CN108548958A - A kind of rapid frequency-sweeping system and method for spectrum detector - Google Patents
A kind of rapid frequency-sweeping system and method for spectrum detector Download PDFInfo
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- CN108548958A CN108548958A CN201810275659.6A CN201810275659A CN108548958A CN 108548958 A CN108548958 A CN 108548958A CN 201810275659 A CN201810275659 A CN 201810275659A CN 108548958 A CN108548958 A CN 108548958A
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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- G01R23/16—Spectrum analysis; Fourier analysis
- G01R23/165—Spectrum analysis; Fourier analysis using filters
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Abstract
The present invention discloses a kind of rapid frequency-sweeping system and method for spectrum detector, the analog signal of radio-frequency module output is mixed after AD is sampled with DDS, the frequency of the intermediate settings of DDS all the way is f (identical as the centre frequency of radio-frequency module output), and the frequency that other DDS are respectively set is f ± (n 1) * f1/ 2, that is, it is symmetrical arranged, f1 sweeps width for each small bucket's；By the extraction frequency reducing of cic filter and the complete paired data of HB filters, the forming of waveform is completed by RBW filters；It directly invokes cordic modules and finds out range value and phase value, signal carries out small bucket access again after VBW modules are smooth；Data after bucket access small to the roads n are merged into all the way through too small bucket data combiners blocks according to the principle of frequency from big to small, are then carried out various detections under the control of big bucket signals, are finally given display module.
Description
Technical field
The present invention relates to the rapid frequency-sweeping system of spectrum detector and methods more particularly to a kind of spectrum monitoring analyzer to supervise
The place for surveying the frequency spectrum of quick variable signal belongs to communication test field.
Background technology
It (is typically all that FPGA is realized, it is assumed that penetrate that the frequency sweep structure of more common spectrum detector is following both at home and abroad at present
Frequency module output is 10.7M intermediate-freuqncy signals)：
If the rate of AD samplings is 100M, after extracting and reducing, the sampling rate under the RBW gears of part becomes：
Table one
If screen will show 501 points (total number of i.e. big bucket), in order to go out a display point, i.e., one big
Bucket points, it is assumed that need 3 small bucket to go out one big bucket points, that is, control number (the i.e. small bucket of radio-frequency module
Total number) be：501*3=1503, it is assumed that RBW filters are 21 grades, i.e. tap number is 21, often go out a small bucket,
It needs to refresh 21 data, then so the calculating of theoretic sweep time is as follows：
Table two
The calculating of above-mentioned time, and the signal actually caught in FPGA is almost the same.
So in RBW=1k, the renewal time of screen previous frame needs 6S or so, this leverages observation and quickly becomes
The frequency spectrum of the signal of change.
Invention content
The structure of traditional intermediate frequency frequency sweep is all the way, as shown in Figure 1.It is wide similarly sweeping in order to improve sweep velocity
In the case of, it, can be by increasing substantially the sweep interval of radio frequency, to reduce control in the case where not changing radio-frequency module
The number of radio frequency reduces the refreshing frequency for the data for being defeated by RBW filters, however, to ensure that accuracy, the reality of intermediate frequency
Border sweep interval can not be reduced, if the control number to radio frequency is kept to original 1/n (n>1, and n is odd number), then intermediate frequency
Just need and symmetrical structure parallel using the roads n, the i.e. center of the set frequency of intermediate DDS all the way and radio-frequency module output
Frequency is identical, and the setting of the frequency of other DDS is then symmetrical arranged with the wide interval of sweeping of each small bucket successively, but in
The parallel frequency sweep way in the roads frequency n is limited by the bandwidth of radio-frequency filter, i.e., wide n times of sweeping of small bucket is necessarily less than radio frequency filter
The three dB bandwidth of wave device.
In order to solve problem above, present invention employs following technical solutions：
The present invention provides a kind of rapid frequency-sweeping systems of spectrum detector, which is characterized in that including the following contents：Including
A/D module, n Direct Digital Synthesizer DDS combinations, cic filter, HB filters, RBW filters, cordic moulds
Block, VBW modules, small bucket, small bucket data combiners blocks, big bucke, display module, wherein n is more than 1 odd number；
Every group of DDS is combined as, and the COS signal ends of a DDS connect I input terminal of frequency mixer, the SIN signal ends connection of DDS
II input terminal of frequency mixer；The input terminal of frequency mixer I and frequency mixer II is also connected with A/D module output end；Frequency mixer I and frequency mixer
II output end is separately connected a cic filter, the input terminal of the output end connection HB filters of each cic filter, HB
The input terminal of the output end connection RBW filters of filter, the output end of RBW filters connect cordic modules, cordic moulds
Block is also connected with the input terminal of the roads n VBW modules, and the output end of a VBW module connects the input terminal of a small bucket, the roads n
The input terminal of small bucket connects small bucket data combiners blocks, and small bucket is also connected with the input terminal of big bucke, greatly
The output end of bucke connects display module；
The analog signal of radio-frequency module output is mixed after AD is sampled with DDS, and the frequency of the intermediate settings of DDS all the way is f,
The frequency that its DDS is respectively set is f ± (n-1) * f1/ 2, that is, it is symmetrical arranged, f1 sweeps width for each small bucket's；
According to the resource requirement of the formed filter RBW of rear end, need to carry out extraction frequency reducing to data, by cic filter
It is completed with HB filters, since the data input frequency of cic filter is identical with the sampling clock of AD, so cannot answer the time-division
With, and the frequency of the input data of HB filters has substantially reduced, in order to save resource, HB filters are using time division multiplexing mould
Formula；
RBW filters are designed according to three three dB bandwidth, bandwidth selectivity and stopband attenuation indexs, complete waveform
Forming, the frequency of the input data of same RBW filters has substantially reduced, in order to save resource, when RBW filters also use
Divide multiplexer mode；
It directly invokes cordic modules and finds out range value and phase value, when being far below the sampling of AD due to its input data
Clock, in order to save resource, cordic modules use time division multiplexing；
VBW modules are smoothed to display result；Signal after VBW modules are smooth is taken in small bucket
Number；
Original of the data through too small bucket data combiners blocks according to frequency from big to small after bucket access small to the roads n
It is then merged into all the way, then carries out various detections under the control of big bucket signals, it is aobvious finally to give display module progress data
Show.
The present invention also provides a kind of rapid frequency-sweeping methods of spectrum detector, which is characterized in that including the following contents：
The analog signal of radio-frequency module output is mixed after AD is sampled with DDS, and the frequency of the intermediate settings of DDS all the way is f,
The frequency that its DDS is respectively set is f ± (n-1) * f1/ 2, that is, it is symmetrical arranged, f1 sweeps width for each small bucket's；
According to the resource requirement of the formed filter RBW of rear end, need to carry out extraction frequency reducing to data, by cic filter
It is completed with HB filters, since the data input frequency of cic filter is identical with the sampling clock of AD, so cannot answer the time-division
With, and the frequency of the input data of HB filters has substantially reduced, in order to save resource, HB filters are using time division multiplexing mould
Formula；
RBW filters are designed according to three three dB bandwidth, bandwidth selectivity and stopband attenuation indexs, complete waveform
Forming, the frequency of the input data of same RBW filters has substantially reduced, in order to save resource, when RBW filters also use
Divide multiplexer mode；
It directly invokes cordic modules and finds out range value and phase value, when being far below the sampling of AD due to its input data
Clock, in order to save resource, cordic modules use time division multiplexing；
VBW modules are smoothed to display result；Signal after VBW modules are smooth is taken in small bucket
Number；
Original of the data through too small bucket data combiners blocks according to frequency from big to small after bucket access small to the roads n
It is then merged into all the way, then carries out various detections under the control of big bucket signals, it is aobvious finally to give display module progress data
Show.
The width of sweeping of each of described small bucket is f1=M/ (K*L)；K is that display is counted, that is, contains K big bucket,
Each big bucket contains L small bucket, and wide M is swept in upper application software setting.
Control and single pass relevant control due to the big bucket and small bucket of intermediate frequency multidiameter delay have occurred and that
Prodigious variation, upper layer software (applications) often control a radiofrequency signal, and traditional intermediate frequency scanning system can only go out a small bucket
Data, and the parallel system in the roads intermediate frequency n can go out n small bucket data simultaneously, and the small bucket data in the roads n are given successively
Detection module is labeled as point of penetration with big bucket, carries out peak detection, normality detection etc. then in detection module, for
Subsequent storage and display are used.
Advantageous effect：
Since the digital filter of FPGA can easily be accomplished to be time-multiplexed very much, so the FPGA of intermediate frequency multidiameter delay disappears
The resource of consumption is not single pass simple n times of expansion, it is thus only necessary to it is additional to increase DDS and CIC resources, in utilization
The frequency sweep time of the frequency sweep structure of frequency multidiameter delay is all n times of diminution.
Description of the drawings
Fig. 1 is traditional single channel intermediate frequency scanning system block diagram.
Fig. 2 is a kind of rapid frequency-sweeping system block diagram of spectrum detector of the present invention.
Specific implementation mode：
Below in conjunction with the accompanying drawings, the present invention is described in further detail.
As described in Figure 2, the present invention provides a kind of rapid frequency-sweeping systems of spectrum detector, including the following contents：Including
A/D module, n Direct Digital Synthesizer DDS combinations, cic filter, HB filters, RBW filters, cordic moulds
Block, VBW modules, small bucket, small bucket data combiners blocks, big bucke, display module, wherein n is more than 1 odd number.
Every group of DDS is combined as, and the COS signal ends of a DDS connect I input terminal of frequency mixer, and the SIN signal ends of DDS connect frequency mixer II
Input terminal；The input terminal of frequency mixer I and frequency mixer II is also connected with A/D module output end；The output of frequency mixer I and frequency mixer II
End is separately connected a cic filter, and the output end of each cic filter connects the input terminal of HB filters, HB filters
Output end connects the input terminal of RBW filters, and the output ends of RBW filters connects cordic modules, cordic modules also with the roads n
The input terminal of VBW modules is connected, and the output end of a VBW module connects the input terminal of a small bucket, the small bucket's in the roads n
Input terminal connects small bucket data combiners blocks, and small bucket is also connected with the input terminal of big bucke, the output of big bucke
End connection display module.
If radio-frequency module output frequency is f (units:Hz intermediate-freuqncy signal), display points are K and (contain K big
Bucket), each big bucket contains L small bucket, and wide M (units are swept in upper application software setting:Hz), then each small
Bucket's sweeps wide f1=M/ (K*L) (unit:Hz).
According to the direction of signal stream, the effect of modules is as follows successively：
1. the analog signal of radio-frequency module output is mixed after AD is sampled with DDS, the frequency of the intermediate settings of DDS all the way is f
(unit:Hz), the frequency that other DDS are respectively set is f ± f1,......f±(n-1)*f1/ 2, that is, it is symmetrical arranged；
2. according to the resource requirement of the formed filter RBW of rear end, needs to carry out extraction frequency reducing to data, be filtered by CIC
Device and HB filters are completed, since the data input frequency of CIC is identical with the sampling clock of AD, so cannot be time-multiplexed, and
The frequency of the input data of HB filters has substantially reduced, and in order to save resource, time division multiplexing mould may be used in HB filters
Formula；
3.RBW filters are designed according to three three dB bandwidth, bandwidth selectivity and stopband attenuation indexs, complete waveform
Forming, the frequency of the input data of same RBW filters substantially reduced, and in order to save resource, RBW filters can also
Using time division multiplexing；；
4. directly invoking cordic modules finds out range value (for various detections) and phase value (for frequency counting), by
It is far below the sampling clock of AD in its input data, in order to save resource, cordic modules use time division multiplexing；
The effect of 5.VBW modules is smoothed to display result, it is really a low-pass filter, can be reduced
The peak level (but not reducing average noise level) of noise, reduces influence of the noise to observation useful signal.
6. signal is fetched in small bucket after VBW modules are smooth, it is noted that access has to wait for RBW filter numbers
After stablizing according to refresh all can, refresh stabilization time before be described in detail, such as table 2；
7. the data after bucket access small to the roads n are merged into all the way according to the principle of frequency from big to small, then big
The control of bucket signals is lower to carry out various detections, finally gives display module and displays data；
Upper layer software (applications) is as follows to the control procedure declaration of radio frequency：
1. upper layer software (applications), which calculates, sweeps wide, sweep time and display points (i.e. big bucket points), and according to above-mentioned three
A index calculates total small bucket points, and the small bucket numbers that each big bucket is included are notified to FPGA；
It is counted according to total small bucket to control radio frequency successively 2. being originally, is changed to count with total small bucket now
It reduces n times of number and controls radio frequency；
After 3.FPGA receives frequency sweep order, AD data are extracted and filtered in such a way that the roads n are developed simultaneously, then according to number
According to being separated out small bucket data between refreshing, and merge and uniformly give detection module, subsequent flow is identical with single channel.
The foregoing is only a preferred embodiment of the present invention, is not restricted to the present invention, for the technology of this field
For personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, any made by repair
Change, equivalent replacement, improvement etc., should be included within scope of the presently claimed invention.
Claims (4)
1. a kind of rapid frequency-sweeping system of spectrum detector, which is characterized in that including the following contents：It is a directly including A/D module, n
It is digital frequency synthesizer DDS combinations, cic filter, HB filters, RBW filters, cordic modules, VBW modules, small
Bucket, small bucket data combiners blocks, big bucke, display module, wherein n is more than 1 odd number；
Every group of DDS is combined as, and the COS signal ends of a DDS connect I input terminal of frequency mixer, the SIN signal ends connection mixing of DDS
II input terminal of device；The input terminal of frequency mixer I and frequency mixer II is also connected with A/D module output end；Frequency mixer I and frequency mixer II
Output end is separately connected a cic filter, the input terminal of the output end connection HB filters of each cic filter, HB filtering
The input terminal of the output end connection RBW filters of device, the output end of RBW filters connect cordic modules, and cordic modules are also
It is connected with the input terminal of the roads n VBW modules, the output end of a VBW module connects the input terminal of a small bucket, and the roads n are small
The input terminal of bucket connects small bucket data combiners blocks, and small bucket is also connected with the input terminal of big bucke, greatly
The output end of bucke connects display module；
The analog signal of radio-frequency module output is mixed after AD is sampled with DDS, and the frequency that intermediate DDS all the way is arranged is f (with radio frequency
The centre frequency of module output is identical), the frequency that other DDS are respectively set is f ± (n-1) * f1/ 2, that is, it is symmetrical arranged, f1
Width is swept for each small bucket；
According to the resource requirement of the formed filter RBW of rear end, need to carry out extraction frequency reducing to data, by cic filter and HB
Filter is completed, since the data input frequency of cic filter is identical with the sampling clock of AD, so cannot be time-multiplexed, and
The frequency of the input data of HB filters has substantially reduced, and in order to save resource, HB filters use time division multiplexing；
RBW filters are designed according to three three dB bandwidth, bandwidth selectivity and stopband attenuation indexs, complete the forming of waveform,
The frequency of the input data of same RBW filters has substantially reduced, and in order to save resource, RBW filters are also multiple using the time-division
Use pattern；
It directly invokes cordic modules and finds out range value and phase value, since its input data is far below the sampling clock of AD, be
Saving resource, cordic modules use time division multiplexing；
VBW modules are smoothed to display result；Signal is fetched in small bucket after VBW modules are smooth；
Data after bucket access small to the roads n are closed through too small bucket data combiners blocks according to the principle of frequency from big to small
And at all the way, various detections then is carried out under the control of big bucket signals, display module is finally given and displays data.
2. a kind of rapid frequency-sweeping system of spectrum detector according to claim 1, which is characterized in that each of described small
The width of sweeping of bucket is f1=M/ (K*L)；K is that display is counted, that is, contains K big bucket, and each big bucket contains L small
Wide M is swept in bucket, upper application software setting.
3. a kind of rapid frequency-sweeping method of spectrum detector, which is characterized in that including the following contents：
The analog signal of radio-frequency module output is mixed after AD is sampled with DDS, and the frequency of the intermediate settings of DDS all the way is f, other
The frequency that DDS is respectively set is f ± (n-1) * f1/ 2, that is, it is symmetrical arranged, f1 sweeps width for each small bucket's；
According to the resource requirement of the formed filter RBW of rear end, need to carry out extraction frequency reducing to data, by cic filter and HB
Filter is completed, since the data input frequency of cic filter is identical with the sampling clock of AD, so cannot be time-multiplexed, and
The frequency of the input data of HB filters has substantially reduced, and in order to save resource, HB filters use time division multiplexing；
RBW filters are designed according to three three dB bandwidth, bandwidth selectivity and stopband attenuation indexs, complete the forming of waveform,
The frequency of the input data of same RBW filters has substantially reduced, and in order to save resource, RBW filters are also multiple using the time-division
Use pattern；
It directly invokes cordic modules and finds out range value and phase value, since its input data is far below the sampling clock of AD, be
Saving resource, cordic modules use time division multiplexing；
VBW modules are smoothed to display result；Signal is fetched in small bucket after VBW modules are smooth；
Data after bucket access small to the roads n are closed through too small bucket data combiners blocks according to the principle of frequency from big to small
And at all the way, various detections then is carried out under the control of big bucket signals, display module is finally given and displays data.
4. a kind of rapid frequency-sweeping method of spectrum detector according to claim 3, which is characterized in that each of described small
The width of sweeping of bucket is f1=M/ (K*L)；K is that display is counted, that is, contains K big bucket, and each big bucket contains L small
Wide M is swept in bucket, upper application software setting.
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| WO2023197600A1 (en) * | 2022-04-14 | 2023-10-19 | 广州万码科技有限公司 | 5g signal spectrum detection method and apparatus, computer device, and storage medium |
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