A control method for preventing transmitted signals from interfering with local reception and an RDSS terminal

Abstract

The present invention discloses a control method and an RDSS terminal for preventing transmitted signals from interfering with local reception. The method includes: before the RDSS transmission channel is about to transmit a signal, sending an effective transmission enable signal to the AGC control loop, the carrier tracking loop, and the spreading code tracking loop of the RNSS reception channel, and these three loops receive signals in a manner that keeps the working parameters fixed; after the RDSS transmission channel completes signal transmission, sending an invalid transmission enable signal to these three loops, and these three loops resume receiving signals in a manner of dynamically adjusting the working parameters. Without adding hardware circuits, this method ensures that when a low-cost RDSS terminal with insufficient transceiver isolation transmits a signal, the three loops of the RNSS reception channel will not be locked due to interference, and the receiving part can immediately work properly after the signal transmission is completed.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular, to a control method and an RDSS terminal for preventing transmitted signals from interfering with local reception. Background Art

[0002] An RDSS (Radio Determination Satellite Service) terminal refers to a satellite radio determination service terminal, which belongs to an active satellite positioning terminal. This terminal can transmit wireless signals to a satellite and receive wireless signals sent from the satellite.

[0003] Inside an RDSS terminal, there are two parts of circuits, namely a transceiver part and a receiver part. When the RDSS terminal transmits a signal, usually its receiving circuit is also working simultaneously. This will cause interference of the transmitted signal to the receiving circuit, resulting in the AGC control loop, DLL code tracking loop, and carrier loop in the receiving part losing lock due to the interference of the transmitted signal. After the transmitted signal is completed, the AGC control loop, DLL code tracking loop, and carrier loop in the receiving part need to re-capture and track, which takes a long time and affects the immediate normal operation of the receiving part. Summary of the Invention

[0004] The main technical problem to be solved by the present invention is to provide a control method and an RDSS terminal for preventing transmitted signals from interfering with local reception, and to solve the problem that it takes a long time for the receiving part to resume normal operation after the transmitted signal interferes with the receiving part in the prior art.

[0005] To solve the above technical problem, a technical solution adopted by the present invention is to provide a control method for preventing transmitted signals from interfering with local reception. The method includes two independently operating RDSS transmission channels and an RNSS reception channel. The RNSS reception channel maintains a receiving state, and the method includes the steps of:

[0006] Before the RDSS transmission channel is about to transmit a signal, it sends a valid transmission enable signal to the AGC control loop, carrier tracking loop, and spreading code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spreading code tracking loop receive signals in a manner that keeps the working parameters fixed.

[0007] After the RDSS transmission channel completes signal transmission, it sends an invalid transmission enable signal to the AGC control loop, carrier tracking loop, and spreading code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spreading code tracking loop resume receiving signals in a manner of dynamically adjusting the working parameters.

[0008] Preferably, after the AGC control loop receives the valid transmission enable signal, it keeps the amplification gain value fixed; after the AGC control loop receives the invalid transmission enable signal, it restores the amplification gain value to the dynamic adjustment value for the normal operation of the AGC control loop.

[0009] Preferably, after the carrier tracking loop receives the valid transmission enable signal, it keeps the frequency control value fixed; after the carrier tracking loop receives the invalid transmission enable signal, it restores the frequency control value to the dynamic adjustment value for the normal operation of the carrier tracking loop.

[0010] Preferably, after the spread spectrum code tracking loop receives the valid transmission enable signal, it keeps the code rate control value fixed; after the spread spectrum code tracking loop receives the invalid transmission enable signal, it restores the code rate control value to the dynamic adjustment value for the normal operation of the spread spectrum code tracking loop.

[0011] Preferably, the RDSS transmission channel includes a power amplifier module for power-amplifying the transmission signal. When the power amplifier module receives the valid transmission enable signal, it performs power amplification work; when it receives the invalid transmission enable signal, it stops power amplification work.

[0012] Based on the same concept, there is also provided an RDSS terminal for preventing interference of the transmitted signal with local reception, including two independently operating RDSS transmission channels and RNSS reception channels;

[0013] The RNSS reception channel includes an AGC control loop, a carrier tracking loop, and a spread spectrum code tracking loop, all of which include a transmission enable terminal for receiving a transmission enable signal;

[0014] When receiving the valid transmission enable signal, the AGC control loop, the carrier tracking loop, and the spread spectrum code tracking loop perform reception in a manner of keeping the current operating parameters fixed;

[0015] When receiving the invalid transmission enable signal, the AGC control loop, the carrier tracking loop, and the spread spectrum code tracking loop resume reception in a manner of dynamically adjusting the operating parameters.

[0016] Preferably, the RDSS transmission channel includes a power amplifier module for power-amplifying the RDSS transmission signal. The power amplifier module includes a transmission control terminal for receiving the transmission enable signal; when it receives the valid transmission enable signal, it performs power amplification work; when it receives the invalid transmission enable signal, it stops power amplification work.

[0017] Preferably, the AGC control loop includes a controllable gain amplifier, a control voltage generator, a voltage comparator, a level detector, a low-pass filter, and a DC amplifier. The control voltage generator also receives the transmission enable signal;

[0018] When the transmission enable signal is invalid, the AGC control loop operates in the normal automatic gain operating state. The control voltage output by the control voltage generator is sent to the controllable gain amplifier. The gain value of the controllable gain amplifier is proportional to the control voltage and is used to perform gain control on the received signal. The corresponding output signal is fed back into the level detector to detect the operating level of the output signal. Then, the operating level is low-pass filtered by the low-pass filter to perform an averaging operation on the operating level and filter out the high-frequency components therein. Then, it is input into the DC amplifier for DC signal amplification to obtain a DC voltage signal, which is compared with a reference voltage in the voltage comparator. The generated output comparison result is given to the control voltage generator to correspondingly control the increase or decrease of the output voltage of the control voltage generator, so that the output signal remains stable;

[0019] When the transmission enable signal is valid, the control voltage generator outputs a fixed voltage value, and the gain value of the corresponding controllable gain amplifier remains fixed.

[0020] Preferably, the spread spectrum code tracking loop includes a code discriminator, a first loop filter, a code rate controller, a first accumulator, and a first look-up table. The code rate controller also receives the transmission enable signal;

[0021] When the transmission enable signal is invalid, the code discriminator inputs the received signal and the local pseudo-code output from the first look-up table, performs code phase discrimination on the pseudo-code in the received signal and the local pseudo-code, and after obtaining the code phase deviation result of these two pseudo-code sequences, filters the code phase deviation result through the first loop filter to obtain a code phase control signal, which is then input into the code rate controller to adjust and select the code rate control value, so as to select an appropriate code rate control value to enter the first accumulator for phase accumulation, adjust the code clock phase, and then the output code clock looks up the spread spectrum code in the first look-up table, and correspondingly outputs the spread spectrum code to the code discriminator;

[0022] When the transmission enable signal is valid, the code rate control value in the code rate controller remains unchanged, and the first accumulator performs phase accumulation with this fixed code rate control value. The code clock phase also remains unchanged correspondingly, and the output code clock looks up the spread spectrum code in the first look-up table and outputs it.

[0023] Preferably, the carrier tracking loop includes a carrier discriminator, a second loop filter, a frequency controller, a second accumulator, and a second look-up table, wherein the frequency controller also receives the transmission enable signal;

[0024] When the transmission enable signal is invalid, the carrier discriminator inputs the received signal and the local carrier received from the output of the second look-up table, performs carrier phase discrimination on the carrier in the received signal and the local carrier, obtains the phase deviation result of these two carriers, filters the phase deviation result through the second loop filter to obtain a carrier phase control signal, and then inputs it to the frequency controller to adjust and select the frequency control value, so as to select an appropriate frequency control value to enter the second accumulator for phase accumulation, adjust the carrier phase, and then the output carrier phase looks up the carrier amplitude in the second look-up table, and correspondingly outputs the local carrier to the carrier discriminator;

[0025] When the transmission enable signal is valid, the frequency control value in the frequency controller remains unchanged, and the second accumulator performs phase accumulation with this fixed frequency control value, and the corresponding output carrier phase looks up the local carrier amplitude in the second look-up table and outputs it.

[0026] The beneficial effects of the present invention are as follows: The present invention discloses a control method and an RDSS terminal for preventing transmitted signals from interfering with local reception. The method includes: when the RDSS transmission channel is about to transmit a signal, it sends a valid transmission enable signal to the AGC control loop, the carrier tracking loop, and the spreading code tracking loop of the RNSS reception channel, and these three loops receive in a manner that keeps the working parameters fixed; after the RDSS transmission channel completes signal transmission, it sends an invalid transmission enable signal to these three loops, and these three loops resume receiving in a manner of dynamically adjusting the working parameters. Without adding hardware circuits, this method ensures that when a low-cost RDSS terminal with insufficient transceiver isolation transmits a signal, the three loops of the RNSS reception channel will not be interfered and lose lock, and the receiving part can work normally immediately after the transmission signal is completed. Description of the Drawings

[0027] Figure 1 is a flowchart of an embodiment of the control method for preventing transmitted signals from interfering with local reception according to the present invention;

[0028] Figure 2 is a schematic diagram of the composition of an embodiment of an RDSS terminal for preventing transmitted signals from interfering with local reception according to the present invention;

[0029] Figure 3 is a schematic diagram of the composition of an embodiment of the AGC control loop in an RDSS terminal for preventing transmitted signals from interfering with local reception according to the present invention;

[0030] Figure 4 It is the schematic diagram of the composition of an embodiment of the spread spectrum code tracking loop in the RDSS terminal for preventing transmitted signals from interfering with local reception according to the present invention;

[0031] Figure 5 The schematic diagram of the composition of an embodiment of the carrier tracking loop in the RDSS terminal for preventing transmitted signals from interfering with local reception according to the present invention. Detailed implementation manners

[0032] For the convenience of understanding the present invention, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present invention more thorough and comprehensive.

[0033] It should be noted that unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0034] Figure 1 It shows the flowchart of an embodiment of the control method for preventing transmitted signals from interfering with local reception. This method is mainly applied to the RDSS terminal, which includes two independently operating RDSS transmission channels and an RNSS reception channel. The RNSS reception channel remains in the receiving state, and further includes the steps:

[0035] S101: Before the RDSS transmission channel is about to transmit a signal, send a valid transmission enable signal to the AGC control loop, carrier tracking loop, and spread spectrum code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spread spectrum code tracking loop receive in a manner that keeps the working parameters fixed;

[0036] S102: After the RDSS transmission channel completes signal transmission, send an invalid transmission enable signal to the AGC control loop, carrier tracking loop, and spread spectrum code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spread spectrum code tracking loop resume receiving in a manner of dynamically adjusting the working parameters.

[0037] It can be seen that through the above steps, during the process of the RDSS transmitting channel sending a signal, after the three loops in the receiving channel receive a valid transmission enable signal, they receive in a manner where the current working parameters remain fixed, so that they will not be affected by the change of the received signal. That is to say, the interference fluctuation caused by the transmitted signal will not lead to the dynamic adjustment of the working parameters, thus maintaining the continuous working state of the loop during the process of the RDSS terminal sending a signal.

[0038] When the RDSS transmitting channel finishes sending a signal, it immediately switches to the normal receiving state. At this time, there is no interference caused by the transmitted signal. Therefore, it resumes receiving in a manner of dynamically adjusting the working parameters before, that is, dynamically adjusting the working parameters with the change of the normal received signal.

[0039] Therefore, this method is to output a valid transmission enable signal to the RNSS receiving channel while the RDSS terminal is sending a signal. After the RNSS receiving channel receives this valid enable signal, it "freezes" the corresponding parameters of the AGC control loop, the spreading code tracking loop, and the carrier tracking loop (that is, the loop continues to work but the corresponding parameters are no longer adjusted, and the corresponding parameters are: the amplification gain value of the AGC control loop, the code rate control value of the spreading code tracking loop, and the frequency control value of the carrier tracking loop). When the RDSS terminal finishes sending a signal, it outputs an invalid enable signal to the receiving part. After the RNSS receiving channel receives this signal, it immediately makes the AGC control loop, the spreading code tracking loop, and the carrier tracking loop work normally (the corresponding parameters are adjusted normally), so as to ensure that the RNSS receiving channel of the RDSS terminal can work normally immediately after the terminal finishes sending a signal.

[0040] It can be seen that this method, without adding hardware circuits, ensures that when a low-cost RDSS terminal with insufficient transceiver isolation sends a signal, the three loops of the RNSS receiving channel will not be locked due to interference, and the receiving part can work normally immediately after the signal is sent. It shortens the time for the low-cost RDSS terminal to lose lock of the receiving part loop due to interference from the transmitted signal, and then re-capture and track and then work normally from the receiving part loop.

[0041] Preferably, for the AGC control loop, in step S101, after the AGC control loop receives that the transmission enable signal is valid, it keeps the amplification gain value unchanged at the current value, that is, it amplifies the received signal with the current fixed gain value; in step S102, after the AGC control loop receives that the transmission enable signal is invalid, it restores the amplification gain value to the dynamic adjustment value when the AGC control loop works normally. The dynamic adjustment of this dynamic gain value depends on the detection of the power of the received signal. When the power of the received signal entering the AGC control loop becomes smaller, the corresponding dynamic gain value becomes larger; if the power of the received signal entering the AGC control loop becomes larger, the corresponding dynamic gain value becomes smaller. Thus, it is ensured that the signal power output by the AGC control loop remains stable.

[0042] Preferably, for the carrier tracking loop, in step S101, after the carrier tracking loop receives that the transmission enable signal is valid, it keeps the frequency control value unchanged at the current value, that is, the frequency output by the carrier tracking loop determined by this frequency control value remains unchanged; in step S102, after the carrier tracking loop receives that the transmission enable signal is invalid, it restores the frequency control value to the dynamic adjustment value when the carrier tracking loop works normally. The dynamic adjustment value when the carrier tracking loop works normally depends on the tracking of the carrier frequency of the received signal and changes with the change of the carrier frequency value, maintaining the same frequency as the carrier frequency or having the same frequency difference from the carrier frequency.

[0043] Preferably, for the RNSS receiving channel, the received signal is a direct sequence spread spectrum signal. For the spreading code tracking loop, in step S101, after the spreading code tracking loop receives that the transmission enable signal is valid, it keeps the code rate control value unchanged at the current value, that is, the code rate of the spreading code output by the spreading code tracking loop determined by this code rate control value remains unchanged; in step S102, after the spreading code tracking loop receives that the transmission enable signal is invalid, it restores the code rate control value to the dynamic adjustment value when the spreading code tracking loop works normally. The dynamic adjustment value when the spreading code tracking loop works normally depends on the tracking of the spreading code in the received signal and changes with the change of the code rate of the received spreading code, maintaining the same code rate as the received spreading code.

[0044] Preferably, the RDSS transmission channel includes a power amplifier module for power-amplifying the transmission signal. In step S101, when the power amplifier module receives that the transmission enable signal is valid, it performs power amplification work; in step S102, when the power amplifier module receives that the transmission enable signal is invalid, it stops power amplification work. In this way, both the energy consumption of the power amplifier module can be reduced and the interference to the normal reception of the receiving channel can be avoided.

[0045] Based on the same inventive concept, the present invention also provides an embodiment of an RDSS terminal for preventing transmitted signal interference with local reception, as Figure 2 shown, which includes two independently operating RDSS transmission channels and an RNSS reception channel; the RNSS reception channel includes an AGC control loop 201, a carrier tracking loop 203, and a spreading code tracking loop 202, all of which include a transmission enable terminal for receiving a transmission enable signal (including two states: valid or invalid), and the three are components of the RNSS demodulator 20. In front of the RNSS demodulator 20, there is a low-noise amplifier (LNA) 21 and a receiving antenna; when the received transmission enable signal is valid, the AGC control loop 201, the carrier tracking loop 203, and the spreading code tracking loop 202 receive in a manner that keeps the current operating parameters fixed; when the received transmission enable signal is invalid, the AGC control loop 201, the carrier tracking loop 203, and the spreading code tracking loop 202 resume receiving in a manner of dynamically adjusting the operating parameters.

[0046] The RDSS transmission channel includes a power amplifier module 11 for power-amplifying the RDSS transmission signal. The power amplifier module 11 includes a transmission control terminal 110 for receiving two control states of the transmission enable signal: valid or invalid; when the received transmission enable signal is valid, it performs power amplification work, and when the received transmission enable signal is invalid, it stops power amplification work. The RDSS transmission channel also includes an RDSS modulator 10 for generating the RDSS transmission signal. After being power-amplified by the power amplifier module 11, it is wirelessly transmitted through the transmission antenna.

[0047] Preferably, as Figure 3As shown, in the AGC control loop, it includes a controllable gain amplifier 2011, a control voltage generator 2012, a voltage comparator 2013, a level detector 2014, a low-pass filter 2015, and a DC amplifier 2016. The control voltage generator 2012 also receives a transmit enable signal. When the transmit enable signal is invalid, the AGC control loop operates in a normal automatic gain operating state. The control voltage output by the control voltage generator 2012 is sent to the controllable gain amplifier 2011. The gain value of the controllable gain amplifier 2011 is proportional to the control voltage and is used to control the gain of the received input signal. The corresponding output signal is output on the one hand and fed back into the level detector 2014 on the other hand to detect the operating level or output power of the received output signal. Then, the output operating level value is low-pass filtered by the low-pass filter 2015, which is equivalent to averaging the operating level and filtering out the high-frequency components therein. Then, it is input into the DC amplifier 2016 for DC signal amplification to obtain a DC voltage signal, which is compared with a reference voltage in the voltage comparator 2103. The generated comparison result is then given to the control voltage generator 2012 to correspondingly control the increase or decrease of the output voltage of the control voltage generator 2012, so as to keep the received output signal stable. When the transmit enable signal is valid, the control voltage generator outputs a fixed voltage value, and thus the gain value of the controllable gain amplifier is also fixed.

[0048] Preferably, since the received input signal that is interfered and enters during the RDSS signal transmission has stability, the fixed voltage value output by the control voltage generator can be preset according to the measured value of the received input signal of the receiving channel during the RDSS signal transmission, so as to keep the received output signal stable.

[0049] Preferably, as Figure 4As shown in the figure, in the spread spectrum code tracking loop, it includes a code discriminator 2021, a first loop filter 2022, a code rate controller 2023, a first accumulator 2024, and a first look-up table 2025. And the code rate controller 2023, the first accumulator 2024, and the first look-up table 2025 form a spread spectrum code NCO (Numerically Controlled Oscillator). Among them, the code rate controller 2023 also receives a transmission enable signal. The code discriminator 2021 inputs the received signal and the local pseudo-code output from the first look-up table 2025, performs code phase discrimination on the pseudo-code in the received signal and the local pseudo-code, and after obtaining the code phase deviation result of these two pseudo-code sequences, filters the code phase deviation result through the first loop filter 2022 to obtain a code phase control signal and then inputs it to the code rate controller 2023 to adjust and select the code rate control value, so as to select a suitable code rate control value to enter the first accumulator 2024 for phase accumulation, adjust the code clock phase, and then the output code clock looks up the spread spectrum code in the first look-up table 2025 and outputs the corresponding spread spectrum code to the code discriminator.

[0050] When the transmission enable signal is invalid, with the input of the received signal, code phase discrimination is performed on the pseudo-code in the received signal and the local pseudo-code, and the code phase of the local pseudo-code is dynamically adjusted so that it can track the change with the change of the pseudo-code phase in the received signal; when the transmission enable signal is valid, the code rate control value in the code rate controller 2023 will remain unchanged, so as to perform phase accumulation on the first accumulator 2024 with this fixed code rate control value, and the code clock phase also remains unchanged correspondingly, and the corresponding output code clock is used to look up and output the spread spectrum code in the first look-up table 2025.

[0051] Preferably, as Figure 5As shown in the figure, in the carrier tracking loop, it includes a carrier discriminator 2031, a second loop filter 2032, a frequency controller 2033, a second accumulator 2034, and a second look-up table 2035. And the frequency controller 2033, the second accumulator 2034, and the second look-up table 2035 form a carrier NCO (Numerically Controlled Oscillator). Among them, the frequency controller 2033 also receives a transmission enable signal. The carrier discriminator 2031 inputs the received signal and the local carrier received from the output of the second look-up table 2035, performs carrier phase discrimination on the carrier in the received signal and the local carrier, and after obtaining the carrier phase deviation result of these two carriers, filters the carrier phase deviation result through the second loop filter 2032 to obtain a carrier phase control signal and then inputs it to the frequency controller 2033 to adjust and select the frequency control value, so as to select an appropriate frequency control value to enter the second accumulator 2034 for phase accumulation, adjust the carrier phase, and then look up the carrier amplitude in the second look-up table 2035 for the output carrier phase, and correspondingly output the local carrier to the carrier discriminator.

[0052] When the transmission enable signal is invalid, with the input of the received signal, carrier discrimination is performed on the carrier in the received signal and the local carrier, and the phase of the local carrier is dynamically adjusted so that it can track the change with the change of the carrier phase in the received signal; when the transmission enable signal is valid, the frequency control value in the frequency controller 2033 will remain unchanged, so as to perform phase accumulation on the second accumulator 2034 with this fixed frequency control value, look up and output the local carrier amplitude in the second look-up table 2035 corresponding to the output carrier phase, and keep the local carrier phase unchanged.

[0053] It can be seen from this that the present invention discloses a control method and an RDSS terminal for preventing transmitted signals from interfering with local reception. The method includes: when the RDSS transmission channel is about to transmit a signal, it sends a valid transmission enable signal to the AGC control loop, the carrier tracking loop, and the spreading code tracking loop of the RNSS reception channel, and these three loops receive in a manner of keeping the working parameters fixed; after the RDSS transmission channel completes the signal transmission, it sends an invalid transmission enable signal to these three loops, and these three loops resume receiving in a manner of dynamically adjusting the working parameters. Without adding hardware circuits, this method ensures that when the low-cost RDSS terminal with insufficient transceiver isolation transmits a signal, the three loops of the RNSS reception channel will not be interfered and lose lock, and the receiving part can work normally immediately after the signal transmission is completed.

[0054] The above are only embodiments of the present invention, and do not thereby limit the patent scope of the present invention. Any equivalent structural transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present invention.

Claims

1. A control method for preventing transmitted signals from interfering with local reception, characterized in that, It includes two independently operating RDSS transmission channels and an RNSS reception channel. The RNSS reception channel remains in the receiving state, and the steps include: Before the RDSS transmission channel is about to send a signal, it sends an effective transmission enable signal to the AGC control loop, carrier tracking loop, and spreading code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spreading code tracking loop receive in a manner that keeps the working parameters fixed. After the RDSS transmission channel completes signal transmission, it sends an invalid transmission enable signal to the AGC control loop, carrier tracking loop, and spreading code tracking loop of the RNSS reception channel. The AGC control loop, carrier tracking loop, and spreading code tracking loop resume receiving in a manner of dynamically adjusting the working parameters.

2. The control method for preventing transmitted signal interference with local reception according to claim 1, wherein After the AGC control loop receives the effective transmission enable signal, it keeps the amplification gain value fixed. After the AGC control loop receives the invalid transmission enable signal, it resumes the amplification gain value to the dynamically adjusted value for the normal operation of the AGC control loop.

3. The control method for preventing transmitted signal interference with local reception according to claim 1, characterized in that, After the carrier tracking loop receives the effective transmission enable signal, it keeps the frequency control value fixed. After the carrier tracking loop receives the invalid transmission enable signal, it resumes the frequency control value to the dynamically adjusted value for the normal operation of the carrier tracking loop.

4. The control method for preventing transmitted signal interference with local reception according to claim 1, characterized in that, After the spreading code tracking loop receives the effective transmission enable signal, it keeps the code rate control value fixed. After the spreading code tracking loop receives the invalid transmission enable signal, it resumes the code rate control value to the dynamically adjusted value for the normal operation of the spreading code tracking loop.

5. The control method for preventing transmitted signal interference with local reception according to claim 1, characterized in that, The RDSS transmission channel includes a power amplifier module for power-amplifying the transmission signal. When the power amplifier module receives the effective transmission enable signal, it performs power amplification work. When it receives the invalid transmission enable signal, it stops power amplification work.

6. An RDSS terminal for preventing transmitted signals from interfering with local reception, characterized in that, It includes two independently operating RDSS transmission channels and an RNSS reception channel; The RNSS reception channel includes an AGC control loop, a carrier tracking loop, and a spreading code tracking loop. The AGC control loop, carrier tracking loop, and spreading code tracking loop all include transmission enable terminals for receiving transmission enable signals; Before the RDSS transmission channel is about to send a signal, the AGC control loop, carrier tracking loop, and spreading code tracking loop receive the effective transmission enable signal, and the AGC control loop, carrier tracking loop, and spreading code tracking loop receive in a manner that keeps the working parameters fixed. ​ 7. The RDSS terminal for preventing transmitted signal from interfering with local reception according to claim 6, wherein The RDSS transmission channel includes a power amplifier module for power-amplifying the RDSS transmission signal. The power amplifier module includes a transmission control terminal for receiving the transmission enable signal. When the received transmission enable signal is valid, it performs power amplification work. When the received transmission enable signal is invalid, it stops power amplification work.

8. The RDSS terminal for preventing transmitted signal from interfering with local reception according to claim 6, characterized in that The AGC control loop includes a controllable gain amplifier, a control voltage generator, a voltage comparator, a level detector, a low-pass filter, and a DC amplifier. The control voltage generator also receives the transmission enable signal. When the transmission enable signal is invalid, the AGC control loop operates in the normal automatic gain working state. The control voltage generator outputs a control voltage to the controllable gain amplifier. The gain value of the controllable gain amplifier is proportional to the control voltage and is used to perform gain control on the received signal. The corresponding output signal is fed back into the level detector to detect the working level of the output signal. Then, the working level is low-pass filtered through the low-pass filter to perform an average operation on the working level and filter out the high-frequency components therein. Then, it is input into the DC amplifier for DC signal amplification to obtain a DC voltage signal. The DC voltage signal is compared with a reference voltage in the voltage comparator, and the generated output comparison result is given to the control voltage generator to correspondingly control the increase or decrease of the output voltage of the control voltage generator, so that the output signal remains stable. When the transmission enable signal is valid, the control voltage generator outputs a fixed voltage value, and the gain value of the corresponding controllable gain amplifier remains fixed.

9. The RDSS terminal for preventing transmitted signal interference with local reception according to claim 6, wherein The spread spectrum code tracking loop includes a code discriminator, a first loop filter, a code rate controller, a first accumulator, and a first look-up table. The code rate controller also receives the transmission enable signal. When the transmission enable signal is invalid, the code discriminator inputs the received signal and the local pseudo-code output from the first look-up table, performs code phase discrimination on the pseudo-code in the received signal and the local pseudo-code, obtains the code phase deviation result of these two pseudo-code sequences, filters the code phase deviation result through the first loop filter to obtain a code phase control signal, and then inputs the code phase control signal into the code rate controller to adjust and select the code rate control value to select an appropriate code rate control value to enter the first accumulator for phase accumulation, adjusts the code clock phase, and then the output code clock is used to look up the spread spectrum code in the first look-up table, and correspondingly outputs the local pseudo-code to the code discriminator. When the transmission enable signal is valid, the code rate control value in the code rate controller remains unchanged, and the first accumulator performs phase accumulation with the fixed code rate control value, and the code clock phase also remains unchanged correspondingly. The corresponding output code clock is used to look up and output the spread spectrum code in the first look-up table.

10. The RDSS terminal for preventing transmitted signal interference with local reception according to claim 6, characterized in that, The carrier tracking loop includes a carrier discriminator, a second loop filter, a frequency controller, a second accumulator, and a second look-up table, wherein the frequency controller further receives the transmission enable signal; When the transmission enable signal is invalid, the carrier discriminator inputs the received signal and the local carrier received from the output of the second look-up table, performs carrier phase discrimination on the carrier in the received signal and the local carrier, obtains the phase deviation result of these two carriers, filters the phase deviation result through the second loop filter to obtain a carrier phase control signal, then inputs the carrier phase control signal into the frequency controller to adjust and select the frequency control value, so as to select an appropriate frequency control value to enter the second accumulator for phase accumulation, adjust the carrier phase, and then the output carrier phase is used to look up the carrier amplitude in the second look-up table, and correspondingly output the local carrier to the carrier discriminator; When the transmission enable signal is valid, the frequency control value in the frequency controller remains unchanged, and phase accumulation is performed on the second accumulator with the fixed frequency control value, and the correspondingly output carrier phase is used to look up and output the local carrier amplitude in the second look-up table.

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