CN110380749A - Single-channel radio frequency anti-saturation device, method and system - Google Patents

Abstract

The application relates to a single-channel radio frequency anti-saturation device, a method and a system thereof. The device comprises: the optical-electrical conversion module is used for receiving a radio-frequency input signal and converting the radio-frequency input signal into an optical signal, the optical branching module is used for dividing the optical signal into a plurality of paths of synchronous optical signals, the optical fiber delay module is used for respectively carrying out multi-path transmission on the plurality of paths of synchronous optical signals to generate a plurality of paths of delay optical signals with different delays relative to the synchronous optical signals, the optical-electrical conversion module is used for converting the plurality of paths of delay optical signals into a plurality of paths of delay electrical signals, and the algorithm processing module is used for carrying out iterative calculation on the plurality of paths of delay electrical signals through a self-adaptive filtering algorithm to obtain an optimal weight value to weight the delay electrical signals. By adopting the method, the radio frequency single channel can resist saturation.

Description

Single-channel radio frequency anti-saturation device, method and system

technical field

The present application relates to the field of radio frequency technology, in particular to a single-channel radio frequency anti-saturation device, method and system.

Background technique

The current anti-saturation technology at the receiving end mainly implements anti-saturation through an automatic gain control circuit (Automatic Gain Control, AGC). Using the AGC to control the gain can maintain a low gain or large attenuation state, avoiding the saturation phenomenon of subsequent circuits due to strong interference. At present, this solution is widely used. However, although the anti-saturation scheme of AGC can ensure that the receiver does not appear to be saturated, it has the same degree of suppression effect on interference and useful signals, and the actual useful signals cannot be used because the gain is too small.

Contents of the invention

Based on this, it is necessary to address the above technical problems and provide a single-channel radio frequency anti-saturation device, method and system that can solve the problem of suppression of useful signals caused by anti-saturation interference in the prior art.

A single-channel radio frequency anti-saturation device, said device comprising:

An electro-optical conversion module, configured to receive a radio frequency input signal and convert the radio frequency input signal into an optical signal;

An optical splitting module, configured to split the optical signal into multiple synchronous optical signals;

An optical fiber delay module, configured to multiplex the multiple synchronous optical signals to generate multiple delayed optical signals with different time delays relative to the synchronous optical signals;

A photoelectric conversion module, configured to convert the multi-channel time-delayed optical signal into a multi-channel time-delayed electrical signal;

The algorithm processing module is used to iteratively calculate the multi-channel time-delayed electrical signals through an adaptive filtering algorithm, obtain an optimal weight value to weight the time-delayed electrical signals, and output radio frequency.

In one of the embodiments, it also includes: the electro-optic conversion module includes: a laser and an electro-optic modulator; a light source with a preset wavelength is generated by the laser, and the electro-optic modulator receives a radio frequency input signal, and according to the light source to the radio frequency Carrier modulation is performed on the input signal to generate the optical signal.

In one of the embodiments, it also includes: the optical fiber delay module includes a plurality of optical fibers of different lengths; the multiple synchronous optical signals are transmitted in the optical fibers of different lengths to generate Multi-channel time-delayed optical signals with different time delays.

In one of the embodiments, it further includes: the plurality of optical fibers with different lengths are all single-mode optical fibers.

In one of the embodiments, it also includes: the algorithm processing module includes: an amplitude-phase weighting unit and an algorithm unit; the amplitude-phase weighting adjusts the amplitude and phase of the multiple time-delayed electrical signals respectively to obtain multiple Algorithm input signal; input the multi-path algorithm input signal into the algorithm unit, and the algorithm unit iteratively calculates the input multi-path algorithm input signal through an adaptive filtering algorithm, and outputs the optimal value of the amplitude-phase weighting unit An optimal weight value; setting parameters of the amplitude-phase weighting unit through the optimal weight value.

In one of the embodiments, it further includes: the algorithm processing unit performs iterative calculation through a least mean square adaptive filtering algorithm.

In one of the embodiments, it further includes: the electro-optic conversion module, the optical splitting module, the fiber delay module and the photoelectric conversion module are realized by a fiber delay line.

In one of the embodiments, it further includes: a band-pass filter; the band-pass filter is used for band-pass filtering the input signal of the algorithm.

A single-channel radio frequency anti-saturation method, said method comprising:

Convert the RF input signal into multiple synchronous optical signals;

performing multiplex transmission on the multiple synchronous optical signals respectively to obtain multiple delayed optical signals having different time delays relative to the synchronous optical signals;

converting the time-delayed optical signal into a time-delayed electrical signal, inputting the multi-channel time-delayed electrical signal into a preset adaptive filtering algorithm for iterative calculation, and obtaining an optimal weight corresponding to the time-delayed electrical signal;

Weighting the time-delayed electrical signal according to the optimal weight value, and performing radio frequency output.

A single-channel radio frequency anti-saturation system comprising:

The input unit is used to convert the radio frequency input signal into multiple synchronous optical signals;

A delay generating unit, configured to multiplex the multiple synchronous optical signals respectively to obtain multiple delayed optical signals with different time delays relative to the synchronous optical signals;

an iterative unit, configured to convert the time-delayed optical signal into a time-delayed electrical signal, input the multi-channel time-delayed electrical signal into a preset adaptive filtering algorithm for iterative calculation, and obtain the maximum value corresponding to the time-delayed electrical signal Priority value;

The radio frequency unit is configured to weight the time-delayed electrical signal according to the optimal weight value, and perform radio frequency output.

The above-mentioned single-channel radio frequency anti-saturation device, method and system, at the transmitting end, convert the electrical signal into an optical signal, and divide the optical signal into multiple optical signals, and transmit them in different channels to generate The optical signal is then converted into an electrical signal, and the time delay is reflected in the phase of the electrical signal. Through the difference in phase, an adaptive filtering algorithm is used to adaptively calculate the optimal weight, and the optimal weight is used for the electrical signal. The signal is weighted. Since the input electrical signal is used as the reference signal during iteration, the gain of the high-power interference signal can be suppressed, and the distortion attenuation of the useful signal can be reduced, so that the system can be improved while achieving anti-saturation. signal-to-interference ratio.

Description of drawings

Fig. 1 is a schematic structural diagram of a single-channel radio frequency anti-saturation device in an embodiment;

Fig. 2 is a schematic structural diagram of a single-channel radio frequency anti-saturation device in another embodiment;

Fig. 3 is a schematic structural diagram of an algorithm processing module in an embodiment when processing;

Fig. 4 is a schematic flow chart of a single-channel radio frequency anti-saturation method in an embodiment;

Fig. 5 is the structural block diagram of single channel radio frequency anti-saturation system in an embodiment;

Detailed ways

In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the present application.

In one embodiment, as shown in Figure 1, a single-channel radio frequency anti-saturation device is provided, including the following parts:

The electro-optical conversion module 110 is configured to receive a radio frequency input signal and convert the radio frequency input signal into an optical signal. Since the transmitting end receives the wireless signal through the antenna and internally receives the wireless signal in the form of an electrical signal, the electrical-optical conversion module 110 may be used for electrical-optical conversion.

The optical splitting module 120 is configured to convert the optical signal into multiple synchronous optical signals. The synchronous optical signal means that the strength, frequency, and wavelength of each optical signal are equal. The reason why this embodiment converts the electrical signal into an optical signal for transmission is that the loss of the optical signal is small during transmission, and it is easy to cause delay. Time. It is worth noting that it is divided into several synchronous optical signals, which can be set according to requirements. The more synchronous optical signals are divided into, the stronger the anti-interference ability will be, which will also lead to a large amount of calculation and slower system response.

The optical fiber delay module 130 is configured to perform multiplex transmission on multiple channels of synchronous optical signals to generate multiple channels of time-delayed optical signals with different time delays relative to the synchronous optical signals. Synchronous optical signals can choose different media, such as twisted pair, coaxial cable, optical fiber, etc. By performing multiplex transmission, time-delayed optical signals with different time delays can be generated.

The photoelectric conversion module 140 is configured to convert multiple time-delayed optical signals into multiple time-delayed electrical signals. Converting optical signals into electrical signals facilitates the construction of mathematical expressions of signals, which in turn facilitates mathematical calculations.

The algorithm processing module 150 is configured to iteratively calculate the multi-channel time-delayed electrical signals through an adaptive filtering algorithm, obtain an optimal weight value to weight the time-delayed electrical signals, and output radio frequency. Adaptive filtering algorithm can choose LMS adaptive filtering algorithm, NLMS adaptive filtering algorithm and so on.

In the above-mentioned single-channel radio frequency anti-saturation device, at the transmitting end, by converting the electrical signal into an optical signal, and dividing the optical signal into multiple optical signals, and transmitting them in different channels, optical signals with different time delays are generated, Then it is converted into an electrical signal, and the delay is reflected in the phase of the electrical signal. Through the difference in phase, an adaptive filtering algorithm is used to adaptively calculate the optimal weight, and the optimal weight is used to weight the electrical signal. Since the input electrical signal is used as the reference signal during iteration, the gain of the high-power interference signal can be suppressed, and the distortion attenuation of the useful signal can be reduced, so that the signal-to-interference ratio of the system can be improved while achieving anti-saturation .

In one embodiment, the electro-optic conversion module includes: a laser and an electro-optic modulator, the laser generates a light source with a preset wavelength, the electro-optic modulator receives a radio frequency input signal, and performs carrier modulation on the radio frequency input signal according to the light source to generate an optical signal. This embodiment provides a specific implementation of a photoelectric conversion module, through the same light source, it can be ensured that the optical signal has a uniform wavelength when the carrier is modulated.

Specifically, the laser can choose a DFB butterfly laser, which has a rate of 10Gbps and produces a light source with a wavelength of 1550nm, and the electro-optic modulator can choose an OCLARO electro-optic modulator with a model number of F10.

In one of the embodiments, the optical fiber is selected as the transmission medium of the synchronous optical signal. Therefore, each synchronous optical signal is transmitted through optical fibers of different lengths. Since light is transmitted in the optical fiber in the form of refraction, it can be greatly Increase the distance of optical signal transmission, so that it is easier to achieve high latency.

Specifically, when there are only two synchronous optical signals, the optical fiber length of one of them is set to 0, that is, the synchronous optical signal is directly sent to the photoelectric conversion module, and the optical fiber length of the other is set to 4 meters, the 13.3 ns can be achieved. delay.

In yet another embodiment, all the above-mentioned optical fibers are single-mode optical fibers, so that single-channel radio frequency anti-saturation interference can be realized.

In a specific embodiment, as shown in FIG. 2 , a specific single-channel radio frequency anti-saturation device is provided. In FIG. Carrier modulation is performed on the radio frequency input signal to obtain an optical signal. The optical splitter module 120 can choose an optical splitter 121. The illustration takes a 1×2 optical splitter as an example, and an optical splitter of other specifications can also be selected. The optical transmission medium selects optical fiber, so the optical fiber delay module 130 includes two optical fibers of different lengths, namely optical fiber 131 and optical fiber 132, and the photoelectric conversion module 140 includes a photodetector 141 and a photodetector 142, and also includes an algorithm processing module 150 .

In one of the embodiments, since the optical fiber delay line has the advantages of large time-bandwidth product, high frequency, good linearity, small insertion loss, and no electromagnetic interference, and the optical fiber delay line can directly accept the radio frequency input signal, and the output has a time delay Therefore, the above-mentioned electro-optic conversion module, optical splitting module, fiber delay module and photoelectric conversion module can be realized through the fiber delay line.

In one embodiment, the algorithm processing module includes an amplitude-phase weighting module and an algorithm unit, wherein the amplitude-phase weighting adjusts the amplitude and phase of multiple time-delayed electrical signals to obtain multiple algorithm input signals. The multi-path algorithm input signal is input to the algorithm unit, and the algorithm unit performs iterative calculation on the input multi-path algorithm input signal through an adaptive filtering algorithm, and outputs the optimal weight value of the optimal amplitude-phase weighting unit. The parameters of the amplitude and phase weighting unit are set through optimal weights. In this embodiment, the input time-delayed electrical signal is weighted by using an optimal weight value, so as to achieve an anti-saturation effect.

Specifically, as shown in Figure 3, a schematic structural diagram of an adaptive filtering algorithm is provided, wherein the symbol W refers to an amplitude-phase weighting subunit in the amplitude-phase weighting unit, and the time-delay electrical signal input amplitude-phase weighting The sub-unit outputs a weighted signal, and the algorithm unit calculates the error value through an adaptive algorithm, and iterates until the iteration stops, and completes the weight update of the amplitude-phase weighted sub-unit to obtain the optimal weight.

In addition, X ₁ (n) refers to the radio frequency input signal, and the process of delaying the radio frequency input signal is shown in the above embodiment, and will not be repeated in the figure, but is represented by delay. In addition, there are n optical fibers in the figure, that is, the optical signal is divided into n channels of synchronous optical signals, and n amplitude-phase weighting subunits are also set up to perform amplitude-phase weighting processing on the n channels of synchronous optical signals respectively.

In one embodiment, the algorithm unit performs iterative calculation through a least mean square adaptive filtering algorithm. The least mean square adaptive filtering algorithm is also called LMS (Least Mean Square, least mean square) algorithm, and the processing process of the LMS algorithm is as follows:

Filter output: y(n)=w(n) x(n)

Error signal: e(n)=d(n)-y(n)

Weight coefficient update: w(n+1)=w(n)-2·μ·e(n)·x(n)

Among them, y(n) refers to the RF output signal, w(n) refers to the weight of the nth amplitude-phase weighting subunit, and w(n+1) refers to the n+1th amplitude-phase weighting subunit The weight of the unit means that although there are only n amplitude-phase weighting subunits in this embodiment, w(n+1) can select the first amplitude-phase weighting subunit according to the time sequence of the delay. μ refers to the global step size parameter. In order to achieve the convergence of the LMS algorithm, generally speaking, 0<μ<1/λmax, where λmax corresponds to the eigenvalue decomposition of the correlation matrix of the input delay electrical signal of the amplitude-phase weighted subunit The largest eigenvalue after . d(n) refers to the reference signal, and it can be known from FIG. 3 that d(n) represents the radio frequency input signal.

Through the above analysis, for example, if the iteration condition is satisfied at e(n), the weight coefficient is updated to w(n+1), and the first amplitude-phase weighting subunit is assigned according to w(n+1), so that The signal output by the first amplitude-phase weighting subunit is used as the radio frequency output signal.

It is worth noting that the weight of the amplitude-phase weighting subunit is an imaginary number, expressed as ww=|a|e ^jb , and assigning a value to the amplitude-phase weighting subunit is to update the values of a and b.

It is worth noting that the amplitude and phase weighting unit can be realized by programmable attenuator and programmable phase shifter in hardware, and the algorithm unit can be realized by writing the code of LMS algorithm in a microprocessor chip such as FPGA or DSP.

In another embodiment, for the single-channel radio frequency anti-saturation device of two fiber channels, only one kind of interference signal can be resisted, and by analogy, for the single-channel radio frequency anti-saturation device of n fiber channels, it can resist n-1 kinds of interference Signal.

In addition, when performing anti-interference processing, it is also necessary to match the number of interference signals with the number of channels. For example, for a two-channel fiber optic channel, only one fiber signal can be processed. Therefore, other interference signals need to be filtered out. To deal with an interference signal, the specific method is to set a band-pass filter, the center frequency of the band-pass filter is the same as the frequency of the useful signal, and then adjust the bandwidth so that only one interference signal exists in the bandwidth spectrum.

In this embodiment, if there are multiple channels, a wider bandwidth can be set when setting the bandwidth of the bandpass filter.

Based on the above single-channel radio frequency anti-saturation device, a single-channel radio frequency anti-saturation method is provided. The single-channel radio frequency anti-saturation device can be realized by simulation software in a computer, and each component in the single-channel radio frequency anti-saturation device is simulated in the simulation software. Then, the single-channel radio frequency anti-saturation method is realized through computer program control.

In one embodiment, as shown in FIG. 4 , a single-channel radio frequency anti-saturation method is provided. Taking the method running in a computer device as an example, the method includes the following steps:

Step 402, converting the radio frequency input signal into multiple synchronous optical signals.

In step 404, the multiple channels of synchronous optical signals are respectively multiplexed to obtain multiple channels of time-delayed optical signals with different time delays relative to the synchronous optical signals.

Step 406 converts the time-delayed optical signal into a time-delayed electrical signal, and inputs multiple channels of time-delayed electrical signals into a preset adaptive filtering algorithm for iterative calculation to obtain the optimal weight corresponding to the time-delayed electrical signal.

Step 408, weighting the time-delayed electrical signal according to the optimal weight value, and performing radio frequency output.

It is worth noting that the single-channel radio frequency anti-saturation method corresponds to the single-channel radio frequency anti-saturation device. When each module in the single-channel radio frequency anti-saturation device changes, the single-channel radio frequency anti-saturation method changes accordingly. The single-channel radio frequency anti-saturation method caused by the change of each module in the channel radio frequency anti-saturation device will not be repeated here.

It should be understood that although the various steps in the flow chart of FIG. 4 are displayed sequentially as indicated by the arrows, these steps are not necessarily executed sequentially in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least some of the steps in FIG. 4 may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but may be executed at different times. The execution of these sub-steps or stages The order is not necessarily performed sequentially, but may be performed alternately or alternately with at least a part of other steps or sub-steps or stages of other steps.

In one embodiment, as shown in FIG. 5 , a schematic structural diagram of a single-channel radio frequency anti-saturation system is provided, including: an input unit 502 , a delay generation unit 504 , an iteration unit 506 and a radio frequency unit 508 .

The input unit 502 is used to convert the radio frequency input signal into multiple synchronous optical signals;

A delay generating unit 504, configured to perform multiplex transmission on the multiple synchronous optical signals respectively, to obtain multiple delayed optical signals with different time delays relative to the synchronous optical signals;

The iteration unit 506 is configured to convert the time-delayed optical signal into a time-delayed electrical signal, input the multi-channel time-delayed electrical signal into a preset adaptive filtering algorithm for iterative calculation, and obtain the time-delayed electrical signal corresponding to optimal weight;

The radio frequency unit 508 is configured to weight the time-delayed electrical signal according to the optimal weight, and perform radio frequency output.

For specific limitations on the single-channel radio frequency anti-saturation system, refer to the above-mentioned limitations on the single-channel radio frequency anti-saturation method, which will not be repeated here. Each module in the above-mentioned single-channel radio frequency anti-saturation system can be fully or partially realized by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, and can also be stored in the memory of the computer device in the form of software, so that the processor can invoke and execute the corresponding operations of the above-mentioned modules.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented through computer programs to instruct related hardware, and the computer programs can be stored in a non-volatile computer-readable memory In the medium, when the computer program is executed, it may include the processes of the embodiments of the above-mentioned methods. Wherein, any references to memory, storage, database or other media used in the various embodiments provided in the present application may include non-volatile and/or volatile memory. Nonvolatile memory can include read only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Chain Synchlink DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

The technical features of the above embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be It is considered to be within the range described in this specification.

The above-mentioned embodiments only represent several implementation modes of the present application, and the description thereof is relatively specific and detailed, but it should not be construed as limiting the scope of the patent for the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of protection of the patent application should be based on the appended claims.

Claims (10)

1. A single channel radio frequency anti-saturation device, said device comprising: An electro-optical conversion module, configured to receive a radio frequency input signal and convert the radio frequency input signal into an optical signal; An optical splitting module, configured to split the optical signal into multiple synchronous optical signals; An optical fiber delay module, configured to multiplex the multiple synchronous optical signals to generate multiple delayed optical signals with different time delays relative to the synchronous optical signals; A photoelectric conversion module, configured to convert the multi-channel time-delayed optical signal into a multi-channel time-delayed electrical signal; The algorithm processing module is used to iteratively calculate the multi-channel time-delayed electrical signals through an adaptive filtering algorithm, obtain an optimal weight value to weight the time-delayed electrical signals, and output radio frequency. 2. The device according to claim 1, wherein the electro-optic conversion module comprises: a laser and an electro-optic modulator; The laser generates a light source with a preset wavelength, the electro-optical modulator receives a radio frequency input signal, and performs carrier modulation on the radio frequency input signal according to the light source to generate the optical signal. 3. The device according to claim 1, wherein the optical fiber delay module comprises a plurality of optical fibers of different lengths; The multiple channels of synchronous optical signals are transmitted in the optical fibers of different lengths to generate multiple channels of time-delayed optical signals with different time delays relative to the synchronous optical signals. 4. The device according to claim 3, wherein the plurality of optical fibers with different lengths are all single-mode optical fibers. 5. The device according to claim 1, wherein the algorithm processing module comprises: an amplitude-phase weighting unit and an algorithm unit; The amplitude-phase weighting adjusts the amplitude and phase of the multi-channel time-delayed electrical signals respectively to obtain multi-channel algorithm input signals; Inputting the multi-path algorithm input signal into the algorithm unit, the algorithm unit iteratively calculates the input multi-path algorithm input signal through an adaptive filtering algorithm, and outputs the optimal optimal weight value of the amplitude-phase weighting unit ; The parameters of the amplitude-phase weighting unit are set through the optimal weight value. 6. The device according to any one of claims 1 to 5, characterized in that, the algorithm processing unit performs iterative calculation through a least mean square adaptive filtering algorithm. 7. The device according to any one of claims 1 to 5, wherein the electro-optical conversion module, the optical branching module, the optical fiber delay module and the photoelectric conversion module are implemented by an optical fiber delay line . 8. The device according to claim 5, further comprising: a bandpass filter; The band-pass filter is used for band-pass filtering the input signal of the algorithm. 9. A single-channel radio frequency anti-saturation method, characterized in that the method comprises: Convert the RF input signal into multiple synchronous optical signals; performing multiplex transmission on the multiple synchronous optical signals respectively to obtain multiple delayed optical signals having different time delays relative to the synchronous optical signals; converting the time-delayed optical signal into a time-delayed electrical signal, inputting the multi-channel time-delayed electrical signal into a preset adaptive filtering algorithm for iterative calculation, and obtaining an optimal weight corresponding to the time-delayed electrical signal; Weighting the time-delayed electrical signal according to the optimal weight value, and performing radio frequency output. 10. A single-channel radio frequency anti-saturation system, characterized in that, comprising: The input unit is used to convert the radio frequency input signal into multiple synchronous optical signals; A delay generating unit, configured to multiplex the multiple synchronous optical signals respectively to obtain multiple delayed optical signals with different time delays relative to the synchronous optical signals; an iterative unit, configured to convert the time-delayed optical signal into a time-delayed electrical signal, input the multi-channel time-delayed electrical signal into a preset adaptive filtering algorithm for iterative calculation, and obtain the maximum value corresponding to the time-delayed electrical signal Priority value; The radio frequency unit is configured to weight the time-delayed electrical signal according to the optimal weight value, and perform radio frequency output.