CN204515123U - A kind of echo wave signal acquisition device of millimetre-wave radar - Google Patents

Abstract

The utility model relates to radar signal field, it is a kind of echo wave signal acquisition device of millimetre-wave radar, its object is to provide a kind of effectively to improve system signal noise ratio and the echo wave signal acquisition device of a kind of millimetre-wave radar of system complexity can be reduced, a kind of echo wave signal acquisition device of millimetre-wave radar, comprise the frequency mixer and wave filter that are linked in sequence, also comprise signal acquisition module, described signal acquisition module comprises the AD conversion unit, clock generator and the control module that are connected to each other.The utility model has the signal acquisition module of control module and clock generator by arranging, greatly improve system signal noise ratio SNR; The utility model adopts high-frequency clock generator and high-speed AD converter to carry out ultra high speed signal sampling, greatly improves the stability of sampling, prevents frequency alias, realize the reduction of the full detail of echoed signal; The utility model structure is simple, improves stability and the anti-interference of system.

Description

A kind of echo wave signal acquisition device of millimetre-wave radar

Technical field

The utility model relates to radar signal field, particularly a kind of echo wave signal acquisition device of millimetre-wave radar.

Background technology

Digital signal processing has obtained in fields such as radar, Industry Control, communications relative to the superiority of analog intermediate frequency process and has verified widely, and simulating signal is converted into bridge and the prerequisite that digital signal (signal sampling technology) is digital signal processing.

The field widespread uses such as the advantages such as millimetre-wave radar is high with its range resolution, rate accuracy is high, strong interference immunity are accurately located at radar, target identification, target trajectory prediction.Because millimetre-wave radar system signal bandwidth is increasing, the requirement of radar signal collection is also increased, more and more higher especially to the requirement of analog-to-digital conversion device and Sampling techniques.The requirement of millimetre-wave radar to signal bandwidth, dynamic range, real-time property is higher, and this is obviously that low speed signal sampling and common high speed signal Sampling techniques cannot realize.

For the problems referred to above, prior art generally adopts two-stage mixing and one-level frequency spectrum shift to solve;

Particularly the first order is by radio-frequency echo wave frequency spectrum shift to higher the first intermediate frequency of frequency in two-stage mixing, and the first intermediate frequency is moved to the second lower intermediate frequency of frequency by second level mixing again.But its complex structure, debugging difficulty is large, and not easy of integration, cost is high; This technology is made up of mimic channel mostly, and structure is comparatively complicated, poor stability, poor anti jamming capability; And this technology adopts repeatedly mixing, noise is comparatively large, and signal to noise ratio (S/N ratio) reduces; Millimetre-wave radar echoed signal is particularly first carried out mixing and filtering by one-level frequency spectrum shift, by radio-frequency echo wave frequency spectrum shift to the higher intermediate frequency of frequency, then enters sampling by common high speed analog-digital conversion converter to the intermediate-freuqncy signal after frequency-selective filtering.Because IF signal frequency is higher, the conversion sample frequency of modulus switching device does not reach more than the twice of IF signal frequency, but the sampling rate of its bandpass sampling is low, and accumulate number in storehouse less, signal to noise ratio (S/N ratio) is poor; Bandpass sampling easily causes frequency alias, requires higher, not easily realize the filtering transitional zone of signal processor.Problem.

Assistant officer is to appear a kind ofly effectively can improve system signal noise ratio and can reduce the echo wave signal acquisition device of a kind of millimetre-wave radar of system complexity.

Utility model content

The echo wave signal acquisition device of a kind of millimetre-wave radar that the utility model provides, its object is to provide a kind of signal pickup assembly that can effectively solve the problem.

The technical solution of the utility model is achieved in that a kind of echo wave signal acquisition device of millimetre-wave radar, comprise the frequency mixer and wave filter that are linked in sequence, also comprise signal acquisition module, described signal acquisition module comprises the AD conversion unit, clock generator and the control module that are connected to each other.

Further, described control module is FPGA device.

Further, described FPGA device comprises for configuring and control the clock generator control part of clock generator and the AD conversion unit control part for gathering, accepting and process intermediate-freuqncy signal.

Optimally, described clock generator is AD9516-3 clock chip.

Optimally, described AD conversion unit is AD9467-250 high-speed AD converter.

Optimally, described wave filter is loop filter.

The echo wave signal acquisition device of a kind of millimetre-wave radar that the utility model provides, by arranging the signal acquisition module with control module and clock generator, improves system signal noise ratio SNR greatly; The utility model adopts high-frequency clock generator and high-speed AD converter to carry out ultra high speed signal sampling, greatly improves the stability of sampling, prevents frequency alias, realize the reduction of the full detail of echoed signal; The utility model structure is simple, improves stability and the anti-interference of system.

Accompanying drawing explanation

In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only embodiments more of the present utility model, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1: module diagram of the present utility model;

Fig. 2: AD9467 modularization design figure;

Fig. 3: AD9467 output timing;

Fig. 4: AD9516-3 clock chip.

In figure: 100, signal acquisition module; 110, FPGA device; 111, clock generator control part; 112, AD conversion unit control part; 120, AD conversion unit; 130, clock generator; 200, frequency mixer; 300 wave filters.

Embodiment

Below in conjunction with the accompanying drawing in the utility model embodiment, be clearly and completely described the technical scheme in the utility model embodiment, obviously, described embodiment is only the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.

Shown in module diagram as of the present utility model in Fig. 1, a kind of echo wave signal acquisition device of millimetre-wave radar, comprise the frequency mixer 200 and wave filter 300 that are linked in sequence, also comprise signal acquisition module 100, described signal acquisition module 100 comprises the AD conversion unit 120, clock generator 130 and the control module that are connected to each other.

Further, described control module is FPGA device 110.Further, described FPGA device 110 comprises for configuring and control the clock generator control part 111 of clock generator and the AD conversion unit control part 112 for gathering, accepting and process intermediate-freuqncy signal.

Optimally, described clock generator 130 is AD9516-3 clock chip.Optimally, described AD conversion unit 120 is AD9467-250 high-speed AD converter.Optimally, described wave filter is loop filter.

The utility model adopts the over-sampling mode of ultra-high speed sampling rate to radar echo signal, and sampling process follows sampling thheorem, and sampling thheorem explains the relation between sample frequency and signal spectrum, is the basic foundation of continuous signal discretize.If have a frequency to be the signal of F, when sampling time interval Δ t >=1/2F is lack sampling; When sampling time interval Δ t≤1/2F is over-sampling.Over-sampling is only had to recover original signal completely according to each sampled value and can not frequency alias be caused.

As shown in Fig. 2: AD9467 modularization design figure, AD conversion unit 120 of the present utility model adopts high precision, high sampling rate converter AD9467-250, its sampling precision 16bits, maximum sampling rate 250MSPS, Spurious Free Dynamic Range SFDR maximal value is 100dBFS, input bandwidth can reach 300MHz, and maximum unsaturated level+12dBm, in practical application, signal to noise ratio (S/N ratio) can reach more than 75dB.AD9467-250 configuration is simple, configurable mode of operation, low level in a front or high position at front, output driving current.As shown in Fig. 3 AD9467 output timing, known AD9467 data export and adopt the differential pair way of output, and antijamming capability is strong, and adopts DCO rising edge and negative edge to latch the high-low-position of output 16 bit data respectively.

As known in Fig. 4 AD9516-3 clock chip, AD9516 clock chip exports the frequency division register related to be had: produce R, A and B-register, clock output frequency division register, the often pair of output port frequency division register of stablizing VCO for PLL.These 3 registers of R, A and B of PLL need cooperatively interact setting, and VCO just can be operated in required frequency range, otherwise will cause latching phase-locked module.Its relation is shown in following formula

$\begin{array}{cc}{f}_{\mathrm{vco}}=f_{\mathrm{ref}}\×\frac{N}{R},& N=P\×B+A(B\≥A)\end{array}$

Wherein P is scale factor optional 2,4,6,8,16 or 32.Clock output frequency divider can be set to the arbitrary integer in 2 to 6, and each frequency divider of output port can select arbitrary integer in 1 to 32 as frequency division parameter.

The echo wave signal acquisition device of a kind of millimetre-wave radar that the utility model provides, by arranging the signal acquisition module 110 with control module and clock generator, improves system signal noise ratio SNR greatly; The utility model adopts high-frequency clock generator 130 and high-speed AD converter to carry out ultra high speed signal sampling, greatly improves the stability of sampling, prevents frequency alias, realize the reduction of the full detail of echoed signal; The utility model structure is simple, improves stability and the anti-interference of system.

Certainly; when not deviating from the utility model spirit and essence thereof; those of ordinary skill in the art should make various corresponding change and distortion according to the utility model, but these change accordingly and are out of shape the protection domain that all should belong to the claim appended by the utility model.

Claims (6)

1. the echo wave signal acquisition device of a millimetre-wave radar, comprise the frequency mixer and wave filter that are linked in sequence, it is characterized in that: also comprise signal acquisition module, described signal acquisition module comprises the AD conversion unit, clock generator and the control module that are connected to each other.

2. the echo wave signal acquisition device of a kind of millimetre-wave radar according to claim 1, is characterized in that: described control module is FPGA device.

3. the echo wave signal acquisition device of a kind of millimetre-wave radar according to claim 2, is characterized in that: described FPGA device comprises for configuring and control the clock generator control part of clock generator and the AD conversion unit control part for gathering, accepting and process intermediate-freuqncy signal.

4. according to the echo wave signal acquisition device of a kind of millimetre-wave radar in claim 1-3 described in any one, it is characterized in that: described clock generator is AD9516-3 clock chip.

5. according to the echo wave signal acquisition device of a kind of millimetre-wave radar in claim 1-3 described in any one, it is characterized in that: described AD conversion unit is AD9467-250 high-speed AD converter.

6. according to the echo wave signal acquisition device of a kind of millimetre-wave radar in claim 1-3 described in any one, it is characterized in that: described wave filter is loop filter.