JPH1031042A - Transmitting frequency measuring circuit - Google Patents
Transmitting frequency measuring circuitInfo
- Publication number
- JPH1031042A JPH1031042A JP8184649A JP18464996A JPH1031042A JP H1031042 A JPH1031042 A JP H1031042A JP 8184649 A JP8184649 A JP 8184649A JP 18464996 A JP18464996 A JP 18464996A JP H1031042 A JPH1031042 A JP H1031042A
- Authority
- JP
- Japan
- Prior art keywords
- frequency
- gate
- crystal oscillator
- pulse
- gps satellite
- 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.)
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Landscapes
- Measuring Frequencies, Analyzing Spectra (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、マイクロ波着陸シ
ステム地上局装置の送信周波数計測回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission frequency measuring circuit for a microwave landing system ground station apparatus.
【０００２】[0002]
【従来の技術】マイクロ波着陸システム（ＭＬＳ）地上
局装置における従来の送信周波数計測回路は、送信周波
数計測のためのゲート期間を生成するクロック信号とな
る水晶発振器の発振周波数によってゲート期間を設定し
て、該ゲート期間中に通過する送信源としての水晶発振
器の発振周波数に基づくパルスの数を計測している。2. Description of the Related Art A conventional transmission frequency measuring circuit in a microwave landing system (MLS) ground station device sets a gate period by an oscillation frequency of a crystal oscillator serving as a clock signal for generating a gate period for transmission frequency measurement. Thus, the number of pulses based on the oscillation frequency of the crystal oscillator as a transmission source that passes during the gate period is measured.
【０００３】具体的には、従来のＭＬＳ地上局装置の送
信周波数計測回路は図２に示すブロック図のように構成
されていた。More specifically, a transmission frequency measuring circuit of a conventional MLS ground station apparatus is configured as shown in a block diagram of FIG.
【０００４】すなわち、送信源となる水晶発振器１から
の発振出力は方向性結合器２を介して逓倍器３に供給し
て、逓倍のうえＭＬＳ地上局装置の送信信号として出力
している。方向性結合器２にて分岐された水晶発振器１
からの発振出力はプリスケーラ４に供給して計数可能な
周波数にまで分周し、プリスケーラ４において分周され
た信号は波形整形回路５に供給されて方形波パルスに波
形整形され、送信周波数カウンタ９に供給される。That is, an oscillation output from a crystal oscillator 1 serving as a transmission source is supplied to a multiplier 3 via a directional coupler 2, and is output as a transmission signal of the MLS ground station device after being multiplied. Crystal oscillator 1 branched by directional coupler 2
The oscillation output from the prescaler 4 is supplied to the prescaler 4 and frequency-divided to a frequency that can be counted. The signal divided by the prescaler 4 is supplied to the waveform shaping circuit 5 to be shaped into a square-wave pulse. Supplied to
【０００５】一方、送信周波数計測のためのゲート期間
を生成するクロック信号となる水晶発振器１６の発振出
力をカウンタ１７に供給して予め定めた所定期間、例え
ば１秒間、水晶発振器１６の発振周波数をカウンタ１７
において計数し、カウンタ１７における計数値に基づく
パルス幅のゲートパルスをゲート信号生成回路８にて生
成し、ゲート信号生成回路８において生成されたゲート
パルスのパルス幅（ゲート期間）の期間中、送信周波数
カウンタ９に供給された波形整形回路５からの出力方形
波パルスの数を送信周波数カウンタ９にて計数し、送信
周波数カウンタ９における計数値をレジスタ１０に一旦
記憶し、演算回路１１にて、レジスタ１０に一旦記憶し
た送信周波数計数値、プリスケーラ４の分周比および逓
倍器３の逓倍数に基づく値にしたがって送信周波数を求
めるように構成されている。On the other hand, the oscillation output of the crystal oscillator 16 serving as a clock signal for generating a gate period for measuring the transmission frequency is supplied to the counter 17 so that the oscillation frequency of the crystal oscillator 16 is set for a predetermined period, for example, one second. Counter 17
The gate signal generation circuit 8 generates a gate pulse having a pulse width based on the count value of the counter 17, and transmits the gate pulse during the pulse width (gate period) of the gate pulse generated in the gate signal generation circuit 8. The number of square wave pulses output from the waveform shaping circuit 5 supplied to the frequency counter 9 is counted by the transmission frequency counter 9, and the count value of the transmission frequency counter 9 is temporarily stored in the register 10. The transmission frequency is obtained in accordance with the transmission frequency count value once stored in the register 10, the division ratio of the prescaler 4, and the value based on the multiplication number of the multiplier 3.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、送信周
波数計測のためのゲート期間を生成するためのクロック
信号を発振する水晶発振器の発振周波数に偏差があると
該偏差に基づいてゲート期間が伸縮し、送信周波数を誤
計測するという問題点があった。However, if there is a deviation in the oscillation frequency of the crystal oscillator that oscillates the clock signal for generating the gate period for measuring the transmission frequency, the gate period expands and contracts based on the deviation, There is a problem that the transmission frequency is erroneously measured.
【０００７】ちなみに、ＭＬＳ地上局装置の送信周波数
の許容偏差は±１０ｋＨｚである。また、ＭＬＳ地上局
装置の送信周波数は５ＧＨｚ帯である。一例として、送
信源となる水晶発振器の発振周波数を１００ＭＨｚ、プ
リスケーラの分周比を４、逓倍器の逓倍数を５０とする
と、送信周波数カウンタで計測する周波数（パルス数）
の許容偏差は±５０Ｈｚ（計数値±５０）である。[0007] Incidentally, the allowable deviation of the transmission frequency of the MLS ground station apparatus is ± 10 kHz. The transmission frequency of the MLS ground station device is in a 5 GHz band. As an example, assuming that the oscillation frequency of a crystal oscillator serving as a transmission source is 100 MHz, the division ratio of the prescaler is 4, and the multiplication number of the multiplier is 50, the frequency (number of pulses) measured by the transmission frequency counter
Is ± 50 Hz (count value ± 50).
【０００８】この場合、送信源となる水晶発振器の発振
周波数の偏差が０でも、ゲート期間幅が１ｓｅｃ±２μ
ｓの範囲を外れると、許容周波数偏差を超える値を計測
することになる。In this case, even if the deviation of the oscillation frequency of the crystal oscillator as the transmission source is 0, the gate period width is 1 sec ± 2 μm.
If the value is out of the range of s, a value exceeding the allowable frequency deviation will be measured.
【０００９】本発明は、ゲート期間の伸縮による周波数
の誤計測を防止し、正確な計測が行える送信周波数計測
回路を提供することを目的とする。SUMMARY OF THE INVENTION It is an object of the present invention to provide a transmission frequency measurement circuit capable of preventing erroneous frequency measurement due to expansion and contraction of a gate period and performing accurate measurement.
【００１０】[0010]
【発明を解決するための手段】本発明にかかる送信周波
数計測回路は、送信源となる水晶発振器の発振周波数ま
たは前記水晶発振器の発振周波数に基づく周波数をゲー
ト期間計数して前記水晶発振器の発振周波数の計測を行
う、マイクロ波着陸システム地上局装置の送信周波数計
測回路において、ＧＰＳ衛星信号受信機によって受信し
たＧＰＳ衛星信号中の時刻情報に基づきゲート期間を生
成することを特徴とする。A transmission frequency measuring circuit according to the present invention counts a gate period of an oscillation frequency of a crystal oscillator serving as a transmission source or a frequency based on the oscillation frequency of the crystal oscillator to count the oscillation frequency of the crystal oscillator. In the transmission frequency measurement circuit of the microwave landing system ground station apparatus for performing the measurement, a gate period is generated based on time information in a GPS satellite signal received by a GPS satellite signal receiver.
【００１１】本発明にかかる送信周波数計測回路によれ
ば、ＧＰＳ衛星信号受信機によって受信したＧＰＳ衛星
信号中の時刻情報に基づきゲート期間が生成される。し
かるにＧＰＳ衛星信号中の時刻情報は正確、かつ安定し
ているために、マイクロ波着陸システム地上局装置の環
境条件の変化にも影響されず、常時正確な周波数計測が
行える。According to the transmission frequency measuring circuit of the present invention, a gate period is generated based on time information in a GPS satellite signal received by a GPS satellite signal receiver. However, the time information in the GPS satellite signal is accurate and stable, so that accurate frequency measurement can always be performed without being affected by changes in the environmental conditions of the microwave landing system ground station apparatus.
【００１２】本発明にかかる送信周波数計測回路は、送
信源となる水晶発振器の発振周波数または前記水晶発振
器の発振周波数に基づく周波数をゲート期間計数して前
記水晶発振器の発振周波数の計測を行う、マイクロ波着
陸システム地上局装置の送信周波数計測回路において、
ＧＰＳ衛星信号受信機と、ＧＰＳ衛星信号受信機によっ
て受信したＧＰＳ衛星信号中の時刻情報に基づく所定時
刻から所定期間経過した時刻の期間に至る周期をゲート
期間とするゲート期間生成手段とを備えたことを特徴と
する。A transmission frequency measuring circuit according to the present invention measures a oscillation frequency of the crystal oscillator by counting a gate period of an oscillation frequency of a crystal oscillator serving as a transmission source or a frequency based on the oscillation frequency of the crystal oscillator. In the transmission frequency measurement circuit of the wave landing system ground station equipment,
A GPS satellite signal receiver; and a gate period generation unit that sets a gate period to a period from a predetermined time based on time information in the GPS satellite signal received by the GPS satellite signal receiver to a period of time after a predetermined period has elapsed. It is characterized by the following.
【００１３】本発明にかかる送信周波数計測回路によれ
ば、ＧＰＳ衛星信号受信機によって受信したＧＰＳ衛星
信号中の時刻情報に基づく所定時刻から所定期間経過し
た時刻の期間に至るゲート期間がゲート期間生成手段に
よって生成される。しかるにＧＰＳ衛星信号中の時刻情
報は正確、かつ安定しているために、時刻情報に基づく
所定時刻から所定期間経過した時刻の期間に至るゲート
期間も正確であり、かつ安定しており、マイクロ波着陸
システム地上局装置の環境条件の変化にも影響されず、
常時正確な周波数計測が行える。According to the transmission frequency measuring circuit of the present invention, the gate period is generated from the predetermined time based on the time information in the GPS satellite signal received by the GPS satellite signal receiver to the period after the predetermined period has elapsed. Generated by the means. However, since the time information in the GPS satellite signal is accurate and stable, the gate period from a predetermined time based on the time information to a time after a predetermined period has elapsed is also accurate and stable. Not affected by changes in the environmental conditions of the landing system ground station equipment,
Accurate frequency measurement can always be performed.
【００１４】[0014]
【発明の実施の形態】以下、本発明にかかる送信周波数
計測回路を実施の一形態によって説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A transmission frequency measuring circuit according to the present invention will be described below with reference to an embodiment.
【００１５】図１は、本発明にかかる実施の一形態にか
かる送信周波数計測回路の構成を示すブロック図であ
る。FIG. 1 is a block diagram showing a configuration of a transmission frequency measuring circuit according to an embodiment of the present invention.
【００１６】送信源となる水晶発振器１からの発振出力
は方向性結合器２を介して逓倍器３に供給して、逓倍の
うえＭＬＳ地上局装置の送信信号として出力している。
方向性結合器２にて分岐された水晶発振器１からの発振
出力はプリスケーラ４に供給して計数可能な周波数にま
で分周し、プリスケーラ４において分周された信号は波
形整形回路５に供給されて方形波パルスに波形整形さ
れ、送信周波数カウンタ９に供給される。The oscillation output from the crystal oscillator 1 serving as a transmission source is supplied to a multiplier 3 via a directional coupler 2, and is output as a transmission signal of the MLS ground station device after being multiplied.
The oscillation output from the crystal oscillator 1 branched by the directional coupler 2 is supplied to the prescaler 4 to divide the frequency into a countable frequency, and the signal divided by the prescaler 4 is supplied to the waveform shaping circuit 5. The pulse is shaped into a square wave pulse and supplied to the transmission frequency counter 9.
【００１７】一方、水晶発振器１６とカウンタ１７に代
わって、ＧＰＳ衛星信号受信機６とＧＰＳ衛星信号受信
機６にて受信したＧＰＳ衛星信号中からＧＰＳ時刻情報
をデコードするデコーダ７とを設け、ＧＰＳ衛星信号受
信機６にて受信したＧＰＳ衛星信号中からＧＰＳ時刻情
報を求め、求めた時刻情報をデコーダ７によってデコー
ドしてゲート信号生成回路８に送出し、ゲート信号生成
回路８にて送信周波数計測のためのゲート期間を形成す
るためのゲートパルスを生成し、生成されたゲートパル
スのパルス幅の期間中、送信周波数カウンタ９に供給さ
れた波形整形回路５からの出力方形波パルスの数を送信
周波数カウンタ９にて計数し、送信周波数カウンタ９に
おける計数値をレジスタ１０に一旦記憶して、演算回路
１１にて、レジスタ１０に一旦記憶した送信周波数計数
値、プリスケーラ４の分周比、逓倍器３の逓倍数に基づ
く値にしたがって送信周波数を求めるように構成されて
いる。On the other hand, in place of the crystal oscillator 16 and the counter 17, a GPS satellite signal receiver 6 and a decoder 7 for decoding GPS time information from GPS satellite signals received by the GPS satellite signal receiver 6 are provided. The GPS time information is obtained from the GPS satellite signal received by the satellite signal receiver 6, the obtained time information is decoded by the decoder 7 and transmitted to the gate signal generation circuit 8, and the transmission frequency is measured by the gate signal generation circuit 8. A gate pulse for forming a gate period is generated, and during the period of the pulse width of the generated gate pulse, the number of square wave pulses output from the waveform shaping circuit 5 supplied to the transmission frequency counter 9 is transmitted. Counting is performed by the frequency counter 9, the count value of the transmission frequency counter 9 is temporarily stored in the register 10, Once the stored transmission frequency count 10, the prescaler 4, is configured to determine the transmission frequency according to the value based on the multiplication number of the multiplier 3.
【００１８】上記のように構成される本発明の実施の一
形態にかかる送信周波数計測回路において、ＧＰＳ衛星
信号受信機６によりＧＰＳ衛星信号が受信され、ＧＰＳ
衛星信号中からＧＰＳ時刻情報が取り出される。ＧＰＳ
衛星にはルビジウム（Ｒｂ）時計を搭載しており、ＧＰ
Ｓ衛星信号中にはルビジウム時計によるＧＰＳ時刻情報
が含まれており、ＧＰＳ時刻情報がＧＰＳ衛星信号受信
機６から取り出される。In the transmission frequency measuring circuit according to one embodiment of the present invention configured as described above, a GPS satellite signal is received by the GPS satellite signal
GPS time information is extracted from the satellite signal. GPS
The satellite is equipped with a rubidium (Rb) clock.
The S satellite signal contains GPS time information based on a rubidium clock, and the GPS time information is extracted from the GPS satellite signal receiver 6.
【００１９】この時刻情報はデコーダ７に送出される。
時刻情報を受けたデコーダ７からは、ある時刻でゲート
信号生成回路８にカウント開始パルスが送出される。こ
のカウント開始パルスを受けてゲート信号生成回路８は
ゲートパルスを発生し、ゲートパルスを受けて送信周波
数カウンタ９にて送信周波数パルスの計数が開始され
る。This time information is sent to the decoder 7.
The decoder 7 that has received the time information sends a count start pulse to the gate signal generation circuit 8 at a certain time. The gate signal generation circuit 8 generates a gate pulse in response to the count start pulse, and the transmission frequency counter 9 starts counting transmission frequency pulses in response to the gate pulse.
【００２０】その１秒後の時刻情報を取得したら、デコ
ーダ７はカウント終了パルスがゲート信号生成回路８に
送出される。このカウント終了パルスを受けてゲート信
号生成回路８はゲートパルスを消滅させる。ゲートパル
スの消滅を受けて送信周波数カウンタ９にて送信周波数
パルスの計数が終了される。After obtaining the time information one second after that, the decoder 7 sends a count end pulse to the gate signal generation circuit 8. Upon receiving the count end pulse, the gate signal generation circuit 8 extinguishes the gate pulse. In response to the disappearance of the gate pulse, the transmission frequency counter 9 stops counting transmission frequency pulses.
【００２１】したがって、ゲートパルス幅は１秒に制御
され、送信周波数カウンタ９は波形整形回路５から出力
される方形パルスを１秒間計数を行う。送信周波数カウ
ンタ９において計数された値は、従来と同じように演算
回路１１により送信周波数に換算される。Therefore, the gate pulse width is controlled to one second, and the transmission frequency counter 9 counts the square pulses output from the waveform shaping circuit 5 for one second. The value counted by the transmission frequency counter 9 is converted into a transmission frequency by the arithmetic circuit 11 as in the conventional case.
【００２２】しかるに、ＧＰＳ時刻情報は正確であるた
め、ゲート時間が一定となるため、正確に送信周波数の
計測ができる。However, since the GPS time information is accurate and the gate time is constant, the transmission frequency can be accurately measured.
【００２３】[0023]
【発明の効果】以上説明したように本発明にかかる送信
周波数計測回路によれば、ＧＰＳ衛星信号受信機によっ
て受信したＧＰＳ衛星信号中の時刻情報に基づきゲート
期間を生成するため、マイクロ波着陸システム地上局装
置の内部に送信周波数計測のためのゲート期間を生成す
るためのクロック信号を発振する水晶発振器として高精
度かつ高安定度の水晶発振器をもつ必要はなく、常に一
定なゲート期間を生成できて、送信源となる水晶発振器
による送信周波数の正確な計測が可能になるという効果
が得られる。As described above, according to the transmission frequency measuring circuit of the present invention, the microwave landing system is used to generate the gate period based on the time information in the GPS satellite signal received by the GPS satellite signal receiver. It is not necessary to have a high-precision and high-stability crystal oscillator as a crystal oscillator that oscillates a clock signal to generate a gate period for transmission frequency measurement inside the ground station equipment, and it can always generate a constant gate period As a result, it is possible to obtain an effect that the transmission frequency can be accurately measured by the crystal oscillator serving as the transmission source.
【００２４】また、本発明にかかる送信周波数計測回路
によれば、ＧＰＳ衛星信号中の時刻情報はマイクロ波着
陸システム地上局装置の環境条件に影響されることはな
く、常時正確な周波数計測が行えるという効果が得られ
る。Further, according to the transmission frequency measuring circuit of the present invention, the time information in the GPS satellite signal is not affected by the environmental conditions of the ground station apparatus of the microwave landing system, and the frequency can always be accurately measured. The effect is obtained.
【図１】本発明の実施の一形態にかかる送信周波数計測
回路の構成を示すブロック図である。FIG. 1 is a block diagram illustrating a configuration of a transmission frequency measurement circuit according to an embodiment of the present invention.
【図２】従来の送信周波数計測回路の構成を示すブロッ
ク図である。FIG. 2 is a block diagram illustrating a configuration of a conventional transmission frequency measurement circuit.
１ 送信源となる水晶発振器 ２ 方向性結合
器 ３ 逓倍器 ４ プリスケー
ラ ５ 波形整形回路 ６ ＧＰＳ衛星
信号受信機 ７ デコーダ ８ ゲート信号
生成回路REFERENCE SIGNS LIST 1 crystal oscillator serving as transmission source 2 directional coupler 3 multiplier 4 prescaler 5 waveform shaping circuit 6 GPS satellite signal receiver 7 decoder 8 gate signal generation circuit
Claims (2)
は前記水晶発振器の発振周波数に基づく周波数をゲート
期間計数して前記水晶発振器の発振周波数の計測を行
う、マイクロ波着陸システム地上局装置の送信周波数計
測回路において、ＧＰＳ衛星信号受信機によって受信し
たＧＰＳ衛星信号中の時刻情報に基づきゲート期間を生
成することを特徴とする送信周波数計測回路。1. A transmission of a ground station system for a microwave landing system, wherein the oscillation frequency of a crystal oscillator serving as a transmission source or a frequency based on the oscillation frequency of the crystal oscillator is counted for a gate period to measure the oscillation frequency of the crystal oscillator. A transmission frequency measurement circuit for generating a gate period based on time information in a GPS satellite signal received by a GPS satellite signal receiver.
は前記水晶発振器の発振周波数に基づく周波数をゲート
期間計数して前記水晶発振器の発振周波数の計測を行
う、マイクロ波着陸システム地上局装置の送信周波数計
測回路において、ＧＰＳ衛星信号受信機と、ＧＰＳ衛星
信号受信機によって受信したＧＰＳ衛星信号中の時刻情
報に基づく所定時刻から所定期間経過した時刻の期間に
至る周期をゲート期間とするゲート期間生成手段とを備
えたことを特徴とする送信周波数計測回路。2. A microwave landing system ground station apparatus for measuring the oscillation frequency of a crystal oscillator by counting a gate period of an oscillation frequency of a crystal oscillator serving as a transmission source or a frequency based on the oscillation frequency of the crystal oscillator. In the frequency measurement circuit, a GPS satellite signal receiver, and a gate period generation having a period from a predetermined time based on time information in the GPS satellite signal received by the GPS satellite signal receiver to a period from a predetermined time period to a time period as a gate period And a transmission frequency measurement circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8184649A JPH1031042A (en) | 1996-07-15 | 1996-07-15 | Transmitting frequency measuring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8184649A JPH1031042A (en) | 1996-07-15 | 1996-07-15 | Transmitting frequency measuring circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH1031042A true JPH1031042A (en) | 1998-02-03 |
Family
ID=16156936
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8184649A Pending JPH1031042A (en) | 1996-07-15 | 1996-07-15 | Transmitting frequency measuring circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH1031042A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006300753A (en) * | 2005-04-21 | 2006-11-02 | National Institute Of Advanced Industrial & Technology | Distance measuring equipment |
| JP2016213712A (en) * | 2015-05-11 | 2016-12-15 | 富士通株式会社 | Radio communication device and frequency error measurement method |
-
1996
- 1996-07-15 JP JP8184649A patent/JPH1031042A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006300753A (en) * | 2005-04-21 | 2006-11-02 | National Institute Of Advanced Industrial & Technology | Distance measuring equipment |
| JP2016213712A (en) * | 2015-05-11 | 2016-12-15 | 富士通株式会社 | Radio communication device and frequency error measurement method |
| US9621338B2 (en) | 2015-05-11 | 2017-04-11 | Fujitsu Limited | Radio communication device and frequency error measurement method |
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