An automatic gain control system for narrow dynamic range WR waveforms
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-23
- Publication Date
- 2026-08-11
AI Technical Summary
由于WR波形AGC段也有调制，导致相应WR波形幅度下，检波器的输出电压不够精准，从而限制了利用WR波形不同幅度对应的检波电压去控制不同衰减值的精确度
[0011]本发明相对现有技术具有突出的实质性特点和显著的进步，具体的说，本发明通过结合信道模块粗粒度AGC和数字模块细粒度AGC，解决了WR波形由于AGC段前10us的大幅度导致的假同步问题，同时扩展了WR波形的接收幅度范围，信道模块在实现粗粒度AGC时，在AGC段前10us内根据接收信号幅度完成射频30dBm的衰减，或根据数字模块控制指令完成中频40dBm的衰减，数字模块在实现细粒度AGC时，在AGC段前10us内根据信号能量给出信道模块中频衰减40dBm的控制指令，或者自身衰减12dBm。此外，当接收WR信号能量小于WR接收动态范围[-30dBm，-20dBm]的能量阈值时，数字模块控制信道模块减少5dBm的衰减，同时自身减少2dBm的衰减。在粗细粒度联合AGC下，将接收WR波形的幅度控制在可解调范围[-30dBm，-20dBm]。本发明设计的粗粒度和细粒度联和AGC方案，不仅解决了WR波形由于AGC段前10us的大幅度导致的假同步问题，而且成功将WR波形的接收幅度范围从[-30dBm，-20dBm]扩展到了[-90dBm，0dBm]。
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Figure CN122553866A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of WR waveform control, and in particular to an automatic gain control system for WR waveforms with narrow dynamic range. Background Technology
[0002] The ultra-shortwave power amplifier unit of the self-developed wireless communication integrated processing terminal needs to be adapted to a brand-new WR (a type of write signal) waveform.
[0003] WR waveform time slots as follows Figure 3 As shown, the duration of the AGC (Automatic Gain Control) segment and the synchronization segment is 60µs, while the data segment duration is 1.2ms. Because the WR waveform is also modulated in the AGC segment, the detector's output voltage is not precise enough at the corresponding WR waveform amplitude, thus limiting the accuracy of controlling different attenuation values using the detector voltage corresponding to different WR waveform amplitudes. Furthermore, the WR waveform has a special characteristic: when receiving large signals, if the WR waveform amplitude does not undergo proper attenuation for approximately 10µs in the AGC segment, false synchronization will occur. In this case, the synchronization indicator appears in the AGC segment, causing the subsequent synchronization segment to be received as a data segment, resulting in errors during data decoding. Summary of the Invention
[0004] To address the problems existing in the background art, this invention proposes an automatic gain control system for narrow dynamic range WR waveforms.
[0005] An automatic gain control system for narrow dynamic range (WR) waveforms includes a channel module and a digital module. The channel module includes a radio frequency (RF) signal processing module, a first intermediate frequency (IF) signal processing module, and a coarse-grained AGC module. The input of the RF signal processing module is connected to an antenna for receiving RF signals, and its output is connected to the input of the first IF signal processing module. The coarse-grained AGC module controls the connection between the RF signal processing module and the first IF signal processing module. The digital module includes a second IF signal processing module, an ADC sampling module, and a fine-grained AGC module. The input of the second IF signal processing module is connected to the output of the first IF signal processing module, and its output is connected to a soft terminal block via the ADC sampling module. The fine-grained AGC module controls the connection between the second IF signal processing module and the coarse-grained AGC module.
[0006] Based on the above, the radio frequency signal processing module includes a radio frequency signal attenuator, the first intermediate frequency signal processing module includes a first intermediate frequency signal attenuator, and the coarse-grained AGC module controls and connects the radio frequency signal attenuator and the first intermediate frequency signal attenuator respectively; the second intermediate frequency signal processing module includes a second intermediate frequency signal attenuator, and the fine-grained AGC module controls and connects the second intermediate frequency signal attenuator.
[0007] Based on the above, the channel module segments the received amplitude (-90dBm, 0dBm) of the WR waveform: when the received signal amplitude is in the range of [-45dBm, 0dBm], the RF signal attenuator is activated, attenuating by 30dBm each time, and the first IF signal attenuator is activated simultaneously, attenuating by 40dBm each time, with the number of attenuation cycles controlled by the digital module; when the received signal amplitude is in the range of (-75dBm, -45dBm], only the first IF signal attenuator is activated for 40dBm, with the number of attenuation cycles controlled by the digital module; when the received signal amplitude is in the range of (-90dBm, -75dBm], the channel module does not activate attenuation.
[0008] Based on the above, the digital module detects the peak value of the AGC segment of the WR waveform every 2.5us. After the RF signal is attenuated by the channel module and the digital module, when the signal amplitude is attenuated to less than the lower boundary point of the peak value corresponding to the AGC segment, the attenuation is reduced by 2dBm. At the same time, the channel module is instructed to reduce the attenuation by 5dBm. This adjustment is repeated until the signal peak value enters the dynamic range of the WR waveform.
[0009] Based on the above, the inherent gain of the channel module is 70dBm, and the inherent attenuation of the digital module is 6dBm.
[0010] Based on the above, the dynamic range of the WR waveform is [-30dBm, -20dBm].
[0011] This invention possesses significant substantive features and substantial advancements compared to existing technologies. Specifically, by combining coarse-grained AGC of the channel module and fine-grained AGC of the digital module, this invention solves the false synchronization problem of the WR waveform caused by the large amplitude in the first 10µs of the AGC segment. Simultaneously, it expands the received amplitude range of the WR waveform. When implementing coarse-grained AGC, the channel module performs a 30dBm attenuation of the radio frequency within the first 10µs of the AGC segment based on the received signal amplitude, or a 40dBm attenuation of the intermediate frequency (IF) based on the control command of the digital module. When implementing fine-grained AGC, the digital module provides a control command for 40dBm IF attenuation of the channel module within the first 10µs of the AGC segment based on the signal energy, or performs a 12dBm attenuation itself. Furthermore, when the received WR signal energy is less than the energy threshold of the WR received dynamic range [-30dBm, -20dBm], the digital module controls the channel module to reduce attenuation by 5dBm, while simultaneously reducing its own attenuation by 2dBm. Under the combined coarse and fine granular AGC, the amplitude of the received WR waveform is controlled within the demodulation range [-30dBm, -20dBm]. The coarse and fine granular combined AGC scheme designed in this invention not only solves the false synchronization problem of the WR waveform caused by the large amplitude in the first 10µs of the AGC segment, but also successfully extends the received amplitude range of the WR waveform from [-30dBm, -20dBm] to [-90dBm, 0dBm]. Attached Figure Description
[0012] Figure 1 This is a schematic block diagram of the structure of the present invention.
[0013] Figure 2 This is a schematic diagram of the WR waveform time slot of the present invention.
[0014] Figure 3 This is the coarse-grained AGC flowchart of the present invention.
[0015] Figure 4 This is the fine-grained AGC flowchart of the present invention. Detailed Implementation
[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0017] like Figure 1As shown, an automatic gain control system for narrow dynamic range (WR) waveforms includes a channel module and a digital module. The channel module has an inherent gain of 70 dBm, and its coarse-grained AGC (Automatic Gain Control) section provides two levels of attenuation control: radio frequency (RF) attenuation and intermediate frequency (IF) attenuation. The channel module includes an RF signal processing module, a first IF signal processing module, and a coarse-grained AGC module. The input of the RF signal processing module is connected to an antenna for receiving RF signals, and its output is connected to the input of the first IF signal processing module. The coarse-grained AGC module controls the connections between the RF signal processing module and the first IF signal processing module. The RF attenuation of the channel module is implemented by the RF signal processing module, and the IF attenuation is implemented by the first IF signal processing module.
[0018] The digital module includes a second intermediate frequency (IF) signal processing module, an ADC sampling module, and a fine-grained AGC module. The input of the second IF signal processing module is connected to the output of the first IF signal processing module, and the output of the second IF signal processing module is connected to a software-defined radio terminal (Software Radio Terminal) through the ADC sampling module. The fine-grained AGC module controls the connection between the second IF signal processing module and the coarse-grained AGC module. The fine-grained AGC part of the digital module calculates the peak value (Energy_Max) and average value (Energy_Avg) using the I-channel and Q-channel data acquired by the IF ADC, then controls its own attenuation, and simultaneously sends a command signal to the channel module, thereby controlling the IF attenuation of the channel module.
[0019] Specifically, the radio frequency (RF) signal processing module includes an RF signal attenuator, the first intermediate frequency (IF) signal processing module includes a first IF signal attenuator, and the coarse-grained AGC module controls and connects to both the RF signal attenuator and the first IF signal attenuator; the second IF signal processing module includes a second IF signal attenuator, and the fine-grained AGC module controls and connects to the second IF signal attenuator. In practice, the channel module also includes an RF detector, an RF switch, etc. The coarse-grained AGC module of the channel module controls the switching of the RF switch based on the voltage value of the RF detector, thereby selecting whether to activate RF attenuation. The coarse-grained AGC module also receives control commands from the digital module to control IF attenuation.
[0020] WR waveform time slots as follows Figure 2As shown, the duration of the AGC segment and the synchronization segment is 60µs, and the data segment duration is 1.2ms. Because the WR waveform is also modulated in the AGC segment, the detector's output voltage is not precise enough at the corresponding WR waveform amplitude, thus limiting the accuracy of controlling different attenuation values using the detector voltage corresponding to different WR waveform amplitudes. Furthermore, the WR waveform has a special characteristic: when receiving large signals, if the WR waveform amplitude is not properly attenuated within approximately 10µs of the AGC segment, false synchronization will occur. In this case, the synchronization indicator appears in the AGC segment, causing the subsequent synchronization segment to be received as a data segment, resulting in errors during data decoding. The purpose of this embodiment is to use appropriate attenuation (channel module attenuation combined with digital module attenuation) within the first 10µs of the AGC segment to attenuate the received signal amplitude to a suitable range to avoid false synchronization. Then, in the remaining AGC segment, the received signal amplitude is adjusted to within the received dynamic range of the WR waveform [-30dBm, -20dBm] to ensure correct demodulation of the WR waveform.
[0021] In this embodiment, gain control includes coarse-grained AGC for the signal module and fine-grained AGC for the digital module, specifically: Channel module coarse-grained AGC To address the unique characteristics of the WR waveform, the channel module segments the received amplitude (-90dBm, 0dBm) to resolve the issue of inaccurate intermediate frequency (IF) detection under varying received signal amplitudes. Simultaneously, to attenuate the WR signal within the (-90dBm, 0dBm) range to an amplitude that prevents false synchronization within 10µs, the channel module activates the RF attenuator when the received signal amplitude is in the range [-45dBm, 0dBm] (RF detection voltage greater than 2.8V), attenuating by 30dBm each time, and simultaneously activates IF attenuation, attenuating by 40dBm each time; the number of attenuation cycles is controlled by the digital module. Furthermore, when the received signal amplitude is in the range (-75dBm, -45dBm), the channel module only activates IF attenuation for 40dBm, with the number of attenuation cycles controlled by the digital module. When the received signal amplitude is in the range (-90dBm, -75dBm), the channel module does not activate attenuation.
[0022] The specific process of AGC for the channel module is as follows: Figure 3As shown, when controlling RF attenuation, the channel module first acquires the RF detection voltage, then checks if the synchronization signal is 1. When the synchronization signal is 0, it checks if the RF detection voltage is greater than or equal to 2.8V (RF control voltage). If the voltage is greater than or equal to 2.8V, it initiates RF attenuation of 30dBm. This 30dBm attenuation is maintained until the synchronization of this frame of data ends (synchronization indicator signal is 0), then it waits for the synchronization signal to become 1. The intermediate frequency (IF) attenuation of the channel module is controlled by the digital module. When the digital module detects that the signal energy Energy_Max >= Energy_Max_Satu (the threshold for channel-controlled IF attenuation, slightly higher than Energy_Max_High), it instructs the channel IF to attenuate by 40dBm. When the channel module detects that the signal energy Energy_Max < Energy_Max_Low, the digital module instructs the channel module to reduce the IF attenuation by 5dBm. The main purpose is to use a fixed attenuation value to cover the receiving amplitude range of [-90dBm, 0dBm] in the case of false synchronization and insufficient RF detection voltage accuracy.
[0023] For example, when the received signal amplitude is -20dBm (large signal), the channel module's RF attenuation is 30dBm, the intermediate frequency module's attenuation is 40dBm, and the channel module's inherent gain is 70dBm. Therefore, the signal amplitude supplied to the digital module is -20dBm. With the digital module's inherent 6dBm attenuation, the received WR waveform amplitude is -26dBm, within its dynamic range of [-30dBm, -20dBm]. When the received signal amplitude is -50dBm (intermediate signal), the channel module's RF attenuation is uncontrolled, the intermediate frequency module's attenuation is 40dBm, and the channel module's inherent gain is 70dBm. Therefore, the signal amplitude supplied to the digital module is -20dBm. With the digital module's inherent 6dBm attenuation, the received WR waveform amplitude is -26dBm, within its dynamic range of [-30dBm, -20dBm]. When the received signal amplitude is -80dBm (small signal), the channel module's RF attenuation is not controlled, and the intermediate frequency module is also not controlled. The channel module has an inherent gain of 70dBm, so the signal amplitude supplied to the digital module is -10dBm. At this time, the digital module has an inherent attenuation of 6dBm, and the received WR waveform amplitude is -16dBm. The digital module will then increase the attenuation by 12dBm, and the adjusted WR waveform signal amplitude is -28dBm, within its dynamic range of [-30dBm, -20dBm].
[0024] Digital module fine-grained AGC The attenuation value of the digital module's attenuator, specifically the second intermediate frequency signal attenuator, is adjustable within a range of 0dBm to 31.5dBm, with a minimum adjustable step of 0.5dBm. In practical applications, the default attenuation value of this attenuator is 6dBm, adjusted in 12dBm increments. This ensures that the WR waveform, after being processed by the channel module's AGC, is further adjusted by the digital module's AGC to fit within the dynamic range of the WR waveform [-30dBm, -20dBm]. Furthermore, the upper and lower boundary points (Energy_Max_Low, Energy_Max_High) of the corresponding peak value in the AGC segment are tested at the dynamic upper and lower edges of the WR waveform, while simultaneously detecting the real-time peak value Energy_Max. Correspondingly, the upper and lower boundary points (Energy_Avg_Low, Energy_Avg_High) of the mean value are also tested, while simultaneously detecting the real-time mean value Energy_Avg. These boundary points are used for subsequent peak and mean value determination in the AGC segment.
[0025] Fine-grained AGC in digital modules, such as Figure 4 As shown, the state machine of the control flow has a total of three states.
[0026] The initial default state is AGC_HOLD. In this state, it checks whether there is a synchronization indication. If there is, it maintains the existing decay value and keeps the state unchanged. If not, it jumps to the AGC_STARTUP state and starts AGC.
[0027] In the AGC_STARTUP state, when SYNC is 1, it directly jumps to the AGC_HOLD state. When SYNC is 0, every 2.5us delay (in actual measurements, after the attenuator attenuation value changes, the WR waveform data acquired by the AD will have a delay of about 2us), the maximum peak value Energy_Max and the average value Energy_Avg of the AGC segment of the WR waveform within 2.5us are detected. When Energy_Max >= Energy_Max_Satu (the threshold value of the channel start-up control intermediate frequency, slightly higher than Energy_Max_High), an instruction is given to attenuate the channel intermediate frequency by 40dBm; when Energy_Max_High < Energy_Max < Energy_Max_Satu, the digital module increases the attenuation by 12dBm; when 0 < Energy_Max < Energy_Max_Low, the digital module reduces the attenuation by 2dBm (up to a maximum reduction to the default attenuation of 6dBm), and an instruction is given to reduce the attenuation of the channel intermediate frequency by 5dBm. When Energy_Max_Low <= Energy_Max <= Energy_Max_High, it indicates that the peak value of the AGC segment of the WR waveform has entered the AGC locking range. At this time, if Energy_Avg_Low <= Energy_Avg <= Energy_Avg_High, it jumps to the AGC_LOCK state. Otherwise, it still enters the AGC_STARUP state.
[0028] In the AGC_LOCK state, when SYNC is 1, it directly jumps to the AGC_HOLD state. When SYNC is 0, in the AGC_STARTUP state, every 2.5µs delay, the maximum peak value Energy_Max and the average value Energy_Avg of the WR waveform AGC segment within that 2.5µs period are detected. When Energy_Max >= Energy_Max_Satu, an instruction is given to attenuate the channel intermediate frequency by 40dBm, and it jumps to the AGC_STARTUP state; when Energy_Max_High < Energy_Max < Energy_Max_Satu, the digital module restores the default 6dBm attenuation, and it jumps to the AGC_STARUP state; when Energy_Max_Low < Energy_Max < Energy_Max_High, the digital module maintains the current attenuation value and remains in the AGC_LOCK state.
[0029] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
Claims
1. An automatic gain control system for narrow dynamic range WR waveforms, characterized in that: The system includes a channel module and a digital module. The channel module comprises a radio frequency (RF) signal processing module, a first intermediate frequency (IF) signal processing module, and a coarse-grained AGC module. The input of the RF signal processing module is connected to an antenna for receiving RF signals, and the output of the RF signal processing module is connected to the input of the first IF signal processing module. The coarse-grained AGC module controls the connection between the RF signal processing module and the first IF signal processing module. The digital module comprises a second IF signal processing module, an ADC sampling module, and a fine-grained AGC module. The input of the second IF signal processing module is connected to the output of the first IF signal processing module, and the output of the second IF signal processing module is connected to a soft terminal via the ADC sampling module. The fine-grained AGC module controls the connection between the second IF signal processing module and the coarse-grained AGC module.
2. The automatic gain control system for narrow dynamic range WR waveforms according to claim 1, characterized in that: The radio frequency signal processing module includes a radio frequency signal attenuator, the first intermediate frequency signal processing module includes a first intermediate frequency signal attenuator, and the coarse-grained AGC module controls and connects the radio frequency signal attenuator and the first intermediate frequency signal attenuator respectively; the second intermediate frequency signal processing module includes a second intermediate frequency signal attenuator, and the fine-grained AGC module controls and connects the second intermediate frequency signal attenuator.
3. The automatic gain control system for narrow dynamic range WR waveforms according to claim 2, characterized in that: The channel module segments the received amplitude (-90dBm, 0dBm) of the WR waveform: when the received signal amplitude is in the range of [-45dBm, 0dBm], the RF signal attenuator is activated, attenuating by 30dBm each time, and the first IF signal attenuator is activated simultaneously, attenuating by 40dBm each time, with the number of attenuation cycles controlled by the digital module; when the received signal amplitude is in the range of (-75dBm, -45dBm], only the first IF signal attenuator is activated for 40dBm, with the number of attenuation cycles controlled by the digital module; when the received signal amplitude is in the range of (-90dBm, -75dBm], the channel module does not activate attenuation.
4. The automatic gain control system for narrow dynamic range WR waveforms according to claim 2, characterized in that: Every 2.5us, the digital module detects the peak value of the AGC segment of the WR waveform within 2.5us. After the RF signal is attenuated by the channel module and the digital module, when the signal amplitude is attenuated to less than the lower boundary point of the corresponding peak value of the AGC segment, the attenuation is reduced by 2dBm. At the same time, the channel module is instructed to reduce the attenuation by 5dBm. This adjustment is repeated until the signal peak value enters the dynamic range of the WR waveform.
5. The automatic gain control system for narrow dynamic range WR waveforms according to claim 1, characterized in that: The channel module has an inherent gain of 70dBm, and the digital module has an inherent attenuation of 6dBm.
6. The automatic gain control system for narrow dynamic range WR waveforms according to claim 4, characterized in that: The dynamic range of the WR waveform is [-30dBm, -20dBm].