JP2652950B2 - Pulse compression radar device - Google Patents
Pulse compression radar deviceInfo
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- JP2652950B2 JP2652950B2 JP63040428A JP4042888A JP2652950B2 JP 2652950 B2 JP2652950 B2 JP 2652950B2 JP 63040428 A JP63040428 A JP 63040428A JP 4042888 A JP4042888 A JP 4042888A JP 2652950 B2 JP2652950 B2 JP 2652950B2
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- pulse
- signal
- short
- transmission
- long
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明はパルス圧縮レーダ装置に係り、特に周波数変
調の施された長パルス幅の送信信号を用いるパルス圧縮
レーダ装置に関する。Description: BACKGROUND OF THE INVENTION The present invention relates to a pulse compression radar device, and more particularly to a pulse compression radar device using a frequency-modulated long pulse width transmission signal.
（従来の技術） 一般に、レーダ装置においては、送信電力の受信機へ
の漏れのため、その時間は信号を受信できない状態とな
る。特にパルス圧縮レーダ装置においては、送信信号パ
ルスのパルス幅が比較的長いため、受信できない時間が
長くなり、近距離の目標が見えないという不都合を生ず
る。そこで、従来のパルス圧縮レーダ装置にあっては、
長／短パルス複合方式によって問題解決を図っている。(Prior Art) Generally, in a radar apparatus, a signal cannot be received during that time due to leakage of transmission power to a receiver. In particular, in the pulse compression radar device, since the pulse width of the transmission signal pulse is relatively long, the time during which the signal cannot be received becomes long, which causes a disadvantage that a target at a short distance cannot be seen. Therefore, in the conventional pulse compression radar device,
The problem is solved by a combined long / short pulse system.
即ち、送信時点から送信信号のパルス幅の時間内にお
いては圧縮パルス幅に相当する短パルスで送受信を行
い、その後は本来の送信信号（長パルス）を用い、短パ
ルスについての受信信号と長パルスについてパルス圧縮
受信した信号とを合成する方式である。That is, transmission and reception are performed with a short pulse corresponding to the compressed pulse width within the time of the pulse width of the transmission signal from the transmission time, and thereafter, the original transmission signal (long pulse) is used, and the reception signal and the long pulse for the short pulse are used. Is a method of synthesizing a signal received with pulse compression.
第３図は長／短パルス複合方式を採用するパルス圧縮
レーダ装置の構成例を示す。第３図において、１はアン
テナ、２はサーキュレータ、５は信号選択器、６は受信
信号の出力端子、７はパルス圧縮受信機、８は長パルス
送信機、９は受信用長／短パルス切替器、10は短パルス
受信機、11は遅延線路、12は送信用長／短パルス切替
器、13は短パルス送信機、14は長／短パルス切替信号の
入力端子である。FIG. 3 shows an example of the configuration of a pulse compression radar device employing a combined long / short pulse system. In FIG. 3, 1 is an antenna, 2 is a circulator, 5 is a signal selector, 6 is an output terminal of a received signal, 7 is a pulse compression receiver, 8 is a long pulse transmitter, and 9 is long / short pulse switching for reception. , 10 is a short pulse receiver, 11 is a delay line, 12 is a transmission long / short pulse switch, 13 is a short pulse transmitter, and 14 is a long / short pulse switching signal input terminal.
次に、第４図を参照して動作を説明する。 Next, the operation will be described with reference to FIG.
第４図（１）に示すように、入力端子14に印加される
長／短パルス切替信号は１送信周期Ｔの開始時点からの
一定期間TSを短パルス送受信の期間として、以後を長パ
ルス送受信の期間とするもので、この信号に基づき送信
用および受信用の切替器12および同９は所要の切替動作
を行う。As shown in FIG. 4 (1), the long / short pulse switching signal applied to the input terminal 14 has a fixed period T S from the start of one transmission cycle T as a short pulse transmission / reception period, and thereafter a long pulse. The transmission and reception switches 12 and 9 perform required switching operations based on this signal.
まず、入力端子14に短パルス送受信を指示する長／短
パルス切替信号が入力すると、短パルス送信機13が出力
する圧縮パルス幅に相当する短パルスからなる送信信号
は、送信用長／短パルス切替器12を通り、サーキュレー
タ２を介してアンテナ１から空気に放射される（第４図
（２））。First, when a long / short pulse switching signal for instructing short pulse transmission / reception is input to the input terminal 14, the transmission signal composed of short pulses corresponding to the compressed pulse width output from the short pulse transmitter 13 is transmitted as long / short pulses for transmission. The light passes through the switch 12 and is radiated from the antenna 1 to the air via the circulator 2 (FIG. 4 (2)).
目標から反射して来た信号は再びアンテナ１で受信さ
れたサーキュレータ２、受信用長／短パルス切替器９を
通って短パルス受信機10に入力され（第４図（３））、
そこで信号処理された後、遅延線路11を経て、後述する
長パルス受信信号と重畳すべく時間的整合をとるための
時間Tdだけ遅延して（第４図（４））信号選択器５に入
力される。The signal reflected from the target is again input to the short pulse receiver 10 through the circulator 2 and the long / short pulse switching device 9 received by the antenna 1 (FIG. 4 (3)).
Then, after signal processing, the signal is delayed by a time Td for time matching for superimposition with a long pulse reception signal described later (FIG. 4 (4)) via a delay line 11 (FIG. 4 (4)). Is entered.
このようにして、送信周期Ｔのうち長パルス送受信に
先立って割り当てる短パルス送受信周期としての一定期
間TS内での短パルス受信信号は信号選択器５に入力され
る。そして、一定期間TSを経過すると、入力端子14に長
パルス送受信を指示する長／短パルス切替信号が入力
し、パルス圧縮用長パルス送信機８が出力するパルス幅
TL（TL≦TS）の送信信号が送信用長／短パルス切替器1
2、サーキューレータ２を介したアンテナ１から放射さ
れ（第４図（５））、目標で反射されて受信される。受
信された信号はパルス圧縮受信機７に入力され、通常周
波数対遅延特性が送信信号とは逆特性のフィルタに通し
て尖鋭な圧縮パルスとするパルス圧縮処理を施す信号処
理された後（第４図（６））、信号選択器５に入力され
る。In this way, the short pulse reception signal within the fixed period T S as the short pulse transmission / reception cycle allocated prior to the long pulse transmission / reception in the transmission cycle T is input to the signal selector 5. After a lapse of a predetermined period T S , a long / short pulse switching signal for instructing long pulse transmission / reception is input to the input terminal 14, and the pulse width output from the long pulse transmitter 8 for pulse compression is output.
The transmission signal of T L (T L ≤T S ) is a long / short pulse switch 1 for transmission.
2. The light is radiated from the antenna 1 via the circulator 2 (FIG. 4 (5)), reflected by the target, and received. The received signal is input to the pulse compression receiver 7, and is subjected to a signal processing in which a pulse compression process is performed through a filter having a frequency-delay characteristic opposite to that of the transmission signal to generate a sharp compressed pulse (fourth signal). (FIG. 6), the signal is input to the signal selector 5.
信号選択器５では、一定期間TSの期間では遅延線路11
の出力を選択し、その後の期間ではパルス圧縮受信機７
の出力を選択する。その結果、信号選択器５は、第４図
（７）に示すように、短パルス受信信号（ａ）と長パル
ス受信信号（ｂ）を時間合成して出力することになる。
なお、第４図で示す信号波形は包絡線のみを示してあ
る。In the signal selector 5, the delay line 11 during a certain period T S
Of the pulse compression receiver 7 during the subsequent period.
Select the output of As a result, as shown in FIG. 4 (7), the signal selector 5 time-synthesizes the short pulse reception signal (a) and the long pulse reception signal (b) and outputs the result.
The signal waveform shown in FIG. 4 shows only the envelope.
（発明が解決しようとする課題） しかし、前述した長／短パルス複合方式を採用する従
来のパルス圧縮レーダ装置にあっては、次のような種々
の問題点がある。(Problems to be Solved by the Invention) However, the conventional pulse compression radar apparatus employing the above-described combined long / short pulse method has the following various problems.
まず、短パルス送受信期間（TS）以降に受信される短
パルスはすべて、長パルス用のパルス圧縮受信機７に入
力され擬像となる。また、短パルスを送受信するだけの
時間を余計に必要とする。First, all short pulses received after the short pulse transmission / reception period (T S ) are input to the long-pulse pulse compression receiver 7 and become pseudo images. In addition, extra time is required for transmitting and receiving short pulses.
さらに、装置構成上の問題として、短パルス送信機1
3、送信用長／短パルス切替器12等を必要とし、装置構
成が複雑化し装置規模の縮小化を図るのが困難である。Furthermore, as a problem in the device configuration, the short pulse transmitter 1
3. Since the transmission long / short pulse switch 12 and the like are required, the device configuration is complicated, and it is difficult to reduce the device scale.
本発明は、このような従来の問題点に鑑みなされたも
ので、その目的は、構成の簡素化が図れるとともに、短
パルス送受信を行うことなく近距離にある目標の検出を
可能とするパルス圧縮レーダ装置を提供することにあ
る。SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional problem, and has as its object to simplify the configuration and achieve pulse compression that enables detection of a target at a short distance without performing short pulse transmission / reception. An object of the present invention is to provide a radar device.
（課題を解決するための手段） 前記目的を達成するために、本発明に係るパルス圧縮
レーダ装置は次の如き構成を有する。(Means for Solving the Problems) In order to achieve the above object, a pulse compression radar device according to the present invention has the following configuration.
即ち、本発明のパルス圧縮レーダ装置は、周波数変調
の施された長パルス幅の送信信号を用いるパルス圧縮レ
ーダ装置において；受信信号を２方向へ分配する信号分
配器と；前記信号分配器の一方の出力を受けて前記送信
信号送出時から所定時間経過後の目標検出が不可能な近
距離目標受信領域に連続的に入力する前記送信信号によ
る受信信号の後縁部分の周波数成分を抽出し前記後縁部
分の時間幅に対応する狭パルスとして出力する狭帯域フ
ィルタを有する狭帯域受信機と；前記信号分配器の他方
の出力を受けてパルス圧縮処理を施すパルス圧縮受信機
と；送信信号の長パルス幅に基づいて前記近距離目標受
信領域に対応した所定時間経過時までの近距離目標受信
時には前記狭帯域受信機の出力する狭パルスを選択し所
定時間経過以後は前記パルス圧縮受信機の出力を選択し
それらを時間軸上で合成して出力する信号選択器と；を
備えることを特徴とするものである。That is, a pulse compression radar apparatus according to the present invention is a pulse compression radar apparatus using a frequency-modulated long pulse width transmission signal; a signal distributor for distributing a received signal in two directions; and one of the signal distributors Receiving the output of the transmission signal and extracting the frequency component of the trailing edge of the reception signal by the transmission signal continuously input to the short-distance target reception area where the target cannot be detected after the elapse of a predetermined time from the transmission signal transmission. A narrow-band receiver having a narrow-band filter that outputs a narrow pulse corresponding to a time width of a trailing edge portion; a pulse-compression receiver that receives the other output of the signal distributor and performs a pulse compression process; At the time of short-distance target reception until the predetermined time corresponding to the short-distance target reception area based on the long pulse width, a narrow pulse output from the narrow-band receiver is selected, and after the predetermined time elapses, the narrow pulse is selected. It is characterized in further comprising a; selects the output of the pulse compression receiver and signal selector to output the synthesized them in time.
（作 用） 次に、前記の如く構成される本発明のパルス圧縮レー
ダ装置の作用を説明する。(Operation) Next, the operation of the pulse compression radar apparatus of the present invention configured as described above will be described.
周波数変調の施された長パルス幅の送信信号について
の受信信号は、信号分配器を介して狭帯域受信機とパル
ス圧縮受信機とにそれぞれ入力する。A received signal of a frequency-modulated long pulse width transmission signal is input to a narrowband receiver and a pulse compression receiver via a signal distributor.
そして、狭帯域受信機では受信信号の後縁部分の周波
数成分を抽出し、それを信号選択器に出力する。また、
パルス圧縮受信機では受信信号にパルス圧縮処理を施
し、それを信号選択器に出力する。周知のように、パル
ス圧縮受信機では送信信号送出期間、即ち送信パルス幅
内では目標検出ができない。そこで、信号選択器では、
送信信号送信時から所定時間経過時までの近距離目標受
信時には前記狭帯域受信機の出力を選択し所定時間経過
以後は前記パルス圧縮受信機の出力を選択しそれらを時
間合成して出力するのである。Then, the narrow band receiver extracts the frequency component of the trailing edge of the received signal and outputs it to the signal selector. Also,
The pulse compression receiver performs a pulse compression process on the received signal and outputs it to a signal selector. As is well known, a pulse compression receiver cannot detect a target during a transmission signal transmission period, that is, within a transmission pulse width. Therefore, in the signal selector,
Since the output of the narrow band receiver is selected at the time of short-distance target reception from the time of transmission signal transmission to the lapse of a predetermined time, and after the lapse of a predetermined time, the output of the pulse compression receiver is selected and time-synthesized and output. is there.
以上要するに、長パルス幅の受信信号から短パルスの
受信信号を形成し、これによって従前の長／短パルス複
合方式のものと同等の作用を行わせるのである。このと
き、本発明では、従来のように短パルスの送受信を行う
のではないから、従来の如き擬像の問題は解消され、ま
た装置構成の簡素化を図れることになる。In short, a short-pulse reception signal is formed from a long-pulse width reception signal, and thereby an operation equivalent to that of the conventional long / short-pulse combined system is performed. At this time, according to the present invention, transmission and reception of short pulses are not performed as in the related art, so that the problem of the pseudo image as in the related art is solved and the configuration of the apparatus can be simplified.
（実 施 例） 以下、本発明の実施例を図面を参照して説明する。Hereinafter, embodiments of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例に係るパルス圧縮レーダ装
置を示す。なお、第３図と同一構成部分には同一符号を
付してある。FIG. 1 shows a pulse compression radar apparatus according to one embodiment of the present invention. The same components as those in FIG. 3 are denoted by the same reference numerals.
本発明のパルス圧縮レーダ装置は、アンテナ１と、サ
ーキュレータ２と、信号分配器３と、狭帯域受信機４
と、信号選択器５と、パルス圧縮受信機７と、長パルス
送信機８とで基本的に構成される。The pulse compression radar device according to the present invention includes an antenna 1, a circulator 2, a signal distributor 3, and a narrow band receiver 4.
, A signal selector 5, a pulse compression receiver 7, and a long pulse transmitter 8.
長パルス送信機８が所定の繰り返し周期で出力する周
波数変調の施された長パルス幅の送信信号はサーキュレ
ータ２を介してアンテナ１から空間に放射され（第２図
（１））、目標で反射されて再びアンテナ１で受信され
る。受信された信号はサーキュレータ２を通り信号分配
器３で２分割され、一方は狭帯域受信機４へ、他方はパ
ルス圧縮受信機７へ入力される。A long-pulse-width transmission signal that has been subjected to frequency modulation and output by the long-pulse transmitter 8 at a predetermined repetition period is radiated into space from the antenna 1 via the circulator 2 (FIG. 2 (1)) and reflected at the target. The signal is received by the antenna 1 again. The received signal passes through a circulator 2 and is split into two by a signal distributor 3, one of which is input to a narrowband receiver 4 and the other is input to a pulse compression receiver 7.
狭帯域受信機４は、周波数変調の施された長パルス幅
の受信信号の後縁部分の周波数成分を取り出す帯域フィ
ルタを有し、第２図（２）（３）に示すように、連続的
に入力して来る各長パルス受信信号の後縁部から細いパ
ルスが、送信信号送出時から所定時間経過時まで次々に
形成されそれが信号選択器５に出力される。The narrow-band receiver 4 has a band-pass filter for extracting the frequency component of the trailing edge portion of the frequency-modulated received signal having a long pulse width, and as shown in FIGS. The narrow pulses are successively formed from the trailing edge of each long pulse reception signal input to the signal selector 5 until a predetermined time elapses from the transmission of the transmission signal, and are output to the signal selector 5.
一方、パルス圧縮受信機７では、１つの長パルス幅の
受信信号を受けてパルス圧縮処理をし１つの短パルスを
形成するから、第２図（４）に示すように先頭の受信信
号のパルス幅分の時間経過後から短パルスを出力し以後
それが重なるように連続的に出力される。On the other hand, the pulse compression receiver 7 receives one long pulse width received signal and performs pulse compression processing to form one short pulse. Therefore, as shown in FIG. Short pulses are output after a lapse of the time corresponding to the width, and thereafter the pulses are continuously output so as to overlap.
つまり、パルス圧縮受信機７では、送信パルス幅内で
は目標検出が不可能であるから、信号選択器５では送信
信号送信時から所定時間経過時までの近距離目標受信時
には狭帯域受信機４の出力（ａ）を選択し所定時間経過
以後はパルス圧縮受信機７の出力（ｂ）を選択しそれら
を時間合成して出力する（第２図（５））。That is, since the pulse compression receiver 7 cannot detect the target within the transmission pulse width, the signal selector 5 uses the narrow band receiver 4 during the short-distance target reception from the transmission signal transmission to the lapse of a predetermined time. The output (a) is selected, and after a lapse of a predetermined time, the output (b) of the pulse compression receiver 7 is selected, time-synthesized and output (FIG. 2 (5)).
（発明の効果） 以上説明したように、本発明のパルス圧縮レーダ装置
によれば、長パルス送信信号についての受信信号から短
パルスを形成できるようにしたので、短パルス送受信が
なくても近距離目標の検出を行うことができる。ここ
に、短パルス送受信の機能を不要とした結果、従来問題
視されていた擬像をなくすことができ、また余分な送受
信タイミングを設定する煩雑さをなくすことができ、さ
らに装置の簡素化を図ることができる効果がある。(Effects of the Invention) As described above, according to the pulse compression radar apparatus of the present invention, short pulses can be formed from a received signal of a long pulse transmission signal, so that a short distance can be obtained without short pulse transmission / reception. Target detection can be performed. Here, as a result of eliminating the function of short pulse transmission / reception, it is possible to eliminate a virtual image which has been regarded as a problem in the past, to eliminate the complexity of setting extra transmission / reception timing, and to further simplify the apparatus. There is an effect that can be achieved.
第１図は本発明の一実施例に係るパルス圧縮レーダ装置
の構成ブロック図、第２図は各部の動作波形図、第３図
は従来例の構成ブロック図、第４図は各部の動作波形図
である。 １……アンテナ、２……サーキュレータ、３……信号分
配器、４……狭帯域受信機、５……信号選択器、６……
出力端子、７……パルス圧縮受信機、８……長パルス送
信機、９……受信用長／短パルス切替器、10……短パル
ス受信機、11……遅延線路、12……送信用長／短パルス
切替器、13……短パルス送信機、14……長／短パルス切
替信号の入力端子。FIG. 1 is a block diagram of a configuration of a pulse compression radar apparatus according to an embodiment of the present invention, FIG. 2 is an operation waveform diagram of each section, FIG. 3 is a configuration block diagram of a conventional example, and FIG. FIG. DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 ... Circulator, 3 ... Signal distributor, 4 ... Narrow band receiver, 5 ... Signal selector, 6 ...
Output terminal 7, pulse compression receiver, 8 long pulse transmitter, 9 long / short pulse switch for reception, 10 short pulse receiver, 11 delay line, 12 transmission Long / short pulse switch, 13 ... short pulse transmitter, 14 ... L / short pulse switching signal input terminal.
Claims (1)
号を用いるパルス圧縮レーダ装置において；受信信号を
２方向へ分配する信号分配器と；前記信号分配器の一方
の出力を受けて前記送信信号送出時から所定時間経過後
の目標検出が不可能な近距離目標受信領域に連続的に入
力する前記送信信号による受信信号の後縁部分の周波数
成分を抽出し前記後縁部分の時間幅に対応する狭パルス
として出力する狭帯域フィルタを有する狭帯域受信機
と；前記信号分配器の他方の出力を受けてパルス圧縮処
理を施すパルス圧縮受信機と；送信信号の長パルス幅に
基づいて前記近距離目標受信領域に対応した所定時間経
過時までの近距離目標受信時には前記狭帯域受信機の出
力する狭パルスを選択し所定時間経過以後は前記パルス
圧縮受信機を出力を選択しそれらを時間軸上で合成して
出力する信号選択器と；を備えることを特徴とするパル
ス圧縮レーダ装置。1. A pulse compression radar system using a frequency-modulated transmission signal having a long pulse width; a signal distributor for distributing a received signal in two directions; Extracting the frequency component of the trailing edge of the reception signal by the transmission signal continuously input to the short-distance target reception area where the target cannot be detected after the elapse of a predetermined time from the transmission signal transmission time, and extracting the time width of the trailing edge A narrow-band receiver having a narrow-band filter that outputs as a narrow pulse corresponding to the following: a pulse-compression receiver that receives the other output of the signal distributor and performs a pulse compression process; based on a long pulse width of a transmission signal At the time of short-distance target reception until a predetermined time corresponding to the short-distance target reception area, a narrow pulse output from the narrow-band receiver is selected, and after the predetermined time elapses, the pulse compression receiver is output. Pulse compression radar apparatus characterized by comprising;-option and a signal selector for outputting the synthesized them in time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63040428A JP2652950B2 (en) | 1988-02-23 | 1988-02-23 | Pulse compression radar device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63040428A JP2652950B2 (en) | 1988-02-23 | 1988-02-23 | Pulse compression radar device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01214788A JPH01214788A (en) | 1989-08-29 |
| JP2652950B2 true JP2652950B2 (en) | 1997-09-10 |
Family
ID=12580380
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63040428A Expired - Lifetime JP2652950B2 (en) | 1988-02-23 | 1988-02-23 | Pulse compression radar device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2652950B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2784147B2 (en) * | 1994-07-29 | 1998-08-06 | 日本アンテナ株式会社 | Antenna shared circuit |
| JP3500580B2 (en) * | 2001-08-15 | 2004-02-23 | 財団法人資源探査用観測システム研究開発機構 | Radar equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5093088A (en) * | 1973-12-18 | 1975-07-24 |
-
1988
- 1988-02-23 JP JP63040428A patent/JP2652950B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01214788A (en) | 1989-08-29 |
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