CN106940442A - A kind of high speed missile-borne radar waveform design method - Google Patents

Abstract

Invention describes high speed missile-borne radar waveform design method, an embodiment of methods described includes：Synthetic bandwidth is limited by range resolution ratio and signal to noise ratio threshold value and its value is determined；Given frame in umber of pulse, determines number of frequency steps；Determine the lower limit of pulse recurrence frequency and the upper limit of pulse width；According to the limitation to pulse recurrence frequency span, initial value is set to pulse width；The span and value of pulse recurrence frequency are determined, if span is empty set, illustrates that the initial value of default pulse width is unreasonable, one initial value is set to pulse width again；Determine that pulse accumulation is counted；By not fuzzy distance and the final distance range for determining to be applicable of blind area distance.The technology by millimeter wave, big bandwidth, Step Frequency and weight high frequency of the embodiment, the high-speed motion for solving the decline of letter miscellaneous noise ratio, main-lobe clutter Doppler width broadening and playing between mesh causes target river across tunnel phenomenon, reaches the purpose of precision strike.

Description

A kind of high speed missile-borne radar waveform design method

Technical field

The invention belongs to Radar Technology field, it is related to the method for the signal system clutter reduction using the big bandwidth of Gao Zhongying, Rocket projectile completion Accurate Points strike is specifically ensured by the method for the big bandwidth of Gao Zhongying and terminal guidance is effectively improved The anti-clutter ability in stage.

Background technology

With the continuous development of scientific technology, the continuous improvement of national defense requirement, the development of national defence weapon is also progressively strided forward The information-based epoch.Rocket projectile has the advantages that far firing range, flat pad are simple, lethality is big, mobility good, thus into For briquettability weapon indispensable in modern war.But conventional rocket projectile only possesses face striking capabilities, it is impossible to meet The requirement of Long-range precision strike firepower, so since eighties of last century nineties, guided rocket bullet technology just rapidly develops Come and be invested in military affairs to use.Guided rocket bullet can effectively be improved while range and lethality is ensured and struck target Accuracy, in order to meet the military requirement of higher accuracy, how further to improve the accuracy of guided rocket just becomes The hot issue of people's research.

In order to further improve the accuracy of guided rocket, it is necessary first to which which factor analysis has right on guidance direction The accuracy of guided rocket produces influence, and Lou Wenzhong et al. establishes nosefuze Air Boundary Layer computation model, and he thinks winged Row Aerodynamic Heating can influence the reliability of nosefuze, therefore use the method for finite element analysis, the material different to fuse inside Analysis is modeled, current density layer functions and rocket projectile are set up by obtaining the feature of whole trajectory of rocket projectile The thermal characteristics of head fuse Air Boundary Layer, obtains fuse surface and internal Characteristics of Temperature Field, and the method effectively raises system Lead the accuracy of rocket.

In addition new idea has also been emerged on aiming means, the United Arab Emirates and Raytheon Co. of U.S. R ＆ D Cooperation half Active laser guided rocket bullet, can be shifted to an earlier date lock onto target by laser and realize high-precision strike, pass through laser guidance Not only reduce cost and improve accuracy, moreover it is possible to which reduction is incidentally injured, and greatly enhances the flexible of guidance technology Property.Strike target and determined by laser, can be the target or the airborne target of movement on ground, which solves Some limitations present in conventional guidance, can be able to apply well on unmanned plane.

Raising to guided rocket accuracy, can also be realized by being modified to guidance control system, and optimization is There is the performance of control system, Long Teng et al. analyzes the performance advantage and disadvantage of frequency step system, further provides frequency modulation stepping The Optimized model of radar signal, this signal can not only ensure emitted energy and total bandwidth compared with previous system, also The data transfer rate of system can be improved, realization efficiently and is accurately hit；Qin Yong members et al. are entered to multibarrel rocket armament systems (MLRS) Amendment is gone, has installed SINS additional and be correspondingly improved foring a kind of new guided rocket bullet, repaiied MLRS systems after just, also significantly improve the accuracy of system while with lower cost.Pass through Transfer Alignment Method, the speed of main inertial navigation and position alignment information are transmitted after error compensation with the matching scheme of " speed+attitude " To sub- inertial navigation, the initial alignment of sub- inertial navigation system is effectively completed, the accurate performance of system is improved, during the execution of system Between also very it is small.

The content of the invention

It is an object of the invention to further study the precision problem of guided rocket on the basis of above-mentioned prior art, carry Go out a kind of high-effect, high accuracy, the method for the Gao Zhongying Millimeter Wave Stepped-Frequency High Resolution Radar target seeker Waveform Design of High Data Rate.Pass through milli Metric wave, big bandwidth, Step Frequency and the technical method for weighing high frequency, solve the decline of letter miscellaneous noise ratio, main-lobe clutter Doppler width broadening And the high-speed motion played between mesh causes river across tunnel phenomenon, the purpose of enhancing precision strike is reached.

Realizing the technical scheme of the object of the invention is：Synthetic bandwidth, the value of number of frequency steps are determined first, pass through value The pulse width that is defined to of scope presets an initial value, and whether the span for judging pulse recurrence frequency is empty set, if Empty set then returns to the initial value of predetermined pulse width again, if not empty set then further determines that the value of pulse cumulative points.Its Detailed process includes as follows：

Step 1, synthesis bandwidth B is limited by range resolution ratio Δ R and signal to noise ratio detection threshold, and determined Synthetic bandwidth B value.

Step 2, a frame in number of pulses n is given, number of frequency steps Δ f is determined using the synthetic bandwidth method of frequency domain, this Lower of method need to consider relationship delta f=(B-B₁)/(n-1), meanwhile, Δ f ＜ B₁, wherein, B₁For frame in subpulse bandwidth, that is, work as Synthetic bandwidth B and frame in number of pulses n, frame in subpulse bandwidth B₁Value known to when, Δ f can be uniquely determined.

Step 3, pulse recurrence frequency PRF is determined₁Lower limit and pulse width T the upper limit, and to pulse width T Preset an initial value.

Step 4, pulse recurrence frequency PRF is determined₁Span and value, if span be empty set, illustrate in advance If pulse width T initial value it is unreasonable, return to step 3, again give pulse width T set an initial value.

Step 5, it is not empty set in response to span, determines the value of pulse accumulation points N：

P in formula_tFor emission peak power, G is antenna gain, and λ is radar signal wavelength, σ_TFor Target scatter section area, α₀For atmosphere attenuation coefficien, R_maxFor maximum operating range, k is Boltzmann constant, T₀For normal temperature, F_nFor noise coefficient, L is system loss, B_rFor receiver bandwidth, SNR_minFor signal to noise ratio detection threshold.

Step 6, according to maximum operating range, not fuzzy distance and blind area distance determine that above-mentioned waveform is applicable apart from model Enclose.

The present invention has advantages below compared with prior art：

1. big bandwidth can significantly improve the radial distance resolution ratio in terminal guidance stage, so as to reduce high-speed projectile processing Ground, sea clutter area in unit.The big bandwidth signal of Step Frequency synthesis used in the present invention can reduce system to sampling The requirement of rate and bandwidth, is effectively reduced the reality of system while the accuracy of realization and commonsense method effect same Bandwidth of operation, exploitativeness of the system in engineering is enhanced with this.

2. the present invention is using " Gao Zhongying " design on the big bandwidth base of synthesis of low cost, the design ensure that pulse Repetition period is not only no more than the corresponding target echo time delay of maximum operating range, also greater than radar main lobe irradiation area pitching Wave cover distance range, so that the interference for eliminating clutter cannot not also improve fuzzyly the scope that tests the speed, and can improve data Rate, weakening guided missile high-speed motion causes the influence of target river across tunnel.

Brief description of the drawings

Fig. 1 is the flow chart of the present invention；

Fig. 2 is to play mesh relative position schematic diagram.

Embodiment

The application is described in further detail with reference to the accompanying drawings and examples.It is understood that this place is retouched The specific embodiment stated is used only for explaining related invention, rather than the restriction to the invention.It also should be noted that, it is Be easy to illustrate only in description, accompanying drawing to about the related part of invention.

With reference to Fig. 1, the flow of one embodiment of high speed missile-borne radar waveform design method according to the application is shown 100.Described high speed missile-borne radar waveform design method, comprises the following steps：

Step 101, synthetic bandwidth is limited by range resolution ratio and signal to noise ratio threshold value, and determines synthesis The value of bandwidth.

If maximum radar range is R_max, range resolution ratio is Δ R, and the light velocity is c, then synthetic bandwidth B should expire first Foot：

Because the background clutter under the conditions of the big dive angle of high speed bullet drastically strengthens, it is maximum that signal to noise ratio detection threshold turns into restriction One principal element of operating distance, physical relationship is as follows：

B in formula_minFor the maximum operating range R_maxRequired minimum synthetic bandwidth, σ_TFor Target scatter section area, β Cape or grazing angle, θ are plunderred for radar beam_0.5For 3dB beam angles, SCR_minFor signal to noise ratio detection threshold, γ₀For clutter background Reflectivity, tan β are β tangent value.

Signal to noise ratio detection threshold determines the maximum operating range R as can be seen from the above equation_maxWhen also to the anamorphic zone Wide B has done following limitation, i.e.,：

Step 102, frame in number of pulses is given, number of frequency steps is determined using the synthetic bandwidth method of frequency domain.

A frame in number of pulses n is given, is determined using the synthetic bandwidth method of frequency domain under number of frequency steps Δ f, the method Relationship delta f=(B-B only need to be considered₁)/(n-1), while Δ f ＜ B₁, wherein, B₁For frame in subpulse bandwidth, that is, work as anamorphic zone Wide B, frame in umber of pulse n, frame in subpulse bandwidth B₁Value known to when, Δ f can be uniquely determined.

Step 103, the lower limit of pulse recurrence frequency and the upper limit of pulse width are determined, and it is default to pulse width One initial value.

Determine pulse recurrence frequency PRF₁Lower limit and pulse width T the upper limit, and to pulse width T default one Individual initial value.Solve main-lobe clutter Doppler width Δ f_d, main-lobe clutter Doppler width Δ f_dTo pulse recurrence frequency PRF₁'s It is determined that also having certain limitations, Fig. 2 is to play the relative position relation between mesh, i.e. relative position relation between guided missile and target, Wherein, 201 guided missile, the region where the region representation target of 202 ellipse delineations are represented.If v_mFor missile flight speed, α For radar main beam azimuth, β is radar main beam dive angle, and λ is radar signal wavelength, then how general radar main beam center is Strangle frequency f_dFor：

According to above-mentioned formula and combination 3dB beam angles θ_0.5, obtain the main-lobe clutter Doppler width Δ f_dFor：

Determine pulse recurrence frequency PRF₁Lower limit and pulse width T the upper limit：Due to pulse recurrence frequency PRF₁And frame Repetition rate PRF₂Meet relation PRF₁=nPRF₂.Do not obscured to meet main-lobe clutter, it is desirable to frame repetition frequency PRF₂Should More than main-lobe clutter Doppler width Δ f_d, therefore have：

PRF₁＞ n Δs f_d

Simultaneously in view of dutycycle η_maxRequirement, i.e. PRF₁T ＜ η_max, so：

Or

Step 104, the span and value of pulse recurrence frequency are determined, if pulse recurrence frequency span is Empty set, illustrates that default pulse width T initial value is unreasonable, return to step 103, is set again to pulse width T at the beginning of one Value.

Solve not limitation of the fuzzy distance to pulse recurrence frequency：If radar it is interested apart from siding-to-siding block length be R_actIts In, R_actIt can be determined by beam coverage, the corresponding blind area distances of pulse width T are cT/2.In order to avoid apart from upper folding Often radar not fuzzy distance R is required in folded problem, engineer applied_uMore than it is interested apart from siding-to-siding block length and blind area apart from it With that is,：

R_u＞ R_act+cT/2

Not fuzzy distance R is required simultaneously_uWith pulse recurrence frequency PRF₁Meet following restriction relation：

Again by PRF₁＞ n Δs f_dWithDetermine pulse recurrence frequency PRF₁Span and value.

Step 105, it is not empty set in response to span, determines that pulse accumulation is counted.

If radar 3dB beam angles are θ_0.5, the pulse repetition period is T_r, radar antenna sweep speed is ω_s, it is contemplated that The limitation of wave beam residence time, the echo impulse number of target should meet following relation in the time for point target that antenna is inswept：

Simultaneously in view of data transfer rate T_sLimitation, the total integration time for point target that antenna is inswept should be less than 1/T_s, i.e. N T_r＜ 1/T_s, therefore can obtain：

N ＜ 1/T_rT_s

Velocity resolution σ_vFollowing relation is met with pulse accumulation points N：

σ_v=λ PRF₁/2N

Therefore as velocity resolution σ_vLess than a certain value σ_v0, can obtain：

N ＞ λ PRF₁/2σ_v0

In view of the constraint of signal to noise ratio, frame accumulation number N can be obtained_FMeet：

By relational expression N=nN_FIt can obtain：

P in formula_tFor emission peak power, G is antenna gain, and λ is radar signal wavelength, σ_TFor Target scatter section area, α₀For atmosphere attenuation coefficien, R_maxFor maximum operating range, k is Boltzmann constant, T₀For normal temperature, F_nFor noise coefficient, L is system loss, B_rFor receiver bandwidth, SNR_minFor signal to noise ratio detection threshold, N_FNumber is accumulated for frame.

Step 106, the applicable distance range of waveform is determined according to maximum operating range, fuzzy distance and blind area distance.

According to above-mentioned maximum operating range R_max, above-mentioned not fuzzy distance R_uWith above-mentioned blind area ripple is finally determined apart from cT/2 Shape applicable distance range R, i.e. R_min＜ R ＜ R_max, wherein R_min=R_max-R_u+ cT/2, R_minRepresent the above-mentioned waveform scope of application R lower limit.

Advantages of the present invention can be further illustrated by emulating data experiment.

1. simulation parameter

In this experiment, the service band of certain high speed missile-borne radar target seeker is Ka wave bands (λ=8.6mm), and its technology refers to Mark requires as follows：Maximum operating range R_maxFor 30km, azimuth angle alpha is 23 °, and dive angle β is 60 °, missile flight speed v_mFor 1200m/s, dutycycle η_maxLess than 30%, range resolution ratio Δ R is 1m, velocity resolution 1m/s, 3dB beam angle θ_0.5For 2.9 °, target signal to noise ratio detection threshold SCR_minFor 13dB, data transfer rate T_sFor 50Hz, Target scatter section area σ_TMore than 1000m²。

2. emulate data processed result and analysis

The parameter value of 2.1 influence synthetic bandwidths is shown in Table 1 (γ₀Value by taking 4 grades of sea conditions as an example).

Table 1 influences the parameter value of synthetic bandwidth

Parameter

Rmax

ΔR

β

θ0.5

SCRmin

γ0

σT

Value

30km

1m

60°

2.9°

13dB

-11dB

1000m2

B >=150MHz can be obtained by range resolution ratio Δ R limitation, B >=625MHz can be obtained by the limitation of signal to noise ratio.To sum up, Take synthetic bandwidth B=750MHz.

Number of frequency steps Δ f selection

Take frame in umber of pulse n=8, frame in subpulse bandwidth B₁=120MHz, by relational expression Δ f=(B-B₁)/(n-1) can Obtain number of frequency steps Δ f=90MHz.

Pulse width T selection

Due to missile flight speed v_m=1200m/s, calculates a width of Δ f of main-lobe clutter doppler spectral_d=2.76kHz；By PRF₁＞ n Δs f_dPulse recurrence frequency PRF can be obtained₁＞ 22.08kHz；ByThe μ of pulse width T ＜ 13.6 can be obtained S, therefore default T=10 μ s.

Pulse recurrence frequency PRF₁Selection

As T=10 μ s, PRF can be obtained₁＞ 42kHz (R_act=2km), PRF₁＞ 22.08kHz, PRF₁＜ 30kHz；It is comprehensive On, PRF₁Obtained in the range of 22.08~30kHz, finally determine PRF₁=25kHz.

The selection of pulse accumulation points N

Due to PRF₁=25kHz, therefore pulse repetition period T_r=40 μ s, the parameter value of influence pulse accumulation points is shown in Table 2.

The parameter value of the influence pulse accumulation points of table 2

Parameter	Value	Parameter	Value
				Tr	40μs	α0	0.16dB/km
ηmax	30%	k	1.38×10-23
				Rmax	30km	T0	290K
Pt	40W	Fn	5dB
				G	35dB	L	12dB
λ	8.6mm	Br	36MHz
				σT	1000m2	B	750MHz
NF	16	(SNR)min	13dB
				θ0.5	2.9°	ωs	60°/s
Ts	50Hz	σv0	1m/s

ByN≤1208 can be obtained；By N<1/T_rT_sN can be obtained<500；By N>λPRF₁/2σ_v0N can be obtained>108；ByWithN >=80 (now N can be obtained_F≥ , therefore 108 10)<N<500, it is contemplated that integration time, unsuitable long and FFT computings were convenient, final to determine accumulation number N= 128。

Work as PRF₁=25kHz, T=10 μ s, c=3 × 10⁸When, byNot fuzzy distance R can be obtained_uFor 6km, Blind area is 1.5km apart from cT/2, because maximum operating range is 30km, 30-6+1.5=25.5, so above-mentioned parameter can be met 25.5~30km Waveform Design.Waveform Design in other operating distances can one by one be completed according to above-mentioned steps.

2.2 experiment conclusions：

Describe the process of Gao Zhongying Millimeter Wave Stepped-Frequency High Resolution Radar target seeker Waveform Design in the present invention in detail and required Theories integration, and incorporation engineering application completes seeker contrived experiment, test result indicate that this method can be solved effectively The problem of rocket projectile technology existing at present radar seeker Waveform Design, and improve the accuracy of guided rocket.

Claims (5)

1. high speed missile-borne radar waveform design method, comprises the following steps：

Step 1 is limited synthesis bandwidth B by range resolution ratio Δ R and signal to noise ratio detection threshold, and determines the conjunction Into the value of bandwidth B；

Step 2 gives a frame in number of pulses n, is determined using the synthetic bandwidth method of frequency domain under number of frequency steps Δ f, the method Relationship delta f=(B-B only need to be considered₁)/(n-1), while Δ f ＜ B₁, wherein, B₁For frame in subpulse bandwidth, i.e., when the synthesis Bandwidth B, the frame in number of pulses n, the frame in subpulse bandwidth B₁Value known to when, Δ f can be uniquely determined；

Step 3 determines pulse recurrence frequency PRF₁Lower limit and pulse width T the upper limit, and to the pulse width T preset One initial value；

Step 4 determines the pulse recurrence frequency PRF₁Span and value, if the span be empty set, explanation Default pulse width T initial value is unreasonable, return to step 3, sets an initial value to the pulse width T again；

Step 5 is not empty set in response to the span, determines the value of pulse accumulation points N：

$N\&GreaterEqual;n\&CenterDot;\frac{R_{max}^4{\left(4\mathrm{\&pi;}\right)}^3{\mathrm{kT}}_0{B}_r{F}_{n}L{\left(SNR\right)}_{\min }}{P_t{G}^2{\mathrm{\&lambda;}}^2{\mathrm{\&sigma;}}_T\&times;{10}^{-0.2{\mathrm{\&alpha;}}_0{R}_{\max }}BT}$

P in formula_tFor emission peak power, G is antenna gain, and λ is radar signal wavelength, σ_TFor Target scatter section area, α₀To be big Gas attenuation coefficient, R_maxFor maximum operating range, k is Boltzmann constant, T₀For normal temperature, F_nFor noise coefficient, L is system Loss, B_rFor receiver bandwidth, (SNR)_minFor signal to noise ratio detection threshold；

Step 6 is according to the maximum operating range, fuzzy distance and blind area distance do not determine the applicable distance range of waveform.

2. high speed missile-borne radar waveform design method according to claim 1, wherein passes through Range resolution described in step 1 Rate Δ R and signal to noise ratio detection threshold are limited synthesis bandwidth B, and determine the value of the synthetic bandwidth B, including as follows Step：

2a) determine limitations of the range resolution ratio Δ R to the synthetic bandwidth B：C is the light velocity, then the synthetic bandwidth B is first It should meet：

$B\&GreaterEqual;\frac{c}{2\mathrm{\&Delta;}R}$

2b) determine limitation of the signal to noise ratio detection threshold to the synthetic bandwidth B：Due to the background under the conditions of the big dive angle of high speed bullet Clutter drastically strengthens, and the signal to noise ratio detection threshold turns into restriction maximum operating range R_maxA principal element, physical relationship It is as follows：

$R_{max}=\frac{2B_{\min }{\mathrm{\&sigma;}}_T}{{\mathrm{SCR}}_{\min }{\mathrm{\&theta;}}_{0.5}{\mathrm{c\&gamma;}}_{0}tan\mathrm{\&beta;}}$

B in formula_minFor the maximum operating range R_maxRequired minimum synthetic bandwidth, σ_TFor Target scatter section area, β is radar Wave beam plunders cape or grazing angle, θ_0.5For 3dB beam angles, SCR_minFor signal to noise ratio detection threshold, γ₀Reflected for clutter background Rate, tan β are β tangent value；

Signal to noise ratio detection threshold determines the maximum operating range R as can be seen from the above equation_maxWhen also the synthetic bandwidth B is done Following limitation, i.e.,：

$B\&GreaterEqual;B_{\min }=\frac{R_{\max }{\mathrm{SCR}}_{\min }{\mathrm{\&theta;}}_{0.5}{\mathrm{c\&gamma;}}_0\tan \mathrm{\&beta;}}{2{\mathrm{\&sigma;}}_T}$

3. high speed missile-borne radar waveform design method according to claim 1, the determination pulse wherein described in step 3 is repeated Frequency PRF₁Lower limit and pulse width T the upper limit, and to the pulse width T preset an initial value method, including Following steps：

3a) solve main-lobe clutter Doppler width Δ f_d, the main-lobe clutter Doppler width Δ f_dTo the pulse recurrence frequency PRF₁Determination also have certain limitations, if v_mFor missile flight speed, α is radar main beam azimuth, and β bows for radar main beam The angle of attack, λ is radar signal wavelength, then radar main beam center Doppler frequency f_dFor：

$f_d=\frac{2v_{m}cos\mathrm{\&beta;}cos\mathrm{\&alpha;}}{\mathrm{\&lambda;}}$

According to above-mentioned formula and combination 3dB beam angles θ_0.5, obtain the main-lobe clutter Doppler width Δ f_dFor：

$\begin{array}{c}{\mathrm{\&Delta;f}}_d=\frac{2v_m\cos \mathrm{\&beta;}\&lsqb;\cos \left(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_{0.5}/2\right)-\cos \left(\mathrm{\&alpha;}+{\mathrm{\&theta;}}_{0.5}/2\right)\&rsqb;}{\mathrm{\&lambda;}}\\ =\frac{4v_m\cos \mathrm{\&beta;}\sin \mathrm{\&alpha;}\sin \left({\mathrm{\&theta;}}_{0.5}/2\right)}{\mathrm{\&lambda;}}\\ \&ap;\frac{2v_m{\mathrm{\&theta;}}_{0.5}\cos \mathrm{\&beta;}\sin \mathrm{\&alpha;}}{\mathrm{\&lambda;}}\end{array}$

3b) determine pulse recurrence frequency PRF₁Lower limit and pulse width T the upper limit：Due to pulse recurrence frequency PRF₁And frame Repetition rate PRF₂Meet relation PRF₁=nPRF₂, do not obscured to meet main-lobe clutter, it is desirable to the frame repetition frequency PRF₂It should be greater than the main-lobe clutter Doppler width Δ f_d, therefore have：

PRF₁＞ n Δs f_d

Simultaneously in view of dutycycle η_maxRequirement, i.e. PRF₁T ＜ η_max, so：

Or

4. high speed missile-borne radar waveform design method according to claim 1, wherein pulse described in the determination described in step 4 Repetition rate PRF₁Span and value, comprise the following steps：

4a) solve not fuzzy distance R_uTo the pulse recurrence frequency PRF₁Limitation：If radar is interested apart from siding-to-siding block length For R_act, the corresponding blind area distance of the pulse width T is cT/2, in order to avoid in upper folding problem, engineer applied often It is required that radar not fuzzy distance R_uIt is interested apart from siding-to-siding block length R more than described_actWith the blind area apart from cT/2 sums, i.e.,：

R_u＞ R_act+cT/2

Not fuzzy distance R require simultaneously described in_uWith the pulse recurrence frequency PRF₁Meet following restriction relation：

${\mathrm{PRF}}_1<\frac{c}{2R_u}$

4b) again by PRF₁＞ n Δs f_dWithDetermine the pulse recurrence frequency PRF₁Span and value.

5. high speed missile-borne radar waveform design method according to claim 1, wherein described in step 5 in response to described Span is not empty set, determines the value of pulse accumulation points N, comprises the following steps：

If radar 3dB beam angles are θ_0.5, the pulse repetition period is T_r, radar antenna sweep speed is ω_s, it is contemplated that wave beam is stayed The limitation of time is stayed, the echo impulse number N of target should meet following relation in the time for point target that antenna is inswept：

$N\&le;\frac{{\mathrm{\&theta;}}_{0.5}}{{\mathrm{\&omega;}}_s\&times;T_r}$

Simultaneously in view of data transfer rate T_sLimitation, the total integration time for point target that antenna is inswept should be less than 1/T_s, i.e. NT_r＜ 1/T_s, therefore can obtain：

N ＜ 1/T_rT_s

Velocity resolution σ_vFollowing relation is met with pulse accumulation points N：

σ_v=λ PRF₁/2N

Therefore as the velocity resolution σ_vLess than a certain value σ_v0, can obtain：

N ＞ λ PRF₁/2σ_v0

In view of the constraint of signal to noise ratio, frame accumulation number N can be obtained_FMeet：

$N_F\&GreaterEqual;\frac{R_{max}^4{\left(4\mathrm{\&pi;}\right)}^3{\mathrm{kT}}_0{B}_r{F}_{n}L{\left(SNR\right)}_{\min }}{P_t{G}^2{\mathrm{\&lambda;}}^2{\mathrm{\&sigma;}}_T\&times;{10}^{-0.2{\mathrm{\&alpha;}}_0{R}_{max}}BT}$

P in formula_tFor emission peak power, G is antenna gain, and λ is radar signal wavelength, σ_TFor Target scatter section area, α₀To be big Gas attenuation coefficient, R_maxFor maximum operating range, k is Boltzmann constant, T₀For normal temperature, F_nFor noise coefficient, L is system Loss, B_rFor receiver bandwidth, (SNR)_minFor signal to noise ratio detection threshold；

By relational expression N=nN_FIt can obtain：

$N\&GreaterEqual;n\&CenterDot;\frac{R_{max}^4{\left(4\mathrm{\&pi;}\right)}^3{\mathrm{kT}}_0{B}_r{F}_{n}L{\left(SNR\right)}_{\min }}{P_t{G}^2{\mathrm{\&lambda;}}^2{\mathrm{\&sigma;}}_T\&times;{10}^{-0.2{\mathrm{\&alpha;}}_0{R}_{\max }}BT}$