JP2908170B2 - Direction measurement device - Google Patents
Direction measurement deviceInfo
- Publication number
- JP2908170B2 JP2908170B2 JP6360993A JP6360993A JP2908170B2 JP 2908170 B2 JP2908170 B2 JP 2908170B2 JP 6360993 A JP6360993 A JP 6360993A JP 6360993 A JP6360993 A JP 6360993A JP 2908170 B2 JP2908170 B2 JP 2908170B2
- Authority
- JP
- Japan
- Prior art keywords
- phase difference
- output
- azimuth
- signal
- time difference
- 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 - Lifetime
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- Measuring Phase Differences (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Description
【０００１】[0001]
【産業上の利用分野】この発明は方位測定装置に関し、
特にパルス変調されたＲＦ信号の到来方位を測定する装
置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azimuth measuring device,
In particular, the present invention relates to an apparatus for measuring the direction of arrival of a pulse-modulated RF signal.
【０００２】[0002]
【従来の技術】図５は例えば、James Bao-Yen Tsui著"M
ICROWAVE RECEIVERS WITH ELECTRONICWARFARE APPLICAT
ION ", 1986 John Wiley & Sons社，p.101 Figure 3,
16 に示された従来の方位測定装置を示す図であり、図
において、１ａ〜１ｄはアンテナ、２ａ〜２ｃは各アン
テナ１ａ〜１ｄ間の位相差を検出するための位相差測定
器である。2. Description of the Related Art FIG. 5 shows, for example, "M" by James Bao-Yen Tsui.
ICROWAVE RECEIVERS WITH ELECTRONICWARFARE APPLICAT
ION ", 1986 John Wiley & Sons, p.101 Figure 3,
FIG. 16 is a diagram showing the conventional azimuth measuring device shown in FIG. 16, where 1a to 1d denote antennas and 2a to 2c denote phase difference measurement for detecting a phase difference between the antennas 1a to 1d. It is a vessel.
【０００３】次に動作について説明する。パルス変調さ
れたＲＦ信号がアンテナ１ａ〜１ｄのアレイ平面に対し
θの角度で入射すると、各アンテナ間に光路差が生ず
る。ここでアンテナ１ａと１ｂを例にとり、これらアン
テナ１ａ，１ｂ間の距離をｄとすると、 光路差＝ｄｓｉｎθ の関係となる。そしてアンテナ１ａと１ｂとに入射した
ＲＦ信号の位相差を位相差測定器２ａで測定すると、光
路差に応じて、Next, the operation will be described. When the pulse-modulated RF signal enters the array plane of the antennas 1a to 1d at an angle of θ, an optical path difference occurs between the antennas. Here, taking the antennas 1a and 1b as an example, and assuming that the distance between these antennas 1a and 1b is d, the relationship of the optical path difference = d sin θ is obtained. And incident on the antennas 1a and 1b .
When the phase difference of the RF signal is measured by the phase difference measuring device 2a, according to the optical path difference,
【０００４】[0004]
【数１】 (Equation 1)
【０００５】なる出力が得られる。これは、位相差測定
器２ａが出力する位相差が、アンテナ１ａ、及び１ｂに
入力するＲＦ信号の位相差を２πで割った余りの値であ
ることを示す式であるので、この位相差測定器２ａの出
力の範囲は０以上２π未満となる。したがって位相差測
定器２ａは、例えば、アンテナ１ａ、及び１ｂに入力し
たＲＦ信号の位相差がπである場合に位相差をπと出力
するが、アンテナ１ａ、及び１ｂに入力したＲＦ信号の
位相差が実際には３πである場合でも位相差をπと出力
するように、異なる入射角（到来角）θでアンテナ１
ａ、及び１ｂに入力したＲＦ信号の位相差を、同一の位
相差として出力してしまう場合がある。そこで、この図
の例では、アンテナ１ａを基準とするアンテナ間距離を
ｄ，２ｄ，４ｄとし、お互いの位相差の関係から、測定
結果（位相差）に含まれる上述のようなあいまいさ（ア
ンビギュイティ：Ambiguity)を取除く仕組みとなってい
る。[0005] The following output is obtained. This is the phase difference measurement
The phase difference output from the antenna 2a is applied to the antennas 1a and 1b.
The remainder of the phase difference of the input RF signal divided by 2π
This is an expression indicating that the output of the phase difference measuring device 2a is
The range of the force is not less than 0 and less than 2π. Therefore, the phase difference measurement
The measuring device 2a is, for example, input to the antennas 1a and 1b.
When the phase difference of the RF signal is π, the phase difference is output as π.
Of the RF signals input to the antennas 1a and 1b
Even when the phase difference is actually 3π, the phase difference is output as π
As to the antenna 1 at different angles of incidence (angle of arrival) theta
a, and the phase difference between the RF signal input to 1b, in some cases output as the same phase difference. Therefore, in the example of this figure, the inter-antenna distances with respect to the antenna 1a are d, 2d, and 4d, and the above-described ambiguity (ambience) included in the measurement result (phase difference) is determined from the relationship between the phase differences. Guity (Ambiguity) is removed.
【０００６】[0006]
【発明が解決しようとする課題】従来の方位測定装置は
以上のように構成されているので、アンテナ及び位相検
波器共に複数個必要となり、複雑な装置構成となるとい
う問題点があった。また従来、例えば特開平３−５９４
８１号公報に示されるように、一対のアンテナを用い、
これらアンテナに入力する信号の到来時間差から信号の
到来方向を求めるようにしたものがあるが、この構成で
は到達時間差の測定精度の問題等からあまり正確な到来
角を測定することができないという問題点があった。Since the conventional azimuth measuring apparatus is constructed as described above, a plurality of antennas and a plurality of phase detectors are required, resulting in a problem that the apparatus has a complicated structure. Conventionally, for example, Japanese Patent Application Laid-Open No. 3-594
As shown in JP 81, using a pair of antennas,
There is a method in which the direction of arrival of a signal is obtained from the time difference of arrival of signals input to these antennas. However, this configuration cannot measure the angle of arrival very accurately due to the problem of measurement accuracy of the time difference of arrival. was there.
【０００７】この発明は上記のような問題点を解消する
ためになされたもので、簡単な装置構成でアンビギュイ
ティのない精度の高い方位測定ができる方位測定装置を
得ることを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide an azimuth measuring apparatus capable of performing highly accurate azimuth measurement without ambiguity with a simple apparatus configuration.
【０００８】[0008]
【課題を解決するための手段】この発明に係る方位測定
装置は、信号の位相差を測定する位相差測定手段と、信
号の到来時間差を測定する時間差測定手段と、上記位相
差及び到来時間差とから上記信号の到来方位を演算する
方位演算手段とを備えたものである。An azimuth measuring apparatus according to the present invention comprises a phase difference measuring means for measuring a phase difference of a signal, a time difference measuring means for measuring a time difference of arrival of a signal, and the phase difference and the time difference of arrival. And an azimuth calculating means for calculating the arrival azimuth of the signal.
【０００９】[0009]
【作用】この発明においては、位相差測定手段の出力
は、アンテナに入力する信号の位相差を２πで割った余
りの値であり、その範囲は０以上２π未満となるが、時
間差測定手段でアンテナ間の信号の到来時間差を測定
し、その時間差を用いることにより、位相差測定手段が
０以上２π未満の範囲で出力する位相差が実際には何周
期回っているものであるのかを判断してアンビギュイテ
ィを取除くようにしたから、一対のアンテナでアンビギ
ュイティのない高精度な方位測定を行うことができる。According to the present invention, the output of the phase difference measuring means is provided.
Is the remainder obtained by dividing the phase difference of the signal input to the antenna by 2π.
The range is from 0 to less than 2π.
Measures the arrival time difference of the signal between antennas by the difference measurement means
And, by Rukoto using the time difference, the phase difference measuring means
Since the phase difference output in the range from 0 to less than 2π actually been to remove the ambiguity by determining whether are those turning what period, high no ambiguity in the pair of antennas Accurate azimuth measurement can be performed.
【００１０】[0010]
【実施例】実施例１． 以下、この発明の一実施例を図について説明する。図１
において、１ａ，１ｂはアンテナ、２はこれら一対のア
ンテナ１ａ，１ｂ間の位相差を検出する位相差測定器、
３は上記一対のアンテナに到来するＲＦ信号の時間差を
検出する時間差測定器、４は上記位相差と時間差とから
ＲＦ信号の到来方位を演算する方位演算装置である。[Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings. FIG.
Wherein 1a and 1b are antennas, 2 is a phase difference measuring device for detecting a phase difference between the pair of antennas 1a and 1b,
Reference numeral 3 denotes a time difference measuring device for detecting a time difference between the RF signals arriving at the pair of antennas, and reference numeral 4 denotes an azimuth calculation device for calculating the azimuth of arrival of the RF signal from the phase difference and the time difference.
【００１１】次に動作について説明する。パルス変調さ
れたＲＦ信号がアンテナ１ａ，１ｂのアレイ面に対しθ
の角度で入射すると、図２に示すように、位相差φ及び
時間差τが生ずる。この位相差φ及び時間差τを、それ
ぞれ位相差測定器２及び時間差測定器３で測定する。位
相差測定器２の測定する位相差φについては前述のとお
り、Next, the operation will be described. The pulse-modulated RF signal is θ with respect to the array surface of the antennas 1a and 1b.
When incident at an angle, as shown in FIG. 2, is generated a phase difference φ及 beauty time difference tau. This phase difference φ and time difference τ are
The measurement is performed by the phase difference measuring device 2 and the time difference measuring device 3, respectively. Rank
The phase difference φ measured by the phase difference measuring device 2 is as described above.
【００１２】[0012]
【数２】 (Equation 2)
【００１３】であり、これは、位相差測定器２が出力す
る位相差φが、アンテナ１ａ，１ｂに入射するＲＦ信号
の位相差を２πで割った余りの値であることを示す式で
あるので、この位相差測定器２が出力する位相差φの範
囲は０≦φ＜２πとなる。また、時間差測定器３の測定
する時間差については、 This is the output of the phase difference measuring device 2.
The phase difference φ is the RF signal incident on the antennas 1a and 1b.
Is the remainder of dividing the phase difference by 2π
Therefore, the range of the phase difference φ output from the phase difference measuring device 2 is
The range is 0 ≦ φ <2π. In addition, measurement of the time difference measuring device 3
About the time difference
【００１４】[0014]
【数３】 (Equation 3)
【００１５】となる。そして位相差測定器２の出力した
位相差φと、時間差測定器３の出力した時間差τとを、
以下の関係式に用いると、方位演算装置４で方位θを決
定することができる。## EQU1 ## Then the <br/> phase difference φ which is the output of the phase difference measuring device 2, and an output time difference in the time between the difference measuring instrument 3 tau,
With the following equation, it is possible to determine the azimuth θ in azimuth calculation unit 4.
【００１６】[0016]
【数４】 (Equation 4)
【００１７】このように本実施例によれば、一対のアン
テナ１ａ，１ｂを用い、該アンテナに入力するＲＦ信号
の位相差及び時間差を検出し、方位演算装置４で、位相
差測定器２から０≦φ＜２πの範囲で出力される位相差
φが実際には何周期回転しているものであるのかを、時
間差測定器３から出力される時間差τを用いて判断して
アンビギュイティを取り除くようにしたから、１対のア
ンテナでも正確にアンビギュイティを取り除くことがで
き、装置を構成するアンテナ及び位相差測定器の数を減
らすことができ、装置の構成を簡略化することができ
る。According to this embodiment, a pair of antennas 1a, 1b, and detects the phase difference and the time difference between the RF signal input to the antenna, the azimuth arithmetic unit 4, the phase
Phase difference output from the difference measuring device 2 in the range of 0 ≦ φ <2π
whether φ is the one that has you doing periodic rotation in fact, when
Since the ambiguity is removed by using the time difference τ output from the difference measuring device 3, the ambiguity can be accurately removed even with a pair of antennas. The number of difference measuring devices can be reduced, and the configuration of the device can be simplified.
【００１８】実施例２． 次に本発明の第２の実施例による方位測定装置を図につ
いて説明する。上記実施例１では、位相差測定器２から
０≦φ＜２πの範囲で出力される位相差φが実際には何
周期回転しているものであるのかを、時間差測定器３か
ら出力される時間差τを用いて判断し、方位θを求める
ようにしたが、本実施例２では、図３に示すように、上
記実施例１の方位測定装置に、時間差測定器３の出力の
みを受ける粗測用の方位演算装置５を設け、この粗測用
の方位演算装置５から時間差τだけを用いた粗測用の出
力を出力し、精測が必要な場合のみ、上記実施例１と同
様に、位相差φと時間差τとを用いて測定する精測用の
出力を、位相差測定器２と、時間差測定器３との両出力
を受ける精測用の方位演算装置４から出力するようにし
たものである。ここで、粗測用の方位演算装置５は、時
間差測定器３で測定する時間差τを、以下の関係式に用
いて、方位θを求めるものである。 Embodiment 2 FIG. Next, an azimuth measuring apparatus according to a second embodiment of the present invention will be described with reference to the drawings. In the first embodiment, the phase difference measuring device 2
What is the actual phase difference φ output in the range of 0 ≦ φ <2π
The time difference measurement device 3 checks whether the object is rotating periodically.
Value, using the time difference τ is et outputted, has been to seek direction theta, in the second embodiment, as shown in FIG. 3, above
For the azimuth measurement device of the serial Example 1, provided the azimuth calculation device 5 for measuring crude receiving only the output of the time difference measuring device 3, measuring roughness of this
The output for coarse measurement using only the time difference τ is output from the azimuth calculation device 5 of FIG.
As the output for measuring fine be measured with a phase difference φ and the time difference tau, and a phase difference measuring device 2, and outputs the azimuth calculation unit 4 for measuring fine receiving both outputs of the time difference measuring device 3 It is like that. Here, the direction calculation device 5 for rough measurement is
The time difference τ measured by the difference measuring device 3 is used in the following relational expression.
To obtain the azimuth θ.
【数５】 この実施例では、粗測のみでよい場合には周波数（波
長）の情報が必要でないという利点がある。(Equation 5) In this embodiment, the frequency (wave)
There is an advantage that the information of (C) is not required.
【００１９】実施例３．次に本発明の第３の実施例によ
る方位測定装置を図について説明する。図４において、
６ａ，６ｂはアンテナ１ａ，１ｂと位相差測定器２及び
時間差測定器３との間に配置され、該アンテナに入力さ
れる信号を所定の周波数の信号に逓降し、その逓降した
信号を位相差測定器２に入力するとともに、その検波出
力を時間差測定器３に入力するようにしたスーパーヘテ
ロダイン受信機である。Embodiment 3 FIG. Next, an azimuth measuring apparatus according to a third embodiment of the present invention will be described with reference to the drawings. In FIG.
Reference numerals 6a and 6b are arranged between the antennas 1a and 1b and the phase difference measuring device 2 and the time difference measuring device 3, respectively, downconvert a signal input to the antenna into a signal of a predetermined frequency, and convert the downconverted signal. This is a superheterodyne receiver in which the detection output is input to the phase difference measuring device 2 and the detection output is input to the time difference measuring device 3.
【００２０】次に動作について説明する。アンテナ１
ａ，１ｂに入力したＲＦ信号はスーパーヘテロダイン受
信機６ａ，６ｂに入力され、ここでＩＦ（中間周波数）
信号に周波数変換（逓降）され、該周波数変換されたＩ
Ｆ信号は位相差測定器２においてそのＩＦ信号の位相差
が検出される。またスーパーヘテロダイン受信機６ａ，
６ｂの検波出力は時間差測定器３に入力されてその時間
差が測定され、方位演算装置４にてこれら位相差及び時
間差から入射角θが求められる。Next, the operation will be described. Antenna 1
The RF signals input to a and 1b are input to superheterodyne receivers 6a and 6b, where they are IF (intermediate frequency).
The signal is frequency-converted (down-converted) and the frequency-converted I
The phase difference of the IF signal of the F signal is detected by the phase difference measuring device 2. Also, the superheterodyne receiver 6a,
The detection output of 6b is input to the time difference measuring device 3 to measure the time difference, and the azimuth calculating device 4 calculates the incident angle θ from the phase difference and the time difference.
【００２１】このように本実施例３ではスーパーヘテロ
ダイン受信器６ａ，６ｂを設け、所定のＲＦ信号にチュ
ーニングをして位相差を測定することにより、受信感度
が上がり、目的の信号のみの方位測定を行うことができ
るという利点がある。As described above, in the third embodiment, the superheterodyne receivers 6a and 6b are provided, and a predetermined RF signal is tuned to measure a phase difference, thereby increasing the receiving sensitivity and measuring the azimuth of only the target signal. There is an advantage that can be performed.
【００２２】[0022]
【発明の効果】以上のように、この発明に係る方位測定
装置によれば、位相差測定手段によって信号の位相差を
測定し、時間差測定手段によって信号の到来時間差を測
定し、これら位相差及び到来時間差から上記信号の到来
方位を演算するようにしたから、１対のアンテナで高精
度な方位測定が可能となり、装置を簡素で安価なものと
することができる効果がある。As described above, according to the azimuth measuring apparatus according to the present invention, the phase difference of the signal is measured by the phase difference measuring means, and the arrival time difference of the signal is measured by the time difference measuring means. Since the arrival direction of the signal is calculated based on the arrival time difference, highly accurate orientation measurement can be performed with a pair of antennas, which has the effect of making the apparatus simple and inexpensive.
【図１】この発明の第１の実施例による方位測定装置を
示す図である。FIG. 1 is a diagram showing an azimuth measuring device according to a first embodiment of the present invention.
【図２】アンテナ１ａとアンテナ１ｂの入力信号の関係
を示す図である。FIG. 2 is a diagram showing a relationship between input signals of an antenna 1a and an antenna 1b.
【図３】この発明の第２の実施例による方位測定装置を
示す図である。FIG. 3 is a diagram showing an azimuth measuring device according to a second embodiment of the present invention.
【図４】この発明の第３の実施例による方位測定装置を
示す図である。FIG. 4 is a diagram showing an azimuth measuring device according to a third embodiment of the present invention.
【図５】従来の方位測定装置を示す図である。FIG. 5 is a diagram showing a conventional direction measurement device.
１ａ，１ｂ アンテナ ２ 位相差測定器 ３ 時間差測定器 ４ 方位演算装置 ５ 方位演算装置（粗測用） ６ａ，６ｂ スーパーヘテロダイン受信機（周波数逓降
手段）1a, 1b Antenna 2 Phase difference measuring device 3 Time difference measuring device 4 Azimuth calculation device 5 Azimuth calculation device (for coarse measurement) 6a, 6b Superheterodyne receiver (frequency step-down means)
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平４−212081（ＪＰ，Ａ) 特開 平５−157823（ＪＰ，Ａ) 特開 平５−215831（ＪＰ，Ａ) 特開 平２−205787（ＪＰ，Ａ) 特開 平３−59481（ＪＰ，Ａ) 特開 平４−168388（ＪＰ，Ａ) 特開 昭63−196875（ＪＰ，Ａ) 特開 平２−61576（ＪＰ，Ａ) 実開 平４−106772（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.6，ＤＢ名) G01S 3/00 - 3/74 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-212081 (JP, A) JP-A-5-157823 (JP, A) JP-A-5-215831 (JP, A) JP-A-2- 205787 (JP, A) JP-A-3-59481 (JP, A) JP-A-4-168388 (JP, A) JP-A-63-196875 (JP, A) JP-A-2-61576 (JP, A) JP-U 4-106772 (JP, U) (58) Field surveyed (Int. Cl. 6 , DB name) G01S 3/00-3/74
Claims (3)
ナと、 該アンテナに入力する信号の位相差を２πで割った余り
の値を位相差として出力する位相差測定手段と、 上記アンテナに入力する信号の到来時間差を測定する時
間差測定手段と、 上記位相差測定手段が出力する位相差が、何周期回転し
ているものであるのかを、上記時間差測定手段の出力す
る到来時間差を用いて判断し、上記信号の到来方位を演
算する方位演算手段とを備えたことを特徴とする方位測
定装置。1. A pair of antennas provided at a predetermined interval and a remainder obtained by dividing a phase difference between signals input to the antennas by 2π.
Phase difference measuring means for outputting the value of the phase difference as a phase difference, time difference measuring means for measuring the arrival time difference of the signal input to the antenna, and how many cycles the phase difference output by the phase difference measuring means rotates.
Whether the ones are, to the output of said time difference measuring means
And a direction calculating means for determining the direction of arrival of the signal by using the arrival time difference .
の概略的な到来方向を測定する粗測用方位演算手段を設
け、この粗測用方位演算手段の出力と上記方位演算手段
の出力とを選択して出力させるようにしたことを特徴と
する請求項第１項記載の方位測定装置。2. The method according to claim 1, wherein said signal is obtained from an output of said time difference measuring means.
Azimuth calculation means for measuring the approximate direction of arrival
The output of the coarse measurement azimuth calculation means and the azimuth calculation means
2. The azimuth measuring device according to claim 1 , wherein said output is selected and output .
降し、該逓降された信号を上記位相差測定手段に入力す
るとともに、その検波出力を上記時間差測定手段に入力
する周波数逓降手段を備えたことを特徴とする方位測定
装置。3. The azimuth measuring device according to claim 1, wherein the signal input to the antenna is down-converted to a signal of a predetermined frequency, and the down-converted signal is input to the phase difference measuring means. An azimuth measuring device comprising frequency down-converting means for inputting a detection output to the time difference measuring means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6360993A JP2908170B2 (en) | 1993-03-23 | 1993-03-23 | Direction measurement device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6360993A JP2908170B2 (en) | 1993-03-23 | 1993-03-23 | Direction measurement device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06273504A JPH06273504A (en) | 1994-09-30 |
| JP2908170B2 true JP2908170B2 (en) | 1999-06-21 |
Family
ID=13234212
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6360993A Expired - Lifetime JP2908170B2 (en) | 1993-03-23 | 1993-03-23 | Direction measurement device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2908170B2 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004082171A1 (en) | 2003-03-11 | 2004-09-23 | Fujitsu Limited | Radio device |
| JP2006329671A (en) * | 2005-05-23 | 2006-12-07 | Mitsubishi Electric Corp | Incident angle deducing device |
| JP5031226B2 (en) * | 2005-11-01 | 2012-09-19 | 株式会社日本自動車部品総合研究所 | Object position detection device |
| JP5309569B2 (en) | 2008-01-11 | 2013-10-09 | ソニー株式会社 | Direction detection system |
| JP2011058836A (en) | 2009-09-07 | 2011-03-24 | Alps Electric Co Ltd | Wireless sensor device |
| JP6373222B2 (en) * | 2015-04-03 | 2018-08-15 | 三菱電機株式会社 | Direction detection apparatus and direction detection method |
| US10416269B2 (en) * | 2017-04-20 | 2019-09-17 | Raytheon Company | Disambiguated direction finding |
| US10422847B2 (en) * | 2017-04-20 | 2019-09-24 | Raytheon Company | Interferometric time delay of arrival |
-
1993
- 1993-03-23 JP JP6360993A patent/JP2908170B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06273504A (en) | 1994-09-30 |
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