JP3088105B2 - Temperature characteristic compensation method for SAW filter - Google Patents
Temperature characteristic compensation method for SAW filterInfo
- Publication number
- JP3088105B2 JP3088105B2 JP01193746A JP19374689A JP3088105B2 JP 3088105 B2 JP3088105 B2 JP 3088105B2 JP 01193746 A JP01193746 A JP 01193746A JP 19374689 A JP19374689 A JP 19374689A JP 3088105 B2 JP3088105 B2 JP 3088105B2
- Authority
- JP
- Japan
- Prior art keywords
- saw filter
- frequency
- intermediate frequency
- temperature
- temperature characteristic
- 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
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は第１中間周波フィルタとしてSAWフィルタを
用いたダブルスーパーヘテロダイン受信機に関する。Description: TECHNICAL FIELD The present invention relates to a double superheterodyne receiver using a SAW filter as a first intermediate frequency filter.
自動車電話等のダブルスーパーヘテロダイン受信機に
おいては、数＋MHzの第１中間周波数を使用しており、
この周波数帯に適応するSAW（バンド・パス）フィルタ
としては、従来ST−カット水晶上に形成されたものを使
用している。In a double superheterodyne receiver such as a car telephone, a first intermediate frequency of several + MHz is used,
As a SAW (band pass) filter adapted to this frequency band, a filter formed on an ST-cut quartz crystal is conventionally used.
上述した従来のSAWフィルタは、その中心周波数の温
度変動が−30℃〜＋65℃の範囲で約100ppmと大きく、こ
のように広い温度範囲でバンド・パス・フィルタとして
用いるためには、温度変動を見込んで所要通過帯域幅と
比べて必要以上に広帯域のフィルタを用いる必要があっ
た。そして、このSAWフィルタが広帯域であるために、
隣接チャンネル波からの妨害を受け易いという欠点があ
った（第３図）。The above-described conventional SAW filter has a large temperature variation of the center frequency of about 100 ppm in a range of -30 ° C to + 65 ° C. In anticipation, it was necessary to use a filter having a wider bandwidth than necessary compared to the required pass bandwidth. And because this SAW filter has a wide band,
There is a drawback that it is susceptible to interference from adjacent channel waves (FIG. 3).
前記目的を達成するため、本発明に係るSAWフィルタ
の温度特性補償方式は、第１中間周波フィルタとしてSA
Wフィルタを用いたダブルスーパーヘテロダイン受信機
において、周囲の温度を検出する温度検出部と、第１及
び第２局発部と、該温度検出部からの情報に基いて該第
１及び第２局発部の発振周波数を制御し、第２中間周波
数を一定に保ちつつ第１中間周波数がSAWフィルタの中
心周波数と同様の温度特性を持つように制御する制御部
とを有するものである。In order to achieve the above object, a temperature characteristic compensation method for a SAW filter according to the present invention includes a SA
In a double superheterodyne receiver using a W filter, a temperature detector for detecting an ambient temperature, first and second local oscillators, and first and second stations based on information from the temperature detector. A control unit that controls the oscillation frequency of the emission unit and controls the first intermediate frequency to have the same temperature characteristics as the center frequency of the SAW filter while keeping the second intermediate frequency constant.
以下、本発明の一実施例を図により説明する。 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例を示すブロック図である。 FIG. 1 is a block diagram showing one embodiment of the present invention.
図において、１は第１の混合器、２はSAWフィルタ、
３は第２の混合器、４は第１局発部、５は第２局発部、
６は制御部、７は温度検出部である。In the figure, 1 is a first mixer, 2 is a SAW filter,
3 is the second mixer, 4 is the first localizer, 5 is the second localizer,
Reference numeral 6 denotes a control unit, and 7 denotes a temperature detection unit.
温度検出部７から出力される温度情報は制御部６へ渡
され、制御部６はその情報を基に第１局発部４及び第２
局発部５の発振周波数を、第１中間周波b,b′の周波数
がSAWフィルタ２の中心周波数と同様の温度変動をし、
かつ、第２中間周波ｃの周波数が一定になるように制御
する。The temperature information output from the temperature detecting unit 7 is passed to the control unit 6, and the control unit 6 performs the first local oscillation unit 4 and the second
The oscillation frequency of the local oscillator 5 is changed so that the frequency of the first intermediate frequency b, b 'fluctuates in the same manner as the center frequency of the SAW filter 2,
In addition, control is performed so that the frequency of the second intermediate frequency c is constant.
すなわち、制御部６は、高周波ａの周波数をfR、第１
中間周波数をIF1、第２中間周波数をIF2、第１局発周波
数をfL1、第２局発周波数をfL2とすると、fR−fL1（ま
たはfR＋fL1）＝IF1がSAWフィルタ２の中心周波数温度
変動に追従するようにfL1を制御し、IF1−fL2（またはI
F1＋fL2）＝IF2が一定に保たれるようにfL2を制御す
る。したがって、本発明によれば、第２図に示すように
SAWフィルタ２の帯域を所要通過帯域幅まで狭めること
が可能となり、隣接チャンネル波からの妨害に対し強く
することが可能となる。第２図において、fDは第１中間
周波中心周波数、fAは隣接チャンネル波中心周波数をそ
れぞれ示す。That is, the control unit 6 sets the frequency of the high frequency a to fR,
If the intermediate frequency is IF1, the second intermediate frequency is IF2, the first local oscillation frequency is fL1, and the second local oscillation frequency is fL2, fR−fL1 (or fR + fL1) = IF1 follows the center frequency temperature fluctuation of the SAW filter 2. FL1 so that IF1-fL2 (or I
F1 + fL2) = fL2 is controlled so that IF2 is kept constant. Therefore, according to the present invention, as shown in FIG.
It is possible to narrow the band of the SAW filter 2 to the required pass band width, and it is possible to increase the resistance to interference from adjacent channel waves. In FIG. 2, fD indicates the first intermediate frequency center frequency, and fA indicates the adjacent channel wave center frequency.
以上説明したように本発明は、温度変動に対して第１
中間周波数を常にSAWフィルタ中心周波数に追従させる
ことにより、SAWフィルタの帯域を所要通過帯域幅まで
狭めることができ、このため隣接チャンネル波からの妨
害に対して強くなるという効果がある。As described above, the present invention provides the first method against temperature fluctuation.
By making the intermediate frequency always follow the center frequency of the SAW filter, the band of the SAW filter can be narrowed down to a required pass bandwidth, and therefore, there is an effect that the SAW filter is more resistant to interference from adjacent channel waves.
第１図は本発明の一実施例を示すブロック図、第２図は
本発明のSAWフィルタ減衰特性を示す図、第３図は従来
のSAWフィルタ減衰特性を示す図である。 １……第１の混合器、２……SAWフィルタ ３……第２の混合器、４……第１局発部 ５……第２の局発部、６……制御部 ７……温度検出部、ａ……高周波 b,b′……第１中間周波 ｃ……第２中間周波FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing a SAW filter attenuation characteristic of the present invention, and FIG. 3 is a diagram showing a conventional SAW filter attenuation characteristic. 1 1st mixer, 2 SAW filter 3 2nd mixer 4 1st local oscillator 5 2nd local oscillator 6, control unit 7 temperature Detector, a: High frequency b, b ': First intermediate frequency c: Second intermediate frequency
Claims (1)
を用いたダブルスーパーヘテロダイン受信機において、
周囲の温度を検出する温度検出部と、第１及び第２局発
部と、該温度検出部からの情報に基いて該第１及び第２
局発部の発振周波数を制御し、第２中間周波数を一定に
保ちつつ第１中間周波数がSAWフィルタの中心周波数と
同様の温度特性を持つように制御する制御部とを有する
ことを特徴とするSAWフィルタの温度特性補償方式。In a double superheterodyne receiver using a SAW filter as a first intermediate frequency filter,
A temperature detection unit for detecting an ambient temperature, first and second localization units, and the first and second localization units based on information from the temperature detection unit.
A control unit that controls the oscillation frequency of the local oscillation unit and controls the first intermediate frequency to have a temperature characteristic similar to the center frequency of the SAW filter while keeping the second intermediate frequency constant. SAW filter temperature characteristic compensation method.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01193746A JP3088105B2 (en) | 1989-07-26 | 1989-07-26 | Temperature characteristic compensation method for SAW filter |
| GB9015768A GB2234127B (en) | 1989-07-18 | 1990-07-18 | Double superheterodyne receiver with arrangement for compensating for temperature-dependent performance characteristics of a surface acoustic wave filter |
| US07/895,141 US5204972A (en) | 1989-07-18 | 1992-06-05 | Arrangement for compensating for temperature dependent performance characteristics of surface acoustic wave filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01193746A JP3088105B2 (en) | 1989-07-26 | 1989-07-26 | Temperature characteristic compensation method for SAW filter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0358522A JPH0358522A (en) | 1991-03-13 |
| JP3088105B2 true JP3088105B2 (en) | 2000-09-18 |
Family
ID=16313123
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01193746A Expired - Fee Related JP3088105B2 (en) | 1989-07-18 | 1989-07-26 | Temperature characteristic compensation method for SAW filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3088105B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3185418A1 (en) * | 2015-12-21 | 2017-06-28 | Tesat Spacecom GmbH & Co. KG | Method for operating a selection switching device for signals |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH057166A (en) * | 1991-06-26 | 1993-01-14 | Nec Corp | Heterodyne system receiver |
| FR2905537B1 (en) * | 2006-08-30 | 2012-11-16 | Thales Sa | METHOD AND DEVICE FOR COMPENSATING THE DERIVATIVE DUE TO THE VARIATION OF A PARAMETER IN A FILTER |
-
1989
- 1989-07-26 JP JP01193746A patent/JP3088105B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3185418A1 (en) * | 2015-12-21 | 2017-06-28 | Tesat Spacecom GmbH & Co. KG | Method for operating a selection switching device for signals |
| US10128811B2 (en) | 2015-12-21 | 2018-11-13 | Tesat-Spacecom Gmbh & Co Kg | Method for operating a selective switching device for signals |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0358522A (en) | 1991-03-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2104215A1 (en) | Radio receiver for forming a baseband signal of time-varying frequencies | |
| NO840920L (en) | PROCEDURE FOR VOTING THE CIRCUIT CIRCUITS IN AN INFORMATION RECEIVER | |
| JPH05327378A (en) | Automatic gain control circuit for radio communication equipment | |
| US5410742A (en) | SAW electric part and frequency conversion circuit | |
| JP3088105B2 (en) | Temperature characteristic compensation method for SAW filter | |
| JPH0710051B2 (en) | Wireless receiver | |
| JPH07221663A (en) | Super heterodyne reception system | |
| US6026114A (en) | Transmitting and receiving apparatus of time division full-duplex spread spectrum communication system | |
| JP2705794B2 (en) | Receiving machine | |
| JP2822461B2 (en) | Temperature characteristic compensation method for SAW intermediate frequency filter | |
| KR0178107B1 (en) | Wideband frequency moudlating circuit using crystal | |
| JPS6346829A (en) | Clock generating circuit for control circuit of multi-channel receiver | |
| JP2506027B2 (en) | AFC circuit | |
| JPH01320827A (en) | Control system for notch frequency | |
| JPS5844368A (en) | Compressing device for pulse of radar | |
| DK162000C (en) | NOISE REDUCTION SYSTEM, FOR FM RADIO RECEIVERS, AT LOW SIGNAL LEVELS. | |
| JP2526057B2 (en) | Mobile radio with frequency stabilization function | |
| JPS6340500B2 (en) | ||
| JP3298237B2 (en) | High frequency local oscillator circuit | |
| US3739286A (en) | Crystal filter with temperature compensation | |
| JP2002335178A (en) | Frequency scanning receiver | |
| JPS56114453A (en) | Fm feedback type demodulating circuit | |
| JPH0548451A (en) | Frequency synthesizer | |
| JPH0456552A (en) | Fsk signal receiver | |
| JPH0548569A (en) | Spread spectrum communicatoin equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |