CN102288946A - Distance measuring defuzzification method for pseudo-random code phase modulation continuous-wave radar - Google Patents

Abstract

The invention discloses a distance measuring defuzzification method for a pseudo-random code phase modulation continuous-wave radar, which is used for measuring a target distance in the field of continuous-wave radars. In the method, phase modulation is performed on carrier waves alternatively on circles by using a stagger pseudo code, and distance fuzzy resolution is performed by using a target distance remainder of two adjacent circles obtained by measuring, so that the real distance of a target can be determined. The method can replace the conventional pseudo code real-time alternate measuring method, and the detection and processing performance of the radar can be enhanced.

Description

A kind of pseudo-random code phase modulating continuous wave radar range finding ambiguity solution method

Technical field

The present invention relates to a kind of method that is used to resolve target range in continuous wave pseudorandomcode modulation field of radar, be specially adapted to the range observation of miniaturization pseudo-random code modulated continuous wave radar.

Background technology

At present, at home and abroad adopt in the pseudo-random code modulated continuous wave radar primary radar in measuring period irregular sign indicating number alternately the mode of emission carry out target range and resolve, this distance measuring method has been sacrificed Measuring Time over half, and because this alternately the measurement in real time upset the continuity that signal receives, feasible further signal Processing, can't carry out as sliding window disposal route, influence the performance of radar.

Summary of the invention

Problem to be solved by this invention is exactly to have proposed a kind of irregular sign indicating number is alternately taken turns method by circle distance-finding method, this method can replace traditional real-time alternately measuring method, and because this alternate cycle is carried out according to radar scanning one circle, the Radar Signal Processing time is compared classic method has like this increased by one times, and signal to noise ratio (S/N ratio) improves 3dB.Simultaneously because in the radar scanning process, the signal that receives is continuous, can carry out further signal Processing.

Problem to be solved by this invention is achieved in that

A kind of pseudo-random code phase modulating continuous wave radar range finding ambiguity solution method may further comprise the steps:

(1) continuous wave radar adopt the different pseudo-code of two groups of clock frequencies of a, b by the radar scanning circle alternately wheel send out, each scanning circle circulation is continuously sent out one group of pseudo-code, sends out an a group pseudo-code when the m circle, then the m+1 circle is sent out a b group pseudo-code, m is a natural number, represents the current scanning number of turns;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: apart from remainder, orientation, pitching, radial velocity and Measuring Time, be labeled as respectively Δ R, A, E,

And t;

(3) distance parameter that utilizes the two adjacent groups pseudo-code to measure carries out fuzzy distance and resolves; With the corresponding timeslice in sector is unit, and adjacent turn matches, and is used for the range finding ambiguity solution of this circle behind the preceding circle ranging data buffer memory;

(4) judgement of same target: utilize radar to be t in m circle, the moment _m, the parameter of the target location that radar detection obtains, radial velocity, radial velocity direction, prediction is t in m+1 circle, the moment _M+1Survey position, speed, the direction of same target; Utilize the ripple door relation of time, position, radial velocity, direction, in a plurality of Targets Dots, determine to belong to same target Ben Quan and on the echo data incidence relation of a circle;

(5) the target echo data to being associated are got a, and two groups of pseudo-codes of b fuzzy distance remainder separately add integral multiple fuzzy distance separately, obtain a, each self-corresponding N distance of two groups of pseudo-codes of b with:

(a code distance and);

(b code distance and);

In the formula: i, j=0,1 ..., N;

Δ R _aMeasure during for emission a group pseudo-code apart from remainder;

Δ R _bMeasure during for emission b group pseudo-code apart from remainder;

R _ModaNo fuzzy distance for the covering of a group pseudo-code;

R _ModbNo fuzzy distance for the covering of b group pseudo-code;

For utilizing all potential ranges at the target place that a group pseudo-code calculates;

For utilizing all potential ranges at the target place that b group pseudo-code calculates;

(6) get time unifying, to two groups of distances and Do the extrapolation distance alignment, and get difference:

Δt＝t _m+1-t _m；

${\mathrm{\Δd}}_{\mathrm{ij}}=|{\hat{R}}_{\mathrm{bj}}-({\hat{R}}_{\mathrm{ai}}+\mathrm{\Δt}\×({\stackrel{\·}{R}}_a+{\stackrel{\·}{R}}_b)/2)|;$

In the formula: i, j=0,1 ..., N;

Δ t is the mistiming of adjacent twice measurement;

The target velocity that measures during for emission a group pseudo-code;

The target velocity that measures during for emission b group pseudo-code;

Δ d _IjFor utilizing the difference of the target potential range that two groups of pseudo-codes of a, b calculate respectively;

(7) as difference DELTA d _Ij≤ 3 σ _R, σ wherein _RThe range observation error promptly satisfies the distance error compression context, and then Dui Ying i, j are the fuzzy number of target actual distance correspondence, is designated as m, n, and the distance of target just can be expressed as:

R=m * R _Moda+ Δ R _aOr

R＝n×R _modb+ΔR _b；

In the formula: R is a target range;

Finishing target range resolves.

Wherein, the echo data correlating method of definite same target is divided into following 3 steps in the step (4):

401, the time correlation of target data is judged: if satisfy the time correlation condition, proceed the correlated judgment of next step;

The time correlation condition is:

$T-\frac{T}{K_T}\≤\mathrm{\Δt}\≤T+\frac{T}{K_T};$

Wherein: T, K _T, Δ t is respectively radar scanning cycle, target coefficient correlation time and target two circle admission time differences;

402, the orientation of target data, pitching correlated judgment:, proceed the correlated judgment of next step if satisfy orientation, pitching correlated condition;

Calculate orientation, pitching thresholding earlier:

The orientation thresholding: $G_{\mathrm{\αk}}=\frac{\mathrm{\Δt}\sqrt{v_{\max }^2-v_{\mathrm{rp}}^2}}{r_{\mathrm{pk}}}+k_{\mathrm{\α}}{\mathrm{\σ}}_{\mathrm{\α}};$

The pitching thresholding: $G_{\mathrm{\βk}}=\frac{\mathrm{\Δt}\sqrt{v_{\max }^2-v_{\mathrm{rp}}^2}}{r_{\mathrm{pk}}}+k_{\mathrm{\β}}{\mathrm{\σ}}_e;$

V wherein _Max, r _Pk, v _RpBe respectively target travel k maximal rate, radial distance, radial velocity constantly, σ _α, σ _eBe respectively orientation and luffing angle error, k _α, k _βBe respectively orientation and pitching thresholding coefficient;

Orientation, pitching correlated condition are:

| α _c-α _p|≤G _{α k}(orientation)

| e _c-e _p|≤G _{β k}(pitching)

α wherein _c, α _pBe respectively this a circle bearing data and a last circle bearing data;

e _c, e _pBe respectively this circle pitching data and last circle pitching data;

403, the radial velocity correlated judgment of target data:, then think same target if satisfy the radial velocity correlated condition;

The radial velocity correlated condition:

${\stackrel{\·}{R}}_m\×{\stackrel{\·}{R}}_{m+1}>0---\left(1\right)$

Simultaneously

In the formula:

Distinguish the radial velocity of corresponding target at m circle and m+1 circle,

Being the radial velocity dependent threshold, is the function of speed and distance; When radial velocity satisfies (1) and (2) formula simultaneously, then think

Radial velocity is relevant.

The present invention compares background technology and has the following advantages:

1. the processing time is compared classic method has increased by one times, and signal to noise ratio (S/N ratio) improves 3dB;

2. the signal that receives is continuous, can slide window formula signal Processing.

Embodiment

(1) continuous wave radar adopt the different pseudo-code of two groups of clock frequencies of a, b by the radar scanning circle alternately wheel send out, each scanning circle circulation is continuously sent out one group of pseudo-code, sends out an a group pseudo-code when the m circle, then the m+1 circle is sent out a b group pseudo-code, m is a natural number, represents the current scanning number of turns;

Among the embodiment, pseudo-code a clock frequency is elected 2.8MHz as, and pseudo-code b clock frequency is elected 3.1MHz as, the pseudo-code code length is elected 31 as, and the no fuzzy distance of pseudo-code a correspondence is: 1.66km, and the no fuzzy distance of pseudo-code b correspondence is: 1.5km, replace wheel by the scanning circle and send out sweep speed: 1 circle/second;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: apart from remainder, orientation, pitching, radial velocity and Measuring Time, be labeled as respectively Δ R, A, E,

And t;

Among the embodiment, suppose when moment 16s to send signaling a that target is 12km apart from the radar actual distance, heading be that close speed is 80m/s over against flight to radar, and the orientation is 87 °, and pitching is 6 °; If do not consider measuring error, the target component that measures when then launching pseudo-code a is: (0.38km, 87 °, 6 °, 80m/s, 16s);

(3) distance parameter that utilizes the two adjacent groups pseudo-code to measure carries out fuzzy distance and resolves; With the corresponding timeslice in sector is unit, and adjacent turn matches, and is used for the range finding ambiguity solution of this circle behind the preceding circle ranging data buffer memory;

Among the embodiment, at adjacent Shang Yiquan, promptly constantly send pseudo-code b during 15s, do not consider that the target component that measuring error measures when then launching pseudo-code b is: (0.80km, 87 °, 6 °, 80m/s, 15s), these data are saved, and are used for range ambiguity and resolve;

(4) judgement of same target: utilize radar to be t in m circle, the moment _m, the parameter of the target location that radar detection obtains, radial velocity, radial velocity direction, prediction is t in m+1 circle, the moment _M+1Survey position, speed, the direction of same target; Utilize the ripple door relation of time, position, radial velocity, direction, in a plurality of Targets Dots, determine to belong to same target Ben Quan and on the echo data incidence relation of a circle;

Among the embodiment, the target component of measuring during emission pseudo-code a is: (0.38km, 87 °, 6 °, 80m/s, 16s);

The target component of measuring during emission pseudo-code b is: (0.08km, 87 °, 6 °, 80m/s, 15s); Measured as can be seen position, radial velocity, direction parameter are identical, satisfy the data association relation, can think same target;

(5) the target echo data to being associated are got a, and two groups of pseudo-codes of b fuzzy distance remainder separately add integral multiple fuzzy distance separately, obtain a, each self-corresponding N distance of two groups of pseudo-codes of b with:

(a code distance and);

(b code distance and);

In the formula: i, j=0,1 ..., N;

Δ R _aMeasure during for emission a group pseudo-code apart from remainder;

Δ R _bMeasure during for emission a group pseudo-code apart from remainder;

R _ModaNo fuzzy distance for the covering of a group pseudo-code;

R _ModbNo fuzzy distance for the covering of b group pseudo-code;

For utilizing all potential ranges at the target place that a group pseudo-code calculates;

For utilizing all potential ranges at the target place that b group pseudo-code calculates;

Among the embodiment, calculate

${\hat{R}}_{a1}=1\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=1\×1.66+0.38=2.04\mathrm{km}$

${\hat{R}}_{a2}=2\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=2\×1.66+0.38=3.7\mathrm{km}$

${\hat{R}}_{a3}=3\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=3\×1.66+0.38=5.36\mathrm{km}$

${\hat{R}}_{a4}=4\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=4\×1.66+0.38=7.02\mathrm{km}$

${\hat{R}}_{a5}=5\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=5\×1.66+0.38=8.68\mathrm{km}$

${\hat{R}}_{a6}=6\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=6\×1.66+0.38=10.34\mathrm{km}$

${\hat{R}}_{a7}=7\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=7\×1.66+0.38=12\mathrm{km}$

${\hat{R}}_{a8}=8\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=8\×1.66+0.38=13.66\mathrm{km}$

${\hat{R}}_{a9}=9\×R_{\mathrm{mod}a}+{\mathrm{\ΔR}}_a=9\×1.66+0.38=15.32\mathrm{km}$

Calculate ${\hat{R}}_{\mathrm{bj}}:$

${\hat{R}}_{b1}=1\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=1\×1.5+0.08=1.58\mathrm{km}$

${\hat{R}}_{b2}=2\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=2\×1.5+0.08=3.08\mathrm{km}$

${\hat{R}}_{b3}=3\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=3\×1.5+0.08=4.58\mathrm{km}$

${\hat{R}}_{b4}=4\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=4\×1.5+0.08=6.08\mathrm{km}$

${\hat{R}}_{b5}=5\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=5\×1.5+0.08=7.58\mathrm{km}$

${\hat{R}}_{b6}=6\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=6\×1.5+0.08=9.08\mathrm{km}$

${\hat{R}}_{b7}=7\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=7\×1.5+0.08=10.58\mathrm{km}$

${\hat{R}}_{b8}=8\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=8\×1.5+0.08=12.08\mathrm{km}$

${\hat{R}}_{b9}=9\×R_{\mathrm{mod}b}+{\mathrm{\ΔR}}_b=9\×1.5+0.08=13.58\mathrm{km}$

(6) get time unifying, to two groups of distances and

Do the extrapolation distance alignment, and get difference:

Δt＝t _m+1-t _m；

${\mathrm{\Δd}}_{\mathrm{ij}}=|{\hat{R}}_{\mathrm{bj}}-({\hat{R}}_{\mathrm{ai}}+\mathrm{\Δt}\×({\stackrel{\·}{R}}_a+{\stackrel{\·}{R}}_b)/2)|;$

In the formula: i, j=0,1 ..., N;

Δ t is the mistiming of adjacent twice measurement;

The target velocity that measures during for emission a group pseudo-code;

The target velocity that measures during for emission b group pseudo-code;

Δ d _IjFor utilizing the difference of the target potential range that two groups of pseudo-codes of a, b calculate respectively.

Among the embodiment, calculate Δ d _Ij, it is as follows to be expressed as matrix form:

$\mathrm{\Δd}=\left|\begin{array}{ccccccccc}0.54& -0.96& -2.46& -3.96& -5.46& -6.96& -8.46& -9.96& -11.46\\ 2.2& 0.7& -0.8& -2.3& -3.8& -5.2& -6.7& -8.2& -9.7\\ 3.86& 2.36& 0.86& -0.64& -2.14& -3.64& -5.14& -6.64& -8.14\\ 5.52& 4.02& 2.52& 1.02& -0.48& -1.98& -3.48& -4.98& -6.48\\ 7.18& 5.68& 4.18& 2.68& 1.18& -0.32& -1.82& -3.32& -4.82\\ 8.84& 7.34& 5.84& 4.34& 2.84& 1.34& -0.16& -1.66& -3.16\\ 10.5& 9.0& 7.5& 6.0& 4.5& 3.0& 1.5& 0& -1.5\\ 12.16& 10.66& 9.16& 7.66& 6.16& 4.66& 3.16& 1.66& 0.16\\ 13.82& 12.32& 10.82& 9.32& 7.82& 6.32& 4.82& 3.32& 1.82\end{array}\right|$

(7) as difference DELTA d _Ij≤ 3 σ _R, σ wherein _RThe range observation error promptly satisfies the distance error compression context, and then Dui Ying i, j are the fuzzy number of target actual distance correspondence, is designated as m, n, and the distance of target just can be expressed as:

R=m * R _Moda+ Δ R _aOr

R＝n×R _modb+ΔR _b；

Among the embodiment, establish radargrammetry error σ _R=20m, Δ d then satisfies condition _Ij≤ 3 σ _RHave only:

Δd _ij＝0(i＝7，j＝8)

So have: m=7, n=8.

Target range can be calculated as follows:

R＝m×R _moda+ΔR _a＝7×1.66+0.38＝12km

Finishing target range resolves.

Claims (2)

1. pseudo-random code phase modulating continuous wave radar range finding ambiguity solution method may further comprise the steps:

(1) continuous wave radar adopt the different pseudo-code of two groups of clock frequencies of a, b by the radar scanning circle alternately wheel send out, each scanning circle circulation is continuously sent out one group of pseudo-code, sends out an a group pseudo-code when the m circle, then the m+1 circle is sent out a b group pseudo-code, m is a natural number, represents the current scanning number of turns;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: apart from remainder, orientation, pitching, radial velocity and Measuring Time, be labeled as respectively Δ R, A, E,

And t;

(3) distance parameter that utilizes the two adjacent groups pseudo-code to measure carries out fuzzy distance and resolves; With the corresponding timeslice in sector is unit, and adjacent turn matches, and is used for the range finding ambiguity solution of this circle behind the preceding circle ranging data buffer memory;

(4) judgement of same target: utilize radar to be t in m circle, the moment _m, the parameter of the target location that radar detection obtains, radial velocity, radial velocity direction, prediction is t in m+1 circle, the moment _M+1Survey position, speed, the direction of same target; Utilize the ripple door relation of time, position, radial velocity, direction, in a plurality of Targets Dots, determine to belong to same target Ben Quan and on the echo data incidence relation of a circle;

(5) the target echo data to being associated are got a, and two groups of pseudo-codes of b fuzzy distance remainder separately add integral multiple fuzzy distance separately, obtain a, each self-corresponding N distance of two groups of pseudo-codes of b with:

(a code distance and);

(b code distance and);

In the formula: i, j=0,1 ..., N;

Δ R _aMeasure during for emission a group pseudo-code apart from remainder;

Δ R _bMeasure during for emission b group pseudo-code apart from remainder;

R _ModaNo fuzzy distance for the covering of a group pseudo-code;

R _ModbNo fuzzy distance for the covering of b group pseudo-code;

For utilizing all potential ranges at the target place that a group pseudo-code calculates;

For utilizing all potential ranges at the target place that b group pseudo-code calculates;

(6) get time unifying, to two groups of distances and

Do the extrapolation distance alignment, and get difference:

Δt＝t _m+1-t _m；

In the formula: i, j=0,1 ..., N;

Δ t is the mistiming of adjacent twice measurement;

The target velocity that measures during for emission a group pseudo-code;

The target velocity that measures during for emission b group pseudo-code;

Δ d _IjFor utilizing the difference of the target potential range that two groups of pseudo-codes of a, b calculate respectively;

(7) as difference DELTA d _Ij≤ 3 σ _R, σ wherein _RThe range observation error promptly satisfies the distance error compression context, and then Dui Ying i, j are the fuzzy number of target actual distance correspondence, is designated as m, n, and the distance of target just can be expressed as:

R=m * R _Moda+ Δ R _aOr

R＝n×R _modb+ΔR _b；

In the formula: R is a target range;

Finishing target range resolves.

2. a kind of pseudo-random code phase modulating continuous wave radar range finding ambiguity solution method according to claim 1 is characterized in that: the echo data correlating method of determining same target in the step (4) is divided into following 3 steps:

401, the time correlation of target data is judged: if satisfy the time correlation condition, proceed the correlated judgment of next step;

The time correlation condition is:

Wherein: T, K _T, Δ t is respectively radar scanning cycle, target coefficient correlation time and target two circle admission time differences;

402, the orientation of target data, pitching correlated judgment:, proceed the correlated judgment of next step if satisfy orientation, pitching correlated condition;

Calculate orientation, pitching thresholding earlier:

The orientation thresholding:

The pitching thresholding:

V wherein _Max, r _Pk, v _RpBe respectively target travel k maximal rate, radial distance, radial velocity constantly, σ _α, σ _eBe respectively orientation and luffing angle error, k _α, k _βBe respectively orientation and pitching thresholding coefficient;

Orientation, pitching correlated condition are:

| α _c-α _p|≤G _{α k}(orientation)

| e _c-e _p|≤G _{β k}(pitching)

α wherein _c, α _pBe respectively this a circle bearing data and a last circle bearing data;

e _c, e _pBe respectively this circle pitching data and last circle pitching data;

403, the radial velocity correlated judgment of target data:, then think same target if satisfy the radial velocity correlated condition;

The radial velocity correlated condition:

Simultaneously

In the formula:

Distinguish the radial velocity of corresponding target at m circle and m+1 circle,

Being the radial velocity dependent threshold, is the function of speed and distance; When radial velocity satisfies (1) and (2) formula simultaneously, then think

Radial velocity is relevant.