Satellite communication digital signal adaptive amplification method and system based on link sensing

Abstract

This invention relates to the field of satellite communication technology, and more particularly to a link-aware adaptive amplification method and system for satellite communication digital signals. The method includes the following steps: acquiring and analyzing the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and performing a joint power boundary determination to form a limit saturation state word; analyzing the link quality deficit value using the limit saturation state word; performing energy spectral density compensation conversion on the link quality deficit value to obtain a bandwidth compression coefficient; performing equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain a rate reduction configuration parameter; calculating the energy loss in decibels based on the rate reduction configuration parameter to determine the gain compensation coefficient. This invention, by implementing digital-analog collaborative control under the physical saturation limit of the power amplifier, achieves an increase in signal power spectral density while maintaining a constant total transmit power, thereby breaking through the hardware transmission limit in extremely harsh channels to maintain the communication link.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a link-aware adaptive amplification method and system for satellite communication digital signals. Background Technology

[0002] Existing satellite communication technologies face severe bottlenecks once the power amplifier reaches its physical saturation limit. When the power amplifier is fully saturated and the link is still underperforming, traditional ACM technology has no choice but to reduce the modulation order and coding rate. Once the lowest-order modulation fails to meet the reception threshold, the communication link will be interrupted, leading to the interruption of critical services and a severe decline in user experience. At the same time, traditional link adaptive technology often reduces the transmit power simultaneously to maintain a constant power spectral density when reducing the symbol rate. Although this approach complies with conventional spectrum management regulations, it results in a serious waste of the remaining potential energy in the amplifier's saturation region, failing to fully utilize the hardware's potential under extreme conditions. Furthermore, in ultra-narrowband emergency communication application scenarios, the significant compression of signal bandwidth often leads to a natural decrease in the time domain envelope amplitude, making it difficult to fully drive the final-stage power amplifier to its high-efficiency operating region. This creates a technical bottleneck of narrow bandwidth but low power amplifier efficiency, severely restricting the system's performance under extreme link conditions.

[0003] In summary, existing technologies generally suffer from problems such as the inability to maintain the link after the power amplifier saturates, the disconnect between bandwidth adjustment and power control, and the low efficiency of power amplifiers driven by narrowband signals, which urgently need to be addressed. Summary of the Invention

[0004] Therefore, it is necessary to provide a link-aware adaptive amplification method and system for satellite communication digital signals to solve at least one of the above-mentioned technical problems.

[0005] To achieve the above objectives, a link-aware adaptive amplification method for satellite communication digital signals includes the following steps:

[0006] Step S1: Collect and analyze the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and perform a joint power boundary determination to form the limit saturation state word;

[0007] Step S2: Analyze the link quality loss value using the limit saturation state word; perform energy spectral density compensation conversion on the link quality loss value to obtain the bandwidth compression coefficient; perform equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain the rate reduction configuration parameters;

[0008] Step S3: Calculate the energy loss in decibels based on the descent rate configuration parameters; determine the gain compensation coefficient based on the energy loss in decibels; convert the gain compensation coefficient into a control voltage adjustment amount, and synthesize the saturation bias voltage to form the saturation drive bias voltage value;

[0009] Step S4: Generate a narrowband digital baseband signal based on the rate reduction configuration parameters, and apply pre-gain compensation by combining the saturation drive bias voltage value to form a gain-compensated intermediate frequency signal; optimize the power amplifier operating point control of the gain-compensated intermediate frequency signal to obtain a saturated power RF carrier; perform monitoring and transmission on the saturated power RF carrier to form an enhanced power spectral density RF signal.

[0010] This invention accurately identifies the extreme deadlock state where the signal-to-noise ratio is insufficient and the power has reached the physical limit through a power boundary joint judgment method, avoiding ineffective adjustments by traditional methods. It utilizes a discrete rate matching strategy with floor function to accurately convert link deficit into a reduction in physical bandwidth, establishing a positive energy margin while ensuring compatibility. By introducing a full-power reverse gain compensation algorithm with nonlinear correction, it effectively overcomes the natural energy drop caused by narrowband transmission and the gain compression effect in the power amplifier saturation region. Combining digital domain full-scale normalization with the coordinated control of analog pre-amplifier powerful drive solves the problem that weak signals in extremely narrowband are difficult to drive high-power amplifiers into the high-efficiency saturation region. Furthermore, dynamic bias closed-loop correction eliminates the impact of device thermal drift on output power, ensuring continuous radiation of highly concentrated RF signals without upgrading hardware specifications, significantly improving link survivability and penetration distance under extreme rain attenuation environments.

[0011] Preferably, the present invention also provides a link-aware adaptive amplification system for satellite communication digital signals, used to execute the link-aware adaptive amplification method for satellite communication digital signals as described above, the link-aware adaptive amplification system for satellite communication digital signals comprising:

[0012] The limit state detection module is used to collect and analyze the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and perform a joint determination of the power boundary to form the limit saturation state word;

[0013] The bandwidth compression calculation module is used to analyze the link quality loss value using the limit saturation state word; perform energy spectral density compensation conversion on the link quality loss value to obtain the bandwidth compression coefficient; and perform equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain the rate reduction configuration parameters.

[0014] The gain compensation generation module is used to calculate the energy loss decibel value based on the descent rate configuration parameters; determine the gain compensation coefficient based on the energy loss decibel value; convert the gain compensation coefficient into the control voltage adjustment amount; and synthesize the saturation bias voltage to form the saturation drive bias voltage value.

[0015] The high-density signal transmission module is used to generate a narrowband digital baseband signal based on the rate-down configuration parameters, and to perform pre-gain compensation application in combination with the saturation drive bias voltage value to form a gain-compensated intermediate frequency signal; the power amplifier operating point of the gain-compensated intermediate frequency signal is optimized and controlled to obtain a saturated power RF carrier; the saturated power RF carrier is monitored and transmitted to form an enhanced power spectral density RF signal.

[0016] This system, through the coordinated operation of limit state detection, bandwidth compression calculation, gain compensation generation, and high-density signal transmission modules, can accurately trigger the "equal-energy bandwidth compression" and "full-power reverse gain compensation" strategies under the physical limit of power saturation. Through deep linkage control between the digital and analog domains, it ensures a significant increase in the power spectral density of the transmitted signal without changing the hardware architecture, thereby effectively solving the link interruption problem in harsh channel environments and greatly improving the system's anti-interference and penetration capabilities. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the steps of a link-aware adaptive amplification method for digital signals in satellite communication. Detailed Implementation

[0018] The technical method of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0019] Furthermore, the accompanying drawings are merely illustrative of the invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor methods and / or microcontroller methods.

[0020] It should be understood that although the terms "first," "second," etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are used merely to distinguish one unit from another. For example, without departing from the scope of the exemplary embodiments, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] To achieve the above objectives, please refer to Figure 1 This invention provides a link-aware adaptive amplification method for digital signals in satellite communication, comprising the following steps:

[0022] Step S1: Collect and analyze the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and perform a joint power boundary determination to form the limit saturation state word;

[0023] In this embodiment of the invention, the signal-to-noise ratio margin is obtained by subtracting the difference between the received signal-to-noise ratio and the communication threshold. At the same time, the power saturation percentage is calculated by comparing the measured output power with the rated saturation power. Then, a preset threshold table is queried, and if and only if the signal-to-noise ratio margin is negative and the power saturation percentage exceeds 95%, it is determined that the system has entered a limit state. Finally, the determination result is bit-concatenated with the system operating mode identifier to generate a limit saturation state word indicating the start of adaptive adjustment.

[0024] Step S2: Analyze the link quality loss value using the limit saturation state word; perform energy spectral density compensation conversion on the link quality loss value to obtain the bandwidth compression coefficient; perform equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain the rate reduction configuration parameters;

[0025] In this embodiment of the invention, the calculation process is triggered by parsing the limit saturation state word, and the difference between the communication threshold and the real-time signal-to-noise ratio is converted into a link quality loss value. Then, the theoretical bandwidth compression ratio is calculated based on energy conservation and logarithmic inverse operation, and the closest level is selected from the discrete symbol rate table supported by the hardware as the rate reduction configuration parameter according to the floor strategy. At the same time, the final bandwidth compression coefficient is determined by combining the modulation mode compatibility check, and the physical layer parameters that sacrifice bandwidth to obtain energy margin are established.

[0026] Step S3: Calculate the energy loss in decibels based on the descent rate configuration parameters; determine the gain compensation coefficient based on the energy loss in decibels; convert the gain compensation coefficient into a control voltage adjustment amount, and synthesize the saturation bias voltage to form the saturation drive bias voltage value;

[0027] In this embodiment of the invention, the energy loss in decibels caused by bandwidth narrowing is calculated based on the actual bandwidth compression ratio, and the inverse value is taken as the theoretical linear gain compensation requirement. Then, combined with the amplifier gain-control voltage nonlinear characteristic curve, the additional control voltage adjustment required to offset the gain compression in the saturation region is calculated. Finally, this adjustment is superimposed on the current operating voltage, and after hardware safety boundary limiting and saturation region gain flatness fine-tuning, a saturation drive bias voltage value that can drive the amplifier to a deep saturation state is synthesized.

[0028] Step S4: Generate a narrowband digital baseband signal based on the rate reduction configuration parameters, and apply pre-gain compensation by combining the saturation drive bias voltage value to form a gain-compensated intermediate frequency signal; optimize the power amplifier operating point control of the gain-compensated intermediate frequency signal to obtain a saturated power RF carrier; perform monitoring and transmission on the saturated power RF carrier to form an enhanced power spectral density RF signal;

[0029] In this embodiment of the invention, a narrowband signal is generated by controlling the digital baseband and performing digital domain amplitude normalization. A high-level intermediate frequency signal is generated by controlling the analog front-end using a saturation drive bias voltage to overcome the input threshold of the subsequent power amplifier. Subsequently, based on real-time temperature and power monitoring data, the gate bias voltage of the power amplifier is dynamically fine-tuned to lock it in the optimal saturation range of gain compression characteristics, eliminating the influence of thermal drift. Finally, the power spectral density is confirmed to meet the standard through spectrum monitoring, and the antenna feed matching network is fine-tuned to minimize reflection loss, ultimately radiating a highly concentrated enhanced power spectral density radio frequency signal.

[0030] Preferably, step S1 includes:

[0031] The signal-to-noise ratio (SNR) data is compared with a preset communication sustaining threshold value to calculate the SNR margin value.

[0032] Collect the current amplifier output power, measure the power saturation, and obtain the power saturation percentage;

[0033] Using a preset threshold parameter table, a dual-parameter threshold determination is performed on the signal-to-noise ratio margin and power saturation percentage to generate the limit state determination result;

[0034] Obtain the system operating mode identifier, combine it with the limit state determination result to generate the state word encoding, and obtain the limit saturation state word.

[0035] In one embodiment, the specific implementation of the joint determination of power boundaries in step S1 is as follows:

[0036] First, receive real-time signal-to-noise ratio data from the target terminal via the satellite backhaul link. The processor reads the preset communication sustaining threshold from the memory unit. This threshold value represents the minimum demodulation threshold required to maintain the required bit error rate under the current modulation and coding strategy. The system performs a subtraction operation to calculate the signal-to-noise ratio margin value. The calculation logic is as follows:

[0037] ;

[0038] in A negative value indicates a current link quality loss. Simultaneously, the system controls the RF directional coupler and logarithmic detector circuit to acquire the current output power value of the transmit amplifier. The system retrieves the rated saturation power constant from the amplifier's hardware parameters. and according to the formula Calculate the percentage of power saturation This value reflects how close the amplifier's current operating point is to the physical saturation limit.

[0039] Subsequently, the system queries the pre-stored threshold parameter table to extract the saturation determination threshold. (Specifically set to 95%). The system executes a two-parameter logical AND decision: if and only if and When both conditions are met, the system sets the extreme state determination result to valid (logic high level) to accurately identify the deadlock state of "link loss and no room for power increase". Finally, the system reads the system operating mode identifier from the register (used to distinguish whether the current service is an emergency mode that needs to be guaranteed). The system maps the extreme state determination result to the high-order flag bit of the status word and the system operating mode identifier to the low-order information bit. Through bit concatenation operations, a multi-bit binary encoded sequence is generated and output as the extreme saturation status word, which serves as the sole trigger instruction for subsequently starting the bandwidth-to-energy conversion process.

[0040] Preferably, step S2 includes:

[0041] The state word of the limit saturation state word is parsed and conditionally triggered to obtain the compressed calculation activation flag;

[0042] Based on the compression calculation activation flag and the preset communication maintenance threshold, a link quality difference analysis is performed to obtain the link quality loss value.

[0043] Obtain the current symbol rate value, and perform a correlation calculation between symbol rate and bandwidth using the bandwidth compression factor to obtain the target symbol rate value;

[0044] Hardware compatibility constraints are applied based on the target symbol rate value and a predefined symbol rate support table to obtain the rate reduction configuration parameters.

[0045] In one embodiment, the specific implementation of the equal-energy bandwidth compression calculation in step S2 is as follows:

[0046] First, a bitmask extraction operation is performed on the limit saturation state word to parse the limit state flag bit. If the flag bit is valid, the system sets the compression calculation activation flag, triggering the subsequent adaptive calculation process. The processor then reads the real-time signal-to-noise ratio data. Communication maintenance threshold Perform interpolation Calculate link quality loss value This value, expressed in decibels, precisely quantifies the current energy deficit of the link.

[0047] Based on this, the system establishes a bandwidth adjustment target according to the principle of energy conservation. The system first obtains the bandwidth compression coefficient according to the energy spectral density compensation conversion logic in the following embodiment. Subsequently, the system reads the current symbol rate value of the digital baseband. And combined with the preset raised cosine filter roll-off coefficient According to the formula Calculate the target symbol rate value This calculation process establishes the precise symbol rate theoretically required to achieve power spectral density gain by compressing the spectrum.

[0048] Considering the discrete nature of hardware clock frequency division, the system calls the predefined symbol rate support table in the memory unit (this table contains all discrete symbol rate levels supported by the system hardware, such as 5Msps, 2.5Msps, 1.25Msps, etc.). The system executes a floor function search algorithm to find the closest symbol rate less than the specified value in the symbol rate support table. The system locks this selected discrete rate value as the rate-down configuration parameter and writes it into the clock control register of the digital baseband processor. By using a round-down strategy, it ensures that the actual configured bandwidth is slightly narrower than the theoretical requirement, thereby generating a positive energy margin to guarantee the absolute reliability of the link under extreme conditions.

[0049] Preferably, the energy spectral density compensation conversion of the link quality loss value in step S2 includes:

[0050] The link quality loss value is normalized by performing link loss decibel normalization to obtain the normalized loss decibel value.

[0051] The theoretical bandwidth compression ratio is calculated based on the normalized loss decibel value.

[0052] Map the theoretical bandwidth compression ratio to discrete compression ratios;

[0053] Obtain the current modulation scheme, perform modulation scheme compatibility analysis based on discrete bit compression ratio, and determine the bandwidth compression coefficient.

[0054] In one embodiment, the specific implementation of the energy spectral density compensation conversion in step S2 is as follows:

[0055] First, the link quality loss value in decibels is input. Perform positive value normalization to ensure that the input is positive, and generate a normalized loss decibel value. Subsequently, based on the bandwidth-power spectral density interchange model under the assumption of constant total transmit power, the system performs logarithmic inverse operation to calculate the theoretical bandwidth compression ratio. The operational logic follows the formula. For example, when the loss is 3dB, it is calculated that the bandwidth should theoretically be compressed to about 0.5 times the original value.

[0056] Next, the system will process the consecutive floating-point values. The value is compared with a pre-set set of discrete compression levels in the system (such as 1 / 2, 1 / 4, 1 / 8, 1 / 16, etc.). The system executes downward truncation matching logic, selecting the value that is less than and closest to the specified value. The gear position is used as the discrete gear compression ratio. For example, if the theoretically calculated value is 0.6, the system will force the selection of the 0.5 level, thereby sacrificing more bandwidth to achieve a higher-than-expected signal-to-noise ratio gain.

[0057] Finally, the system reads the current modulation scheme of the modem (e.g., QPSK, 8PSK, etc.). The system queries the pre-stored modulation-bandwidth limit table to verify the discrete-bit compression ratio. Will the current modulation scheme cause excessive inter-symbol interference or exceed the demodulator lockout range? If the check passes, proceed directly... The bandwidth compression factor is determined; if the verification fails (e.g., the high sensitivity to phase noise of high-order modulation at extremely low rates), the system automatically triggers modulation down-order logic (e.g., down-modulating from 8PSK to QPSK), and re-matches the minimum available compression ratio that conforms to the new modulation method, finally outputting the bandwidth compression factor that has been confirmed for compatibility, ensuring the closed-loop stability of physical layer parameter adjustment.

[0058] Preferably, step S3 includes:

[0059] Obtain the original symbol rate value, combine it with the rate reduction configuration parameters to calculate the bandwidth compression ratio, and obtain the actual bandwidth compression ratio;

[0060] The energy loss in decibels is estimated and calculated based on the actual bandwidth compression ratio.

[0061] The gain compensation coefficient is converted into circuit control parameters based on the gain and control voltage characteristic curve data of the amplifier to obtain the control voltage adjustment amount;

[0062] Obtain the current operating voltage value of the amplifier and synthesize it with the control voltage adjustment amount to form a saturation drive bias voltage value.

[0063] In one embodiment, the full-power compensation gain mapping in step S3 is implemented as follows:

[0064] First, read the original symbol rate value before adaptive adjustment. This is compared with the descent rate configuration parameters determined in step S2. Perform ratio calculations according to the formula. The actual bandwidth compression ratio is calculated. Subsequently, based on signal processing principles, the system estimates the natural drop in integral energy caused by bandwidth narrowing and performs logarithmic calculations. The energy loss in decibels is calculated (this value is negative, for example, -3dB corresponds to half the bandwidth).

[0065] Based on this, the system determines the required positive gain compensation amount according to the compensation coefficient generation logic in the following embodiment. The system then retrieves the amplifier gain-control voltage characteristic curve data (V-GCurve) from the storage unit. Using the gain compensation coefficient as an index, the system performs a nonlinear interpolation search on the characteristic curve to determine the control voltage difference required to achieve the gain increment, i.e., the control voltage adjustment amount. This process takes into account the nonlinear slope of the amplifier's voltage-controlled characteristics, ensuring that the voltage adjustment precisely corresponds to the expected gain change.

[0066] Finally, the system reads the control voltage value of the amplifier under its current operating state through the analog-to-digital converter interface. The system performs an addition operation. Voltage synthesis is performed. Simultaneously, the system incorporates hardware safety boundary verification logic to compare the synthesized result with the preset maximum safe voltage of the amplifier. and minimum starting voltage After comparison and limiting, a saturation drive bias voltage value that conforms to hardware safety specifications and can drive the amplifier to a high-gain state is finally generated.

[0067] Most importantly, the process of obtaining the amplifier's current operating voltage and synthesizing it with the control voltage adjustment to form a saturation bias voltage involves the following steps:

[0068] Calculate the initial bias voltage based on the control voltage adjustment and the current operating voltage value;

[0069] Obtain and verify whether the initial bias voltage is within the safe operating range based on the device safety threshold parameters, and perform safety range control to generate a safety boundary bias voltage;

[0070] Optimize the amplifier saturation state of the safety boundary bias voltage to generate a saturation-optimized bias voltage;

[0071] The saturation-optimized bias voltage is nonlinearly compensated and adjusted using a bandwidth compression coefficient to obtain the saturation drive bias voltage.

[0072] In one embodiment, the specific implementation of the saturation bias voltage synthesis process in step S3 is as follows:

[0073] Perform a reference superposition operation to sample the control voltage value that maintains the amplifier's operation at the current moment. The control voltage adjustment amount calculated in the previous steps By performing algebraic summation, the theoretical initial bias voltage can be obtained. Subsequently, the system calls the pre-stored device safety threshold parameters (including the upper limit of gate breakdown voltage). With the lower limit of the pinch-off voltage The system executes numerical comparison logic: if Then the voltage will be forcibly clamped to ;like Then clamp to Otherwise, the original value is retained, thereby generating a safety boundary bias voltage that conforms to electrical safety specifications. .

[0074] Based on this, the system performs fine-tuning for the characteristics of the saturation region. The system loads a preset gain flatness curve for the saturation region and, according to... Within the given voltage range, fine-tune the voltage value to avoid the non-monotonic region where the gain drops sharply, find the operating point where the local gain is maximized, and generate a saturation-optimized bias voltage. Finally, the system introduces bandwidth as a correction factor. Since the peak-to-average power ratio (PAPR) changes after the signal bandwidth narrows, the system utilizes the bandwidth compression coefficient. Query the nonlinear compensation lookup table (LUT) to obtain the corresponding voltage correction bias. The system performs the final calculation. The optimized voltage is compensated to counteract the nonlinear compression effect unique to narrowband signals in the saturation region, and the final output is a saturation drive bias voltage that can precisely control the amplifier to achieve the optimal saturation depth in narrowband mode.

[0075] Preferably, determining the gain compensation coefficient based on the energy loss in decibels in step S3 includes:

[0076] Based on the energy loss in decibels, and combined with the preset bandwidth and gain compensation table, the bandwidth compression energy loss is calculated to obtain the theoretical gain compensation value.

[0077] The power amplifier characteristic curve data is obtained by querying the theoretical gain compensation value.

[0078] The nonlinearity compensation factor is calculated based on the power amplifier characteristic curve data and theoretical gain compensation value to obtain the nonlinearity correction factor;

[0079] The theoretical gain compensation value is compensated using a nonlinear correction factor to form a gain compensation coefficient.

[0080] In one embodiment, the specific implementation of determining the gain compensation coefficient in step S3 is as follows:

[0081] The system reads the energy loss value in decibels (e.g., -3dB, representing the natural energy drop caused by halving the bandwidth) calculated in the previous step. It then inverts this value and queries a preset bandwidth and gain compensation table (which stores the linear compensation relationship required to maintain a constant total energy per unit time) to directly derive the theoretical gain compensation value used to offset this natural energy drop. (e.g., +3dB).

[0082] Considering the gain compression effect of the power amplifier at high power output, the system immediately retrieves the power amplifier characteristic curve data (AM-AM curve) from the storage unit. The system uses the current operating point as the starting point... To determine the target increment, a tangent slope analysis is performed on the curve. The system calculates the attenuation (i.e., compression) of the actual output gain relative to the ideal linear gain at the target output power point. or (The offset value of the point). Based on this attenuation, the system calculates the additional driving force required and generates a nonlinear correction factor. For example, if a 3dB increase in output in the saturation region actually requires a 4dB increase in input drive, then the correction factor is 1dB.

[0083] Finally, the system performs the superposition operation. This process combines linear overdrive requirements with nonlinear overdrive requirements. This ensures that the final gain compensation coefficient not only compensates for the energy deficit caused by narrower bandwidth but also overcomes compression losses in the power amplifier's saturation region, thus providing sufficient drive gain to push the amplifier to the expected full-power output state.

[0084] Preferably, step S4, which generates a narrowband digital baseband signal based on the rate-drop configuration parameters and performs pre-gain compensation in conjunction with the saturation drive bias voltage value, includes:

[0085] Based on the down-rate configuration parameters, the symbol rate clock is adjusted to perform baseband data stream adjustment and generate a narrowband digital baseband signal;

[0086] Narrowband signal envelope analysis is performed on narrowband digital baseband signals to obtain narrowband signal characteristic parameters;

[0087] The gain control voltage value of the saturation drive bias voltage is converted by using the narrowband signal characteristic parameters to obtain the analog gain control signal;

[0088] The compensation front-end circuit is selected based on the analog gain control signal, and a compensation circuit configuration instruction is generated.

[0089] Dynamic gain adjustment is performed according to the compensation circuit configuration instructions to obtain the intermediate frequency gain adjustment signal;

[0090] Obtain the target value for the gain setting, combine it with the intermediate frequency gain adjustment signal to perform gain locking and steady-state confirmation, and generate a gain lock status word;

[0091] The intermediate frequency gain adjustment signal is verified and output based on the gain lock status word, and the intermediate frequency gain adjustment signal is used as the gain compensation intermediate frequency signal.

[0092] In one embodiment, the specific implementation of narrowband signal generation and pre-gain compensation in step S4 is as follows:

[0093] The digital baseband processor first responds to the rate reduction configuration parameters, resetting the clock division ratio of the numerically controlled oscillator (NCO) and interpolation filter to adjust the symbol rate to the target low-speed level (e.g., reducing it from 10 Msps to 5 Msps), and then remodulates and shapes the original service data stream to generate a narrowband digital baseband signal with compressed bandwidth. Subsequently, the system performs digital domain amplitude analysis, statistically analyzing the peak-to-average power ratio (PAPR) and amplitude histogram of the narrowband signal within the current time window to generate narrowband signal characteristic parameters.

[0094] This characteristic parameter is used to correct and map the input saturation drive bias voltage value. Considering the envelope fluctuation characteristics of narrowband signals, the system converts the single bias voltage value into an analog gain control signal (usually in the form of differential voltage or PWM duty cycle) adapted to the control characteristics of the analog variable gain amplifier (VGA) through a lookup table. Based on the amplitude range of this control signal, the system logic determines whether multi-stage cascaded amplification needs to be enabled. If the control signal indicates that the required gain exceeds the linear range of a single-stage VGA (e.g., greater than 30dB), the system generates a compensation circuit configuration instruction to activate the preamplifier (Driver Amp), constructing a high-gain link.

[0095] The hardware circuit then responds to the command, switching the RF path via an analog switch and applying a control voltage to significantly boost the gain of the analog signal after digital-to-analog conversion (DAC), generating a high-level intermediate frequency (IF) gain adjustment signal. The system synchronously acquires the output power detection value of this signal and performs a closed-loop comparison with the system's preset gain target value (i.e., the theoretical level required to drive the final stage power amplifier to saturation). When the detected value stabilizes within the target value error range (e.g., ±0.5dB) for several consecutive clock cycles, the system sets the gain lock status word. Finally, the system verifies the validity of this status word and checks for signal clipping distortion. Once confirmed to be correct, it opens the output stage RF switch, transmitting this stable and high-drive IF gain adjustment signal as the gain compensation IF signal to the final stage power amplifier unit.

[0096] Preferably, step S4, which optimizes the power amplifier operating point control of the gain-compensated intermediate frequency signal, includes:

[0097] The power amplifier saturation characteristics of the gain-compensated intermediate frequency signal are analyzed using the pre-stored power amplifier transfer characteristic curves to obtain the theoretical operating point data of the power amplifier.

[0098] Based on the power amplifier's theoretical operating point data and bandwidth compression coefficient, the saturation region is located to obtain the target saturation range.

[0099] Real-time power amplifier status monitoring is performed based on the saturation target range to obtain the power amplifier operating status deviation.

[0100] Nonlinear distortion monitoring and compensation are performed on the power amplifier's operating state deviation to obtain the bias adjustment parameters;

[0101] The bias adjustment parameters are converted into power amplifier control data and dynamic bias control processing is performed to obtain an optimized bias power amplifier signal.

[0102] The operating point power amplifier is stabilized by optimizing the bias power amplifier signal and the saturation target range to form a saturated power RF carrier.

[0103] In one embodiment, the specific implementation of the power amplifier operating point optimization control in step S4 is as follows:

[0104] Recall the pre-calibrated power amplifier transfer characteristic curve in memory ( - The system generates the theoretical operating point data of the amplifier by finding the corresponding static output power prediction value and efficiency parameters on the curve based on the amplitude level of the input gain-compensated intermediate frequency signal. Subsequently, the system introduces a narrowband correction factor in conjunction with the bandwidth compression coefficient. Since the energy of the narrowband signal is more concentrated in the frequency domain, the system defines a specific gate voltage control range based on the theoretical operating point. This range defines the maximum saturation depth of the amplifier without hard clipping, i.e., the saturation target range (e.g., gain compression between 1dB and 3dB).

[0105] Closed-loop monitoring is then initiated, using temperature sensors and directional couplers to collect the amplifier's die temperature and actual output power in real time. The system calculates the difference between the actual measured value and the theoretical operating point data to obtain the power amplifier's operating state deviation (such as a 0.5dB gain back-off due to thermal effects). To address this deviation, the system simultaneously monitors the adjacent channel power leakage ratio (ACPR). If the ACPR deteriorates, indicating excessive nonlinear distortion, the system calculates the required gate voltage back-off; if the ACPR is normal but the power is insufficient, the system calculates the required increase in gate voltage, and the bias adjustment parameters are generated accordingly.

[0106] The processor converts the digital bias adjustment parameters into an analog voltage signal (i.e., power amplifier control data) via a digital-to-analog converter (DAC), and superimposes it onto the gate bias circuit of the RF power amplifier to perform dynamic bias control. At this time, the amplifier's operating point is pulled to the optimal position in real time, outputting an optimized bias power amplifier signal. Finally, the system continuously fine-tunes the bias voltage within the target saturation range, using a negative feedback loop to lock the output power, eliminating the effects of thermal drift, and ensuring that the amplifier stably and continuously outputs a high-energy RF waveform in a deeply saturated state, thus forming a saturated power RF carrier.

[0107] Preferably, step S4, which involves monitoring and transmitting the saturated power radio frequency carrier, includes:

[0108] The spectral density distribution of the saturated power radio frequency carrier is monitored to obtain the power spectral density monitoring results.

[0109] Based on the power spectral density monitoring results, the antenna feed parameters of the saturated power RF carrier are matched to obtain the enhanced power spectral density RF signal.

[0110] In one embodiment, the monitoring and transmission in step S4 are implemented as follows:

[0111] A small portion of the saturated power RF carrier is coupled out via a directional coupler at the end of the RF link as a sampling signal, which is then fed into a spectrum analysis circuit or a digital intermediate frequency receiver. The system performs a Fast Fourier Transform (FFT) on this sampled signal to calculate its energy distribution in the frequency domain, focusing on measuring the peak amplitude at the center frequency and the integrated power density within a set bandwidth. This generates a power spectral density monitoring result containing data on the measured bandwidth, center frequency power, and out-of-band spurious suppression ratio. This result is used to verify whether the signal has achieved the expected physical accumulation of energy within the narrow band.

[0112] Subsequently, the system dynamically adjusts the antenna front-end feed network based on the monitoring results. Due to the narrowing signal bandwidth and the power being at a saturated high level, the impedance matching point of the antenna feed system will drift. The system controls the variable capacitors or inductors in the tunable matching network to fine-tune the feed line standing wave ratio (VSWR) to achieve minimum reflection at the current narrowband frequency. For phased array antenna systems, the system also fine-tunes the phase weighting coefficients of each array element based on the monitored power density distribution to optimize beam directivity and ensure that energy is coupled into free space with maximum efficiency. After the above matching optimization, the electromagnetic wave radiated outward by the antenna, with an extremely high energy density per unit hertz, is the enhanced power spectral density radio frequency signal.

[0113] Therefore, the embodiments should be considered as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the application be incorporated into the invention.

[0114] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

Claims

1. A link-aware adaptive amplification method for digital signals in satellite communication, characterized in that, Includes the following steps: Step S1: Collect and analyze the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and perform a joint power boundary determination to form a limit saturation state word. Specifically, step S1 is as follows: The signal-to-noise ratio (SNR) data is compared with a preset communication sustaining threshold value to calculate the SNR margin value. Collect the current amplifier output power, measure the power saturation, and obtain the power saturation percentage; Using a preset threshold parameter table, a dual-parameter threshold determination is performed on the signal-to-noise ratio margin and power saturation percentage to generate the limit state determination result; Obtain the system working mode identifier, combine it with the limit state determination result to generate the state word encoding, and obtain the limit saturation state word; Step S2: Analyze the link quality loss value using the limit saturation state word; perform energy spectral density compensation conversion on the link quality loss value to obtain the bandwidth compression coefficient; perform equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain the rate reduction configuration parameters; Step S3: Calculate the energy loss in decibels based on the descent rate configuration parameters; determine the gain compensation coefficient based on the energy loss in decibels; convert the gain compensation coefficient into a control voltage adjustment amount, and synthesize the saturation bias voltage to form the saturation drive bias voltage value; Step S4: Generate a narrowband digital baseband signal based on the rate reduction configuration parameters, and apply pre-gain compensation by combining the saturation drive bias voltage value to form a gain-compensated intermediate frequency signal; optimize the power amplifier operating point control of the gain-compensated intermediate frequency signal to obtain a saturated power RF carrier. Monitoring and transmission of saturated power radio frequency carriers are performed to form an enhanced power spectral density radio frequency signal.

2. The link-aware adaptive amplification method for satellite communication digital signals according to claim 1, characterized in that, Step S2 includes: The state word of the limit saturation state word is parsed and conditionally triggered to obtain the compressed calculation activation flag; Based on the compression calculation activation flag and the preset communication maintenance threshold, a link quality difference analysis is performed to obtain the link quality loss value. Obtain the current symbol rate value, and perform a correlation calculation between symbol rate and bandwidth using the bandwidth compression factor to obtain the target symbol rate value; Hardware compatibility constraints are applied based on the target symbol rate value and a predefined symbol rate support table to obtain the rate reduction configuration parameters.

3. The link-aware adaptive amplification method for satellite communication digital signals according to claim 1, characterized in that, Step S2 involves performing spectral density compensation conversion on the link quality loss value, which includes: The link quality loss value is normalized by performing link loss decibel normalization to obtain the normalized loss decibel value. The theoretical bandwidth compression ratio is calculated based on the normalized loss decibel value. Map the theoretical bandwidth compression ratio to discrete compression ratios; Obtain the current modulation scheme, perform modulation scheme compatibility analysis based on discrete bit compression ratio, and determine the bandwidth compression coefficient.

4. The adaptive amplification method for satellite communication digital signals based on link awareness according to claim 1, characterized in that, Step S3 includes: Obtain the original symbol rate value, combine it with the rate reduction configuration parameters to calculate the bandwidth compression ratio, and obtain the actual bandwidth compression ratio; The energy loss in decibels is estimated and calculated based on the actual bandwidth compression ratio. The gain compensation coefficient is converted into circuit control parameters based on the gain and control voltage characteristic curve data of the amplifier to obtain the control voltage adjustment amount; Obtain the current operating voltage value of the amplifier and synthesize it with the control voltage adjustment amount to form a saturation drive bias voltage value.

5. The link-aware adaptive amplification method for satellite communication digital signals according to claim 1, characterized in that, Step S3, determining the gain compensation coefficient based on the energy loss in decibels, includes: Based on the energy loss in decibels, and combined with the preset bandwidth and gain compensation table, the bandwidth compression energy loss is calculated to obtain the theoretical gain compensation value. The power amplifier characteristic curve data is obtained by querying the theoretical gain compensation value. The nonlinearity compensation factor is calculated based on the power amplifier characteristic curve data and theoretical gain compensation value to obtain the nonlinearity correction factor; The theoretical gain compensation value is compensated using a nonlinear correction factor to form a gain compensation coefficient.

6. The link-aware adaptive amplification method for satellite communication digital signals according to claim 1, characterized in that, Step S4 involves generating a narrowband digital baseband signal based on the rate-drop configuration parameters, and applying pre-gain compensation by combining the saturation drive bias voltage value. Based on the down-rate configuration parameters, the symbol rate clock is adjusted to perform baseband data stream adjustment and generate a narrowband digital baseband signal; Narrowband signal envelope analysis is performed on narrowband digital baseband signals to obtain narrowband signal characteristic parameters; The gain control voltage value of the saturation drive bias voltage is converted by using the narrowband signal characteristic parameters to obtain the analog gain control signal; The compensation front-end circuit is selected based on the analog gain control signal, and a compensation circuit configuration instruction is generated. Dynamic gain adjustment is performed according to the compensation circuit configuration instructions to obtain the intermediate frequency gain adjustment signal; Obtain the target value for the gain setting, combine it with the intermediate frequency gain adjustment signal to perform gain locking and steady-state confirmation, and generate a gain lock status word; The intermediate frequency gain adjustment signal is verified and output based on the gain lock status word, and the intermediate frequency gain adjustment signal is used as the gain compensation intermediate frequency signal.

7. The link-aware adaptive amplification method for satellite communication digital signals according to claim 1, characterized in that, Step S4 involves optimizing the power amplifier operating point control of the gain-compensated intermediate frequency signal, including: The power amplifier saturation characteristics of the gain-compensated intermediate frequency signal are analyzed using the pre-stored power amplifier transfer characteristic curves to obtain the theoretical operating point data of the power amplifier. Based on the power amplifier's theoretical operating point data and bandwidth compression coefficient, the saturation region is located to obtain the target saturation range. Real-time power amplifier status monitoring is performed based on the saturation target range to obtain the power amplifier operating status deviation. Nonlinear distortion monitoring and compensation are performed on the power amplifier's operating state deviation to obtain the bias adjustment parameters; The bias adjustment parameters are converted into power amplifier control data and dynamic bias control processing is performed to obtain an optimized bias power amplifier signal. The operating point power amplifier is stabilized by optimizing the bias power amplifier signal and the saturation target range to form a saturated power RF carrier.

8. The adaptive amplification method for digital signals in satellite communication based on link awareness according to claim 1, characterized in that, Step S4, which involves monitoring and transmitting the saturated power radio frequency carrier, includes: The spectral density distribution of the saturated power radio frequency carrier is monitored to obtain the power spectral density monitoring results. Based on the power spectral density monitoring results, the antenna feed parameters of the saturated power RF carrier are matched to obtain the enhanced power spectral density RF signal.

9. A link-aware adaptive amplification system for satellite communication digital signals, characterized in that, For executing the link-aware adaptive amplification method for satellite communication digital signals as described in claim 1, the link-aware adaptive amplification system for satellite communication digital signals includes: The limit state detection module is used to collect and analyze the signal-to-noise ratio data fed back by the target terminal and the power detection data of the local transmitter, and perform a joint determination of the power boundary to form the limit saturation state word; The bandwidth compression calculation module is used to analyze the link quality loss value using the limit saturation state word; perform energy spectral density compensation conversion on the link quality loss value to obtain the bandwidth compression coefficient; and perform equal-energy bandwidth compression calculation based on the bandwidth compression coefficient to obtain the rate reduction configuration parameters. The gain compensation generation module is used to calculate the energy loss in decibels based on the descent rate configuration parameters; determine the gain compensation coefficient based on the energy loss in decibels; convert the gain compensation coefficient into a control voltage adjustment amount; and synthesize the saturation bias voltage to form the saturation drive bias voltage value. The high-density signal transmission module is used to generate a narrowband digital baseband signal based on the rate-down configuration parameters, and to perform pre-gain compensation application in combination with the saturation drive bias voltage value to form a gain-compensated intermediate frequency signal; the power amplifier operating point of the gain-compensated intermediate frequency signal is optimized and controlled to obtain a saturated power RF carrier; the saturated power RF carrier is monitored and transmitted to form an enhanced power spectral density RF signal.

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