CN111541492A - Multichannel expanded ultra-wideband radio-frequency channelized receiving device and implementation method - Google Patents

Abstract

The invention provides a multi-channel expanded ultra-wideband radio frequency channelized receiving device and a realization method. The LD is divided into upper and lower channels. The upper channel is connected to a signal optical comb generating module and then connected to the MZM, the MZM is connected to the WDM1, and the output end of the WDM1 is divided into two channels. It is multi-channel; the lower channel of the LD output is connected to IM and then connected to OBPF. OBPF is connected to the local oscillator optical comb generation module and then connected to WDM2. The output of WDM2 is divided into multiple channels. WDM2 and WDM1 respectively enter OHC, OHC and two A BPD is connected, and the BPD is connected to the ADC. The invention obtains an ideal 7-line optical comb by setting the three DC bias voltages in the DPMZM, and then easily doubles the number of comb teeth of the optical frequency comb by means of double-drive cascade, so as to realize the multi-channelization of the receiver. For the purpose of channel expansion, the reasonable frequency shift of the local oscillator optical comb can become the same intermediate frequency when each independent channel is down-converted, which greatly simplifies the complexity of the subsequent ADC and effectively simplifies the channelized receiver system.

Description

A multi-channel extended ultra-wideband radio frequency channelized receiving device and implementation method

technical field

The invention relates to the technical field of optical communication and microwave technology, and mainly utilizes microwave photonics technology to realize channelized reception of ultra-wideband, multi-frequency mixed radio frequency signals.

Background technique

With the rapid development of wireless communication technology, whether it is multi-service broadband communication in the civil field or electronic warfare in the military field, new challenges have been put forward to the receiving performance of the receiver, and the realization of multi-form, multi-frequency, large instantaneous reception Indicators such as bandwidth have become an inevitable trend in the development of receivers. Because the existing analog-to-digital converter (ADC) is limited by sampling rate and bandwidth, it cannot realize the reception and processing of ultra-wideband signals, while the channelized receiver can divide the received ultra-wideband signal into multiple sub-channels, each sub-channel After the down-conversion is implemented independently, it is processed by the ADC, which greatly reduces the processing pressure of the ADC, and can effectively realize the simultaneous reception and processing of ultra-wideband and multi-frequency signals. Traditional channelized receivers are limited by many electronic bottlenecks such as electromagnetic interference, high power consumption, and large size and quality of electronic devices, making it difficult to meet the development needs of future ultra-wideband communications. As an emerging discipline, microwave photonics can combine the advantages of photonics with large instantaneous bandwidth, strong anti-electromagnetic interference ability, small size and light weight of optoelectronic devices with channelized receivers, and effectively further improve the performance of channelized receivers. At present, microwave photonic channelized receivers have become a research hotspot.

At present, most of the reported microwave photonic channelized receivers adopt the channelized receiving scheme of optical frequency comb. In such schemes, the number of comb teeth and flatness of the optical frequency comb directly affect the receiving performance of the channelized receiver. Optical frequency combs with a large number of combs and good flatness are often difficult to take into account. Usually, the number of combs with a large number of combs has poor flatness, and the number of combs with ideal flatness is small, which has become a channel expansion of channelized receivers. big problem.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the present invention provides a multi-channel extended ultra-wideband radio frequency channelized receiving device and an implementation method. The invention proposes an ultra-wideband radio frequency signal receiving with multi-channel expansion by using parallel dual-horsepower modulator (DPMZM) cascade and wavelength division multiplexer (WDM), only two DPMZMs are needed to realize 49 lines The generation of the optical frequency comb not only has a large number of comb teeth and good flatness, but also the comb teeth interval of the optical frequency comb is flexibly adjustable, and the working range of the channelized receiver can be flexibly realized according to the specific parameters of the corresponding WDM. Therefore, the present invention effectively solves the problem of limited number of sub-channels that can be used to simultaneously receive different signals faced by the current channelized receiver, greatly improves the instantaneous receiving bandwidth of the receiver, and has strong practical value and significance.

The technical scheme adopted by the present invention to solve its technical problems is:

A multi-channel extended ultra-wideband radio frequency channelized receiving device, comprising a laser diode (LD), a dual-parallel Mach-Zehnder Modulator (DPMZM), a radio frequency signal source (RF), and a local oscillator signal source (LO), Intensity Modulator (IM), Optical Band Pass Filter (OBPF), Horse Boost Modulator (MZM), Wavelength Division Multiplexer (WDM), Optical Quadrature Coupler (OHC) and Balanced Detector ( BPD); LD output power is divided into upper and lower paths, the upper path is connected to the input end of the signal optical comb generation module, and the output end of the signal optical comb generation module is connected to the input end of the MZM; the broadband RF signal RF3 is loaded on the RF input of the MZM The output end of MZM is connected with the input end of WDM1, and the output end of WDM1 is divided into multiple channels; The local oscillator optical comb generation module is connected, the output end of the local oscillator optical comb generation module is connected to the input end of WDM2, the output end of WDM2 is divided into multiple channels, and each branch of the output end of WDM2 is connected with each branch of the output end of WDM1 one by one After corresponding, they enter different OHCs as input signals, that is, WDM1 and WDM2 divide the received 49 optical combs into 49 independent frequency channels according to the frequency interval, and the first channel in WDM1 is combined with the first channel in WDM2. Then enter the OHC as an input signal, the second channel in WDM1 and the second channel in WDM2 are combined at one time as another set of input signals into another OHC, and so on, the output end of the OHC is connected to two BPDs, one The BPD demodulates the I channel signal, the other BPD demodulates the Q channel signal, and the output end of the BPD is connected to the ADC.

In the signal comb generation module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected to the RF signal source, the other RF input port MZMb is empty; the RF input end MZMa of DPMZM1 is connected to the RF signal RF1, the RF input end MZMa of DPMZM2 is connected to the RF signal RF2, and the output end of DPMZM1 is connected to the input of DPMZM2 The output end of DPMZM2 is connected with the input end of MZM;

In the local oscillator optical comb module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected with the RF signal source, and the other RF input port MZMb is unloaded; the local oscillator signal LO ₁ is connected with the RF input end MZMa in DPMZM3, the RF input end in DPMZM4 is connected with the local oscillator signal LO ₂ , and the output of DPMZM3 The terminal is connected with the input terminal of DPMZM4, and the output terminal of DPMZM4 is connected with the input terminal of WDM2.

The present invention also provides an implementation method of a multi-channel extended ultra-wideband radio frequency channelized receiving device, comprising the following steps:

Step 1: The single-carrier laser output by the laser source is expressed as: E _in (t)=E ₀ exp(jω _c t), and the two radio frequency signals RF1 and RF2 generated by the radio frequency signal source are expressed as: s(t) ₁ = V ₁ sin(ω ₁ t), s(t) ₂ =V ₂ sin(ω ₂ t), where E ₀ is the electric field strength of the optical carrier, ω _c is the angular frequency of the optical carrier, s(t) ₁ and s(t) ₂ are two radio frequency signals, V ₁ and V ₂ are the amplitudes of the two radio frequency signals, respectively, and ω ₁ and ω ₂ are the angular frequencies of the two radio frequency signals respectively;

Step 2: The single-carrier laser output by the LD is input to the optical input port of the DPMZM1 on the upper channel, and the RF signal RF1 output by the RF signal source is input to the RF input port of the DPMZM1. The output of the DPMZM1 is expressed as:

Among them, A=πV _1a /2V _π , B=πV ₀ /2V _π , V _π represents the half-wave voltage of MZM or DPMZM, f represents the frequency of RF1, V ₀ is the voltage of the added RF signal RF1, and V _1a is the DPMZM1 The DC bias of the MZMa, V _1b is the DC bias of the MZMb of the DPMZM1, V _1c is the main DC bias of the DPMZM, J _n (x) represents the nth order Bessel function, when the

To obtain an ideal 7-line optical comb, the equations (1) and (2) are simultaneously combined, and then the values of V _1a , V _1b , and V _1c are obtained when the 7-line optical comb is generated;

否则会出现梳齿混叠影响宽带信号的调制效果，因此DPMZM2输出49线信号光梳；Step 3: The 7-line optical comb output by DPMZM1 enters the optical input port of DPMZM2, and the RF signal RF2 output from the RF signal source is input to the RF input port of DPMZM2. Similarly, set the DC bias voltages V _2a , V _2b , V in DPMZM2 The value of _2c , then each optical frequency comb output by DPMZM1 is used as a new optical carrier to be modulated into a 7-line optical comb again. At this time, the frequency value of the input RF signal RF2 is the size of RF1.

Otherwise, comb aliasing will affect the modulation effect of the broadband signal, so the DPMZM2 outputs a 49-line signal optical comb;

Step 4: The 49-line signal optical comb output by DPMZM2 enters the MZM. In the MZM, the broadband RF signal RF3 modulates the 49-line signal optical comb, and sets the DC bias of the MZM, so that the MZM works at the minimum transmission point, and performs bilateral carrier suppression. with modulation;

Step 5: Each modulated signal output by the MZM is divided into independent sub-channels after entering the WDM1;

Step 6: The single-carrier laser output by the LD is input to the optical input port of the IM in the lower channel, and a single-tone signal with a frequency of f _d is input to the RF input port of the IM, and the DC bias of the IM is set to make the IM work at the minimum transmission point. The double sideband is filtered out by OBPF and output after the lower sideband is filtered to realize the frequency shift of a single carrier;

Step 7: The frequency-shifted optical carrier is input to the optical input port of the local oscillator optical comb generation module, first enters DPMZM3 to generate a 7-line optical comb, and then enters DPMZM4 to expand the 7-line optical comb to generate 49 lines. The local oscillator signal LO ₁ output by the oscillator signal source is input to the RF input port of DPMZM3. Similarly, the DC bias voltages V _3a , V _3b and V _3c in DPMZM3 are set. The output of DPMZM3 is 7 after the frequency shift f _d Linear LO comb;

DPMZM4输出一个移频f_d的49线本振光梳；Step 8: The 7-line optical local oscillator output by DPMZM3 enters the optical input port of DPMZM4. Similarly, set the values of DC bias voltages V _4a , V _4b and V _4c in DPMZM4, then each fundamental vibration comb output by DPMZM3 is used as The new optical carrier is again modulated to produce a 7-line optical local oscillator. Similarly, the frequency value of the input local oscillator signal LO2 is the same as that of LO1.

DPMZM4 outputs a 49-line LO comb with shifted frequency f _d ;

Step 9: Each LO comb output by DMZM4 is divided into independent sub-channels after entering WDM2;

Step 10: Each independent sub-channel segmented by WDM1 and the corresponding independent sub-channel segmented by WDM2 are respectively used as two-way inputs to enter the OHC for down-conversion;

Step 11: The same-IF signal obtained after down-conversion enters the BPD to realize balanced detection.

Step 12: After the balance detection, the IQ baseband signal is obtained and input to the ADC for final digital processing.

The beneficial effect of the present invention is that the present invention can obtain an ideal 7-line optical comb by simply setting the three DC bias voltages in the DPMZM, and then easily complete the number of comb teeth of the optical frequency comb by means of double-drive cascade. times, to achieve the purpose of multi-channel expansion of the channelized receiver. In addition, through reasonable frequency shifting of the local oscillator optical comb, it can become the same intermediate frequency when each independent channel is down-converted, which greatly simplifies the complexity of the subsequent ADC and effectively simplifies the channelized receiver system.

Description of drawings

FIG. 1 is a diagram of an ultra-wideband radio frequency channelized receiving device with multi-channel expansion according to the present invention.

Figure 2 is a 7-line flat optical comb diagram generated by the DPMZM of the present invention.

FIG. 3 is a diagram of an intermediate frequency signal obtained after down-conversion in the present invention.

Figure 4 is a constellation diagram of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The system of the invention utilizes the reasonable setting of each DC bias voltage of the DPMZM, and can generate an ideal optical frequency comb with a large number of comb teeth and high flatness as a signal optical comb and a local oscillator optical comb, and realizes the multi-channel expansion of the channelized receiver. Reasonable frequency shifting of the local oscillator optical comb makes each channel after down-conversion be the same intermediate frequency signal and then enter the ADC for digital processing. By using the VPI optical simulation software, the proposed system is simulated and verified. The optical frequency comb generated by the experimental results has a high flatness and an out-band rejection ratio of 19.7dB.

The technical scheme adopted by the present invention to solve its technical problems is:

A multi-channel extended ultra-wideband radio frequency channelized receiving device includes a laser diode (LD), a dual-parallel Mach-Zehnder Modulator (DPMZM), a radio frequency signal source (RF), a local oscillator signal source ( LO), Intensity Modulator (IM), Optical Band Pass Filter (OBPF), Horse Boost Modulator (MZM), Wavelength Division Multiplexer (WDM), Optical Quadrature Coupler (OHC) and Balanced Detector (BPD) ); the LD output power is divided into upper and lower paths, the upper path is connected to the input end of the signal optical comb generation module, and the output end of the signal optical comb generation module is connected to the input end of the MZM; the broadband radio frequency signal RF3 is loaded on the radio frequency input end of the MZM , the output end of MZM is connected with the input end of WDM1, and the output end of WDM1 is divided into multiple channels; The vibrating optical comb generation module is connected, the output end of the local oscillator optical comb generation module is connected to the input end of WDM2, the output end of WDM2 is divided into multiple channels, and each branch of the output end of WDM2 corresponds to each branch of the output end of WDM1 one-to-one Then enter different OHCs as input signals, that is, WDM1 and WDM2 divide the received 49 optical combs into 49 independent frequency channels according to the frequency interval, the first channel in WDM1 and the first channel in WDM2 are combined after As an input signal into the OHC, the second channel in WDM1 and the second channel in WDM2 are combined once as another set of input signals into another OHC, and so on, the output of the OHC is connected to two BPDs, one BPD The I channel signal is demodulated, the other BPD demodulates the Q channel signal, and the output end of the BPD is connected to the ADC.

In the signal comb generation module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected to the RF signal source, the other RF input port MZMb is empty; the RF input end MZMa of DPMZM1 is connected to the RF signal RF1, the RF input end MZMa of DPMZM2 is connected to the RF signal RF2, and the output end of DPMZM1 is connected to the input of DPMZM2 The output end of DPMZM2 is connected with the input end of MZM;

In the local oscillator optical comb module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected with the RF signal source, and the other RF input port MZMb is unloaded; the local oscillator signal LO ₁ is connected with the RF input end MZMa in DPMZM3, the RF input end in DPMZM4 is connected with the local oscillator signal LO ₂ , and the output of DPMZM3 The terminal is connected with the input terminal of DPMZM4, and the output terminal of DPMZM4 is connected with the input terminal of WDM2.

The present invention comprises the following steps when working:

Step 1: The single-carrier laser output by the laser source is expressed as: E _in (t)=E ₀ exp(jω _c t), and the two radio frequency signals RF1 and RF2 generated by the radio frequency signal source are expressed as: s(t) ₁ = V ₁ sin(ω ₁ t), s(t) ₂ =V ₂ sin(ω ₂ t), where E ₀ is the electric field strength of the optical carrier, ω _c is the angular frequency of the optical carrier, s(t) ₁ and s(t) ₂ are two radio frequency signals, V ₁ and V ₂ are the amplitudes of the two radio frequency signals, respectively, and ω ₁ and ω ₂ are the angular frequencies of the two radio frequency signals respectively;

Step 2: The single-carrier laser output by the LD is input to the optical input port of the DPMZM1 on the upper channel, and the RF signal RF1 output by the RF signal source is input to the RF input port of the DPMZM1. The output of the DPMZM1 is expressed as:

Among them, A=πV _1a /2V _π , B=πV ₀ /2V _π , V _π represents the half-wave voltage of MZM or DPMZM, f represents the frequency of RF1, V ₀ is the voltage of the added RF signal RF1, and V _1a is the DPMZM1 The DC bias of the MZMa, V _1b is the DC bias of the MZMb of the DPMZM1, V _1c is the main DC bias of the DPMZM, J _n (x) represents the nth order Bessel function, when the

When , an ideal 7-line optical comb is obtained. By combining equations (1) and (2), the values of V _1a , V _1b , and V _1c when generating a 7-line optical comb are calculated;

否则会出现梳齿混叠影响宽带信号的调制效果，因此DPMZM2输出49线信号光梳；Step 3: The 7-line optical comb output by DPMZM1 enters the optical input port of DPMZM2, and the RF signal RF2 output from the RF signal source is input to the RF input port of DPMZM2. Similarly, set the DC bias voltages V _2a , V _2b , V in DPMZM2 The value of _2c , then each optical frequency comb output by DPMZM1 is used as a new optical carrier to be modulated into a 7-line optical comb again. At this time, the frequency value of the input RF signal RF2 is the size of RF1.

Otherwise, comb aliasing will affect the modulation effect of the broadband signal, so the DPMZM2 outputs a 49-line signal optical comb;

Step 4: The 49-line signal optical comb output by DPMZM2 enters the MZM. In the MZM, the broadband RF signal RF3 modulates the 49-line signal optical comb, and sets the DC bias of the MZM, so that the MZM works at the minimum transmission point, and performs bilateral carrier suppression. with modulation;

Step 5: Each modulated signal output by the MZM is divided into independent sub-channels after entering the WDM1;

Step 6: The single-carrier laser output by the LD is input to the optical input port of the IM in the lower channel, and a single-tone signal with a frequency of f _d is input to the RF input port of the IM, and the DC bias of the IM is set to make the IM work at the minimum transmission point. The double sideband is filtered out by OBPF and output after the lower sideband is filtered to realize the frequency shift of a single carrier;

Step 7: The frequency-shifted optical carrier is input to the optical input port of the local oscillator optical comb generation module, first enters DPMZM3 to generate a 7-line optical comb, and then enters DPMZM4 to expand the 7-line optical comb to generate 49 lines. The local oscillator signal LO ₁ output by the oscillator signal source is input to the RF input port of DPMZM3. Similarly, the DC bias voltages V _3a , V _3b and V _3c in DPMZM3 are set. The output of DPMZM3 is 7 after the frequency shift f _d Linear LO comb;

DPMZM4输出一个移频f_d的49线本振光梳；Step 8: The 7-line optical local oscillator output by DPMZM3 enters the optical input port of DPMZM4. Similarly, set the values of DC bias voltages V _4a , V _4b and V _4c in DPMZM4, then each fundamental vibration comb output by DPMZM3 is used as The new optical carrier is again modulated to produce a 7-line optical local oscillator. Similarly, the frequency value of the input local oscillator signal LO2 is the same as that of LO1.

DPMZM4 outputs a 49-line LO comb with shifted frequency f _d ;

Step 9: Each LO comb output by DMZM4 is divided into independent sub-channels after entering WDM2;

Step 10: Each independent sub-channel segmented by WDM1 and the corresponding independent sub-channel segmented by WDM2 are respectively used as two-way inputs to enter the OHC for down-conversion;

Step 11: The same-IF signal obtained after down-conversion enters the BPD to realize balanced detection.

Step 12: After the balance detection, the IQ baseband signal is obtained and input to the ADC for final digital processing.

In the present invention:

1) Laser: used to output single carrier laser;

2) RF signal source: used to generate RF carrier signal;

3) Optical fiber: as a transmission channel of optical signals, it is used for long-distance transmission of signals.

4) Parallel dual MZM booster: the two sub-MZMs work at a suitable operating point for electro-optical modulation of the RF drive signal;

5) Horse booster modulator: used for electro-optical modulation of the broadband radio frequency signal to be received.

6) Frequency-shifting module: It is composed of an intensity modulator and an optical band-pass filter, and is used to perform a reasonable frequency-shifting of the local oscillator optical comb.

7) Wavelength division multiplexer: used to independently divide the comb teeth of the optical frequency comb.

8) Photodetector: used for photoelectric conversion, converting optical signals into electrical signals.

9) Analog-to-digital converter: used to convert analog signals into digital signals.

Example:

The multi-channel extended ultra-wideband radio frequency channelized receiving device and method are simulated and verified by VPI optical simulation software. Refer to FIG. 1 for a device diagram of an embodiment.

The devices required in the experiment include: two RF signal sources RF1 and RF2, two local oscillator signal sources LO1 and LO2, arbitrary waveform generator, LD, DPMZM, MZM, IM, OBPF, OHC, WDM, BPD and ADC.

●Radio frequency signal RF1: frequency 40GHz, power 20dBm;

RF signal RF2: frequency 40/7GHz, power 20dBm;

Local oscillator signal LO1: frequency 39GHz, power 20dBm;

●Local oscillator signal LO2: frequency 39/7GHz, power 20dBm;

·Single carrier laser: output wavelength 1551nm, power 40mw;

●DPMZM: half-wave voltage 3.5V, insertion loss 15dB, extinction ratio 20dB;

●MZM: half-wave voltage 3.5V, insertion loss 15dB, extinction ratio 20dB;

IM: half-wave voltage 3.5V, insertion loss 20dB, extinction ratio 20dB;

WDM: frequency spacing 1GHz

·Photodetector: Responsivity 0.9A/W.

Steps:

Step 1: The light source generates a continuous light wave with an operating frequency of 193.1THz and a power of 20dBm. The continuous light wave is divided into two paths as the carrier power and then enters the add and drop paths respectively.

Step 2: Add the optical carrier to the DPMZM1, set the frequency of RF1 to 40GHz, and set the three DC bias voltages V _1a , V _1b , and V _1c of the DPMZM1 to output a flat 7-line optical comb, as shown in Figure 2.

Step 3: The frequency of RF2 is 40/7GHz, and the three DC bias voltages V _2a , V _2b and V _2c of DPMZM2 are set to output a flat 49-line signal optical comb.

Step 4: The 49-line signal comb enters the MZM and is modulated by a 25-30GHz broadband RF signal RF3 spanning the K and Ka bands.

Step 5: The signal comb modulated by the broadband RF signal RF3 enters the WDM1 and is divided into 49 independent channels with a spacing of 1GHz

Step 6: The drop optical carrier is input to the IM, and is modulated by a single tone signal f _d with a frequency of 28 GHz in the IM. The IM works at the minimum operating point, and the generated double-sideband signal is filtered out by the OBPF to remove the lower-sideband.

Step 7: After the frequency-shifted optical carrier is filtered by OBPF to filter out the lower sideband, the remaining upper sideband information enters DPMZM3, set the frequency of LO1 to 39, and set the three DC bias voltages V _3a , V _3b and V _3c of DPMZM3 to make it Similarly, a flat 7-line optical comb is output.

Step 8: The frequency of RF2 is 39/7GHz, and the three DC bias voltages V _4a , V _4b and V _4c of DPMZM4 are set to output a flat 49-line LO comb.

Step 9: The 49-line LO comb output from the DPMZM4 enters the WDM2 and is split into 49 independent channels spaced 1GHz apart

Step 10: Each independent sub-channel divided by WDM1 and its corresponding independent sub-channel divided by WDM2 are input into OHC as two-way input for down-conversion.

Step 11: After down-conversion of the corresponding two channels, different sub-channels of the same intermediate frequency can be obtained, as shown in FIG. 3 .

Step 12: The signal output by each channel is sent to the ADC for electrical domain signal processing. As shown in the constellation diagram in FIG. 4, the demodulated baseband signal has no obvious distortion.

Claims (4)

1. A multi-channel extended ultra-wideband radio frequency channelized receiving device, comprising a laser diode, a parallel dual MR modulator, a radio frequency signal source, a local oscillator signal source, an intensity modulator, an optical bandpass filter, and a MR modulator , wavelength division multiplexer, optical quadrature coupler and balanced detector, characterized by: The output of the LD is divided into upper and lower circuits. The upper circuit is connected to the input end of the signal optical comb generation module, and the output end of the signal optical comb generation module is connected to the input end of the MZM; the broadband RF signal RF3 is loaded on the RF input end of the MZM, and the MZM The output end of LD is connected with the input end of WDM1, and the output end of WDM1 is divided into multiple channels; The comb generation module is connected, the output end of the local oscillator optical comb generation module is connected with the input end of WDM2, the output end of WDM2 is divided into multiple channels, and each branch of the output end of WDM2 is in one-to-one correspondence with each branch of the output end of WDM1. Enter different OHCs as input signals, that is, WDM1 and WDM2 divide the received 49 optical combs into 49 independent frequency channels according to frequency intervals, and the first channel in WDM1 and the first channel in WDM2 are combined as input The signal enters the OHC, the second channel in WDM1 and the second channel in WDM2 are combined at one time as another set of input signals into another OHC, and so on, the output of the OHC is connected to two BPDs, one BPD demodulates The I channel signal is output, the other BPD demodulates the Q channel signal, and the output end of the BPD is connected to the ADC. 2. the ultra-wideband radio frequency channelization receiving device of a kind of multi-channel expansion according to claim 1, is characterized in that: In the signal comb generation module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected to the RF signal source, the other RF input port MZMb is empty; the RF input end MZMa of DPMZM1 is connected to the RF signal RF1, the RF input end MZMa of DPMZM2 is connected to the RF signal RF2, and the output end of DPMZM1 is connected to the input of DPMZM2 The output end of DPMZM2 is connected with the input end of MZM. 3. the ultra-wideband radio frequency channelization receiving device of a kind of multi-channel expansion according to claim 1, is characterized in that: In the local oscillator optical comb module, two DPMZMs are cascaded, namely DPMZM1 and DPMZM2, each DPMZM is composed of two parallel MZMa and MZMb and an independent DC bias voltage Vc, and each DPMZM has only one radio frequency The input port MZMa is connected with the RF signal source, and the other RF input port MZMb is unloaded; the local oscillator signal LO ₁ is connected with the RF input end MZMa in DPMZM3, the RF input end in DPMZM4 is connected with the local oscillator signal LO ₂ , and the output of DPMZM3 The terminal is connected with the input terminal of DPMZM4, and the output terminal of DPMZM4 is connected with the input terminal of WDM2. 4. a kind of method utilizing the ultra-wideband radio frequency channelization receiving device of a kind of multi-channel expansion described in claim 1, is characterized in that comprising the following steps: Step 1: The single-carrier laser output by the laser source is expressed as: E _in (t)=E ₀ exp(jω _c t), and the two radio frequency signals RF1 and RF2 generated by the radio frequency signal source are expressed as: s(t) ₁ = V ₁ sin(ω ₁ t), s(t) ₂ =V ₂ sin(ω ₂ t), where E ₀ is the electric field strength of the optical carrier, ω _c is the angular frequency of the optical carrier, s(t) ₁ and s(t) ₂ are two radio frequency signals, V ₁ and V ₂ are the amplitudes of the two radio frequency signals, respectively, and ω ₁ and ω ₂ are the angular frequencies of the two radio frequency signals respectively; Step 2: The single-carrier laser output by the LD is input to the optical input port of the DPMZM1 on the upper channel, and the RF signal RF1 output by the RF signal source is input to the RF input port of the DPMZM1. The output of the DPMZM1 is expressed as:

Among them, A=πV _1a /2V _π , B=πV ₀ /2V _π , V _π represents the half-wave voltage of MZM or DPMZM, f represents the frequency of RF1, V ₀ is the voltage of the added RF signal RF1, and V _1a is the DPMZM1 The DC bias of the MZMa, V _1b is the DC bias of the MZMb of the DPMZM1, V _1c is the main DC bias of the DPMZM, J _n (x) represents the nth order Bessel function, when the

To obtain an ideal 7-line optical comb, the equations (1) and (2) are simultaneously combined, and then the values of V _1a , V _1b , and V _1c are obtained when the 7-line optical comb is generated; Step 3: The 7-line optical comb output by DPMZM1 enters the optical input port of DPMZM2, and the RF signal RF2 output from the RF signal source is input to the RF input port of DPMZM2. Similarly, set the DC bias voltages V _2a , V _2b , V in DPMZM2 The value of _2c , then each optical frequency comb output by DPMZM1 is used as a new optical carrier to be modulated into a 7-line optical comb again. At this time, the frequency value of the input RF signal RF2 is the size of RF1.

Otherwise, comb aliasing will affect the modulation effect of the broadband signal, so the DPMZM2 outputs a 49-line signal optical comb; Step 4: The 49-line signal optical comb output by DPMZM2 enters the MZM. In the MZM, the broadband RF signal RF3 modulates the 49-line signal optical comb, and sets the DC bias of the MZM, so that the MZM works at the minimum transmission point, and performs bilateral carrier suppression. with modulation; Step 5: Each modulated signal output by the MZM is divided into independent sub-channels after entering the WDM1; Step 6: The single-carrier laser output by the LD is input to the optical input port of the IM in the lower channel, and a single-tone signal with a frequency of f _d is input to the RF input port of the IM, and the DC bias of the IM is set to make the IM work at the minimum transmission point. The double sideband is filtered out by OBPF and output after the lower sideband is filtered to realize the frequency shift of a single carrier; Step 7: The frequency-shifted optical carrier is input to the optical input port of the local oscillator optical comb generation module, first enters DPMZM3 to generate a 7-line optical comb, and then enters DPMZM4 to expand the 7-line optical comb to generate 49 lines. The local oscillator signal LO ₁ output by the oscillator signal source is input to the RF input port of DPMZM3. Similarly, the DC bias voltages V _3a , V _3b and V _3c in DPMZM3 are set. The output of DPMZM3 is 7 after the frequency shift f _d Linear LO comb; Step 8: The 7-line optical local oscillator output by DPMZM3 enters the optical input port of DPMZM4. Similarly, set the values of DC bias voltages V _4a , V _4b and V _4c in DPMZM4, then each fundamental vibration comb output by DPMZM3 is used as The new optical carrier is again modulated to produce a 7-line optical local oscillator. Similarly, the frequency value of the input local oscillator signal LO2 is the same as that of LO1.

DPMZM4 outputs a 49-line LO comb with shifted frequency f _d ; Step 9: Each LO comb output by DMZM4 is divided into independent sub-channels after entering WDM2; Step 10: Each independent sub-channel segmented by WDM1 and the corresponding independent sub-channel segmented by WDM2 are respectively used as two-way inputs to enter the OHC for down-conversion; Step 11: The same-IF signal obtained after down-conversion enters the BPD to realize balanced detection; Step 12: After the balance detection, the IQ baseband signal is obtained and input to the ADC for final digital processing.

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