前記中間周波増幅器の減衰量を検出する検出
器と、前記検出器の出力により前記中間周波増幅器の増
幅度を変化させる増幅度補正回路とを備えたＡＭ受信機
。1. A reception frequency amplifier that amplifies a signal received from an antenna, a frequency converter that converts the output signal of the reception frequency amplifier into an intermediate frequency signal, an intermediate frequency amplifier that amplifies the frequency-converted intermediate frequency signal, and the reception a first automatic gain adjuster that changes the amount of attenuation of the receiving frequency amplifier depending on the strength of the output signal of the frequency amplifier; and a second automatic gain adjuster that changes the amount of attenuation of the intermediate frequency amplifier depending on the strength of the output signal of the intermediate frequency amplifier. an automatic gain adjuster; a detector that detects the attenuation of the reception frequency amplifier and the attenuation of the intermediate frequency amplifier; and an amplification correction circuit that changes the amplification of the intermediate frequency amplifier based on the output of the detector. Equipped with an AM receiver.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009921A JPH03214928A (en) | 1990-01-19 | 1990-01-19 | AM receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009921A JPH03214928A (en) | 1990-01-19 | 1990-01-19 | AM receiver |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03214928A true JPH03214928A (en) | 1991-09-20 |
Family
ID=11733557
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2009921A Pending JPH03214928A (en) | 1990-01-19 | 1990-01-19 | AM receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03214928A (en) |
-
1990
- 1990-01-19 JP JP2009921A patent/JPH03214928A/en active Pending
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