Radio frequency channel control circuit and control method of repeater

Abstract

The invention relates to the technical field of repeater radio frequency channel control, and provides a repeater radio frequency channel control circuit and method, and the circuit comprises a radio frequency front-end circuit, the input end of which is connected with an output signal processing module of a repeater circuit, and the control end of which is connected with a processor; the antenna is used for receiving reflection signals and outputting emission and reflection signals; the input end of the feedback module circuit is connected with the output end of the radio frequency front-end circuit, and the feedback module circuit is used for separating the transmitted signal from the reflected signal to obtain a feedback signal and outputting the power of the reflected signal in the feedback signal to the processor; the first power meter is used for measuring the power of the transmitted signal and outputting to the processor; the processor calculates a voltage standing wave ratio according to the received emission signal power and reflection signal power; and executing radio frequency channel control logic according to the voltage standing wave ratio and the transmitting signal power. According to the invention, the standing wave detection period can be dynamically adjusted, false alarms and false turn-off are reduced, automatic recovery of the channel is realized, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of radio frequency channel control of a repeater, and in particular relates to a radio frequency channel control circuit and a control method of a repeater. Background Art

[0002] Repeaters are divided into digital fiber optic repeaters and digital wireless repeaters, and the coupling methods between repeaters and signal sources are divided into wired coupling and wireless coupling. Among them, digital fiber optic repeaters use wired coupling, and digital wireless repeaters use wireless coupling.

[0003] Digital fiber optic repeater Figure 1 As shown in the figure, it consists of a radio access unit (Master Unit, MU) and a remote unit (Remote Unit, RU). The radio access unit converts the downlink radio frequency signal of the new radio (New Radio, NR) source into a digital optical fiber repeater system through wired coupling, converts it into a digital signal, and then transmits it to the remote unit after photoelectric conversion into an optical signal. At the same time, the digital signal uploaded by the remote unit is converted into an uplink radio frequency signal and transmitted back to the source through a wired method. The radio access unit must support remote monitoring and management functions and centralized upgrade functions for its remote units. The remote unit converts the digital signal sent by the radio access unit into a radio frequency signal to achieve 5G wireless coverage; at the same time, the uplink radio frequency signal received wirelessly is converted into a digital signal and transmitted to the access unit.

[0004] Digital wireless repeater Figure 2 As shown, the downlink RF signal of the 5G signal source enters the digital wireless repeater through wireless coupling, converts it into a digital signal after low-noise amplification, performs digital processing, and then converts it into an RF signal after power amplification to achieve wireless coverage of the 5G signal; at the same time, the user signal enters the digital wireless repeater system through wireless reception, and after digital-to-analog conversion / digital processing / power amplification, it is transmitted back to the signal source wirelessly.

[0005] Standing waves refer to a distribution state formed along a transmission line by two waves with the same frequency and opposite transmission directions. One of the waves is generally a reflection of the other wave. Antinodes appear at the point where the voltage or current of the two waves is added, and nodes form at the point where the voltage or current of the two waves is subtracted. On the waveform, the position of the nodes and antinodes is always constant, giving the impression of "standing still", but its instantaneous value changes with time. If the amplitudes of the two waves are equal, the amplitude of the nodes is zero.

[0006] The full name of the standing wave ratio is voltage standing wave ratio (VSWR), also known as VSWR and SWR. It represents the ratio of the voltage at the antinode of the transmission line to the voltage at the valley, that is, VSWR = (Vmax / Vmin). It can also be expressed as VSWR = (1 + Γ) / (1 - Γ), where Γ is the reflection coefficient, a parameter that describes the degree of reflection of the electrical transmission line, and its value range is between -1 and 1. When the standing wave ratio is equal to 1, it means that the impedance of the feeder and the antenna is completely matched. At this time, all the high-frequency energy is radiated by the antenna, and there is no energy reflection loss; when the standing wave ratio is infinite, it means total reflection, and no energy is radiated at all.

[0007] In radio communications, the standing wave ratio is an important parameter to measure the performance of the antenna system. When the standing wave ratio is greater than 1, it means that part of the radio wave is reflected back and eventually turns into heat, causing the feeder to heat up. In practical applications, the standing wave ratio is usually required to be less than 2 to ensure the stability and reliability of transmission. If the standing wave ratio is too high, it may cause problems such as reduced signal quality and shortened communication distance. If the energy of the reflected radio wave is too large, a very high voltage is generated at the output port of the transmitter, which may even damage the transmitter.

[0008] In the indoor distributed system, in order to reduce costs, operators will consider using repeaters to replace signal sources in some low-capacity, low-value scenarios. When the repeater is connected to the indoor distributed system, if there is a fault in the antenna feed connection or the antenna feed itself, such as a disconnection or virtual connection between the antenna feed and the repeater, or a fault in the antenna feed system itself, a higher reflected power will be generated due to the mismatch of the antenna feed unit, resulting in a poor system standing wave ratio, which will deteriorate the signal transmission effect, reduce the channel gain of the repeater, and cause the downlink output power of the repeater to become lower and the uplink noise coefficient to increase. If part of the signal is reflected to the power amplifier and exceeds the maximum power of the power amplifier, it will cause the power amplifier to burn out, causing fatal damage to the equipment.

[0009] After receiving the signal from the donor base station, the repeater amplifies the signal through the power amplifier in the RF hardware, and then radiates the energy through the antenna at the output end. However, when the output end of the repeater is not connected to the antenna or is poorly matched with the antenna, the signal will be reflected back. When the reflected signal passes through the power amplifier, if the transmission signal power continues to exceed the power amplifier power requirement, it is easy to burn out the power amplifier and cause fatal damage to the repeater.

[0010] Therefore, in order to protect the repeater equipment, it is necessary to detect the VSWR of the repeater when it is working, and indicate whether to shut down the channel based on the detection results.

[0011] The detection process of a repeater is generally as follows: by setting a forward and reverse power detection unit between the duplexer and the antenna port of the repeater, the forward and reverse power detection is usually composed of a forward coupler and a reverse coupler. The forward coupling signal and the reverse coupling signal output from the forward coupler and the reverse coupler are attenuated to a certain value by an attenuator respectively, and the attenuated signal enters the corresponding detector for detection and is output as a voltage signal; the forward voltage and the reverse voltage are amplified by an operational amplifier and then enter the CPU for calculation. The CPU calculates the voltage standing wave ratio based on the forward voltage and the reverse voltage, and then compares the calculated voltage standing wave ratio with the standing wave alarm threshold value set by the system. If the actual voltage standing wave ratio is greater than the standing wave alarm threshold value, an alarm is generated; if it is less than or equal to the standing wave alarm threshold value, it is considered normal.

[0012] Once a standing wave alarm is detected in the repeater, the repeater will directly shut down the channel, such as closing the uplink and downlink, to prevent the RF power amplifier unit output port from being unloaded, resulting in infinite standing waves, thereby protecting the power amplifier module from damage.

[0013] The existing standing wave detection technology has the following problems: 1) Currently, when a repeater performs standing wave detection, if an abnormal standing wave is detected, the repeater will shut down the RF channel. When the standing wave returns to normal and the repeater channel needs to be opened, manual intervention is required on site to open the station again. Therefore, the existing solution for opening the station again is inefficient and will increase maintenance costs.

[0014] 2) When the output power of the repeater is low, that is, the useful signal is close to the noise floor, if it is interfered by external signals at this time, the reflected signal measured by the repeater may contain the external interference signal, affecting the accuracy of standing wave detection and increasing the probability of false alarms and false shutdowns. Summary of the invention

[0015] To solve the above problems, the present invention provides a radio frequency channel control circuit and control method for a repeater, which adopts a standing wave detection mechanism based on dynamic adjustment of the detection period of output power, combined with a multiple abnormal trigger shutdown strategy, to achieve automatic channel recovery and effectively reduce the false alarm rate and maintenance cost.

[0016] The following are the technical details of this disclosure: A radio frequency channel control circuit of a repeater, characterized by comprising: The RF front-end circuit has an input end connected to the output end of the output signal processing module of the repeater circuit, and a control end connected to the output end of the processor of the repeater circuit; after receiving the reflected signal, the transmitted signal and the reflected signal are output simultaneously; A feedback module circuit, whose input end is connected to the output end of the RF front-end circuit, is used to separate the transmission signal and the reflection signal to obtain a feedback signal, measure the reflection signal power in the feedback signal and output it to the processor of the repeater circuit; A first power meter, whose input end is connected to the output end of the RF front-end circuit, is used to measure the power of the transmitted signal and then output it to the processor of the repeater circuit; The processor of the repeater circuit is configured to: Control the RF front-end circuit to receive the reflected signal irregularly, and calculate the voltage standing wave ratio according to the received transmission signal power and the reflected signal power; If the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold, the number of standing wave anomalies is accumulated and recorded; if the number of standing wave anomalies reaches the third threshold, the RF channel of the repeater circuit is triggered to shut down, and after the shutdown, the number of standing wave anomalies is reset and the number of RF channel shutdowns is recorded; If the number of times the RF channel is shut down is less than the fourth threshold, wait for the first preset time and then reopen the channel for detection; if the number of times the RF channel is shut down is not less than the fourth threshold, reset the number of times the RF channel is shut down, open the RF channel after a second preset time and continue to detect standing waves; wherein the second preset time is greater than the first preset time.

[0017] Further, The processor of the repeater circuit is further configured to: When the voltage standing wave ratio is greater than the first threshold and the transmission signal power is less than the second threshold, a standing wave alarm is triggered; If the number of consecutive standing wave anomalies is less than the third threshold, a standing wave alarm is triggered each time.

[0018] Further, The feedback module circuit comprises: A coupler, whose input end is connected to the output end of the RF front-end circuit, is used to separate the transmission signal and the reflection signal output by the RF front-end circuit and output them; A first digital step attenuator, whose input end is connected to the output end of the coupler, and is used to adjust the power of the transmission signal and the reflection signal output by the coupler and then output; An analog-to-digital conversion circuit, whose input end is connected to the output end of the first digital step attenuator, is used for converting the analog signal into a digital signal and then outputting a feedback signal; The second power meter has an input end connected to the output end of the analog-to-digital conversion circuit and an output end connected to the input end of the processor, and is used to measure the power of the reflected signal in the feedback signal and then output it to the processor.

[0019] Further, The output signal processing module of the repeater circuit comprises: A digital pre-distortion processing module, whose input end is connected to the output end of the processor, is used to perform DPD operation on the digital signal output by the processor and then output it; A digital-to-analog conversion circuit is connected in series with the digital pre-distortion processing module and is used to convert the digital signal output by the digital pre-distortion processing module into an analog signal and then output it; A second digital step attenuator, whose input end is connected to the output end of the digital-to-analog conversion circuit, and whose output end is connected to the input end of the RF front-end circuit, is used to adjust the power of the signal before outputting it; The processor of the repeater circuit is further configured to: When the RF front-end circuit receives the reflected signal, freezing the DPD operation of the digital predistortion processing module; If the voltage standing wave ratio is normal, the RF front-end circuit is controlled not to receive the reflected signal, and the DPD operation of the digital pre-distortion processing module is started.

[0020] Further, The digital predistortion processing module comprises: A DPD pre-simulation module is used to pre-simulate the DPD operation and generate initial pre-distortion parameters; The DPD calibration module has an input end connected to the output end of the processor and the output end of the DPD pre-simulation module, and is used to compensate and output the signal output by the processor after adjusting the pre-distortion parameters.

[0021] Further, Also includes: A data acquisition module, whose input end is connected to the first power meter, the feedback module circuit and the output end of the DPD calibration module; used to obtain the transmission signal power, the feedback signal and the DPD calibration data generated by the DPD calibration module and transmit them to the processor; The processor corrects the interference on the transmit signal power caused by the abnormal DPD calibration by comparing the transmit signal power, the transmit signal in the feedback signal and the DPD calibration data, and obtains the corrected transmit signal power to calculate the voltage standing wave ratio.

[0022] Further, The voltage standing wave ratio is calculated as: VSWR=

[0023] Where VSWR is the voltage standing wave ratio, is the transmitted signal power, is the reflected signal power.

[0024] Further, The processor controls the radio frequency front-end circuit to receive the reflected signal irregularly through the GPIO control interface.

[0025] A control method for the radio frequency channel control circuit of the repeater, characterized by comprising: The processor is used to control the radio frequency front-end circuit to receive the reflected signal irregularly, and the voltage standing wave ratio is calculated according to the received transmission signal power and the reflected signal power; If the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold, the number of standing wave anomalies is accumulated and recorded; if the number of standing wave anomalies reaches the third threshold, the RF channel of the repeater circuit is triggered to shut down, and after the shutdown, the number of standing wave anomalies is reset and the number of RF channel shutdowns is recorded; If the number of times the RF channel is shut down is less than the fourth threshold, wait for the first preset time and then reopen the channel for detection; if the number of times the RF channel is shut down is not less than the fourth threshold, reset the number of times the RF channel is shut down, open the RF channel after a second preset time and continue to detect standing waves; wherein the second preset time is greater than the first preset time.

[0026] Further, The receiving time interval of the control RF front-end circuit to receive the reflected signal irregularly for: if , = ; if , = ; if , ; in, For a fixed time interval, is the minimum power threshold, is the maximum power threshold; , To adjust the parameters.

[0027] Compared with the prior art, the present invention has the following advantages: The radio frequency front-end circuit in the circuit disclosed in the present invention is used to output the transmission signal and the reflection signal at the same time after receiving the reflection signal irregularly; the first power meter is used to measure the transmission signal power of the repeater circuit and transmit it to the processor; the feedback module circuit is used to separate the transmission signal and the reflection signal output by the radio frequency front-end circuit to obtain the feedback signal, measure the reflection signal power in the feedback signal and output it to the processor of the repeater circuit; the processor calculates the voltage standing wave ratio according to the transmission signal power and the reflection signal power, and performs radio frequency channel control in combination with the transmission signal power; wherein: The processor controls the RF front-end circuit to perform irregular standing wave measurements, avoiding the blindness and resource waste of fixed-period measurements; The number of standing wave anomalies is accumulated and recorded only when the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold. This judgment method combined with the output power effectively avoids misjudgment caused by external interference. Because when the useful signal is close to the background noise and is interfered, if it is judged only based on the voltage standing wave ratio, false alarms and false shutdowns are prone to occur. In this method, when the standing wave is abnormal but the output power is low, only an alarm is triggered without accumulating the number of abnormalities. The RF channel is shut down only when the number of standing wave anomalies reaches the third threshold, preventing frequent shutdowns due to accidental factors. After shutdown, if the number of RF channel shutdowns is less than the fourth threshold, the channel will be reopened for detection after a certain period of time. If it is not less than the fourth threshold, the RF channel will be opened after a long interval and standing waves will continue to be detected. This automatic channel reopening mechanism solves the problem of manual intervention required for secondary station opening, low efficiency and high maintenance cost in the existing solution, realizes automatic recovery of the channel, greatly improves maintenance efficiency and reduces costs.

[0028] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. The purpose and other advantages of the present disclosure can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 The network diagram of digital optical fiber repeater is shown; Figure 2 The digital wireless repeater network diagram is shown; Figure 3 A schematic diagram of the circuit disclosed in the present invention is shown; Figure 4 A schematic diagram of the radio frequency channel control logic of the present disclosure is shown. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0032] The circuit disclosed in the present invention is Figure 3 As shown, including: 1) Processor of repeater circuit; 2) Output signal processing module, including: A digital predistortion (DPD) processing module, whose input end is connected to the output end of the processor, includes: a DPD pre-simulation module: used for pre-simulating the DPD operation and generating initial pre-distortion parameters; a digital pre-distortion calibration module, whose input end is connected to the processor and the output end of the DPD pre-simulation module, used for adjusting the pre-distortion parameters so that the signal achieves the best linearization effect, and then compensates the signal output by the processor and outputs it.

[0033] A digital-to-analog conversion (DAC) circuit, used for converting a digital signal output by the digital pre-distortion calibration module into an analog signal; The second digital step attenuator (DSA) is used to adjust the power of the analog signal and then output it.

[0034] 3) RF front-end circuit (Analog Front End, AFE), whose input end is connected to the output end of the output signal processing module of the repeater circuit, and whose control end is connected to the output end of the processor of the repeater circuit; including: A power amplifier (PA) is used to amplify and output the signal after the DSA adjusts the power; The switch module and the filter module have input ends connected to the output ends of the power amplifier PA; Among them, the switch module is used to realize dynamic switching of signal paths or working modes (such as standing wave detection and normal operation); The filter module is used to select the frequency of the radio frequency signal.

[0035] The RF front-end circuit is used to receive the reflected signal and output the transmitted signal and the reflected signal simultaneously.

[0036] 4) Antenna ANT, used to broadcast the signal output by the RF front-end circuit.

[0037] 5) A first power meter, whose input end is connected to the output end of the RF front-end circuit, is used to measure the power of the transmitted signal and then output it to the processor of the repeater circuit; 6) A feedback module circuit, whose input end is connected to the output end of the RF front-end circuit, includes: Coupler: It is located at the output end of the power amplifier and is used to separate the transmission signal and the reflected signal output by the RF front-end circuit and then output them; A first digital step attenuator DSA, whose input end is connected to the output end of the coupler, is used to adjust the power of the transmission signal and the reflection signal output by the coupler and then output; An analog-to-digital conversion circuit, whose input end is connected to the output end of the first digital step attenuator DSA, is used to convert the analog signal into a digital signal and then output a feedback signal; The second power meter has an input end connected to the output end of the analog-to-digital conversion circuit and an output end connected to the input end of the processor, and is used to measure the power of the reflected signal in the feedback signal and then output it to the processor.

[0038] 7) A data acquisition module, whose input end is connected to the first power meter, the feedback module circuit and the output end of the DPD calibration module; used to obtain the transmission signal power, the feedback signal and the DPD calibration data generated by the DPD calibration module and transmit them to the processor; The processor corrects the interference on the transmit signal power caused by abnormal DPD calibration by comparing the transmit signal power, the transmit signal in the feedback signal and the DPD calibration data, obtains the corrected transmit signal power to calculate the voltage standing wave ratio, and improves the accuracy of the standing wave calculation.

[0039] Specifically, the processor is configured with working mode coordination control (freeze DPD operation → switch detection mode → resume DPD operation), including: If the voltage standing wave ratio VSWR is normal during the standing wave detection period, the digital pre-distortion (DPD) processing module is started to work normally, and the RF front-end circuit AFE at this time changes to the normal DPD working mode (does not receive the reflected signal); When the processor actively triggers VSWR detection, the DPD operation is temporarily frozen and the GPIO interface is switched to VSWR working mode (achieved by the processor sending a control signal to the RF front-end circuit); after completing the VSWR measurement, the GPIO is switched to normal mode and the DPD operation is resumed; the processor actively reads the VSWR result and status.

[0040] Function: By measuring VSWR irregularly, the accuracy of VSWR measurement can be guaranteed, the normal operation of the DPD function of the repeater can be guaranteed, and the increase in power consumption caused by frequent detection can be avoided.

[0041] Specifically, the processor also dynamically adjusts the detection period T according to the output power: The present disclosure uses AFE (radio frequency front-end circuit) to perform VSWR detection on all transmission (TX) signals at irregular intervals, wherein the detection interval T is related to the repeater channel power P, and T satisfies the following formula requirements: The detection interval T is: if , = ; if , = ; if , ; in, For a fixed time interval, is the minimum power threshold, is the maximum power threshold; , To adjust the parameters.

[0042] Specific:

[0043] Where T is the detection interval, To set the cycle value, , To adjust the parameters, is the transmit signal power.

[0044] Specifically, the voltage standing wave ratio of the present disclosure is calculated as follows: VSWR=

[0045] Where VSWR is the voltage standing wave ratio, is the transmitted signal power, is the reflected signal power.

[0046] 2. The operating logic of the disclosed circuit to control the automatic opening and closing of the RF channel is as follows: Figure 4 As shown, including: Standing waves are detected irregularly. When standing wave anomalies are detected, the repeater processor determines whether there are standing wave anomalies based on the transmission power. When multiple patrol tests show standing wave anomalies, it proves that the standing wave detection is correct and the remote channel is closed at the same time. After the channel shutdown is triggered, when the number of shutdowns is less than the specified number, the channel will be automatically opened and standing wave detection will be performed after waiting for a certain period of time. The waiting time for each time is related to the number of shutdowns. If multiple patrol tests trigger channel shutdowns, the repeater will shut down the channel for a long time until the standing wave returns to normal, and then start the next round of standing wave detection.

[0047] The technical details are as follows: 1) The repeater starts to perform standing wave detection. The standing wave detection period T is determined according to the signal power P transmitted by the repeater; 2) When the standing wave value is greater than 3.5 and the transmit signal power is less than 27dBm, the standing wave alarm is triggered; 3) When the standing wave value is greater than 3.5 and the transmitting signal power is greater than 27dBm, the number of standing wave abnormalities is recorded; when the number of consecutive standing wave abnormalities is less than M times, the standing wave alarm is triggered each time.

[0048] 4) When the number of standing wave abnormalities is greater than or equal to M times, the channel shutdown is triggered. After the channel shutdown is triggered, the number of standing wave abnormalities is reset to zero, and the number of shutdowns is recorded; 5) When the number of shutdowns is less than N times, wait for m minutes and then reopen the channel to perform standing wave detection.

[0049] 6) When the cumulative trigger reaches N times, the channel shutdown alarm will be triggered, the shutdown times will be reset to zero, and the device will automatically open the channel after an interval of H hours, and then continue to perform standing wave detection normally.

[0050] For the nth detection, m satisfies the following formula requirements: m=

[0051] Among them, M, N, H, and t are determined according to the network indicator requirements. is the coefficient for controlling the waiting time.

[0052] In summary, the disclosed scheme proposes a new method for standing wave detection and automatic channel switching of a repeater. The repeater performs multiple polling detections on the standing wave. Each detection cycle is related to the power of the signal transmitted by the repeater. When multiple detections are abnormal and the output power is greater than the limit power each time, the RF channel will be closed. The channel will be automatically opened after being shut down for a certain period of time (the specific time is related to the number of shutdowns). When the channel is triggered to be shut down for multiple consecutive times, the channel will be automatically opened after waiting for a long time, and then the next round of standing wave detection will continue.

[0053] The disclosed solution has the following innovations: 1) The existing repeater detection scheme adopts a timing standing wave detection scheme, and does not consider the impact of the repeater output power on the detection interval. The present invention optimizes the detection interval based on the repeater output power, performs normal periodic detection of standing waves within a reasonable range of output power, and increases the detection frequency when the output power is too large or too small, thereby making the detection cycle more reasonable.

[0054] 2) When a repeater detects a standing wave anomaly, it usually shuts down the channel directly without considering the possibility of false alarms and shutdowns. The present disclosure optimizes the detection scheme, and the repeater will shut down the remote channel only when it detects a standing wave anomaly for multiple consecutive times, thereby reducing the probability of false alarms and shutdowns.

[0055] 3) After the channel of the repeater is closed, the channel will not be opened until the standing wave returns to normal, and manual intervention is required on site during the channel opening process. The present disclosure optimizes the shutdown time to make the shutdown time more reasonable, and when the shutdown time is reached, the repeater will automatically open the channel without manual intervention, thereby reducing maintenance costs.

[0056] Based on the circuit disclosed in the present invention, the present disclosure also provides a control method for the circuit, which includes: Using a processor to control a radio frequency front-end circuit to receive reflected signals irregularly; Calculating the voltage standing wave ratio according to the received transmission signal power and the reflected signal power; and freezing the DPD operation of the DPD processing module when the RF front-end circuit receives the reflected signal; If the voltage standing wave ratio is normal, the RF front-end circuit is controlled not to receive the reflected signal, and the DPD operation of the DPD processing module is started; If the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold, the number of standing wave anomalies is accumulated and recorded; if the number of standing wave anomalies reaches the third threshold, the RF channel of the repeater circuit is triggered to shut down, and after the shutdown, the number of standing wave anomalies is reset and the number of RF channel shutdowns is recorded; If the number of times the RF channel is shut down is less than the fourth threshold, wait for m minutes and then reopen the channel for detection; if the number of times the RF channel is shut down is not less than the fourth threshold, reset the number of times the RF channel is shut down, open the RF channel after an interval of H hours and continue to detect standing waves.

[0057] Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A radio frequency channel control circuit for a repeater, characterized in that: include: A radio frequency front-end circuit, whose input end is connected to the output end of the output signal processing module of the repeater circuit, and whose control end is connected to the output end of the processor of the repeater circuit; After receiving the reflected signal, the transmitted signal and the reflected signal are output simultaneously; A feedback module circuit, whose input end is connected to the output end of the RF front-end circuit, is used to separate the transmission signal and the reflection signal to obtain a feedback signal, measure the reflection signal power in the feedback signal and output it to the processor of the repeater circuit; A first power meter, whose input end is connected to the output end of the RF front-end circuit, is used to measure the power of the transmitted signal and then output it to the processor of the repeater circuit; The processor of the repeater circuit is configured to: Control the RF front-end circuit to receive the reflected signal irregularly, and calculate the voltage standing wave ratio according to the received transmission signal power and the reflected signal power; If the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold, the number of standing wave anomalies is accumulated and recorded; If the number of standing wave anomalies reaches the third threshold, the RF channel of the repeater circuit is triggered to shut down, after which the number of standing wave anomalies is reset and the number of RF channel shutdowns is recorded; If the number of times the RF channel is shut down is less than the fourth threshold, wait for the first preset time and then reopen the channel for detection; if the number of times the RF channel is shut down is not less than the fourth threshold, reset the number of times the RF channel is shut down, open the RF channel after a second preset time and continue to detect standing waves; wherein the second preset time is greater than the first preset time.

2. The radio frequency channel control circuit of a repeater according to claim 1, characterized in that: The processor of the repeater circuit is further configured to: When the voltage standing wave ratio is greater than the first threshold and the transmission signal power is less than the second threshold, a standing wave alarm is triggered; If the number of consecutive standing wave anomalies is less than the third threshold, a standing wave alarm is triggered each time.

3. The radio frequency channel control circuit of a repeater according to claim 1, characterized in that: The feedback module circuit comprises: A coupler, whose input end is connected to the output end of the RF front-end circuit, is used to separate the transmission signal and the reflection signal output by the RF front-end circuit and output them; A first digital step attenuator, whose input end is connected to the output end of the coupler, and is used to adjust the power of the transmission signal and the reflection signal output by the coupler and then output; An analog-to-digital conversion circuit, whose input end is connected to the output end of the first digital step attenuator, is used for converting the analog signal into a digital signal and then outputting a feedback signal; The second power meter has an input end connected to the output end of the analog-to-digital conversion circuit and an output end connected to the input end of the processor, and is used to measure the power of the reflected signal in the feedback signal and then output it to the processor.

4. The radio frequency channel control circuit of a repeater according to claim 1, characterized in that: The output signal processing module of the repeater circuit comprises: A digital pre-distortion processing module, whose input end is connected to the output end of the processor, is used to perform DPD operation on the digital signal output by the processor and then output it; A digital-to-analog conversion circuit is connected in series with the digital pre-distortion processing module and is used to convert the digital signal output by the digital pre-distortion processing module into an analog signal and then output it; A second digital step attenuator, whose input end is connected to the output end of the digital-to-analog conversion circuit, and whose output end is connected to the input end of the RF front-end circuit, is used to adjust the power of the signal before outputting it; The processor of the repeater circuit is further configured to: When the RF front-end circuit receives the reflected signal, freezing the DPD operation of the digital predistortion processing module; If the voltage standing wave ratio is normal, the RF front-end circuit is controlled not to receive the reflected signal, and the DPD operation of the digital pre-distortion processing module is started.

5. The radio frequency channel control circuit of a repeater according to claim 4, characterized in that: The digital predistortion processing module comprises: A DPD pre-simulation module is used to pre-simulate the DPD operation and generate initial pre-distortion parameters; The DPD calibration module has an input end connected to the output end of the processor and the output end of the DPD pre-simulation module, and is used to compensate and output the signal output by the processor after adjusting the pre-distortion parameters.

6. The radio frequency channel control circuit of a repeater according to claim 5, characterized in that: Also includes: A data acquisition module, whose input end is connected to the first power meter, the feedback module circuit and the output end of the DPD calibration module; Used to obtain the transmission signal power, feedback signal and DPD calibration data generated by the DPD calibration module and transmit them to the processor; The processor corrects the interference on the transmit signal power caused by the abnormal DPD calibration by comparing the transmit signal power, the transmit signal in the feedback signal and the DPD calibration data, and obtains the corrected transmit signal power to calculate the voltage standing wave ratio.

7. The radio frequency channel control circuit of a repeater according to claim 1, characterized in that: The voltage standing wave ratio is calculated as: VSWR= Where VSWR is the voltage standing wave ratio, is the transmitted signal power, is the reflected signal power.

8. The radio frequency channel control circuit of a repeater according to claim 1, characterized in that: The processor controls the radio frequency front-end circuit to receive the reflected signal irregularly through the GPIO control interface.

9. A control method for the radio frequency channel control circuit of the repeater according to claim 1, characterized in that: include: The processor is used to control the radio frequency front-end circuit to receive the reflected signal irregularly, and the voltage standing wave ratio is calculated according to the received transmission signal power and the reflected signal power; If the voltage standing wave ratio is greater than the first threshold and the transmission signal power is greater than the second threshold, the number of standing wave anomalies is accumulated and recorded; If the number of standing wave anomalies reaches the third threshold, the RF channel of the repeater circuit is triggered to shut down, after which the number of standing wave anomalies is reset and the number of RF channel shutdowns is recorded; If the number of times the RF channel is shut down is less than the fourth threshold, wait for the first preset time and then reopen the channel for detection; if the number of times the RF channel is shut down is not less than the fourth threshold, reset the number of times the RF channel is shut down, open the RF channel after a second preset time and continue to detect standing waves; wherein the second preset time is greater than the first preset time.

10. The control method according to claim 9, characterized in that: The receiving time interval of the control RF front-end circuit to receive the reflected signal irregularly for: if , = ; if , = ; if , ; in, For a fixed time interval, is the minimum power threshold, is the maximum power threshold; , To adjust the parameters.

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