JPS60232715A - Automatic channel scanning system - Google Patents

Automatic channel scanning system

Info

Publication number
JPS60232715A
JPS60232715A JP8811984A JP8811984A JPS60232715A JP S60232715 A JPS60232715 A JP S60232715A JP 8811984 A JP8811984 A JP 8811984A JP 8811984 A JP8811984 A JP 8811984A JP S60232715 A JPS60232715 A JP S60232715A
Authority
JP
Japan
Prior art keywords
signal
low frequency
circuit
detector
channel
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
Application number
JP8811984A
Other languages
Japanese (ja)
Inventor
Yoichi Miyazaki
洋一 宮崎
Toru Akiyama
徹 秋山
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric 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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP8811984A priority Critical patent/JPS60232715A/en
Publication of JPS60232715A publication Critical patent/JPS60232715A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03JTUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J7/00Automatic frequency control; Automatic scanning over a band of frequencies
    • H03J7/18Automatic scanning over a band of frequencies

Landscapes

  • Channel Selection Circuits, Automatic Tuning Circuits (AREA)

Abstract

PURPOSE:To prevent a channel transmitting a non-modulated carrier from being selected as a communicating channel without the delay of scanning frequency by using both carrier detection and low frequency detection. CONSTITUTION:A receiving signal from an input terminal 1 is received by a channel tuning circuit 2 in an automatic channel scanning system and its output is branched and inputted to a signal demodulation circuit 3 and a carrier detector 6. A low frequency signal demodulated by the circuit is branched, one branched signal is inputted to a speaker 5 through a low frequency output circuit 4 to output a voice and the other is applied to a low frequency detector 7. A detecting signal detected by the detector 6 is applied to the low frequency detector 7 and a scan stopping circuit 8 and a non-detected signal from the detector 7 is applied to the circuit 8. If no low frequency signal is detected by the detector 7 within a fixed period, a non-detecting signal is outputted to stop a signal from the detector 6. Then, a channel scanning circuit 9 starts to scan again and all circuits are restored to normal state.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、無線通信受信機の自動チャンネルスキャン方
式に関する。特に、通話中のチャンネルの自動検出に関
するものである。
DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic channel scanning method for a wireless communication receiver. In particular, it relates to automatic detection of active channels.

〔従来の技術〕[Conventional technology]

従来の無線通信受信機の自動チャンネルスキャン方式に
は、キャリアを検出して自動選択をする方式と復調後の
低周波を検出して自動選択をする方式とがある。キャリ
ア検出方式は、キャリアの有無のみを検出し、自動選択
するため、無変調のキャリアが出力されているチャンネ
ルを通信中のチャンネルとしてする欠点があった。一方
、低周波検出方式はキャリア検出方式に比べて時間がか
かり、スキャン周期の時間が長くなる欠点があった。
Conventional automatic channel scanning methods for wireless communication receivers include a method that detects a carrier and automatically selects it, and a method that detects a low frequency after demodulation and automatically selects it. The carrier detection method detects only the presence or absence of a carrier and automatically selects it, so it has the disadvantage that a channel on which an unmodulated carrier is output is set as the channel in use. On the other hand, the low frequency detection method takes more time than the carrier detection method, and has the disadvantage that the scan period is longer.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

本発明は、スキャン周期が速く、しかも無変調波が出力
されているチャンネルを選択することがない自動チャン
ネルスキャン方式を提供すること目的とする。
SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic channel scan method that has a fast scan cycle and does not select a channel on which unmodulated waves are output.

〔問題点を解決するための手段〕[Means for solving problems]

本発明は、あらかじめ設定された複数の受信チャンネル
について自動的に順次切り換えて受信を行う手段と、そ
の受信チャンネルが使用状態であることを検出する手段
と、この検出する手段に検出出力が送出されると上記受
信を行う手段のチャンネルの自動切り換えを停止させる
手段とを備えた自動チャンネルスキャン方式において、
上記検出する手段は、受信信号のキャリアを検出する手
段と、このキャリアを検出する手段の検出出力により起
動し上記受信信号の低周波信号を検出する手段とを含み
、上記停止させる手段は、この低周波信号を検出する手
段の検出出力により上記自動切り換えを停止させるよう
に構成されたことを特徴とする。
The present invention provides means for automatically sequentially switching and receiving a plurality of reception channels set in advance, means for detecting that the reception channel is in use, and a detection output sent to the detection means. and means for stopping automatic channel switching of the means for performing the reception,
The detecting means includes means for detecting a carrier of the received signal, and means for detecting a low frequency signal of the received signal activated by the detection output of the carrier detecting means, and the stopping means includes a means for detecting a low frequency signal of the received signal. The present invention is characterized in that the automatic switching is stopped by the detection output of the means for detecting the low frequency signal.

〔作用〕[Effect]

本発明は、キャリア検出と低周波検出とを併用したとこ
ろに特徴がある。すなわち、キャリア有りにより選択さ
れたチャンネルに対して、さらに通話中の音声等の低周
波を検出して、これが検出できないと選択したチャンネ
ルを無効とし、チャンネルスキャンを再開することによ
り、スキャン周期を速くするとともに、無変調キャリア
を送信している通信中のチャンネルとして選択すること
がないようにすることができる。
The present invention is characterized by the combined use of carrier detection and low frequency detection. In other words, for the channel selected due to the presence of a carrier, low frequencies such as voice during a call are detected, and if this cannot be detected, the selected channel is invalidated and the channel scan is restarted, thereby speeding up the scanning cycle. At the same time, it is possible to avoid selecting an unmodulated carrier as a channel during communication that is transmitting it.

〔実施例〕〔Example〕

本発明の実施例について図面を参照して説明する。図は
本発明一実施例自動チャンネルスキャン装置のブロック
構成図である。−受信信号が入力する入力端子1はチャ
ンネル同調回路2に接続される。チャンネル同調回路2
の出力は信号復調回路3に接続される。信号復調回路3
から復調された低周波信号が低周波出力回路4を経由し
て拡声器5に接続され、音声として出力される。
Embodiments of the present invention will be described with reference to the drawings. The figure is a block diagram of an automatic channel scanning device according to an embodiment of the present invention. - the input terminal 1 into which the received signal is input is connected to the channel tuning circuit 2; Channel tuning circuit 2
The output of is connected to the signal demodulation circuit 3. Signal demodulation circuit 3
A low frequency signal demodulated from the low frequency signal is connected to a loudspeaker 5 via a low frequency output circuit 4 and output as audio.

ここで本発明の特徴とするところは、一点鎖線で囲まれ
るキャリア低周波検出部分である。すなわち、チャンネ
ル同調回路2の出力は分岐されてキャリア検出器6に接
続される。信号復調回路3からの低周波信号は分離され
て低周波検出器7に接続される。キャリア検出器6から
の検出信号が低周波検出器7とスキャン停止回路8とに
接続される。また、低周波検出器7からの非検出信号が
スキ式・ン停止回路8に接続される。スキャン停止回路
8からスキャン停止信号がチャンネルスキャン回路9に
接続される。チャンネルスキャン回路9からチャンネル
選択信号がチャンネル同調回路2に接続される。
Here, the feature of the present invention is the carrier low frequency detection portion surrounded by a dashed line. That is, the output of the channel tuning circuit 2 is branched and connected to the carrier detector 6. The low frequency signal from the signal demodulation circuit 3 is separated and connected to the low frequency detector 7. A detection signal from carrier detector 6 is connected to low frequency detector 7 and scan stop circuit 8. Further, a non-detection signal from the low frequency detector 7 is connected to the open/down stop circuit 8. A scan stop signal is connected from the scan stop circuit 8 to the channel scan circuit 9. A channel selection signal from the channel scan circuit 9 is connected to the channel tuning circuit 2.

このような構成の自動チャンネルスキャン装置の動作に
ついて説明する。図において、通常、チャンネル同調回
路2は、チャンネルスキャン回路9により複数のチャン
ネルをスキャンしている。
The operation of the automatic channel scanning device having such a configuration will be explained. In the figure, the channel tuning circuit 2 normally scans a plurality of channels using the channel scanning circuit 9.

いま、あるチャンネルでキャリアが検出されると、キャ
リア検出HGが働き、スキャン停止回路8を介してチャ
ンネルスキャン回路9を停止させるとともに低周波検出
器7を作動させる。低周波検出器7は、一定時間以内に
低周波が検出される場合には、信号を出力しないが、検
出されない場合には、低周波非検出信号を出力し、スキ
ャン停止回路8に作用して、キャリア検出器6からのキ
ャリア検出信号を止める。これにより、チャンネルスキ
ャン回路9は、再びスキャンを開始する。スキャン開始
により、すべての回路は最初の通常状態にもどる。
Now, when a carrier is detected in a certain channel, the carrier detection HG is activated, and the channel scan circuit 9 is stopped via the scan stop circuit 8, and the low frequency detector 7 is activated. The low frequency detector 7 does not output a signal if a low frequency is detected within a certain period of time, but if it is not detected, it outputs a low frequency non-detection signal and acts on the scan stop circuit 8. , the carrier detection signal from the carrier detector 6 is stopped. As a result, the channel scan circuit 9 starts scanning again. By starting the scan, all circuits return to their initial normal states.

〔発明の効果〕〔Effect of the invention〕

本発明は、以上説明したように、キャリア検出器、低周
波検出器およびスキャン停止回路を設け、キャリア検出
によるスキャンと、低周波検出によりスキャンとを併用
することにより、スキャン周期を遅くすることなく、無
変調キャリアを送信しているチャンネルを通信中のチャ
ンネルとして選択することをなくする優れた効果がある
As explained above, the present invention provides a carrier detector, a low frequency detector, and a scan stop circuit, and uses both scanning by carrier detection and scanning by low frequency detection, without slowing down the scan cycle. This has the excellent effect of eliminating the need to select a channel transmitting an unmodulated carrier as the channel in use.

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

図は本発明一実施例自動チャンネルスキャン装置のブロ
ック構成図。 1・・・入力端子、2・・・チャンネル同調回路、3・
・・信号復調回路、4・・・低周波出力回路、5・・・
拡声器6・・・キャリア検出器、7・・・低周波検出器
、8・・・スキャン停止回路、9・・・チャンネルスキ
ャン回路。 特許出願人 日本電気株式会社 代理人 弁理士 井 出 直 孝
The figure is a block diagram of an automatic channel scanning device according to an embodiment of the present invention. 1... Input terminal, 2... Channel tuning circuit, 3...
...Signal demodulation circuit, 4...Low frequency output circuit, 5...
Loudspeaker 6...carrier detector, 7...low frequency detector, 8...scan stop circuit, 9...channel scan circuit. Patent applicant: NEC Corporation Representative Patent attorney: Naotaka Ide

Claims (1)

【特許請求の範囲】[Claims] (1) あらかじめ設定された複数の受信チャンネルに
ついて自動的に順次切り換えて受信を行う手段と、その
受信チャンネルが使用状態であることを検出する手段と
、この検出する手段に検出出力が送出されると上記受信
を行う手段のチャンネルの自動切り換えを停止させる手
段と を備えた自動チャンネルスキャン方式において、上記検
出する手段と、 受信信号のキャリアを検出する手段と、このキャリアを
検出する手段の検出出力により起動し上記受信信号の低
周波信号を検出する手段と を含み、 上記停止させる手段は、この低周波信号を検出する手段
の検出出力により上記自動切り換えを停止させるように
構成された ことを特徴とする自動チャンネルスキャン方式。
(1) A means for automatically sequentially switching and receiving a plurality of reception channels set in advance, a means for detecting that the reception channel is in use, and a detection output is sent to the detection means. and means for stopping automatic channel switching of the means for performing reception, the means for detecting, the means for detecting the carrier of the received signal, and the detection output of the means for detecting the carrier. means for detecting a low frequency signal of the received signal, and the stopping means is configured to stop the automatic switching in response to a detection output of the means for detecting the low frequency signal. Automatic channel scanning method.
JP8811984A 1984-05-01 1984-05-01 Automatic channel scanning system Pending JPS60232715A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8811984A JPS60232715A (en) 1984-05-01 1984-05-01 Automatic channel scanning system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8811984A JPS60232715A (en) 1984-05-01 1984-05-01 Automatic channel scanning system

Publications (1)

Publication Number Publication Date
JPS60232715A true JPS60232715A (en) 1985-11-19

Family

ID=13934008

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8811984A Pending JPS60232715A (en) 1984-05-01 1984-05-01 Automatic channel scanning system

Country Status (1)

Country Link
JP (1) JPS60232715A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010088903A1 (en) * 2009-02-05 2010-08-12 Vkr Holding A/S A method of transmitting signals in a control system and a control system therefore

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010088903A1 (en) * 2009-02-05 2010-08-12 Vkr Holding A/S A method of transmitting signals in a control system and a control system therefore

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