JPS6083427A - Automatic sensitivity switching device - Google Patents

Automatic sensitivity switching device

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Publication number
JPS6083427A
JPS6083427A JP19112183A JP19112183A JPS6083427A JP S6083427 A JPS6083427 A JP S6083427A JP 19112183 A JP19112183 A JP 19112183A JP 19112183 A JP19112183 A JP 19112183A JP S6083427 A JPS6083427 A JP S6083427A
Authority
JP
Japan
Prior art keywords
level
output
sensitivity
frequency stage
circuit
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.)
Granted
Application number
JP19112183A
Other languages
Japanese (ja)
Other versions
JPH0317254B2 (en
Inventor
Hisashi Arita
有田 寿志
Kiyotake Fukui
清健 福井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP19112183A priority Critical patent/JPS6083427A/en
Publication of JPS6083427A publication Critical patent/JPS6083427A/en
Publication of JPH0317254B2 publication Critical patent/JPH0317254B2/ja
Granted legal-status Critical Current

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Abstract

PURPOSE:To eliminate the judging of sensitivity switching and the trouble of operation and perform the sensitivity switching according to a change in radio wave condition by providing a high frequency stage, intermediate frequency stage, two level detecting circuits, switching decision circuit, and sensitivity switch circuit. CONSTITUTION:A signal from an antenna 1 is inputted to the sensitivity switch circuit 2 and further outputted to the high frequency stage 3. The signal from the high frequency stage 3 is inputted to the intermediate frequency stage 4. The output of the intermediate frequency stage 4 is inputted to a level detector 11 partially and its output beta is compared with a reference level by a comparator 13. The signal inputted to said intermediate frequency stage 4 is passed through several stages of combinations of IF filters 9 and IF amplifiers 10 to lead out only a desired wave, which is outputted to a detector 12. The output of the intermediate frequency stage 4, on the other hand, is inputted to a level detector 12 to detect the level of the desired wave, which is outputted to a comparator 14. The output after compared with reference levels by comparators 13 and 14 is supplied to the switching decision circuit 15 to decide on whether a disturbance is caused or not and on the level of the desired wave, thereby outputting a signal indicating which sensitivity of the circuit is signified.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、受信機の入力感度の切換えなどに用いられる
感度自動切換装置に関する趣のである。
DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an automatic sensitivity switching device used for switching the input sensitivity of a receiver.

従来例の構成とその問題点 近年、放送局の多局化あるいはアマチーア無線局等の増
加が進んでおり、電波間の妨害によるオ旧互変調などの
問題が生じてきている。この妨害特性を改善するために
高周波段の選択度を上げたり、あるいはアッテネータな
どを用いて妨害電波の信号レベルを下げるなどの処理か
なされている。
Conventional configurations and their problems In recent years, with the increasing number of broadcasting stations and the number of Amateur radio stations, problems such as intermodulation due to interference between radio waves have arisen. In order to improve this interference characteristic, processes such as increasing the selectivity of the high frequency stage or lowering the signal level of the interference radio waves by using an attenuator or the like are carried out.

以下図面を参照しながら従来の感度切換装置について説
明する。第1図は従来の感度切換装置のブロック図であ
る。1はアンテナ、21は感度切換回路であり、高感度
高周波回路2a(す、工高感度RFという)か低感度高
周波回路2b(I21、下(1(/l&度RFという)
かの切換えを行ない高周波増1’ff1j R汁7(以
下RF増幅器という)に接続される。RF増幅器7の出
力はコンバーク8て中間周波数に変換されて中間周波段
へ出力される。
A conventional sensitivity switching device will be described below with reference to the drawings. FIG. 1 is a block diagram of a conventional sensitivity switching device. 1 is an antenna, and 21 is a sensitivity switching circuit, which is either a high-sensitivity high-frequency circuit 2a (referred to as high-sensitivity RF) or a low-sensitivity high-frequency circuit 2b (I21, lower (1 (referred to as /l & degree RF)).
After performing this switching, the high frequency amplifier 1'ff1j is connected to the R amplifier 7 (hereinafter referred to as an RF amplifier). The output of the RF amplifier 7 is converted into an intermediate frequency by a converter 8 and output to an intermediate frequency stage.

以上のような構成からなり、希望波のみであれば高感度
RF2aの出力をRF増幅器7に人ノJ1″るように感
度切換制御が行われる。
With the configuration as described above, sensitivity switching control is performed so that the output of the high-sensitivity RF2a is sent to the RF amplifier 7 when only the desired wave is present.

又、妨害波が存在する場合には低感度RF2bの出力を
RF増幅器7に入力するように感度切換制御が行われる
。ここで、感度切換制御は操作者が再生音を聞いて妨害
の有無を判断してスイッチ2bを0N10FF させる
ことにより行っている。□しかしながら、上記のような
構成においては放送局を選局するたびに妨害が生じてい
るかどうかを耳−で判断したり、あるいは同調周波数の
近傍に信号が存在するかどうかを確認した後スイッチを
操作することにより感度切換えを行なうというわずられ
しいものであり、さらに、カーラジオのように移動受信
の場合、電波状況が変化し、その都度、感度切換制御の
判断をしなければならないという問題点を有していた。
Furthermore, when interference waves are present, sensitivity switching control is performed so that the output of the low-sensitivity RF 2b is input to the RF amplifier 7. Here, the sensitivity switching control is performed by the operator listening to the reproduced sound, determining the presence or absence of interference, and turning the switch 2b to 0N10FF. □However, in the above configuration, each time you select a broadcasting station, you have to judge by ear whether or not there is interference, or check whether there is a signal near the tuned frequency before turning the switch. It is a cumbersome thing to switch the sensitivity by operating it, and furthermore, in the case of mobile reception such as a car radio, there is a problem that the radio wave condition changes and the sensitivity switching control has to be judged each time. It had a point.

発明の目的 本発明は、感度切換えの判断および操作のわずられしさ
をなくすとともに、電波状況の変化に応じて感P切換え
を行ない、妨害波による影響を少なくしながら、高感度
を維持することを可能にする感度自動切換装置を提供す
るを目的とする。
Purpose of the Invention The present invention eliminates the troublesome judgment and operation of sensitivity switching, and also maintains high sensitivity while reducing the influence of interference waves by switching sensitivity P in response to changes in radio wave conditions. The purpose of the present invention is to provide an automatic sensitivity switching device that enables this.

発明の構成 本発明の感度自動切換装置は、高周波段と、前記高周波
段(コンバータを含む)の出力レベルを検出する第1の
レベル検出回路と、中間周波段と、:晶記中間周波段の
□出力レベルを検出する第2のレベル検出回路と、上記
第1のレベル検出回路の出力と基準レベルを比較する第
1の比較器と、上記第2のレベル検出、回路、の出力−
と基糸レベルを比較する第2の比較器と、上記第1.第
2の比較器の出力に基づき感度切換の判定を行う切換判
定回路と、I)iJ記切換判定回路の出力に基づき人力
感度を少なくとも2段以」二切換える感度切換回路から
構成したものであり、これにより希望波と妨害波の受信
レベルに応じて自動的に感度設定を行なうものである。
Structure of the Invention The automatic sensitivity switching device of the present invention comprises: a high frequency stage; a first level detection circuit for detecting the output level of the high frequency stage (including a converter); an intermediate frequency stage; □A second level detection circuit that detects the output level, a first comparator that compares the output of the first level detection circuit with a reference level, and the output of the second level detection circuit.
and a second comparator that compares the base thread level with the first one. It consists of a switching determination circuit that determines sensitivity switching based on the output of the second comparator, and a sensitivity switching circuit that switches the human sensitivity by at least two steps or more based on the output of the switching determination circuit described in I). , thereby automatically setting the sensitivity according to the reception levels of the desired wave and the interference wave.

実施例の説明 以下本発明の一実施例について図面を参照しながら説明
する。
DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

第2図は本発明の一実施例における感度自動切換装置の
ブロック図であり、第1図のブロック図と同一の部分に
ついては、同一番号を付している。
FIG. 2 is a block diagram of an automatic sensitivity switching device according to an embodiment of the present invention, and the same parts as in the block diagram of FIG. 1 are given the same numbers.

第2図において、アンテナ1がら入力された信号tri
感度切換回路2に入力される。さらに大刀信号は感度切
換回路2(後述のように少なくとも2段以上用意された
感度のいずれがが設定される)を経て高□周波段3に出
力される。ここで、感度切換手段としてアッテネータを
用いた場合を示してあり、第1.第2.第3LT)T 
ソテネータ5 b 、 6 c。
In FIG. 2, the signal tri input from antenna 1
The signal is input to the sensitivity switching circuit 2. Further, the long sword signal is outputted to the high frequency stage 3 via a sensitivity switching circuit 2 (which one of at least two or more stages of sensitivity is set as described later). Here, a case is shown in which an attenuator is used as the sensitivity switching means. Second. 3rd LT)T
Sotenators 5b, 6c.

5dはそれぞれ異なるアッテネータ量を有している。今
、仮に、アッテネータはATTn(n=1−3 )のn
が大きいほど、大きいものとする。高周波段3の同調回
路6で希望信号が選択され高周波増幅器(以下RF増幅
器)7に入力される。RF増幅器7は利得制御ができる
場合を示してあり、RF増幅器7の出力はコンバータ8
で中間周波数に変換されて中間周波段4に入力される。
5d have different attenuator amounts. Now, suppose the attenuator is n of ATTn (n=1-3)
The larger the value, the larger the value. A desired signal is selected by a tuning circuit 6 of the high frequency stage 3 and inputted to a high frequency amplifier (hereinafter referred to as an RF amplifier) 7. The case where the RF amplifier 7 can control the gain is shown, and the output of the RF amplifier 7 is connected to the converter 8.
The signal is converted into an intermediate frequency and input to the intermediate frequency stage 4.

又、コンバータ8の出力はレベル検出器11に入力され
、高周波段3の出力レベルが検出される。レベル検出器
11の出力βは、比較器13に入力され、基準レベルと
の比較がなされる。レベル検出器11のも、う一方の出
力β′はRF増幅器7の利得制御にも使用される。一般
に、RF増幅器7とレベル検出器11で構成される回路
を自動利得制御回路(ACiC回路)と呼び、AGC回
路の制御電圧として、高周波段3の出力レベルを検出し
たものを用いた場合を示しである。又、中間周波段4に
入力された信号は、中間周波フィルタ9(IFフィルタ
)と中間周波振幅制限増幅器1Q(工F増幅器)の組み
合せを数段通り、希望波のみが取り出されて中間周波段
4より検波器に出力される。一方、中間周波段4の出力
は、レベル検出器12に入力され希望波のレベルを検出
して比較器14に出力される。比較器13.14で基糸
レベルと比較された出力は切換判定回路15で妨害の有
無、礼望波のレベル等の判定を行ない、感度切換回路2
のいずれの感度に設定するかの信号を出力する。
Further, the output of the converter 8 is input to a level detector 11, and the output level of the high frequency stage 3 is detected. The output β of the level detector 11 is input to a comparator 13 and compared with a reference level. The other output β' of the level detector 11 is also used for gain control of the RF amplifier 7. Generally, the circuit composed of the RF amplifier 7 and the level detector 11 is called an automatic gain control circuit (ACiC circuit), and the case where the detected output level of the high frequency stage 3 is used as the control voltage of the AGC circuit is shown. It is. In addition, the signal input to the intermediate frequency stage 4 passes through several stages of combinations of an intermediate frequency filter 9 (IF filter) and an intermediate frequency amplitude limiting amplifier 1Q (factor amplifier), and only the desired wave is extracted and sent to the intermediate frequency stage. 4 to the detector. On the other hand, the output of the intermediate frequency stage 4 is input to a level detector 12 to detect the level of the desired wave and output to a comparator 14. The output compared with the base thread level by the comparators 13 and 14 is sent to the switching judgment circuit 15 to judge the presence or absence of interference, the level of the signal wave, etc., and then sent to the sensitivity switching circuit 2.
Outputs a signal indicating which sensitivity to set.

第3図に、高周波段3と中間周波段4の周波数選択度特
性を示す。
FIG. 3 shows the frequency selectivity characteristics of the high frequency stage 3 and the intermediate frequency stage 4.

ここで、中心周波数fcは中間周波数であり、±faの
周波数帯域を有するのは中間周波段4の出力であり、±
fbの周波数帯域を有するのは高周波段3の出力である
。中間周波段4の出力の周波数帯域はIFフィルタ9で
決まり、高周波段3の出力の周波数帯域は、同調回路6
の選択度で決する。一般にFM受信機の場合faはfc
に対して±50 dlz 〜土110kll+で、fB
は±800i〜±1.5111iである。
Here, the center frequency fc is an intermediate frequency, and it is the output of the intermediate frequency stage 4 that has a frequency band of ±fa, and ±
It is the output of the high frequency stage 3 that has the frequency band fb. The frequency band of the output of the intermediate frequency stage 4 is determined by the IF filter 9, and the frequency band of the output of the high frequency stage 3 is determined by the tuning circuit 6.
It is determined by the selectivity of Generally, in the case of an FM receiver, fa is fc
±50 dlz to Sat 110kll+, fB
is ±800i to ±1.5111i.

以上のように構成された本実施例の感度自動切換装置に
ついて、以下にその動作を説明する。
The operation of the automatic sensitivity switching device of this embodiment configured as described above will be described below.

第4図は、希望波のみの場合の入力レベルとレベル検出
器11の出力β(一点鎖線)と、レベル検出器12の出
力α(実線)との関係を示す図である。第4図において
、入力信号レベルがγ2になるまでは出力αは入力レベ
ルの増加と共に増加し、出力βは出力されない。入力レ
ベルが12以上になると、出力βはRF増幅器7の出力
レベルの増加を押えるように、入力レベルの増加に伴っ
て増加する。一方、中間周波段4の入力がAGC回路の
働きにより、一定レベルに近くなると同時に、IF増幅
器1oの振幅制限機能の為に出力αは一定となる。
FIG. 4 is a diagram showing the relationship between the input level, the output β (dotted chain line) of the level detector 11, and the output α (solid line) of the level detector 12 in the case of only the desired wave. In FIG. 4, the output α increases as the input level increases and the output β is not output until the input signal level reaches γ2. When the input level becomes 12 or more, the output β increases as the input level increases so as to suppress the increase in the output level of the RF amplifier 7. On the other hand, when the input to the intermediate frequency stage 4 approaches a constant level due to the action of the AGC circuit, the output α becomes constant due to the amplitude limiting function of the IF amplifier 1o.

第6図は、第4図における出力αと出力βの関係を示し
たもので、実線Xが希望波のみの場合の関係を示してい
る。
FIG. 6 shows the relationship between the output α and the output β in FIG. 4, and the solid line X shows the relationship when there is only the desired wave.

第6図(イ)は、希望波fDと妨害波fuが存在する場
合を示しており、希望波fDの信号レベルが妨害波fu
の信号レベルより太きけれはα、βの関係は第6図(ロ
)の一点鎖線X1となるが、妨害波fuの信ぞレベルが
希望波fDの信号レベルは大きくなると、出力α、βの
関係はX“でなくなる。今仮りに、希望波fDの入力レ
ベルがγ2とし、妨害波fuの入力レベルがγ2より大
きいとすると出力βは妨害波fuの増加に従って増加し
ていく。
Figure 6 (a) shows a case where there is a desired wave fD and an interference wave fu, and the signal level of the desired wave fD is higher than the interference wave fu.
If the deviation is thicker than the signal level of , the relationship between α and β is as shown by the dashed-dotted line The relationship is no longer X''. Now, if the input level of the desired wave fD is γ2 and the input level of the interference wave fu is greater than γ2, the output β will increase as the interference wave fu increases.

この時、出力βの増加によりRF増幅器7は妨害波fu
のレベルを一定に保つように働く。この為、等側内に希
望波fDのレベルが下げられることにより、出力αは減
少していく。この時の出力α。
At this time, due to the increase in the output β, the RF amplifier 7 generates an interference wave fu.
works to maintain a constant level. Therefore, as the level of the desired wave fD is lowered on the equal side, the output α decreases. Output α at this time.

βの関係を第6図(ロ)のγ;で示す。The relationship between β is shown by γ in FIG. 6 (b).

妨害波fuの入力レベルが増加するに従って、γ′2の
矢印の方向に関係が移っていく。以下、希望波fDの入
力レベルがγ1の時、妨害波fuが増加するに従いγ4
の矢印の関係へと移っていき、同様に希望波fDの入力
レベルがr3の時はγ′3の矢印の関係へと移っていく
As the input level of the interference wave fu increases, the relationship shifts in the direction of the arrow γ'2. Below, when the input level of the desired wave fD is γ1, as the interference wave fu increases, γ4
Similarly, when the input level of the desired wave fD is r3, the relationship shifts to the relationship indicated by the arrow γ'3.

以上より、出力α、βの関係を使って妨害の有無を検出
する事が出来る。第7図(イ)において、比較器13の
基準レベルをYβ1 とYβ2、比較器13 、1.4
からは後述するように°’H”(ハイレベル)あるいは
”L ” (ローレベル)が出方されるように設定する
。この基準レベルYβ1.Yβ2゜Yal、Yct2 
の設定により、出力α、βの関係は9個の領域に分けら
れる。第7図(ロ)に比較器13゜14の出力関係を示
す。同図において、■の領域の比較器13.14の出力
を’ L HL H”としているが、これを” LlH
l L2H2”と書きなおすと、Ll、Hlは比較器1
3の出力で、L2゜H2は比較器14の出方である。そ
して、Llは基準レベルYβ2.H1は基県レベルYβ
1のそれぞれ出力βと比較した時の比較器13の出力で
あり、L2は基準レベルYLO12,H2は基準レベル
Y。1のそれぞれと出力αと比較した時の比較器14の
出力を示している。ここでは、基桑レベルよりレベル検
出器11.12の出方が大きい場合” H”が出力され
る場合を示している。希望信号のみであれば、入力レベ
ルが大きくなるにつれて比較器13.14の出力状態は
■→■→@→■→■という出力が得られる。一方、妨害
が存在する場合は、@、■、@、■の領域に含まれる事
になる。
From the above, the presence or absence of interference can be detected using the relationship between the outputs α and β. In FIG. 7(a), the reference levels of the comparator 13 are Yβ1 and Yβ2, and the comparator 13 is 1.4.
As described later, the setting is made so that °'H" (high level) or "L" (low level) is output. This reference level Yβ1.Yβ2゜Yal, Yct2
According to the settings, the relationship between the outputs α and β can be divided into nine regions. FIG. 7(b) shows the output relationship of the comparators 13 and 14. In the figure, the outputs of the comparators 13 and 14 in the area ■ are shown as ``L HL H'', but this is ``LlH''.
l L2H2”, Ll and Hl are comparator 1
3, L2°H2 is the output of the comparator 14. And Ll is the reference level Yβ2. H1 is the base prefecture level Yβ
1. L2 is the reference level YLO12, and H2 is the reference level Y. 1 and the output α of the comparator 14 are shown. Here, a case is shown in which "H" is output when the output of the level detectors 11 and 12 is higher than the base level. If only the desired signal is present, as the input level increases, the output state of the comparators 13 and 14 becomes ■→■→@→■→■. On the other hand, if interference exists, it will be included in the @, ■, @, ■ areas.

次に切換判定回路16の動作として、比較器13.14
の出力に基づき一例を説明する。まず、希望波のみの場
合で、大きなレベルの場合は■にあることより、アッテ
ネータ量を多くするブT向に感度切換回路2に指示を与
え、スイッチの接点をAn−+An、−1(○≦n (
n +1≦3)と順次切換え■の領域に含まれた時点で
、感度切換動作を止める。一方、入力レベルが小さくな
った場合っ寸り、■、■のような領域に金回れる場合、
感度切換回路2に指示を与え、スイッチの接点をAn→
An−1(○≦n−1(n≦3)と順次切換え@あるい
は@の領域に含丑れた時点で、感度切換動作を止める。
Next, as the operation of the switching determination circuit 16, the comparators 13 and 14
An example will be explained based on the output of . First, when there is only the desired wave and the level is large, from the point in ■ ≦n (
n+1≦3), and the sensitivity switching operation is stopped when the sensitivity is included in the sequential switching region (■). On the other hand, if the input level becomes small and the input level becomes small, it can move into the areas like ■ and ■,
Give an instruction to the sensitivity switching circuit 2 and change the switch contact to An→
An-1 (◯≦n-1 (n≦3)), and the sensitivity switching operation is stopped when the sensitivity changes in the @ or @ region.

次に妨害波が存在する場合、@■@■の領域にあること
より、■■@■■の領域に含まれるように、感度切換回
路2に切換判定回路15より指示を与え、スイッチ接点
An−+An+1(○≦n (n + 1≦3)と順次
切換える。そして、■■@■■の領域に含まれた時点に
おいては、希望波のみの場合の制御に従う。以上に簡単
な動作を説明したが、比較器13.14の持つ基準レベ
ルの数や、感度切換回路2の有するアッテネータの数お
よび、切換判定回路16の動作アルゴリズム等により、
さらに最適の制御がなされる。又、切換判定回路として
、PLLシンセサイザ一方式の受信機等では、マイクロ
コンビーータ(マイコン)を有している事より、切換判
定回路15の動作をマイコンにて行なわせることも出来
る。さらに、感度切換回路として第2図の実施例ではア
ッテネータを使用したが、他の方法として妨害が無い場
合あるいは希望波の入力レベルが大きくない場合にはR
F増幅器で増幅してコンバータに人力し、妨害が存在す
る場合あるいは、希望波の入力レベルが非常に大きな場
合には非直線性を有するRF増幅器を通さずに直接コン
バータに入力するという方法によっても、感度切換と同
等の効果が得られる。
Next, when there is an interference wave, since it is in the area of @■@■, the switching determination circuit 15 gives an instruction to the sensitivity switching circuit 2 so that it is included in the area of ■■@■■, and the switch contact An −+An+1 (○≦n (n + 1≦3)). Then, at the point in time when it is included in the region of ■■@■■, the control in the case of only the desired wave is followed.The simple operation is explained above. However, depending on the number of reference levels of the comparators 13 and 14, the number of attenuators of the sensitivity switching circuit 2, the operation algorithm of the switching judgment circuit 16, etc.
Furthermore, optimal control is achieved. Further, since a PLL synthesizer type receiver or the like has a microcomputer as a switching determination circuit, the operation of the switching determination circuit 15 can be performed by the microcomputer. Furthermore, although an attenuator is used as a sensitivity switching circuit in the embodiment shown in Fig. 2, other methods can be used when there is no interference or when the input level of the desired wave is not large.
If there is interference or the input level of the desired wave is very large, it can be amplified by an F amplifier and input directly to the converter without passing through the RF amplifier, which has non-linearity. , the same effect as sensitivity switching can be obtained.

発明の効果 以上の説明から明らかなように、本発明は妨害波が存在
し相互変調妨害を発生させる可能性が有る場合には、感
度を低下させてその影響を軽減するとともに、妨害波レ
ベルが下れはもとの状態に自動的に復帰し、電波状況に
追随した動作を自動的に行ない、妨害波による歪の軽減
を行なうというすぐれた効果が得られる。
Effects of the Invention As is clear from the above explanation, the present invention reduces the sensitivity to reduce the effect when interference waves exist and may cause intermodulation interference, and also reduces the interference wave level. When the system goes down, it automatically returns to its original state, automatically performs operations that follow the radio wave conditions, and has the excellent effect of reducing distortion caused by interfering waves.

さらに、希望波の入力レベルが非常に大きく歪が発生す
る場合においても、自動的に感度を低下させて歪を軽減
する効果が得られる。したがって、従来のように操作者
が再生音の良否により判断して感度切換えを行なうとい
うわずられしさをなくすことができる。
Furthermore, even when the input level of the desired wave is very high and distortion occurs, the effect of automatically lowering the sensitivity and reducing the distortion can be obtained. Therefore, it is possible to eliminate the hassle of the operator having to switch the sensitivity based on the quality of the reproduced sound as in the prior art.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は従来の感度切換装置のブロック図、第2図は本
発明の一実施例における感度切換装置のブロック図、第
3図は同装置における高周波段と中間周波段の出力信号
の有する周波数選択度特性図、第4図は同装置における
希望波のみの場合の人力レベルとレベル検出器出方、と
の関係を示す図、第5図は同装置における高周波段と中
間周波段のそれぞれに接続されているレベル検出器出方
の相互関係図、第6図(イ)は同装置における希望波と
妨害波の周波数関係図、第6図(0)は同装置における
妨害波が存在する場合のレベル検出器の出方関係は1、
第7図(イ)は同装置における比較器の基準レベル図、
第7図(ロ)は同装置におけ、る比較器の基準レベルに
より分割された領域におけるそれぞれの比較器出力の状
態図である。 2.2′・・・・・・感度切換回路、3・・す・−高周
波段、4・・・中間周波段、11.12・・・・・レベ
ル検出器、13.14・・・・・比較器、15・・川・
切換判定回路、代理人の氏名 弁理士 中 尾 敏 男
 ほか1名第5図 rta、hβht3 レベル検出遍、ニオρ 第6図 (イ) LfD 用仮数 rF) rfB、r2/3 /s/3 レペ°ル枝土器出力β 第7図 (イ9 ;1st yβ2 しNル卆た土着出力β 第7図 (゛ロノ ↑ レヘル抄出X出カρ 手続補正書(自発) 1事件の表示 昭和58年特許願第191j21 号 2発明の名称 感度自動切換装置 3補正をする者 事件との関係 特 許 出 願 人 任 所 大阪府門真市大字門真1006番地名 称 (
582)松下電器産業株式会社代表者 山 下 俊 彦 4代理人 〒571 住 所 大阪j(」門真市大字門真1006番地松下電
器産業株式会社内 5補正の対象 6、補正の内容 (1)明細書第3頁第5行目の「2b」を「2C」に補
正します。 (2)同第8頁第9行目の「信号レベルは」を「信号レ
ベルより」に補正します0 (3)同第9頁第7行目の「比較器」を「比較器14の
基準レベルをYα+、Yα2とし、比較器」に補正しま
ず。 (4)図面の第1図を別紙の通り補正し捷す。
FIG. 1 is a block diagram of a conventional sensitivity switching device, FIG. 2 is a block diagram of a sensitivity switching device according to an embodiment of the present invention, and FIG. 3 is a frequency diagram of the output signals of the high frequency stage and intermediate frequency stage in the same device. Selectivity characteristic diagram, Figure 4 is a diagram showing the relationship between the human power level and the level detector output in the case of only the desired wave in the same device, and Figure 5 is a diagram showing the relationship between the output level of the level detector in the case of only the desired wave in the same device, and Figure 5 is a diagram showing the relationship between the output level of the level detector and the high frequency stage in the same device. Figure 6 (a) is a diagram of the relationship between the outputs of the connected level detectors, and Figure 6 (a) is a diagram of the frequency relationship between the desired wave and interference wave in the same device, and Figure 6 (0) is the case where interference waves exist in the same device. The output relationship of the level detector is 1,
Figure 7 (a) is a reference level diagram of the comparator in the same device.
FIG. 7(B) is a state diagram of the output of each comparator in the region divided by the reference level of the comparator in the same device. 2.2'... Sensitivity switching circuit, 3... High frequency stage, 4... Intermediate frequency stage, 11.12... Level detector, 13.14...・Comparator, 15・・River・
Switching judgment circuit, name of agent Patent attorney Toshio Nakao and one other person Figure 5 rta, hβht3 Level detection range, ρ Figure 6 (a) Mantissa for LfD rF) rfB, r2/3 /s/3 Pel branch earthenware output β Fig. 7 (A9; 1st yβ2 and N Ru's indigenous output β Fig. 7 (゛rono↑ Lehel extraction Patent Application No. 191j21 2 Name of Invention Automatic Sensitivity Switching Device 3 Relationship with the Amendment Case Patent Application Person Address 1006 Kadoma, Kadoma City, Osaka Prefecture Name (
582) Matsushita Electric Industrial Co., Ltd. Representative Toshihiko Yamashita 4 Agent 571 Address Osaka J ('1006 Oaza Kadoma, Kadoma City Matsushita Electric Industrial Co., Ltd. 5 Subject of amendment 6, Contents of amendment (1) Specification Correct “2b” on the 5th line of the 3rd page to “2C”. (2) Correct “The signal level is” on the 9th line of the 8th page of the same page to “from the signal level” 0 (3 ) First, correct "Comparator" in the 7th line of page 9 to "Comparator with the reference level of comparator 14 set as Yα+ and Yα2." (4) Correct Figure 1 of the drawing as shown in the attached sheet. Sort.

Claims (1)

【特許請求の範囲】[Claims] 高周波段と、前記高周波段の出力レベルを検出する第1
のレベル検出回路と、前記高周波段に接続された中間周
波段と、前記中間周波段の出力レベルを検出する第2の
レベル検出回路と、上記第1のレベル検出回路の出力と
基準レベルを比較する第1の比較器と、上記第2のレベ
ル検出回路の出力と基準レベルを比較する第2の比較器
と、上記第1.第2の比較器の出力に基づき感度りJ換
の判定を行う切換判定回路と、前記切換判定回路の出力
に基づき入力感度を少なくとも2段以上切換える感度切
換回路とを具備し、希望波と妨害波のレベルに応じて感
度を自動的に切換えることを特徴とする感度自動切換装
置。
a high frequency stage; and a first circuit for detecting the output level of the high frequency stage.
a level detection circuit, an intermediate frequency stage connected to the high frequency stage, a second level detection circuit for detecting the output level of the intermediate frequency stage, and an output of the first level detection circuit and a reference level are compared. a first comparator that compares the output of the second level detection circuit with a reference level; A switching determination circuit that determines whether the sensitivity is to be switched based on the output of the second comparator, and a sensitivity switching circuit that switches the input sensitivity by at least two steps or more based on the output of the switching determination circuit. An automatic sensitivity switching device characterized by automatically switching sensitivity according to the wave level.
JP19112183A 1983-10-13 1983-10-13 Automatic sensitivity switching device Granted JPS6083427A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19112183A JPS6083427A (en) 1983-10-13 1983-10-13 Automatic sensitivity switching device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19112183A JPS6083427A (en) 1983-10-13 1983-10-13 Automatic sensitivity switching device

Publications (2)

Publication Number Publication Date
JPS6083427A true JPS6083427A (en) 1985-05-11
JPH0317254B2 JPH0317254B2 (en) 1991-03-07

Family

ID=16269210

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19112183A Granted JPS6083427A (en) 1983-10-13 1983-10-13 Automatic sensitivity switching device

Country Status (1)

Country Link
JP (1) JPS6083427A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5689814A (en) * 1993-08-20 1997-11-18 Hitachi, Ltd. Radio communication apparatus with expanded dynamic range
US7983293B2 (en) 2003-07-30 2011-07-19 Toyota Jidosha Kabushiki Kaisha External signal supply unit, vehicle state acquisition system and external signal supply method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5689814A (en) * 1993-08-20 1997-11-18 Hitachi, Ltd. Radio communication apparatus with expanded dynamic range
US7983293B2 (en) 2003-07-30 2011-07-19 Toyota Jidosha Kabushiki Kaisha External signal supply unit, vehicle state acquisition system and external signal supply method

Also Published As

Publication number Publication date
JPH0317254B2 (en) 1991-03-07

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