Circuit structure and method for linearly adjusting output dynamic range

Abstract

The application relates to a circuit structure and a method for linearly adjusting the output dynamic range, and belongs to the technical field of electronic communication. The circuit structure comprises a first fixed-amplitude adjuster, an input end of which receives an input signal; a coupler, an input end of which is electrically connected with an output end of the first fixed-amplitude adjuster, and the coupling degree is not less than 10 dB; a controllable-amplitude adjuster, an input end of which is electrically connected with an output end of the coupler; a second fixed-amplitude adjuster, an input end of which is electrically connected with an output end of the controllable-amplitude adjuster, and an output end is used for outputting an adjusted output signal; a detector, an input end of which is electrically connected with an adjusting end of the coupler; and a voltage operator, an input end of which is electrically connected with an output end of the detector, and an output end is electrically connected with an adjusting end of the controllable-amplitude adjuster. The application has the beneficial effects of reducing the influence of the dynamic range of the adjusted output signal on the signal-to-noise ratio and meeting the high-frequency demand.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic communication, in particular to a circuit structure and method for linearly adjusting output dynamic range. BACKGROUND

[0002] In many wireless communication applications, the input signal range of the system varies with the working distance, and has a large dynamic range. Limited by the dynamic range of the analog-to-digital converter itself, a low-cost application cannot use an analog-to-digital converter (ADC) with too high a dynamic range, and thus the output dynamic range of the system needs to be reduced to the dynamic range of the analog-to-digital converter (ADC) to obtain the best working state. In addition, in some special wireless communication applications, the input signal range of the system varies little, and a large output signal dynamic range is required to provide sufficient detection and regulation accuracy for the input signal. In both cases, the dynamic range of the output signal needs to be adjusted, i.e., expanded or reduced.

[0003] The existing methods for expanding or reducing the output dynamic range rely on the nonlinear characteristics of components, such as the gain compression characteristics of amplifiers or mixers under large signals. When the components enter the saturation region, although the output dynamic range is reduced, the AM-AM distortion and AM-PM distortion caused by the saturation of the components reduce the signal-to-noise ratio of the output signal. The signal-to-noise ratio is an important indicator of signal quality, and the higher the signal-to-noise ratio, the higher the quality of the signal, and the lower the system transmission error rate.

[0004] Another commonly used AGC (automatic gain control) technology automatically adjusts the signals in the dynamic range to the same value, losing the monotonicity of the signals. Moreover, the AGC chip currently works below 500 MHz, and cannot meet the high-frequency demand. SUMMARY

[0005] In order to reduce the influence of adjusting the dynamic range of the output signal on the signal-to-noise ratio and meet the high-frequency demand, the present application provides a circuit structure and method for linearly adjusting the output dynamic range.

[0006] In a first aspect, the present application provides a circuit structure for linearly adjusting the output dynamic range, which adopts the following technical scheme:

[0007] The circuit structure for linearly adjusting the output dynamic range comprises:

[0008] A first fixed-amplitude adjuster, which receives an input signal at the input end;

[0009] A coupler, which is electrically connected to the output end of the first fixed-amplitude adjuster at the input end, and has a coupling degree of no less than 10 dB;

[0010] A controllable amplitude adjuster, an input end of which is electrically connected with the output end of the coupler;

[0011] A second fixed amplitude adjuster, an input end of which is electrically connected with the output end of the controllable amplitude adjuster, and an output end of which is used for outputting an adjusted output signal;

[0012] A detector, an input end of which is electrically connected with the adjusting end of the coupler;

[0013] A voltage operator, an input end of which is electrically connected with the output end of the detector, and an output end of which is electrically connected with the adjusting end of the controllable amplitude adjuster.

[0014] By adopting the technical scheme, the first fixed amplitude adjuster cooperates with the coupler, so that the signal range of the detector coupled thereto falls in the optimal interval of the dynamic range of the detector, the voltage operator generates a control signal according to the voltage amplitude output by the detector, the controllable amplitude adjuster increases or reduces the gain thereof according to the control signal, thereby expanding or reducing the dynamic range of the signal, and the second fixed amplitude adjuster is used for adjusting the output amplitude of the input signal to the required range; since the components in the main channel of the circuit structure are in a linear state during the working process, there are no nonlinear distortion and the like, thus effectively reducing the deterioration of the signal signal-to-noise ratio, and providing greater freedom for subsequent signal processing; and the circuit structure can be built by using appropriate chips in a frequency range as low as several MHz to Ka, and the frequency range for use is wide.

[0015] Optionally, the detector comprises an RMS detector, a logarithmic detector and a diode detector.

[0016] When the output dynamic range of the signal and the input signal dynamic range are linear in dB units, the detector is switched to the RMS detector or the logarithmic detector.

[0017] Optionally, the circuit structure for linearly adjusting the output dynamic range further comprises:

[0018] When the peak-to-average ratio of the input signal is greater than a set value, the detector is switched to the RMS detector.

[0019] When the peak-to-average ratio of the input signal is less than or equal to the set value, the detector is switched to the logarithmic detector.

[0020] By adopting the technical scheme, for a signal with a large peak-to-average ratio, the RMS detector can accurately measure the power of the signal and is not affected by the signal waveform and the change of the peak-to-average ratio; when the peak-to-average ratio of the input signal is small but the overall dynamic range is large, the logarithmic detector can convert the large range of input signal changes into a relatively small output change, which is convenient for measurement and processing.

[0021] Optionally, the first fixed amplitude adjuster and the second fixed amplitude adjuster each comprise a linear amplifier and a fixed attenuator.

[0022] When reducing the signal amplitude, the first fixed amplitude adjuster and / or the second fixed amplitude adjuster is switched to a fixed attenuator.

[0023] When increasing the signal amplitude, the first fixed amplitude adjuster and / or the second fixed amplitude adjuster is switched to a linear amplifier.

[0024] Optionally, the controllable amplitude adjuster comprises an attenuator and a controllable amplifier.

[0025] When expanding the dynamic range of the signal, the controllable amplitude adjuster is switched to a controllable amplifier.

[0026] When reducing the dynamic range of the signal, the controllable amplitude adjuster is switched to an attenuator, which is a digital attenuator or an electrically tunable attenuator.

[0027] Optionally, the circuit structure further comprises:

[0028] a dynamic response compensation module, an input end of which is electrically connected to an output end of the voltage operator, and an output end of which is electrically connected to an adjusting end of the controllable amplitude adjuster.

[0029] The dynamic response compensation module is configured to dynamically adjust the response time of the control signal according to the change rate of the input signal, comprising:

[0030] When the change rate of the input signal amplitude is higher than a preset threshold, the rising / falling time of the control signal is shortened to avoid signal overshoot or under-adjustment.

[0031] When the change rate of the input signal amplitude is lower than the preset threshold, the response time of the control signal is lengthened to reduce the interference of control noise on the signal.

[0032] By adopting the above technical solution, by introducing the dynamic response compensation module, the contradiction between "static precision" and "dynamic following speed" in the linear adjustment circuit is solved. For burst signals such as radar pulses and communication burst packets, fast response can avoid signal distortion during the adjustment process; for slowly changing signals such as environmental noise and smooth signals, slow response can suppress the noise introduced by the control link through filtering, further improving the signal-to-noise ratio. This design enables the circuit to maintain high-precision dynamic adjustment in complex signal scenarios, expanding its applicability in communication, radar and other fields with strict real-time requirements for signals.

[0033] Optionally, the circuit structure further comprises:

[0034] An adaptive threshold calibration module, the input end is respectively connected with the output end of the detector and the output end of the second fixed amplitude adjuster, and the output end is connected with the reference voltage end of the voltage operator;

[0035] The adaptive threshold calibration module is configured to:

[0036] Real-time monitoring of the deviation value of the actual dynamic range of the output signal and the target dynamic range;

[0037] According to the deviation value, the reference threshold of the voltage operator is dynamically adjusted.

[0038] By adopting the above technical scheme, the adjustment threshold of the circuit is usually a fixed value, which is easy to be affected by factors such as temperature drift, component aging, power supply fluctuation, etc., resulting in a decrease in dynamic range adjustment accuracy in long-term use. The adaptive threshold calibration module can correct the errors introduced by changes in the environment or device parameters in real time through the construction of an "output-feedback-calibration" closed loop, ensuring that the output dynamic range is always stable in the target interval. For example, when the temperature rises and the sensitivity of the detector decreases, the adaptive threshold calibration module will automatically increase the reference threshold to compensate for the detection deviation; when the attenuation amount of the second fixed amplitude adjuster drifts, the control logic of the voltage operator is corrected through the feedback voltage at the output end. This design significantly improves the environmental adaptability and long-term reliability of the circuit, and is especially suitable for scenarios such as satellite communication, avionics, etc. with long service life and high stability requirements.

[0039] In a second aspect, the application provides a method for linearly adjusting the output dynamic range, which adopts the following technical scheme:

[0040] A method for linearly adjusting the output dynamic range, comprising:

[0041] S1, input signal preprocessing and coupling sampling;

[0042] The first fixed amplitude adjuster receives the input signal and pre-adjusts the input signal according to the initial amplitude characteristics of the input signal, so that the signal enters the linear working interval of the main channel; the adjusted signal is transmitted to the coupler, and the coupler couples part of the signal energy to the detector with a coupling degree of not less than 10 dB, so as to ensure that the signal amplitude coupled to the detector falls within its optimal dynamic range interval, and the main channel signal continues to be transmitted to the controllable amplitude adjuster;

[0043] S2, signal amplitude detection and control signal generation;

[0044] The detector detects the amplitude of the sampled signal output by the coupler, and selects the type of detector according to the characteristics of the input signal: the detector outputs a direct current voltage signal related to the power or amplitude of the input signal, which is transmitted to the voltage operator. The voltage operator compares the voltage with the reference threshold to generate an initial control signal for adjusting the controllable amplitude adjuster;

[0045] S3, amplitude adjustment;

[0046] The controllable amplitude adjuster switches the working mode according to the control signal in combination with the demand of the system for the output dynamic range, so as to realize linear dynamic control of the amplitude of the main channel signal:

[0047] If the output dynamic range needs to be expanded, the gain is increased through the control signal; if the output dynamic range needs to be reduced, the attenuation amount is increased through the control signal;

[0048] S4, output amplitude calibration;

[0049] The signal output by the controllable amplitude adjuster is transmitted to the second fixed amplitude adjuster, and the second fixed amplitude adjuster adjusts the signal amplitude to the target range according to the final output amplitude requirement and outputs.

[0050] In summary, the present application has at least the following beneficial effects:

[0051] 1. High flexibility: the same circuit can both expand and reduce the output dynamic range.

[0052] 2. Simple structure and high reliability: the circuit structure is simplified, the connection relationship is simple, and the reliability is high.

[0053] 3. Control cost according to actual situation: according to the response speed requirement and the dynamic range control accuracy, different performance components can be selected to complete the system requirement, and the cost requirement can be flexibly responded.

[0054] 4. Small signal-to-noise ratio deterioration: the components on the signal main channel in the circuit all work in a linear working state, and the signal-to-noise ratio deterioration is small.

[0055] 5. Wide frequency range: from several MHz to Ka frequency band, appropriate chips can be found to build the circuit structure. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 is the first structural block diagram of the circuit embodiment of the present application;

[0057] Figure 2 is the second structural block diagram of the circuit embodiment of the present application;

[0058] Figure 3 is the simulation diagram of simulation verification 1 of the present application;

[0059] Figure 4 is the simulation diagram of simulation verification 2 of the present application;

[0060] Figure 5 is the flowchart of the method embodiment of the present application.

[0061] Explanation of reference signs: 1, first fixed amplitude adjuster; 2, coupler; 3, controllable amplitude adjuster; 4, second fixed amplitude adjuster; 5, detector; 6, voltage operator; 7, dynamic response compensation module; 8, adaptive threshold calibration module. DETAILED DESCRIPTION

[0062] To make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the following will combine the accompanying drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application. Figure 1 - accompanying drawings Figure 5 The technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are some, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0063] The first embodiment of the present application discloses a circuit structure for linearly adjusting output dynamic range. Referring to Figure 1 The circuit structure can include a first fixed amplitude adjuster 1, a coupler 2, a controllable amplitude adjuster 3, a second fixed amplitude adjuster 4, a detector 5 and a voltage operator 6.

[0064] The first fixed amplitude adjuster 1, the coupler 2, the controllable amplitude adjuster 3 and the second fixed amplitude adjuster 4 are connected in series as main channel components for input signal transmission.

[0065] The detector 5 and the voltage operator 6 are connected in series, the input end of the detector 5 is electrically connected with the adjusting end of the coupler 2, and the output end of the voltage operator 6 is electrically connected with the adjusting end of the controllable amplitude adjuster 3.

[0066] The first fixed amplitude adjuster 1 and the second fixed amplitude adjuster 4 both include a linear amplifier and a fixed attenuator. For example, the linear amplifier can use a 20dB gain amplifier SBB5089Z, a 13dB fixed amplifier ERA-1SM, etc., and the fixed attenuator can use a 10dB fixed attenuator BAT-10+, etc. When reducing the signal amplitude, the first fixed amplitude adjuster 1 and / or the second fixed amplitude adjuster 4 are switched to the fixed attenuator; when increasing the signal amplitude, the first fixed amplitude adjuster 1 and / or the second fixed amplitude adjuster 4 are switched to the linear amplifier.

[0067] The coupler 2 can be implemented by using a power divider or a coupler, for example, a 20dB coupling degree BDCN-20-13, a 20dB coupling degree BDCN-20-13, a 10dB coupling degree ADC-10-4+, etc. The coupling degree of the coupler 2 is not less than 10dB.

[0068] The controllable amplitude adjuster 3 includes an attenuator and a controllable amplifier. The attenuator can be a digital attenuator, such as PE43711, or an electric attenuator, such as ADH346S. When the dynamic range of the signal is to be expanded, the controllable amplitude adjuster 3 is switched to the controllable amplifier; when the dynamic range of the signal is to be reduced, the controllable amplitude adjuster 3 is switched to the attenuator.

[0069] The detector 5 includes an RMS detector 5, a logarithmic detector 5, and a diode detector 5. When the output dynamic range of the signal is required to be linear with the input signal dynamic range in dB, the detector 5 is switched to the RMS detector 5 or the logarithmic detector 5; otherwise, the diode detector 5 is selected. The diode detector 5 can be LT5535. In addition, when the peak-to-average ratio of the input signal is greater than a set value, the detector 5 is switched to the RMS detector 5, which can be LT5581; when the peak-to-average ratio of the input signal is less than or equal to the set value, the detector 5 is switched to the logarithmic detector 5, which can be LT5534.

[0070] The voltage operator 6 can generate a control signal through calculation according to the input voltage amplitude. The voltage operator 6 can adopt a structure of an operational amplifier, an analog-to-digital converter (ADC) plus a microcontroller (MCU) / processor (CPU), an analog-to-digital converter (ADC) plus a field programmable logic (FPGA), etc. For example, the operational amplifier can be AD826, the analog-to-digital converter can be MAX1182 with a sampling rate of 65Msps, the microcontroller / processor can be STM32F103C8T6, and the field programmable logic can be EP4CE10F17C8.

[0071] Further, with reference to Figure 2 The circuit structure can further include a dynamic response compensation module 7 and an adaptive threshold calibration module 8.

[0072] The dynamic response compensation module 7 is electrically connected to the output end of the voltage operator 6 and the adjustment end of the controllable amplitude adjuster 3. The adaptive threshold calibration module 8 is electrically connected to the output end of the detector 5 and the output end of the second fixed amplitude adjuster 4, and is electrically connected to the reference voltage end of the voltage operator 6.

[0073] The dynamic response compensation module 7 is configured to dynamically adjust the response time of the control signal according to the change rate of the input signal, including:

[0074] When the input signal amplitude change rate is higher than a preset threshold, the rise / fall time of the control signal is shortened to avoid signal overshoot or under-adjustment; when the input signal amplitude change rate is lower than the preset threshold, the response time of the control signal is extended to reduce the interference of control noise on the signal.

[0075] The dynamic response compensation module 7 core can be composed of a differential circuit combined with a hysteresis comparator. The input of the differential circuit is directly connected to the output of the voltage operator 6 to extract the change rate of the input signal in real time. The differential circuit can be a passive RC differential network or an active differential circuit built with a high-speed operational amplifier, which converts the amplitude change of the input signal into a voltage signal proportional to the change rate. This voltage signal is then sent to the hysteresis comparator, which compares it with the preset fast and slow threshold voltages. When the detected change rate voltage is higher than the fast threshold, the hysteresis comparator outputs a high-level control signal, triggering an acceleration adjustment unit composed of a MOS switch and an RC network. This unit shortens the rise / fall time of the control signal by reducing the equivalent capacitance value of the adjustable amplitude adjuster 3 adjustment end (for example, by switching a plurality of compensation capacitors in parallel to a state of partial access or no access), ensuring the circuit's immediate response to rapidly changing signals and avoiding overshoot or under-adjustment phenomena. Conversely, when the change rate voltage is lower than the slow threshold, the hysteresis comparator outputs a low level, and the acceleration adjustment unit does not work. The adjustable amplitude adjuster 3 adjustment end maintains a large equivalent capacitance, allowing the control signal to change at a slower rate and effectively smoothing noise interference. To further optimize dynamic performance, a monostable trigger can be added between the hysteresis comparator and the acceleration adjustment unit to set the duration of the acceleration adjustment and prevent frequent switching of the switch due to signal jitter.

[0076] The adaptive threshold calibration module 8 is configured to:

[0077] Monitor the deviation value of the actual dynamic range of the output signal from the target dynamic range in real time; dynamically adjust the reference threshold of the voltage operator 6 according to the deviation value.

[0078] The core design of the adaptive threshold calibration module 8 uses a precision subtractor circuit (using an INA128 instrumentation amplifier) to calculate the deviation value between the output of the detector 5 and the output of the second fixed amplitude adjuster 4. This deviation signal is directly input into an integral controller (composed of an operational amplifier such as OPA277, configured as an integrator mode). The integral controller dynamically generates a correction voltage based on the polarity and size of the deviation value: when the actual dynamic range is higher than the target, the integral controller outputs a negative slope, lowering the reference threshold of the voltage operator 6; conversely, it outputs a positive slope, increasing the reference threshold, thereby gradually eliminating the deviation and ensuring the system converges to the target dynamic range. To handle noise and transient interference, a clamping circuit (using a diode limiter such as 1N4148) can be added in front of the integral controller to limit the input range of the deviation value, and a voltage follower (such as TL071) can be added at the output to enhance the driving capability, directly coupled to the reference voltage end of the voltage operator 6 (usually a high-impedance input).

[0079] Simulation verification 1: input dynamic range compression to target output range

[0080] 1. Simulation conditions

[0081] Input signal range: -85dBm~+15dBm (dynamic range 100dB);

[0082] Target output range: -62dBm~+2dBm (dynamic range 64dB);

[0083] Detector parameters: Logarithmic detector 5 best dynamic range: -40dBm~+10dBm (50dB), using broken line approximation detection curve;

[0084] Coupler 2 coupling degree: 10dB, used to extract input signal power for detection.

[0085] 2. System working principle and simulation results

[0086] Compression mechanism within the dynamic range of detector 5:

[0087] After the input signal passes through the 10dB coupler 2, the coupled signal power range is -95dBm~+5dBm. Among them, the coupled signal falling within the best dynamic range of detector 5 (-40dBm~+10dBm) (corresponding to the original input signal range: -30dBm~+20dBm, the actual input upper limit is +15dBm, so the effective input section is -30dBm~+15dBm) is linearly responded by detector 5, and the detection voltage is processed by voltage operator 6 to control controllable amplitude adjuster 3, reducing the input-output curve slope (solid line), which compresses the original 100dB input dynamic range to the target 64dB output range (-62dBm~+2dBm).

[0088] Linear maintenance mechanism outside the dynamic range of detector 5:

[0089] For the case where the coupled signal power is lower than the noise floor of detector 5 (-40dBm, corresponding to the original input signal -30dBm) or higher than the saturation voltage of detector 5 (>+10dBm, corresponding to the original input signal >+20dBm, the actual input does not reach this upper limit), the output voltage of detector 5 tends to a fixed value (noise floor or saturation voltage), resulting in a fixed control voltage output by voltage operator 6, and the attenuation of controllable amplitude adjuster 3 remains constant. At this time, the input-output curve slope returns to 1dB / dB (dashed line), ensuring that the input signal outside the dynamic range of detector 5 is still transmitted in a linear relationship, avoiding distortion or exceeding the target range of the output signal.

[0090] 3. Simulation conclusion

[0091] As Figure 3As shown, the system realizes output compression through slope adjustment within the dynamic range of the detector 5, and keeps linearity through fixed attenuation outside the dynamic range, finally stabilizes the 100dB input dynamic range to the 64dB target output range.

[0092] Simulation verification 2: input dynamic range is expanded to target output range

[0093] 1. Simulation conditions

[0094] Input signal range: -80dBm~ -50dBm (dynamic range 30dB);

[0095] Target output range: -62dBm~ +2dBm (dynamic range 64dB);

[0096] Detector 5 parameters: same as simulation verification 1.

[0097] 2. System working principle and simulation results

[0098] Expansion mechanism within the dynamic range of the detector 5:

[0099] After the input signal passes through the 10dB coupler 2, the coupled signal power range is -90dBm~ -60dBm. At this time, the detector 5 only responds to the part of the coupled signal close to the lower limit of the optimal dynamic range (-60dBm~ -40dBm, corresponding to the original input signal -50dBm~ -30dBm, the actual input upper limit is -50dBm, so the effective input section is -80dBm~ -50dBm). After the detector voltage is processed by the voltage operator 6, the input-output curve slope (solid line) is increased by controlling the controllable amplitude adjuster 3, which expands the original 30dB input dynamic range to the target 64dB output range (-62dBm~ +2dBm).

[0100] Linearity guarantee of the expansion process:

[0101] Since the input signal as a whole is weak (-80dBm~ -50dBm), the coupled signal does not reach the saturation region of the detector 5, and the detector 5 works in the linear response section (broken line approximation). Through the amplification processing of the detector voltage by the voltage operator 6, the attenuation amount of the controllable amplitude adjuster 3 decreases with the increase of the input signal, realizing the "nonlinear amplification" of the input power, and finally expanding the narrow dynamic range input signal to the wide dynamic range output, and the curve slope is uniform during the expansion process, without obvious distortion.

[0102] 3. Simulation conclusion

[0103] As Figure 4As shown, the system successfully expands the 30dB narrow input dynamic range to the 64dB target output range by improving the input-output slope in the dynamic range of the detector 5, verifying the system's ability to expand small dynamic range input signals.

[0104] Based on the above circuit structure, the second embodiment of the present application discloses a method for linearly adjusting the output dynamic range. Referring to Figure 5 A method for linearly adjusting the output dynamic range, comprising:

[0105] S1, input signal preprocessing and coupling sampling;

[0106] The first fixed amplitude adjuster 1 receives the input signal and pre-adjusts the input signal according to the initial amplitude characteristics of the input signal, so that the signal enters the linear working interval of the main channel; the adjusted signal is transmitted to the coupler 2, and the coupler 2 couples part of the signal energy to the detector 5 with a coupling degree of not less than 10dB, ensuring that the signal amplitude coupled to the detector 5 falls within its optimal dynamic range interval, and the main channel signal continues to be transmitted to the controllable amplitude adjuster 3;

[0107] S2, signal amplitude detection and control signal generation;

[0108] The detector 5 detects the amplitude of the sampled signal output by the coupler 2, and selects the type of detector 5 according to the characteristics of the input signal: the detector 5 outputs a direct current voltage signal related to the power or amplitude of the input signal, which is transmitted to the voltage operator 6, and the voltage operator 6 compares the voltage with a reference threshold to generate an initial control signal for adjusting the controllable amplitude adjuster 3;

[0109] S3, amplitude adjustment;

[0110] The controllable amplitude adjuster 3 switches the working mode according to the control signal and the system's demand for the output dynamic range, to realize linear dynamic control of the amplitude of the main channel signal:

[0111] If the output dynamic range needs to be expanded, the gain is increased through the control signal; if the output dynamic range needs to be reduced, the attenuation amount is increased through the control signal;

[0112] S4, output amplitude calibration;

[0113] The signal output by the controllable amplitude adjuster 3 is transmitted to the second fixed amplitude adjuster 4, which adjusts the signal amplitude to the target range according to the final output amplitude requirement and outputs.

[0114] ​The above are only preferred embodiments of the present application and are not used to limit the protection scope of the present application. Any feature disclosed in the specification (including the abstract and drawings) can be replaced by other equivalent or similar features unless otherwise stated. That is, each feature is only an example of a series of equivalent or similar features unless otherwise stated.

Claims

1. A circuit structure for linearly adjusting an output dynamic range, characterized by, The circuit structure comprises: a first fixed amplitude adjuster (1) having an input end receiving an input signal; a coupler (2) having an input end electrically connected to an output end of the first fixed amplitude adjuster (1) and having a coupling degree not less than 10 dB; a controllable amplitude adjuster (3) having an input end electrically connected to an output end of the coupler (2); a second fixed amplitude adjuster (4) having an input end electrically connected to an output end of the controllable amplitude adjuster (3) and having an output end for outputting an adjusted output signal; a detector (5) having an input end electrically connected to a regulating end of the coupler (2); a voltage operator (6) having an input end electrically connected to an output end of the detector (5) and generating a control signal according to a voltage amplitude output by the detector (5); a dynamic response compensation module (7) having an input end electrically connected to an output end of the voltage operator (6) and having an output end electrically connected to a regulating end of the controllable amplitude adjuster (3); the dynamic response compensation module (7) is configured to dynamically adjust a response time of the control signal according to a change rate of the input signal, comprising: when the input signal amplitude change rate is higher than a preset threshold, the rising / falling time of the control signal is shortened to avoid signal overshoot or under-adjustment; when the input signal amplitude change rate is lower than the preset threshold, the response time of the control signal is prolonged to reduce the interference of noise on the signal.

2. The circuit structure for linearly adjusting output dynamic range according to claim 1, wherein, the detector (5) comprises an RMS detector, a logarithmic detector and a diode detector; when the output dynamic range of the required signal is linear with the input signal dynamic range in dB, the detector (5) is switched to an RMS detector or a logarithmic detector.

3. The circuit structure for linearly adjusting output dynamic range according to claim 2, wherein, the circuit structure for linearly adjusting the output dynamic range further comprises: when the peak-to-average ratio of the input signal is greater than a set value, the detector (5) is switched to an RMS detector; when the peak-to-average ratio of the input signal is less than or equal to the set value, the detector (5) is switched to a logarithmic detector.

4. The circuit structure of claim 1, wherein, the first fixed amplitude adjuster (1) and the second fixed amplitude adjuster (4) each comprise a linear amplifier and a fixed attenuator; when the signal amplitude is reduced, the first fixed amplitude adjuster (1) and / or the second fixed amplitude adjuster (4) is switched to a fixed attenuator; when the signal amplitude is increased, the first fixed amplitude adjuster (1) and / or the second fixed amplitude adjuster (4) is switched to a linear amplifier.

5. The circuit structure of claim 1, wherein, the controllable amplitude adjuster (3) comprises an attenuator and a controllable amplifier; when the dynamic range of the signal is expanded, the controllable amplitude adjuster (3) is switched to a controllable amplifier; when the dynamic range of the signal is reduced, the controllable amplitude adjuster (3) is switched to an attenuator, which is a digital attenuator or an electrically adjustable attenuator.

6. The circuit structure for linearly adjusting output dynamic range according to claim 1, wherein, the circuit structure further comprises: an adaptive threshold calibration module (8) having input ends respectively electrically connected to output ends of the detector (5) and the second fixed amplitude adjuster (4) and having an output end electrically connected to a reference voltage end of the voltage operator (6); the adaptive threshold calibration module (8) is configured to: monitor a deviation value between an actual dynamic range of the output signal and a target dynamic range in real time; The reference threshold of the voltage calculator (6) is dynamically adjusted according to the deviation value.

7. A method of linearly adjusting an output dynamic range, characterized by, The circuit structure is suitable for linearly adjusting the output dynamic range, and comprises: S1, input signal preprocessing and coupling sampling; The first fixed amplitude adjuster (1) receives an input signal, and pre-adjusts the input signal according to initial amplitude characteristics of the input signal, so that the signal enters a linear working interval of a main channel; the adjusted signal is transmitted to a coupler (2), and the coupler (2) couples part of signal energy to a detector (5) with a coupling degree not less than 10 dB, so as to ensure that the signal coupled to the detector (5) falls in an optimal interval of a dynamic range of the detector (5), and the main channel signal continues to be transmitted to a controllable amplitude adjuster (3); S2, signal amplitude detection and control signal generation; The detector (5) detects the amplitude of the sampling signal output by the coupler (2), selects a type of the detector (5) according to characteristics of the input signal, and outputs a direct current voltage signal related to the power or amplitude of the input signal to the voltage calculator (6); the voltage calculator (6) compares the direct current voltage signal with a reference threshold, and generates an initial control signal for adjusting the controllable amplitude adjuster (3); S3, amplitude adjustment; The controllable amplitude adjuster (3) switches a working mode according to the control signal and in combination with a demand of the system for the output dynamic range, so as to realize linear dynamic control of the amplitude of the main channel signal; If it is necessary to expand the output dynamic range, the gain is increased through the control signal; if it is necessary to reduce the output dynamic range, the attenuation amount is increased through the control signal; S4, output amplitude calibration; The signal output by the controllable amplitude adjuster (3) is transmitted to the second fixed amplitude adjuster (4), and the second fixed amplitude adjuster (4) adjusts the signal amplitude to a target range according to a final output amplitude requirement and outputs the signal.

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