JPH0358047U - - Google Patents
Info
- Publication number
- JPH0358047U JPH0358047U JP11958089U JP11958089U JPH0358047U JP H0358047 U JPH0358047 U JP H0358047U JP 11958089 U JP11958089 U JP 11958089U JP 11958089 U JP11958089 U JP 11958089U JP H0358047 U JPH0358047 U JP H0358047U
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- antenna
- switching
- variable
- antenna switching
- 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
- 238000001514 detection method Methods 0.000 claims description 6
- 230000003321 amplification Effects 0.000 claims 3
- 238000003199 nucleic acid amplification method Methods 0.000 claims 3
- 238000010586 diagram Methods 0.000 description 4
Description
第１図はこの考案の第１の実施例に係るＦＭダ
イバーシテイチユーナを示すブロツク図、第２図
はこの考案の第２の実施例に係るＦＭダイバーシ
テイチユーナを示すブロツク図、第３図は従来の
ＦＭダイバーシテイチユーナを示すブロツク図で
ある。
主な符号の説明、１０Ａ，１０Ｂ，１０Ｃ……
アンテナ、１２……アンテナ切換回路、１４……
フロントエンド、１６Ａ……中間周波増幅回路、
１８……ＦＭ検波器、２２……アンテナ切換制御
回路、３０……帯域幅可変ＩＦフイルタ回路、３
４……Ｓメータ回路、５０……ノイズレベル検出
回路、５２……比較回路、５４……ホールド回路
、６０，７２……帯域幅可変制御回路、７０……
切換頻度検出回路。
FIG. 1 is a block diagram showing an FM diversity tuner according to a first embodiment of this invention, FIG. 2 is a block diagram showing an FM diversity tuner according to a second embodiment of this invention, and FIG. 3 is a block diagram showing an FM diversity tuner according to a second embodiment of this invention. The figure is a block diagram showing a conventional FM diversity tuner. Explanation of main codes, 10A, 10B, 10C...
Antenna, 12... Antenna switching circuit, 14...
Front end, 16A...intermediate frequency amplifier circuit,
18...FM detector, 22...Antenna switching control circuit, 30...Bandwidth variable IF filter circuit, 3
4... S meter circuit, 50... Noise level detection circuit, 52... Comparison circuit, 54... Hold circuit, 60, 72... Bandwidth variable control circuit, 70...
Switching frequency detection circuit.
Claims (1)
を行うアンテナ切換回路と、アンテナ切換回路の
出力側に順に接続された各１つのフロントエンド
、中間周波増幅回路と、受信状態が悪化したとき
アンテナ切換回路を制御してアンテナの切り換え
を行わせるアンテナ切換制御回路と、を含むダイ
バーシテイチユーナにおいて、 中間周波増幅回路のＩＦフイルタ回路を、帯域
幅の可変な帯域幅可変ＩＦフイルタ回路とし、 受信信号中のノイズレベルを検出するノイズレ
ベル検出回路と、 ノイズレベル検出回路で検出されたノイズレベ
ルと所定の基準レベルを比較する比較回路と、 アンテナ別に比較回路の比較結果をホールドす
るホールド回路と、 ホールド回路でホールドされた情報に基づき、
帯域幅可変ＩＦフイルタ回路に対する帯域幅可変
制御を行う帯域幅可変制御回路と、 を備えたことを特徴とするダイバーシテイチユー
ナ。 (2) 複数のアンテナと、各アンテナの切り換え
を行うアンテナ切換回路と、アンテナ切換回路の
出力側に順に接続された各１つのフロントエンド
、中間周波増幅回路と、受信状態が悪化したとき
アンテナ切換回路を制御してアンテナの切り換え
を行わせるアンテナ切換制御回路と、を含むダイ
バーシテイチユーナにおいて、 中間周波増幅回路のＩＦフイルタ回路を、帯域
幅の可変な帯域幅可変ＩＦフイルタ回路とし、 アンテナ切換回路での切り換え頻度を検出する
切換頻度検出回路と、 切換頻度検出回路で検出された切り換え頻度に
基づき、帯域幅可変ＩＦフイルタ回路に対する帯
域幅可変制御を行う帯域幅可変制御回路と、 を装備したことを特徴とするダイバーシテイチユ
ーナ。[Claims for Utility Model Registration] (1) A plurality of antennas, an antenna switching circuit for switching each antenna, and one front end and intermediate frequency amplification circuit connected in sequence to the output side of the antenna switching circuit, An antenna switching control circuit that controls an antenna switching circuit to switch antennas when reception conditions deteriorate; A noise level detection circuit that uses a variable IF filter circuit to detect the noise level in the received signal, a comparison circuit that compares the noise level detected by the noise level detection circuit with a predetermined reference level, and a comparison result of the comparison circuit for each antenna. Based on the hold circuit that holds the information and the information held by the hold circuit,
A diversity tuner comprising: a variable bandwidth control circuit that performs variable bandwidth control on a variable bandwidth IF filter circuit. (2) A plurality of antennas, an antenna switching circuit that switches between each antenna, one front end each connected in sequence to the output side of the antenna switching circuit, an intermediate frequency amplification circuit, and an antenna switching circuit that switches the antenna when reception conditions deteriorate. In a diversity tuner including an antenna switching control circuit that controls the circuit and switches the antenna, the IF filter circuit of the intermediate frequency amplification circuit is made into a variable bandwidth IF filter circuit with a variable bandwidth, and the antenna switching Equipped with a switching frequency detection circuit that detects the switching frequency in the circuit, and a bandwidth variable control circuit that performs bandwidth variable control on the variable bandwidth IF filter circuit based on the switching frequency detected by the switching frequency detection circuit. Diversity Tachiyuna is characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11958089U JPH0358047U (en) | 1989-10-12 | 1989-10-12 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11958089U JPH0358047U (en) | 1989-10-12 | 1989-10-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0358047U true JPH0358047U (en) | 1991-06-05 |
Family
ID=31667696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11958089U Pending JPH0358047U (en) | 1989-10-12 | 1989-10-12 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0358047U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012175662A (en) * | 2011-02-24 | 2012-09-10 | Fujitsu Ltd | Radio device, communication control method, and radio communication system |
-
1989
- 1989-10-12 JP JP11958089U patent/JPH0358047U/ja active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012175662A (en) * | 2011-02-24 | 2012-09-10 | Fujitsu Ltd | Radio device, communication control method, and radio communication system |