CN111698036A - Multi-microwave signal frequency estimation method based on microwave photons - Google Patents

Multi-microwave signal frequency estimation method based on microwave photons Download PDF

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CN111698036A
CN111698036A CN202010510352.7A CN202010510352A CN111698036A CN 111698036 A CN111698036 A CN 111698036A CN 202010510352 A CN202010510352 A CN 202010510352A CN 111698036 A CN111698036 A CN 111698036A
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microwave
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frequency
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CN111698036B (en
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蔡晶晶
王亚宁
李超
李鹏
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Xidian University
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Abstract

The invention provides a microwave photon-based multi-microwave signal frequency estimation method, which aims to realize the simultaneous estimation of multiple microwave signal frequencies and improve the estimation precision. The method comprises the following implementation steps: constructing a microwave photonic system S; the receiving antenna unit receives microwave signals with a plurality of known frequencies; the first mach-zehnder modulator M1 performs intensity modulation on the microwave signal and the optical carrier signal; the optical filter bank B filters the first-order sideband signal for multiple times; the second mach-zehnder modulator M2 performs intensity modulation on the received time-delay microwave signal and the signal after B filtering; the carrier frequency signal measuring unit C measures the optical power of the carrier frequency signal; acquiring the carrier frequency signal light power of a microwave signal to be detected with intensity modulation frequency through a microwave photonic system S; and acquiring the frequency of the microwave signal to be detected. The invention adopts a system based on microwave photons to carry out frequency estimation of multiple microwave signals, and uses a formula of a convex optimization problem to process calculation data, thereby not only estimating the frequency of any number of microwave signals, but also improving the estimation efficiency and the estimation precision, and being applicable to target detection and passive positioning.

Description

Multi-microwave signal frequency estimation method based on microwave photons
Technical Field
The invention belongs to the technical field of photoelectric communication, and relates to a multi-microwave signal frequency estimation method which can be used for target detection and passive positioning.
Background
Microwave signals are electromagnetic wave signals having a wavelength between 0.1 mm and 1 m. Since the seventies of the last century, with the explosive development of photonic technologies and microwave technologies such as semiconductor lasers, high-speed photoelectric modulators, fiber optics, integrated photonics, microwave antennas, microwave monolithic integrated circuits and the like, a cross field, namely microwave photonics, which combines microwave and optics, has emerged. Microwave photonics is an emerging discipline, and studies are being made to utilize photonics methods to process microwave signals. The advantages of large bandwidth, small integrated volume, strong electromagnetic interference resistance and the like of the microwave photon technology provide a potential solution for processing millimeter-band microwave signals with large bandwidth and high frequency.
Because the frequency band of the radar administration source in the modern society is continuously enlarged, the difficulty is increased for the analysis and identification tasks of the detection system, and the frequency estimation of the traditional electronic method is limited by the electronic bottleneck of an electronic device, the received microwave signal is introduced into a microwave photon system for processing, so that the method is very promising for solving the problems. Compared with a frequency estimation scheme in the electronic field, the microwave signal frequency measurement scheme based on the microwave photons has the advantages of large instantaneous bandwidth, low loss, electromagnetic interference resistance and the like.
At present, two methods for realizing microwave signal frequency estimation by using a microwave photonics technology are available: one is that the received microwave signal is modulated to the optical carrier wave by the electro-optical modulator, and is processed by a certain optical signal processing unit to obtain an amplitude comparison function only related to the rate to be frequency estimated, so as to obtain the rate to be frequency estimated; the other method is to perform asynchronous sampling on the high-frequency microwave signal by using a frequency space compression method of asynchronous optical sampling, and analyze data to obtain the frequency of the signal to be detected. Based on the nyquist theorem, when the sampling rate reaches more than twice of the highest frequency of the signal to be measured, the frequency measured in the sampling data is the frequency of the signal to be measured. However, when the frequency of the signal is high, the measurement of the frequency cannot be realized due to the limitation of the slew rate of the device, and the asynchronous optical sampling method effectively solves the problem. Asynchronous optical sampling is to sample a high-frequency signal by using a signal with a lower frequency, so that the requirement on the sampling rate is reduced, and the sampling rate of the method can reach one tenth of the highest rate of a signal to be measured in general.
Microwave signal frequency measurement based on microwave photons is currently in the transition stage from experiments to engineering practical application, and has wide application prospects in the coming years. With the deep application of signal processing and the rapid development of electronic technology, the parameter estimation aiming at the space electromagnetic wave is an important research field in the signal processing, and the wide and important application background of the method in the fields of radar, sonar, communication, biomedicine, earthquake detection and the like is widely regarded.
In recent years, the frequency measurement technology research based on microwave photonics has the following characteristics:
(1) most of current frequency estimation schemes are focused on principle implementation and simulation verification, the frequency estimation range is small, frequency estimation errors mostly stay around 0.2GHz, and the schemes with high indexes, high performance and strong stability are few;
(2) the scheme mostly focuses on single frequency measurement. In some specific electromagnetic environments, a receiving end often receives multiple frequencies at the same time, but for a currently mainstream frequency estimation scheme, the scheme mostly stays in single-frequency measurement, and the scheme is not suitable for multiple-frequency measurement conditions.
In actual measurement, besides the factors such as loss and interference which are difficult to control, the setting of parameters of some devices, the size of microwave signals and the like all affect the measurement accuracy and range, for example:
(1) inputting the frequency of the microwave signal, and selecting a proper measurement range and measurement precision to more accurately measure the frequency carried by the microwave signal;
(2) the bias drift caused by the mach-zehnder modulator requires a complicated circuit to control its bias point when the mach-zehnder modulator is used, and a measurement error is introduced when the bias drift occurs.
The technology of using traditional electronic devices to directly process signals has some defects which are difficult to avoid, such as too large loss, high dispersion, inaccurate high-frequency measurement and the like. And the traditional signal processing system is large in size, lacks flexibility and is not suitable for being used in high-speed changing environments. For ultra-wideband signals, the traditional microwave signal processing based on electronic devices can only use a segmented processing method, and for parts which cannot be directly processed by medium-high frequency parts, the parts need to be converted into low-frequency signals by using an intermediate frequency technology, and then the low-frequency signals are converted into digital signals by using a digital sampling technology for processing. The intermediate frequency technology is particularly characterized in that a medium-high frequency signal is firstly divided into GHz segments and then is changed into a low-frequency signal by a mixing method, and the intermediate frequency technology has the technical defects that the problems of image frequency, cross modulation frequency, nonlinearity, frequency-dependent conversion gain and the like can occur. Meanwhile, when each signal segment cut from the broadband signal is processed by the method, a plurality of parallel systems are needed, for example, if the microwave frequency range to be measured is 0-40 GHz, 40 intermediate frequency systems with the bandwidth of 1GHz need to be used, which brings the disadvantages of high cost, large volume and the like. Compared with the traditional signal frequency estimation method, the method has the advantages of large estimation bandwidth, small loss, strong anti-interference capability, small system size and the like, can overcome the electronic bottleneck, and is suitable for complex electromagnetic environment. For example, the paper Pan S, Yao J.Photonics-Based Broadband Measurement [ J ]. Journal of lightwave Technology,2017,35(16): 3498-.
Disclosure of Invention
The present invention aims to provide a method for estimating frequencies of multiple microwave signals based on microwave photons, which aims to estimate frequencies of multiple microwave signals simultaneously and improve estimation accuracy. In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:
(1) constructing a microwave photonic system S:
constructing a microwave photonic system S, which comprises a receiving antenna unit R, a first Mach-Zehnder modulator M1, a second Mach-Zehnder modulator M2, a laser signal source L, an optical filter bank B consisting of a first optical filter B1 and a second optical filter B2 which are connected in parallel, and a carrier frequency signal measurement unit C consisting of a third optical filter B3 and an optical power meter W; one input end of the M1 is connected with the output end of the R, the other input end of the M1 is cascaded with the laser signal source L, and the output end of the M1 is cascaded with the optical filter bank B; one input end of the M2 is connected with the output end of the R through a microwave time delay line T, the other input end of the M2 is cascaded with the output end of the optical filter group B, and the output end of the M2 is cascaded with the third optical filter B3 and the optical power meter W in sequence; wherein: the frequency of an optical carrier signal of the laser signal source L is f;
(2) the receiving antenna unit receives microwave signals of a plurality of known frequencies:
the receiving antenna unit R receives N microwave signals with known frequencies and sequentially increased frequencies
Figure BDA0002528139800000031
The adjacent microwave signals have a frequency separation of △ f, wherein,
Figure BDA0002528139800000032
represents t1The frequency received at time R is
Figure BDA0002528139800000033
N is more than or equal to 1, and △ f is more than or equal to 500 MHz;
(3) the first mach-zehnder modulator M1 performs intensity modulation on the microwave signal and the optical carrier signal:
the first Mach-Zehnder modulator M1 receives a microwave signal of each known frequency for R
Figure BDA0002528139800000034
And an optical carrier signal v output by the laser signal source Lf(t1) Intensity modulation is carried out, and N groups of first-order sideband signals are obtained at the output end
Figure BDA0002528139800000041
Wherein
Figure BDA0002528139800000042
And
Figure BDA0002528139800000043
respectively represent frequencies of
Figure BDA0002528139800000044
And
Figure BDA0002528139800000045
a first-order sideband signal;
(4) the optical filter bank B filters the first order sideband signals a plurality of times:
optical filter bank B pairs N sets of first order sideband signals
Figure BDA0002528139800000046
Grouping and sequentially carrying out N times of filtering, specifically: when n is 1, B1 pairs in the first set of first order sideband signals
Figure BDA0002528139800000047
Filtering is carried out, and B2 pairs
Figure BDA0002528139800000048
Filtering is carried out, when N is 2 … N, B1 pairs the nth and all previous groups of first-order sideband signals
Figure BDA0002528139800000049
And a frequency greater than
Figure BDA00025281398000000410
Is filtered, B2 is
Figure BDA00025281398000000411
And a frequency less than
Figure BDA00025281398000000412
Filtering the first-order sideband signals to obtain N groups of filtered first-order sideband signals
Figure BDA00025281398000000413
(5) The second mach-zehnder modulator M2 performs intensity modulation on the received time-delayed microwave signal and the signal after B filtering:
the second Mach-Zehnder modulator M2 receives N microwave signals from the R through the microwave delay line T to form microwave signals
Figure BDA00025281398000000414
With B-filtered first-order sideband signals
Figure BDA00025281398000000415
Intensity modulation is carried out, N groups of output signals after intensity modulation are obtained at an output end, wherein tau represents time delay generated by T;
(6) the carrier frequency signal measurement unit C measures the carrier frequency signal optical power:
a third optical filter B3 in the carrier frequency signal measurement unit C filters each modulated group of output signals to obtain N groups of first output signals with the frequency f, and measures the optical power of the carrier frequency signal of each group of filtering results by an optical power meter W to obtain N groups of optical powers of the carrier frequency signal
Figure BDA00025281398000000416
(7) Obtaining the carrier frequency signal light power of the microwave signal to be detected with the intensity modulation frequency through a microwave photon system S:
(7a) the receiving antenna unit R receives N microwave signals v with frequencies to be measured1(t2),v2(t2),…,vn(t2),…,vN(t2) Wherein v isn(t2) Represents t2The received frequency received at time R is fnThe nth microwave signal of (1);
(7b) m1 pairs R received microwave signals v with each frequency to be measuredn(t2) And an optical carrier signal v output by the laser signal source Lf(t2) Intensity modulation is carried out, and N groups of first-order sideband signals v are obtained at the output endf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2)；…；vf-n(t2),vf+n(t2)；…；vf-N(t2),vf+N(t2) Wherein v isf-n(t2) And vf+n(t2) Respectively representing frequencies f-fnAnd f + fnA first-order sideband signal;
(7c) optical filter bank B pairs N sets of first order sideband signals vf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2)；…；vf-n(t2),vf+n(t2)；…；vf-N(t2),vf+N(t2) Grouping and sequentially carrying out N times of filtering, specifically: when n is 1, B1 pairs v in the first set of first order sideband signalsf-1(t2) Filtering, B2 for vf+1(t2) Filtering is carried out, when N is 2 … N, B1 pairs v in the first-order sideband signals of the nth group and all previous groupsf-n(t2) And a frequency greater than f-fnB2 filters vf+1(t2) And frequency less than f + fnIs filtered to obtain N sets of filtered first-order sideband signals v'f-1(t2),v'f+1(t2)；v'f-2(t2),v'f+2(t2)；…；v'f-n(t2),v'f+n(t2)；…；v'f-N(t2),v'f+N(t2)；
(7d) Let τ be τ1,τ2,…,τl,…,τMThen the M2 received is delayed by TThe microwave signal at time is expressed as:
A1(t2),A2(t2),…,Al(t2),…,AM(t2)
Al(t2)＝v1(t2+τl),v2(t2+τl),…,vn(t2+τl),…,vN(t2+τl)
wherein tau islRepresents the l modification of tau, M represents the number of modifications, and M is more than or equal to 3;
(7e) microwave signal A output by M2 to T1(t2),A2(t2),…,Al(t2),…,AM(t2) Respectively with filtered N sets of first-order sideband signals v'f-1(t1),v'f+1(t1)；v'f-2(t1),v'f+2(t1)；…；v'f-n(t1),v'f+n(t1)；…；v'f-N(t1),v'f+N(t1) Carrying out intensity modulation, and obtaining M N groups of output signals after intensity modulation at an output end;
(7f) a third optical filter B3 in the carrier frequency signal measurement unit C filters each of N groups of output signals of M groups of output signals after intensity modulation, so as to obtain N groups of second output signals with frequency f, and measures the optical power of the carrier frequency signal of each group of filtering results by an optical power meter W, so as to obtain M groups of carrier frequency signal optical powers:
P1，P2，…，Pl，…，PM
Pl＝pl1,pl2,…,pln,…,plN；
(8) acquiring the frequency of a microwave signal to be detected:
(8a) the optical power of the carrier frequency signal obtained in the step (6) is passed
Figure BDA0002528139800000061
Calculating an empirical value O of a constant in an empirical formula of optical powernThen N sets of carrier frequency signal optical power
Figure BDA0002528139800000062
The empirical value of the constant in the corresponding empirical formula of the optical power is O1,O2,…,On,…,ONAnd p in step (7f)lnAnd OnAs the quotient data QlnThen, the data Q is calculated by all the ratio data1n,Q2n,…,Qln,…,QMnCalculating the actual observation vector Yn：
Yn＝[Q1n,Q2n,…,Qln,…,QMn]T
Wherein [ ·]TRepresenting a transpose;
(8b) through Z
Figure BDA0002528139800000063
And
Figure BDA0002528139800000064
for actual observation vector YnRemolding to obtain an actual observation vector Y after noise eliminationn'：
Figure BDA0002528139800000065
Wherein
Figure BDA0002528139800000066
Is a sparse representation coefficient vector of (1-p),
Figure BDA0002528139800000067
a matrix of dimension M × N is represented,
Figure BDA0002528139800000068
Figure BDA0002528139800000069
Figure BDA00025281398000000610
(8c) using the formula of the convex optimization problem and passing through Yn' calculating the microwave signal to be measured vn(t2) Frequency f ofn。
Compared with the prior art, the invention has the following advantages:
1. according to the invention, the empirical value of the constant in the N optical power empirical formulas corresponding to the optical powers of the N groups of carrier frequency signals is obtained through N microwave signals with known frequencies received by one receiving antenna unit, and the frequency of the microwave signals with unknown frequencies is estimated through the N empirical values, so that the defect that only one signal frequency can be estimated at a time in the prior art is avoided, and the estimation efficiency is effectively improved.
2. The method processes data by using the formula of the convex optimization problem, calculates the frequency of the microwave signal to be measured, reduces calculation errors, and effectively improves estimation precision compared with the prior art.
Drawings
FIG. 1 is a flow chart of an implementation of the present invention;
FIG. 2 is a schematic diagram of the structure of a microwave photonic system S constructed in the present invention;
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments.
Referring to fig. 1, the present invention includes the steps of:
step 1) constructing a microwave photonic system S as shown in FIG. 2:
constructing a microwave photonic system S, which comprises a receiving antenna unit R, a first Mach-Zehnder modulator M1, a second Mach-Zehnder modulator M2, a laser signal source L, an optical filter bank B consisting of a first optical filter B1 and a second optical filter B2 which are connected in parallel, and a carrier frequency signal measurement unit C consisting of a third optical filter B3 and an optical power meter W; the first mach-zehnder modulator M1 is in a carrier suppression state, the parallel structure formed by the first optical filter B1 and the second optical filter B2 is used for filtering a first-order sideband signal generated after a microwave signal is modulated by the first mach-zehnder modulator M1, the second mach-zehnder modulator M2 is in a carrier suppression state, the third optical filter B3 is used for filtering a carrier frequency signal generated after the microwave signal is modulated by the second mach-zehnder modulator M2, and the optical power meter W is used for obtaining an optical power value of the microwave signal; one input end of the M1 is connected with the output end of the R, the other input end of the M1 is cascaded with the laser signal source L, and the output end of the M1 is cascaded with the optical filter bank B; one input end of the M2 is connected with the output end of the R through a microwave time delay line T, the other input end of the M2 is cascaded with the output end of the optical filter group B, and the output end of the M2 is cascaded with the third optical filter B3 and the optical power meter W in sequence; wherein: the frequency of an optical carrier signal of the laser signal source L is f;
step 2) the receiving antenna unit receives microwave signals with known frequency:
the receiving antenna unit R receives 2 frequencies of
Figure BDA0002528139800000071
Of microwave signal
Figure BDA0002528139800000072
The frequency interval of adjacent microwave signals is △ f, which is 2 GHz;
step 3) the first mach-zehnder modulator M1 modulates the intensities of the microwave signal and the optical carrier signal:
the first Mach-Zehnder modulator M1 receives a microwave signal for each known azimuth of arrival at R
Figure BDA0002528139800000081
And an optical carrier signal v output by the laser signal source Lf(t1) Intensity modulation is performed whereby the electrical signal is represented in the form of an optical signal, while 2 sets of first order sideband signals are generated that are symmetric about the carrier frequency signal due to the first mach-zehnder modulator M1 being in a carrier-suppressed state
Figure BDA0002528139800000082
Step 4), the optical filter bank B carries out multiple filtering on the first-order sideband signals:
because the frequency estimation of the microwave signal is performed on multiple sets of signals simultaneously, multiple filtering is required in this step. Optical filter bank B vs. 2 sets of first order sideband signals
Figure BDA0002528139800000083
Grouping and sequentially carrying out 2 times of filtering, specifically: when n is 1, B1 pairs in the first set of first order sideband signals
Figure BDA0002528139800000084
Filtering is carried out, and B2 pairs
Figure BDA0002528139800000085
Filtering is performed, and when n is 2, B1 is used to filter the first order sideband signals of the 2 nd and 1 st groups
Figure BDA0002528139800000086
Filtering is carried out, and B2 pairs
Figure BDA0002528139800000087
Filtering to obtain 2 sets of first-order sideband signals
Figure BDA0002528139800000088
Wherein, when the filtering is performed for the first time, it can be measured
Figure BDA0002528139800000089
And
Figure BDA00025281398000000810
at the second filtering,
Figure BDA00025281398000000811
and
Figure BDA00025281398000000812
frequency information ofAnd
Figure BDA00025281398000000813
and
Figure BDA00025281398000000814
is measured in combination, but because
Figure BDA00025281398000000815
And
Figure BDA00025281398000000816
has been measured, and can therefore be derived
Figure BDA00025281398000000817
And
Figure BDA00025281398000000818
the frequency of (d);
step 5) the second mach-zehnder modulator M2 performs intensity modulation on the received time-delay microwave signal and the signal after B filtering:
because the first-order sideband signals obtained at the output end of the first mach-zehnder modulator M1 are limited and are not enough to meet the number requirement of final microwave signal frequency estimation, a new group of microwave signals obtained by adding time delay to a group of microwave signals received by one antenna can be obtained by introducing the microwave time delay line T so as to be used for intensity modulation of the second mach-zehnder modulator M2. The second Mach-Zehnder modulator M2 receives 2 microwave signals from the R and forms microwave signals after passing through the microwave delay line T
Figure BDA00025281398000000819
With B-filtered first-order sideband signals
Figure BDA00025281398000000820
Intensity modulation is carried out, and 2 groups of output signals which are symmetrical about the carrier frequency signal and subjected to intensity modulation are obtained at the output end because the second Mach-Zehnder modulator M2 is in a carrier suppression stateNumber, where τ represents the time delay incurred by T;
step 6) the carrier frequency signal measuring unit C measures the carrier frequency signal optical power:
because the frequency estimation of the microwave signal is performed on multiple sets of signals simultaneously, multiple filtering is required in this step. A third optical filter B3 in the carrier frequency signal measurement unit C filters each modulated group of output signals to obtain 2 groups of first output signals with the frequency f, and measures the carrier frequency signal optical power of each group of filtering results by an optical power meter W to obtain 2 groups of carrier frequency signal optical powers
Figure BDA0002528139800000091
Step 7) obtaining the carrier frequency signal optical power of the microwave signal to be detected with the intensity modulation frequency through the microwave photonic system S:
(7a) the receiving antenna unit R receives 2 frequencies f1,f2Assuming a microwave signal v to be measured1(t2),v2(t2) Wherein f is1,f2The actual setting value of (3) is 3GHz and 5 GHz;
(7b) m1 pair R received microwave signal v with frequency to be measured1(t2),v2(t2) And an optical carrier signal v output by the laser signal source Lf(t2) Intensity modulation is carried out, and 2 groups of first-order sideband signals v are obtained at the output endf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2)；
(7c) Optical filter bank B versus 2 sets of first order sideband signals vf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2) Grouping and sequentially carrying out 2 times of filtering, specifically: when n is 1, B1 pairs v in the first set of first order sideband signalsf-1(t2) Filtering, B2 for vf+1(t2) Filtering is performed, and when n is 2, B1 pairs v in the first order sideband signals of the 2 nd and 1 st groupsf-2(t2),vf-1(t2) Filtering, B2 for vf+2(t2),vf+1(t2) Filtering to obtain N groups of filtered first-order sideband signals v'f-1(t2),v'f+1(t2)；v'f-2(t2),v'f+2(t2)；
(7d) Let τ be τ1,τ2,…,τl,…,τ5Then the T-delayed microwave signal received by M2 is expressed as:
A1(t2),A2(t2),…,Al(t2),…,A5(t2)
A1(t2)＝v1(t2+τ1),v2(t2+τ1)
A2(t2)＝v1(t2+τ2),v2(t2+τ2)
Al(t2)＝v1(t2+τl),v2(t2+τl)
A5(t2)＝v1(t2+τ5),v2(t2+τ5)
wherein tau islDenotes the l modification to τ, τ1＝0.005，τ2＝0.01，τ3＝0.015，τ4＝0.02，τ5＝0.025；
(7e) Microwave signal A output by M2 to T1(t2),A2(t2),…,Al(t2),…,A5(t2) Respectively with filtered 2 sets of first-order sideband signals v'f-1(t1),v'f+1(t1)；v'f-2(t1),v'f+2(t1) Intensity modulation is carried out, and 5 output signals of 2 groups are obtained at the output end after intensity modulation;
(7f) a third optical filter B3 in the carrier frequency signal measurement unit C filters each of N groups of output signals of M groups of output signals after intensity modulation, so as to obtain N groups of second output signals with frequency f, and measures the optical power of the carrier frequency signal of each group of filtering results by an optical power meter W, so as to obtain M groups of carrier frequency signal optical powers:
P1，P2，…，Pl，…，P5
Pl＝pl1,pl2；
step 8) obtaining the frequency of the microwave signal to be detected:
(8a) the optical power of the carrier frequency signal obtained in the step (6) is passed
Figure BDA0002528139800000101
Calculating an empirical value O of a constant in an empirical formula of optical powern2 sets of carrier frequency signal optical power
Figure BDA0002528139800000102
The empirical value of the constant in the corresponding empirical formula of the optical power is O1,O2And p in step (7f)l1And O1As the quotient data Ql1，pl2And O2As the quotient data Ql2Then, the data Q is calculated by all the ratio data1n,Q2n,…,Qln,…,Q5nCalculating the actual observation vector Yn：
Y1＝[Q11,Q21,…,Ql1,…,Q51]T
Y2＝[Q12,Q22,…,Ql2,…,Q52]T
Wherein [ ·]TRepresenting a transpose;
the empirical value O of the constant in the optical power calculation formula1,O2,…,On,…,ONThe calculation formulas are respectively as follows:
Figure BDA0002528139800000111
Figure BDA0002528139800000112
wherein, oc represents a direct ratio,
Figure BDA0002528139800000113
as microwave signals
Figure BDA0002528139800000114
The angular frequency of (a) of (b),
Figure BDA0002528139800000115
as microwave signals
Figure BDA0002528139800000116
The angular frequency of (a) of (b),
Figure BDA0002528139800000117
(8b) by passing
Figure BDA0002528139800000118
And
Figure BDA0002528139800000119
for actual observation vector Y1And Y2Reshaping to obtain Y after noise suppression1' and Y2'：
Figure BDA00025281398000001110
Figure BDA00025281398000001111
Wherein
Figure BDA00025281398000001112
Is a sparse representation coefficient vector of (1-p),
Figure BDA00025281398000001113
a matrix of dimension 5 × 2 is represented,
Figure BDA00025281398000001114
Figure BDA00025281398000001115
Figure BDA00025281398000001116
Figure BDA00025281398000001117
Figure BDA00025281398000001118
(8c) in order to improve the accuracy of the estimation of the direction of arrival angle, the formula of the convex optimization problem is adopted and Y is used1' and Y2' calculating the microwave signal to be measured v1(t2) And v2(t2) Frequency f of1＝3GHz，f1The simulation result shows that the error between the obtained signal frequency and the actually set microwave signal frequency is 0, wherein the convex optimization problem has the formula:
Figure BDA00025281398000001119
wherein | · | purple1Represents 1-norm, | · | non-woven phosphor2Representing a 2-norm, representing an arbitrarily small number.

Claims (3)

1. A multi-microwave signal frequency estimation method based on microwave photons is characterized by comprising the following steps:
(1) constructing a microwave photonic system S:
constructing a microwave photonic system S, which comprises a receiving antenna unit R, a first Mach-Zehnder modulator M1, a second Mach-Zehnder modulator M2, a laser signal source L, an optical filter bank B consisting of a first optical filter B1 and a second optical filter B2 which are connected in parallel, and a carrier frequency signal measurement unit C consisting of a third optical filter B3 and an optical power meter W; one input end of the M1 is connected with the output end of the R, the other input end of the M1 is cascaded with the laser signal source L, and the output end of the M1 is cascaded with the optical filter bank B; one input end of the M2 is connected with the output end of the R through a microwave time delay line T, the other input end of the M2 is cascaded with the output end of the optical filter group B, and the output end of the M2 is cascaded with the third optical filter B3 and the optical power meter W in sequence; wherein: the frequency of an optical carrier signal of the laser signal source L is f;
(2) the receiving antenna unit receives microwave signals of a plurality of known frequencies:
the receiving antenna unit R receives N microwave signals with known frequencies and sequentially increased frequencies
Figure FDA0002528139790000011
The adjacent microwave signals have a frequency separation of △ f, wherein,
Figure FDA0002528139790000012
represents t1The frequency received at time R is
Figure FDA0002528139790000013
N is more than or equal to 1, and △ f is more than or equal to 500 MHz;
(3) the first mach-zehnder modulator M1 performs intensity modulation on the microwave signal and the optical carrier signal:
the first Mach-Zehnder modulator M1 receives a microwave signal of each known frequency for R
Figure FDA0002528139790000014
And an optical carrier signal v output by the laser signal source Lf(t1) Intensity modulation is carried out, and N groups of first-order sideband signals are obtained at the output end
Figure FDA0002528139790000015
Wherein
Figure FDA0002528139790000016
And
Figure FDA0002528139790000017
respectively represent frequencies of
Figure FDA0002528139790000018
And
Figure FDA0002528139790000019
a first-order sideband signal;
(4) the optical filter bank B filters the first order sideband signals a plurality of times:
optical filter bank B pairs N sets of first order sideband signals
Figure FDA00025281397900000110
Grouping and sequentially carrying out N times of filtering, specifically: when n is 1, B1 pairs in the first set of first order sideband signals
Figure FDA00025281397900000111
Filtering is carried out, and B2 pairs
Figure FDA00025281397900000112
Filtering is carried out, when N is 2 … N, B1 pairs the nth and all previous groups of first-order sideband signals
Figure FDA00025281397900000113
And a frequency greater than
Figure FDA00025281397900000114
Is filtered, B2 is
Figure FDA00025281397900000115
And a frequency less than
Figure FDA00025281397900000116
Filtering the first-order sideband signals to obtain N groups of filtered first-order sideband signals
Figure FDA0002528139790000021
(5) The second mach-zehnder modulator M2 performs intensity modulation on the received time-delayed microwave signal and the signal after B filtering:
the second Mach-Zehnder modulator M2 receives N microwave signals from the R through the microwave delay line T to form microwave signals
Figure FDA0002528139790000022
With B-filtered first-order sideband signals
Figure FDA0002528139790000023
Intensity modulation is carried out, N groups of output signals after intensity modulation are obtained at an output end, wherein tau represents time delay generated by T;
(6) the carrier frequency signal measurement unit C measures the carrier frequency signal optical power:
a third optical filter B3 in the carrier frequency signal measurement unit C filters each modulated group of output signals to obtain N groups of first output signals with the frequency f, and measures the optical power of the carrier frequency signal of each group of filtering results by an optical power meter W to obtain N groups of optical powers of the carrier frequency signal
Figure FDA0002528139790000024
(7) Obtaining the carrier frequency signal light power of the microwave signal to be detected with the intensity modulation frequency through a microwave photon system S:
(7a) the receiving antenna unit R receives N microwave signals v with frequencies to be measured1(t2),v2(t2),…,vn(t2),…,vN(t2) Wherein v isn(t2) Represents t2The received frequency received at time R is fnThe nth microwave signal of (1);
(7b) m1 pairs R received microwave signals v with each frequency to be measuredn(t2) And an optical carrier signal v output by the laser signal source Lf(t2) Intensity modulation is carried out, and N groups of first-order edges are obtained at the output endSignal v with signalf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2)；…；vf-n(t2),vf+n(t2)；…；vf-N(t2),vf+N(t2) Wherein v isf-n(t2) And vf+n(t2) Respectively representing frequencies f-fnAnd f + fnA first-order sideband signal;
(7c) optical filter bank B pairs N sets of first order sideband signals vf-1(t2),vf+1(t2)；vf-2(t2),vf+2(t2)；…；vf-n(t2),vf+n(t2)；…；vf-N(t2),vf+N(t2) Grouping and sequentially carrying out N times of filtering, specifically: when n is 1, B1 pairs v in the first set of first order sideband signalsf-1(t2) Filtering, B2 for vf+1(t2) Filtering is carried out, when N is 2 … N, B1 pairs v in the first-order sideband signals of the nth group and all previous groupsf-n(t2) And a frequency greater than f-fnB2 filters vf+n(t2) And frequency less than f + fnIs filtered to obtain N sets of filtered first-order sideband signals v'f-1(t2),v'f+1(t2)；v'f-2(t2),v'f+2(t2)；…；v'f-n(t2),v'f+n(t2)；…；v'f-N(t2),v'f+N(t2)；
(7d) Let τ be τ1,τ2,…,τl,…,τMThen the T-delayed microwave signal received by M2 is expressed as:
A1(t2),A2(t2),…,Al(t2),…,AM(t2)
Al(t2)＝v1(t2+τl),v2(t2+τl),…,vn(t2+τl),…,vN(t2+τl)
wherein tau islRepresents the l modification of tau, M represents the number of modifications, and M is more than or equal to 3;
(7e) microwave signal A output by M2 to T1(t2),A2(t2),…,Al(t2),…,AM(t2) Respectively with filtered N sets of first-order sideband signals v'f-1(t1),v'f+1(t1)；v'f-2(t1),v'f+2(t1)；…；v'f-n(t1),v'f+n(t1)；…；v'f-N(t1),v'f+N(t1) Carrying out intensity modulation, and obtaining M N groups of output signals after intensity modulation at an output end;
(7f) a third optical filter B3 in the carrier frequency signal measurement unit C filters each of N groups of output signals of M groups of output signals after intensity modulation, so as to obtain N groups of second output signals with frequency f, and measures the optical power of the carrier frequency signal of each group of filtering results by an optical power meter W, so as to obtain M groups of carrier frequency signal optical powers:
P1，P2，…，Pl，…，PM
Pl＝pl1,pl2,…,pln,…,plN；
(8) acquiring the frequency of a microwave signal to be detected:
(8a) the optical power of the carrier frequency signal obtained in the step (6) is passed
Figure FDA0002528139790000031
Calculating an empirical value O of a constant in an empirical formula of optical powernThen N sets of carrier frequency signal optical power
Figure FDA0002528139790000032
The empirical value of the constant in the corresponding empirical formula of the optical power is O1,O2,…,On,…,ONAnd p in step (7f)lnAnd OnQuotient of (1)As ratio data QlnThen, the data Q is calculated by all the ratio data1n,Q2n,…,Qln,…,QMnCalculating the actual observation vector Yn：
Yn＝[Q1n,Q2n,…,Qln,…,QMn]T
Wherein [ ·]TRepresenting a transpose;
(8b) by passing
Figure FDA0002528139790000033
And
Figure FDA0002528139790000034
for actual observation vector YnRemodeling to obtain an actual observation vector Y 'after noise elimination'n：
Figure FDA0002528139790000035
Wherein
Figure FDA0002528139790000041
Is a sparse representation coefficient vector of (1-p),
Figure FDA0002528139790000042
a matrix of dimension M × N is represented,
Figure FDA0002528139790000043
Figure FDA0002528139790000044
Figure FDA0002528139790000045
(8c) adopting a formula of convex optimization problem and passing through Y'nCalculating the microwave signal v to be measuredn(t2) Frequency f ofn。
2. The method of claim 1, wherein the empirical value O of the constant in the optical power calculation formula in step (8a) is an empirical value O1,O2,…,On,…,ONThe calculation formulas are respectively as follows:
Figure FDA0002528139790000046
Figure FDA0002528139790000047
Figure FDA0002528139790000048
Figure FDA0002528139790000049
Figure FDA00025281397900000410
Figure FDA00025281397900000411
wherein, oc represents a direct ratio,
Figure FDA00025281397900000412
as microwave signals
Figure FDA00025281397900000413
The angular frequency of (a) of (b),
Figure FDA00025281397900000414
3. the method for microwave photon-based frequency estimation of multiple microwave signals according to claim 1, wherein the convex optimization problem in step (8c) has the formula:
Figure FDA00025281397900000415
Figure FDA00025281397900000416
Figure FDA00025281397900000417
Figure FDA00025281397900000418
wherein | · | purple1Represents 1-norm, | · | non-woven phosphor2Representing a 2-norm, representing an arbitrarily small number.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115208463A (en) * 2021-04-09 2022-10-18 西安电子科技大学 Optical sampling multi-target frequency measurement method based on phase spectrum analysis
CN116131964A (en) * 2022-12-26 2023-05-16 西南交通大学 Microwave photon-assisted space-frequency compressed sensing frequency and DOA estimation method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105391460A (en) * 2014-06-30 2016-03-09 英特尔Ip公司 Receiver, transceiver and method for receiving signal
US20160329967A1 (en) * 2015-05-04 2016-11-10 Zte Corporation Qam vector signal generation by external modulator
CN108880648A (en) * 2018-07-06 2018-11-23 西安电子科技大学 Ultra-broadband signal frequency estimating methods based on microwave photon array

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105391460A (en) * 2014-06-30 2016-03-09 英特尔Ip公司 Receiver, transceiver and method for receiving signal
US20160329967A1 (en) * 2015-05-04 2016-11-10 Zte Corporation Qam vector signal generation by external modulator
CN108880648A (en) * 2018-07-06 2018-11-23 西安电子科技大学 Ultra-broadband signal frequency estimating methods based on microwave photon array

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115208463A (en) * 2021-04-09 2022-10-18 西安电子科技大学 Optical sampling multi-target frequency measurement method based on phase spectrum analysis
CN115208463B (en) * 2021-04-09 2024-01-26 西安电子科技大学 Optical sampling multi-target frequency measurement method based on phase spectrum analysis
CN116131964A (en) * 2022-12-26 2023-05-16 西南交通大学 Microwave photon-assisted space-frequency compressed sensing frequency and DOA estimation method

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