CN103592645B - The fuzzy calculation method of a kind of pseudo-random code phase modulating continuous wave radar speed - Google Patents

Abstract

The invention discloses the fuzzy calculation method of a kind of pseudo-random code phase modulating continuous wave radar speed, it relates in continuous wave radar field and is used as to measure target velocity.It is that a kind of distance is not fuzzy, the method for designing of velocity ambiguity, adopts irregular pseudo-random code to carry out phase-modulation to carrier wave, and alternate wheel method, utilize the target velocity remainder measured for twice to carry out velocity ambiguity and resolve, thus the true velocity of target can be determined.This method ensure that range observation is unambiguous in radar range ability, thus radar can be improved to the detectivity of distant object by range segment separating target detection, can be reduced because of nearby by distance-sensitivity control method, the false-alarm that causes of sea clutter, raising radar in complex environment to the detectability of target at a slow speed.

Description

The fuzzy calculation method of a kind of pseudo-random code phase modulating continuous wave radar speed

Technical field

The present invention relates to a kind of method for solving target speed in continuous wave pscudo-random codc modulation field of radar, be specially adapted to the velocity survey of miniaturization pscudo-random codc modulation continuous wave radar.

Background technology

At present, Doppler's target detection system is adopted at home and abroad in pscudo-random codc modulation continuous wave radar, there is no velocity ambiguity, but range ambiguity is serious, its advantage is that detection perform is superior without clutter district in the detection zone that Doppler is higher, but in the detection zone of the Doppler end of compared with, clutter, target are often aliasing in together after distance is relevant, are difficult to distinguish.

Summary of the invention

To be solved by this invention be exactly in radar range ability distance not fuzzy, and the problem of velocity ambiguity, irregular pseudo-random code is adopted to carry out phase-modulation to carrier wave, and alternate wheel method, utilize the target velocity remainder measured for twice to carry out velocity ambiguity to resolve, thus the true velocity of target can be determined.This method ensure that range observation is unambiguous in radar range ability, thus radar can be improved to the detectivity of distant object by range segment separating target detection, can be reduced because of nearby by distance-sensitivity control method, the false-alarm that causes of sea clutter, raising radar in complex environment to the detectability of target at a slow speed.

For solving problem set forth above, the present invention proposes the fuzzy calculation method of a kind of pseudo-random code phase modulating continuous wave radar speed, comprising the following steps:

(1) pseudo-random code that radar employing a, b two groups of clock frequencies are different completes an alternate wheel and sends out in wave beam residence time;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: distance, orientation, speed remainder and measure the moment;

(3) judgement of same target: if the distance of target, orientation and measurement moment meet data correlation condition, be then same target;

Step (3) specifically comprises following three steps:

301, time correlation judges: if meet time correlation condition, proceed the correlated judgment of next step;

Time correlation condition is: T ₁-T ₂≤ Δ t;

Wherein: Δ t is the target measurement cycle;

T ₁for the target measurement moment in a group pseudo-random code measuring period;

T ₂for the target measurement moment in b group pseudo-random code measuring period;

302, orientation correlated judgment: if meet orientation correlated condition, proceed the correlated judgment of next step;

First calculate orientation thresholding:

Orientation thresholding: $G_A=\frac{\mathrm{\Δt}{v}_{\max }}{r_{\mathrm{pk}}}+k_A+{\mathrm{\σ}}_A;$

Wherein v _maxfor target travel maximal rate, Δ t is the target measurement cycle, σ _afor orientation angles error, k _abe respectively orientation threshold coefficient;

Orientation correlated condition is: | A ₁-A ₂|≤G _a

In formula: A ₁for the target side place value in a group pseudo-random code measuring period;

A ₂for the target side place value in b group pseudo-random code measuring period;

303, distance correlated judgment: if meet distance correlated condition, then think same target;

Distance correlated condition:

|R ₁-R ₂|≤Δtv _max+k _Rσ _R

In formula: v _maxfor target travel maximal rate, Δ t is the target measurement cycle, k _rfor distance threshold coefficient, σ _rfor distance error, R ₁for the target range value in a group pseudo-random code measuring period, R ₂for the target range value in b group pseudo-random code measuring period.

(4) to the target component of same target, get a respectively, the speed remainder of b two groups of pseudo-random codes and the fuzzy speed modulus value of integral multiple are added, and obtain each self-corresponding target possible speed value of a, b two groups of pseudo-random codes:

${\hat{V}}_{\mathrm{ai}}=i\×V_{\mathrm{mod}a}+V_1;$

${\hat{V}}_{\mathrm{bj}}=j\×V_{\mathrm{mod}b}+V_2;$

In formula: i, j=0,1 ..., N, i, j, N are natural number;

V ₁for the speed remainder measured when launching a group pseudo-random code;

V ₂for the speed remainder measured when launching b group pseudo-random code;

V _modafor the fuzzy speed modulus value that a group pseudo-random code covers;

V _modbfor the fuzzy speed modulus value that b group pseudo-random code covers;

the target possible speed value calculated for utilizing a group pseudo-random code;

the target possible speed value calculated for utilizing b group pseudo-random code;

(5) corresponding to a group pseudo-random code target possible speed value the target possible speed value corresponding with b group pseudo-random code get difference:

$\mathrm{\Δ}{d}_{\mathrm{ij}}=|{\hat{V}}_{\mathrm{ai}}-{\hat{V}}_{\mathrm{bj}}|;i,j=\mathrm{0,1},......,N;$

As difference DELTA d _ij≤ 3 σ _v, wherein σ _vfor data noise, namely meet velocity error compression context, then corresponding i, j are the fuzzy modulus value of true velocity corresponding to target velocity, and be designated as m, n, target velocity just can be expressed as:

V=m × V _moda+ V ₁or V=n × V _modb+ V ₂;

In formula: V is target velocity;

M is target true velocity Fuzzy Number Valued corresponding to a group pseudo-random code;

N is target true velocity Fuzzy Number Valued corresponding to b group pseudo-random code;

Complete target velocity to resolve.

The present invention, compared with background technology, has the following advantages:

1. adopt range segment separating object detection method, closely clutter can not disturb the detection of distant object, and distant object detectability strengthens;

2. reduce because of nearby by distance-sensitivity control method, the false-alarm that causes of sea clutter, raising radar in complex environment to the detectability of target at a slow speed.

Embodiment

The fuzzy calculation method of a kind of pseudo-random code phase modulating continuous wave radar speed, by the repetition frequency of choose reasonable modulation pseudo-code, make distance in radar range ability not fuzzy, and speed is fuzzy, specifically comprises the following steps:

(1) pseudo-random code that radar employing a, b two groups of clock frequencies are different completes an alternate wheel and sends out in wave beam residence time;

In embodiment, radar range is 25km, and radar wavelength is that 0.03m, pseudo-random code a clock frequency elects 2.5MHz as, and pseudo-random code b clock frequency elects 3MHz as, and pseudo-random code code length elects 511 as, and corresponding unambiguous distance is: 25.5km; Pseudo-random code a corresponding without fuzzy speed be 73.39m/s, pseudo-random code b corresponding be 88.06m/s without fuzzy speed; Pseudo-random code a, b alternate wheel are sent out, and it is 20ms that wheel sends out the time interval;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: distance, orientation, speed remainder and Measuring Time;

(3) judgement of same target: if the distance of target, orientation and measurement moment meet data correlation condition, be then same target;

Step (3) specifically comprises following three steps:

301, time correlation judges: if meet time correlation condition, proceed the correlated judgment of next step;

Time correlation condition is: T ₁-T ₂≤ Δ t;

Wherein: Δ t is the target measurement cycle;

T ₁for the target measurement moment in a group pseudo-random code measuring period;

T ₂for the target measurement moment in b group pseudo-random code measuring period;

302, orientation correlated judgment: if meet orientation correlated condition, proceed the correlated judgment of next step;

First calculate orientation thresholding:

Orientation thresholding: $G_A=\frac{\mathrm{\Δt}{v}_{\max }}{r_{\mathrm{pk}}}+k_A+{\mathrm{\σ}}_A;$

Wherein v _maxfor target travel maximal rate, Δ t is the target measurement cycle, σ _afor orientation angles error, k _abe respectively orientation threshold coefficient;

Orientation correlated condition is: | A ₁-A ₂|≤G _a

In formula: A ₁for the target side place value in a group pseudo-random code measuring period;

A ₂for the target side place value in b group pseudo-random code measuring period;

303, distance correlated judgment: if meet distance correlated condition, then think same target;

Distance correlated condition:

|R ₁-R ₂|≤Δtv _max+k _Rσ _R

In formula: v _maxfor target travel maximal rate, Δ t is the target measurement cycle, k _rfor distance threshold coefficient, σ _rfor distance error, R ₁for the target range value in a group pseudo-random code measuring period, R ₂for the target range value in b group pseudo-random code measuring period.

In embodiment, the echo target component of a code section launch time is R ₁=9350m, A ₁=35.6 °, V ₁=60m/s, T ₁=10.06s; The echo target component of b code section launch time is R ₂=9330m, A ₂=35.6 °, V ₂=3m/s, T ₂=10.08s; By calculating measured distance, orientation, time parameter meet data correlation relation, can think same target;

(4) to the target component of same target, get a respectively, the speed remainder of b two groups of pseudo-random codes and the fuzzy speed modulus value of integral multiple are added, and obtain each self-corresponding target possible speed value of a, b two groups of pseudo-random codes:

${\hat{V}}_{\mathrm{ai}}=i\×V_{\mathrm{mod}a}+V_1;$

${\hat{V}}_{\mathrm{bj}}=j\×V_{\mathrm{mod}b}+V_2;$

In formula: i, j=0,1 ..., N, i, j, N are natural number;

V ₁for the speed remainder measured when launching a group pseudo-random code;

V ₂for the speed remainder measured when launching b group pseudo-random code;

V _modafor the fuzzy speed modulus value that a group pseudo-random code covers;

V _modbfor the fuzzy speed modulus value that b group pseudo-random code covers;

the target possible speed value calculated for utilizing a group pseudo-random code;

the target possible speed value calculated for utilizing b group pseudo-random code;

In embodiment, calculate

${\hat{V}}_{a0}=0\×V_{\mathrm{mod}a}+V_1=0\×73.39+60=60m/s$

${\hat{V}}_{a1}=1\×V_{\mathrm{mod}a}+V_1=1\×73.39+60=133.39m/s$

${\hat{V}}_{a2}=2\×V_{\mathrm{mod}a}+V_1=2\×73.39+60=206.78m/s$

${\hat{V}}_{a3}=3\×V_{\mathrm{mod}a}+V_1=3\×73.39+60=280.17m/s$

${\hat{V}}_{a4}=4\×V_{\mathrm{mod}a}+V_1=4\×73.39+60=353.56m/s$

${\hat{V}}_{a5}=5\×V_{\mathrm{mod}a}+V_1=5\×73.39+60=426.95m/s$

${\hat{V}}_{a6}=6\×V_{\mathrm{mod}a}+V_1=6\×73.39+60=500.34m/s$

Calculate

${\hat{V}}_{b0}=0\×V_{\mathrm{mod}b}+V_2=0\×88.06+3=3m/s$

${\hat{V}}_{b1}=1\×V_{\mathrm{mod}b}+V_2=1\×88.06+3=91.06m/s$

${\hat{V}}_{b2}=2\×V_{\mathrm{mod}b}+V_2=2\×88.06+3=179.12m/s$

${\hat{V}}_{b3}=3\×V_{\mathrm{mod}b}+V_2=3\×88.06+3=267.18m/s$

${\hat{V}}_{b4}=4\×V_{\mathrm{mod}b}+V_2=4\×88.06+3=355.24m/s$

${\hat{V}}_{b5}=5\×V_{\mathrm{mod}b}+V_2=5\×88.06+3=443.3m/s$

${\hat{V}}_{b6}=6\×V_{\mathrm{mod}b}+V_2=6\×88.06+3=531.36m/s$

(5) corresponding to a group pseudo-random code target possible speed value the target possible speed value corresponding with b group pseudo-random code get difference:

$\mathrm{\Δ}{d}_{\mathrm{ij}}=|{\hat{V}}_{\mathrm{ai}}-{\hat{V}}_{\mathrm{bj}}|;i,j=\mathrm{0,1},......,N;$

As difference DELTA d _ij≤ 3 σ _v, wherein σ _vfor data noise, namely meet velocity error compression context, then corresponding i, j are the fuzzy modulus value of true velocity corresponding to target velocity, and be designated as m, n, target velocity just can be expressed as:

V=m × V _moda+ V ₁or V=n × V _modb+ V ₂;

In formula: V is target velocity;

M is target true velocity Fuzzy Number Valued corresponding to a group pseudo-random code;

N is target true velocity Fuzzy Number Valued corresponding to b group pseudo-random code;

Complete target velocity to resolve.

In embodiment, calculate Δ d _ij, be expressed as matrix form as follows:

$\mathrm{\Δd}=\left|\begin{array}{ccccccc}57& -31.06& -119.12& -207.18& -295.24& -383.3& -471.36\\ 130.39& 42.33& -45.73& -133.79& -221.85& -309.91& -397.97\\ 203.78& 115.72& 27.66& -60.4& -148.46& -236.52& -324.58\\ 277.17& 189.11& 101.05& 12.99& -75.07& -163.13& -251.19\\ 350.56& 262.5& 174.44& 86.38& -1.68& -89.74& -177.8\\ 423.95& 335.89& 247.83& 159.77& 71.71& -16.35& -104.41\\ 497.34& 409.28& 321.22& 233.16& 145.1& 57.04& -31.02\end{array}\right|$

If radar measurement errors σ _v=2m/s, then satisfy condition Δ d _ij≤ 3 σ _vonly have:

Δd _ij＝-1.68（i=4，j=4）

So have: m=4, n=4.

Target velocity can be calculated as follows:

$\begin{array}{c}V=\frac{1}{2}[(m\×V_{\mathrm{mod}a}+V_1)+(n\×V_{\mathrm{mod}b}+V_2)]\\ =\frac{1}{2}[(4\×73.39+60)+(4\×88.06+3)]=354.4m/s\end{array}$

Complete target velocity to resolve.

Claims (1)

1. the fuzzy calculation method of pseudo-random code phase modulating continuous wave radar speed, comprises the following steps:

(1) pseudo-random code that radar employing a, b two groups of clock frequencies are different completes an alternate wheel and sends out in wave beam residence time;

(2) the radar electromagnetic wave signal that reflects of receiving target respectively, and therefrom extract target component, target component comprises: distance, orientation, speed remainder and measure the moment;

(3) judgement of same target: if the distance of target, orientation and measurement moment meet data correlation condition, be then same target;

(4) to the target component of same target, get a respectively, the speed remainder of b two groups of pseudo-random codes and the fuzzy speed modulus value of integral multiple are added, and obtain each self-corresponding target possible speed value of a, b two groups of pseudo-random codes:

${\hat{V}}_{ai}=i\×V_{\mathrm{mod}a}+V_1;$

${\hat{V}}_{bj}=j\×V_{\mathrm{mod}b}+V_2;$

In formula: i, j=0,1 ..., N, i, j, N are natural number;

V ₁for the speed remainder measured when launching a group pseudo-random code;

V ₂for the speed remainder measured when launching b group pseudo-random code;

V _modafor the fuzzy speed modulus value that a group pseudo-random code covers;

V _modbfor the fuzzy speed modulus value that b group pseudo-random code covers;

the target possible speed value calculated for utilizing a group pseudo-random code;

the target possible speed value calculated for utilizing b group pseudo-random code;

(5) corresponding to a group pseudo-random code target possible speed value the target possible speed value corresponding with b group pseudo-random code get difference:

${\mathrm{\Δd}}_{ij}=|{\hat{V}}_{ai}-{\hat{V}}_{bj}|;i,j=0,1,......,N;$

As difference DELTA d _ij≤ 3 σ _v, wherein σ _vfor data noise, namely meet velocity error compression context, then corresponding i, j are true velocity Fuzzy Number Valued corresponding to target velocity, and be designated as m, n, target velocity just can be expressed as:

V=m × V _moda+ V ₁or V=n × V _modb+ V ₂;

In formula: V is target velocity;

M is target true velocity Fuzzy Number Valued corresponding to a group pseudo-random code;

N is target true velocity Fuzzy Number Valued corresponding to b group pseudo-random code;

Complete target velocity to resolve;

Wherein, step (3) specifically comprises following three steps:

301, time correlation judges: if meet time correlation condition, proceed the correlated judgment of next step;

Time correlation condition is: T ₁-T ₂≤ Δ t;

Wherein: Δ t is the target measurement cycle;

T ₁for the target measurement moment in a group pseudo-random code measuring period;

T ₂for the target measurement moment in b group pseudo-random code measuring period;

302, orientation correlated judgment: if meet orientation correlated condition, proceed the correlated judgment of next step;

First calculate orientation thresholding:

Orientation thresholding: $G_A=\frac{{\mathrm{\Δtv}}_{max}}{r_{pk}}+k_A{\mathrm{\σ}}_A;$

Wherein v _maxfor target travel maximal rate, Δ t is the target measurement cycle, σ _afor orientation angles error, k _afor orientation threshold coefficient;

Orientation correlated condition is: | A ₁-A ₂|≤G _a

In formula: A ₁for the target side place value in a group pseudo-random code measuring period;

A ₂for the target side place value in b group pseudo-random code measuring period;

303, distance correlated judgment: if meet distance correlated condition, then think same target;

Distance correlated condition:

|R ₁-R ₂|≤Δtv _max+k _Rσ _R

In formula: v _maxfor target travel maximal rate, Δ t is the target measurement cycle, k _rfor distance threshold coefficient, σ _rfor distance error, R ₁for the target range value in a group pseudo-random code measuring period, R ₂for the target range value in b group pseudo-random code measuring period.