Automatic gain control system and method based on radio frequency envelope detection, and receiver

Abstract

The invention provides an automatic gain control system and method based on radio frequency envelope detection, and a receiver. The bias end of an LNA is connected with an automatic gain control module; an envelope detection circuit is also connected between the output end of the LNA and the frequency mixer, and the envelope detection circuit is connected with an automatic gain control module; the detection module is used for outputting a preset level saturation indication signal to the automatic gain control module when an input signal which comes from the output end of the LNA and is greater than preset power is detected; the control end of the VGA is connected with the automatic gain control module; the output end of the ADC is connected with the automatic gain control module; the automatic gain control module performs automatic adjustment of receiver link gain. The fast envelope detection provides extra information, the automatic gain control response speed of the system is improved, the circuit design is simple, the power consumption is smaller, only a smaller chip layout area is occupied, and the cost is lower.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to an automatic gain control system, method and receiver based on radio frequency envelope detection. Background Art

[0002] In wireless communication systems, the ability of received signals to resist interference is a critical metric. Currently, the primary approach used is to use fast AGC to prevent saturation of the receiving channel under strong interference signals, ensuring normal operation of the receiving channel under strong interference signals.

[0003] Common fast AGC methods include using RF filters for digital power statistics and reporting individual analog branch power. While these methods offer relatively accurate interference power detection, they are costly and time-consuming. When a large blocking signal appears at the antenna port, the long detection time can saturate the receiving channel, preventing signal demodulation. This can also lead to packet loss or temporary service interruptions.

[0004] Therefore, a new automatic gain control scheme based on RF envelope detection is needed. Summary of the Invention

[0005] In view of this, embodiments of the present disclosure provide an automatic gain control system, method, and receiver based on radio frequency envelope detection.

[0006] The embodiments of this specification provide the following technical solutions:

[0007] The embodiments of this specification provide an automatic gain control system based on radio frequency envelope detection, including:

[0008] Main link circuit, envelope detection circuit, automatic gain control module;

[0009] The main link circuit is provided with a low noise amplifier, a mixer, a low pass filter, a variable gain amplifier, and an analog-to-digital converter in sequence;

[0010] An input terminal of the low noise amplifier is connected to the antenna, and an output terminal of the low noise amplifier is connected to an input terminal of the mixer;

[0011] Connection between the bias terminal of the low noise amplifier and the automatic gain control module;

[0012] The output end of the low noise amplifier is also connected to the envelope detection circuit, and the envelope detection circuit is connected to the automatic gain control module;

[0013] The envelope detection circuit sets a reporting threshold for outputting a preset level saturation indication signal to the automatic gain control module when an input signal greater than a preset power is detected from the output end of the low noise amplifier;

[0014] The control end of the variable gain amplifier is connected to the automatic gain control module; the output end of the analog-to-digital converter is connected to the automatic gain control module;

[0015] The automatic gain control module is used to receive the power reporting information of the main link analog-to-digital converter or the power indication information reported by the envelope detection, and when receiving the preset level saturation indication signal, it is sent to the control end of the variable gain amplifier or the bias end of the low noise amplifier according to the pre-set gain control gear.

[0016] The embodiment of this specification also provides an automatic gain control method based on radio frequency envelope detection, comprising: when the envelope detection circuit detects an input signal from the output end of a low noise amplifier and having a power greater than a preset power, outputting a preset level saturation indication signal to the automatic gain control module; wherein the envelope detection circuit sets a reporting threshold;

[0017] The automatic gain control module receives the power reporting information of the main link analog-to-digital converter or the power indication information reported by the envelope detection circuit. When it receives the preset level saturation indication signal, it sends it to the control end of the variable gain amplifier and the bias end of the low noise amplifier according to the pre-set gain control gear.

[0018] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0019] This application is based on the main link circuit, with an envelope detection circuit placed after the LNA and before the mixer. By integrating envelope detection power information and main ADC output power detection information, it automatically controls the receiver link gain, offering the advantages of fast gain control and low cost. Compared to traditional automatic gain controllers that perform multiple gain adjustments based solely on power statistics from main ADC or auxADC sampling data, fast envelope detection provides additional information, improving the system's automatic gain control response speed. It also simplifies the circuit design, consumes less power, occupies a smaller chip layout area, and is less expensive. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 This is a schematic diagram of the automatic gain control solution in the prior art. Figure 1 ;

[0022] Figure 2 This is a schematic diagram of the automatic gain control solution in the prior art. Figure 2 ;

[0023] Figure 3 is a schematic diagram of a fast automatic gain control architecture in an embodiment of this specification;

[0024] Figure 4 It is a schematic diagram of a fast automatic gain control method in an embodiment of this specification.

[0025] Figure 5 It is a flow chart of the fast automatic gain control method in the embodiment of this specification. DETAILED DESCRIPTION

[0026] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0027] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0028] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0029] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0030] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples, however, one skilled in the art will appreciate that the examples can be practiced without these specific details.

[0031] The technical terms in the embodiments of this specification are explained as follows:

[0032] Envelope detection: The process of demodulating a low-frequency signal from an amplitude modulated signal is the demodulation of amplitude modulation.

[0033] AGC (Automatic Gain Control) refers to an automatic control method that automatically adjusts the gain of the amplifier circuit according to the strength of the signal.

[0034] LNA (Low Noise Amplifier) is an active RF device that plays a key role in the RF signal chain.

[0035] LPF (Low Pass Filter) is an electronic filter that can separate high-frequency signals from low-frequency signals, thereby changing the frequency characteristics of the signal.

[0036] A VGA (Variable Gain Amplifier) changes the gain of a signal by adjusting its internal circuit parameters, thereby achieving controllable regulation of signal strength.

[0037] ADC (Analog-to-Digital Converter) is an electronic device that converts analog signals into digital signals.

[0038] In wireless communication systems, the ability of received signals to resist interference is a critical metric. Currently, the primary approach is to use fast AGC to prevent saturation of the receiving channel under strong interference signals, ensuring normal operation of the receiving channel under strong interference signals.

[0039] There are currently multiple solutions for fast AGC. Common solutions include using RF filters for digital power statistics and reporting individual analog branch power statistics. While these solutions offer the advantage of relatively accurate interference power detection, they also suffer from high costs and long detection times. When a large blocking signal appears at the antenna port, the long detection time can lead to saturation of the receiving channel and inability to demodulate the signal properly. This can also cause packet loss or temporary service interruptions.

[0040] like Figure 1As shown, Solution 1 uses RF filters, which is common in the cellular communications field. In the entire solution design, only the main link ADC receives and transmits the signal while passing the power information to the automatic gain control module for progressive power control. Because the statistics of the entire link are set at the last stage, it cannot quickly respond to the gain protection control when the interference signal is input, nor can it quickly control the gain of high-power fluctuating signals. Therefore, in order to shield the external abnormal large signal interference, it is necessary to add an in-band filter at the RF input end. However, this increases the design cost and deteriorates the link noise figure.

[0041] like Figure 2 As shown, Solution 2 uses a separate analog branch, which is common in wireless short-range communications. An Aux ADC is added to count out-of-band interference signals. Although accurate out-of-band signal power can be viewed in the digital domain, the cost is the addition of an ADC for each channel. Uploading the Aux ADC to the AGC controller requires multiple bits of digital-to-analog interface overhead, resulting in high costs.

[0042] Based on this, the embodiments of this specification propose a new, fast, and low-cost automatic gain control solution based on RF envelope detection. This solution utilizes analog peak detection and threshold configuration after power-on. When the power of the external interference signal reaches the analog detection threshold, a high-level saturation indication signal is output. Upon receiving the saturation indication signal, the AGC (Automatic Gain Control) module in the receive link rapidly adjusts the automatic gain control module to ensure uncompressed and operational receive channel operation. This solution features a simple circuit design, fast automatic control response, lower power consumption, and a smaller chip footprint, resulting in lower costs.

[0043] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0044] The embodiment of this specification sets up an automatic gain control system based on radio frequency envelope detection, including a main link circuit, an envelope detection circuit and an automatic gain control module. Figure 3 For example, the main link circuit is equipped with LNA, mixer, LPF, VGA, and ADC in sequence. The input of LNA is connected to the antenna, and the output of LNA is connected to the input of mixer. The bias terminal of LNA is connected to AGC. The output of LNA is also connected to envelope detection circuit, and the envelope detection circuit is connected to AGC.

[0045] The envelope detection circuit sets a reporting threshold for outputting a high-level saturation indication signal to the AGC when an input signal greater than a preset power is detected from the output end of the LNA;

[0046] The control end of the VGA is connected to the automatic gain control module; the output end of the ADC is connected to the AGC;

[0047] The AGC receives power information reported by the main link ADC or the power indication reported by the envelope detector. Upon receiving a high-level saturation indication signal, it sends it to the VGA control terminal or the LNA bias terminal based on the preset gain control level. This results in a simple circuit design, fast automatic control response, lower power consumption, and a smaller chip footprint, resulting in lower costs.

[0048] It should be noted that the above method is used if the output signal of the envelope detection circuit is very clean.

[0049] Radio frequency signals are usually subject to various interferences, which may cause the output signal of the envelope detection circuit to have certain noise. Or the application scenario requires extremely high response speed of AGC, such as Figure 3 For example, a digital filter is provided between the envelope detection circuit and the AGC to filter the saturation indication signal.

[0050] Specifically, the architecture employs analog peak detection combined with digital filtering. After the analog detector is powered on, a detection threshold is configured. When the power of the external interference signal reaches the analog detection threshold, a high-level saturation indication signal is output to the digital filter. The digital filter filters the saturation indication signal, ensuring that the AGC controller is not repeatedly activated by the saturation indication signal. Upon receiving the saturation indication signal, the AGC quickly adjusts the automatic gain control module on the receive link to ensure that the receive channel is not compressed and can operate normally. This results in a simple circuit design, fast automatic control response, lower power consumption, and a smaller chip layout area, resulting in lower costs.

[0051] like Figure 3 As shown, the embodiment of this specification includes a typical receiving link (ie, main link) module and an innovative fast power indication module (such as an envelope detection circuit, a digital filter, and an automatic gain control module).

[0052] Specifically, the receiving chain includes LNA (low noise amplifier), mixer, LPF (filter), VGA (amplifier), as well as intermediate frequency ADC and digital demodulator.

[0053] An input end of the LNA is connected to the antenna, and an output end of the LNA is connected to an input end of the mixer.

[0054] Connection between the bias terminal of the LNA and the automatic gain control module.

[0055] The output of the LNA is also connected to an envelope detection circuit, which is in turn connected to a digital filter and an automatic gain control module;

[0056] The envelope detection circuit sets a reporting threshold, which allows it to output a preset level saturation indication signal to the digital filter when it detects an input signal from the LNA output that exceeds a preset power level. Specifically, the RF signal from the LNA is fed into the envelope detection circuit, which detects amplitude variations in the RF signal and extracts the signal's envelope information, reflecting power variations. When the detected signal power exceeds the preset threshold, the envelope detection circuit outputs a high-level saturation indication signal for further processing by the digital filter.

[0057] The digital filter is used to receive a preset level saturation indication signal and filter out interference burrs, and report the processed digital signal to the automatic gain control module to ensure that the automatic gain control module is not frequently and repeatedly activated by the saturation indication signal;

[0058] The control end of the VGA is connected to the automatic gain control module; the output end of the ADC is connected to the automatic gain control module;

[0059] The automatic gain control module is used to receive the power reporting information of the main link ADC or the power indication information reported by the digital filter, and when receiving the processed digital signal, it is sent to the control end of the VGA or the bias end of the LNA according to the preset gain control gear.

[0060] Among them, the fast power detection module can set an appropriate power detection threshold according to the application scenario for reporting high-power input signals to assist the receiving link (i.e., the main link) in performing fast power control, and the fast envelope detection indication has a response time of hundreds of nanoseconds.

[0061] Set the appropriate detection reporting threshold of the envelope detector shown in the figure according to the application scenario. The envelope detection reporting threshold can be set in steps of up to 1 dB according to the design of different threshold values and accuracy.

[0062] The fast automatic gain control module will simultaneously receive the power reporting information of the main link ADC and the power indication information reported by the fast envelope detection (via the digital filter), among which the fast envelope detection reports faster and has a higher priority.

[0063] When the fast envelope detection module detects an input signal greater than the power threshold, it reports a power overlimit indication signal, which is then filtered out by a digital filter circuit to remove interference glitches and then reported to the fast automatic gain control module.

[0064] After receiving the envelope detection power reporting indication, the fast automatic gain control module will directly send it to each module of the receiving link for rapid control according to the pre-set gain control gear, without the need for small gear step adjustment, thereby improving the AGC response speed of the entire link.

[0065] Since the response time of the analog detection and digital filter is very fast, a saturation indication report of the order of hundreds of nanoseconds can be achieved without deteriorating the noise of the receiving link.

[0066] In some embodiments, when the fast automatic gain control module does not receive an envelope detection indication report, it performs fine power adjustment based on the power information reported by the ADC to meet higher precision system requirements.

[0067] The RF envelope detection circuit in this embodiment directly detects the RF signal envelope. Positioned after the low-noise amplifier and before the mixer, it implements fast power detection in the analog domain. Compared to traditional IF detection circuits, it offers shorter latency and faster detection speeds. The envelope detection circuit also adapts to power thresholds, meeting the requirements for fast power detection thresholds in various application scenarios.

[0068] The digital filter is located between the envelope detection circuit and the automatic gain control module. It smoothes the output of the envelope detection circuit and filters out burrs and jitter. This prevents sudden interference and power detection jitter in scenarios where the power is near the detection threshold. It ensures that the automatic gain control module is not frequently and repeatedly activated by the saturation indication signal directly output by the envelope detection circuit, thereby increasing the robustness of the automatic gain control scheme.

[0069] The automatic gain control module automatically adjusts the receiver link gain by integrating envelope detection power information and main ADC output power detection information. This offers the advantages of fast gain control and low cost. Compared to traditional automatic gain control modules that perform multiple gain adjustments based solely on power statistics from the main ADC or auxADC sampled data, fast envelope detection and digital filters provide additional information, improving the system's automatic gain control response speed. The automatic gain control module additionally utilizes power level information output by the envelope detector and digital filter, and based on this power level information, determines whether a rapid gain adjustment of the RF circuit is necessary.

[0070] In some embodiments, the envelope detection circuit sets multiple thresholds, each threshold sets corresponding upper and lower intervals, and supports multi-channel parallel operation; the automatic gain control module performs multi-segment power gain rapid response control according to the multiple power threshold indications reported by the envelope detection.

[0071] In combination with the above embodiments, multiple threshold values are set for envelope detection, such as setting three thresholds of high, medium and low. Each threshold can set upper and lower ranges to support multiple channels working in parallel; the high, medium and low thresholds can be set according to the application scenario. For example, a scenario with a lot of interference but weak interference can set a medium and low threshold, and a scenario with little interference but strong interference can set a high threshold.

[0072] The fast automatic gain control module will perform more precise multi-segment power gain fast response control based on multiple power threshold indications reported by envelope detection.

[0073] When the envelope detection circuit is configured with multiple thresholds, no additional circuit design is required. Since the reporting digital interface is multi-channel and parallel, the number of digital filters needs to be increased accordingly, but this has little impact on the circuit area and power consumption.

[0074] In some embodiments, the envelope detection circuit is configured with multiple thresholds, and each threshold is regulated separately according to the priority corresponding to each threshold.

[0075] Because the fast envelope detection circuit can set multiple thresholds, it can perform priority sequence threshold control for multiple scenarios and complex signals, making the application more flexible and safe.

[0076] For example, the low threshold L, medium threshold M, and high threshold H are set according to the application scenario. The envelope detection circuit detects the power of the RF signal in real time and performs threshold comparison. If the signal power exceeds multiple thresholds simultaneously, the high threshold is prioritized, and the automatic gain control module automatically adjusts the receiver link gain.

[0077] In some embodiments, the envelope detection circuit is provided with multiple thresholds, and different detection level branches are respectively connected to independent digital filters.

[0078] When the envelope detection circuit is used for multiple threshold settings, no additional circuit design is required. Since the reporting digital interface is multi-channel parallel, the number of digital filters needs to be increased accordingly to achieve independent digital filters for connecting branches with different detection levels, but this has little impact on the circuit area and power consumption.

[0079] In some embodiments, the automatic gain control module is further configured to perform power adjustment according to power information reported by the ADC when no envelope detection indication reporting signal is received.

[0080] Specifically, if Figure 3 As shown in the figure, when the fast automatic gain control module does not receive an envelope detection indication, it performs fine power adjustments based on the power information reported by the ADC, such as through small step size adjustments and closed-loop feedback mechanisms to meet higher system precision requirements. This mode, combined with fast automatic gain control, enables the entire AGC system to quickly respond to burst signals while finely adjusting signal power, maintaining excellent performance in various scenarios.

[0081] In some embodiments, the gain control levels preset in the automatic gain control module are associated with different signal power ranges so that the preset gain control levels can be directly sent to each connected module in the receiving link for rapid control.

[0082] After receiving the envelope detection power reporting indication, the fast automatic gain control module will directly send it to each module of the receiving link for rapid control according to the pre-set gain control gear, without the need for small gear step adjustment, thereby improving the AGC response speed of the entire link.

[0083] The automatic gain control module determines whether a rapid gain adjustment of the RF circuit is required based on the power level information.

[0084] After a quick gain adjustment, the automatic gain control module integrates the power information statistically collected by the main ADC to perform a second fine-tuning of the RF circuit.

[0085] In combination with the above embodiments, this specification also provides a fast and low-cost automatic gain control method based on radio frequency envelope detection, such as Figure 5 The method includes steps S501 and S502. Step S501: When the envelope detection circuit detects an input signal from the output end of the low-noise amplifier that is greater than a preset power, it outputs a preset level saturation indication signal to the automatic gain control module; wherein the envelope detection circuit sets a reporting threshold. Step S502: The automatic gain control module receives the power reporting information of the main link analog-to-digital converter or the power indication information reported by the envelope detection circuit, and when receiving the preset level saturation indication signal, sends it to the control end of the variable gain amplifier and the bias end of the low-noise amplifier according to the preset gain control gear.

[0086] In some embodiments, it also includes: a digital filter receives a preset level saturation indication signal and performs smoothing, burr and jitter filtering, and reports the processed digital signal to the automatic gain control module to ensure that the automatic gain control module is not frequently and repeatedly activated by the saturation indication signal; wherein the digital filter is arranged between the envelope detection circuit and the automatic gain control module.

[0087] When the envelope detection circuit detects an input signal from the LNA output that exceeds a preset power level, it outputs a preset level saturation indication signal to the digital filter. The envelope detection circuit sets a reporting threshold. The digital filter receives the preset level saturation indication signal, filters out interference glitches, and reports the processed digital signal to the automatic gain control module. The automatic gain control module receives power information reported by the main link ADC or via the digital filter. Upon receiving the processed digital signal, it transmits it to the VGA control terminal and the LNA bias terminal according to the preset gain control level.

[0088] like Figure 3As shown, the embodiment of this specification adopts an analog peak detection + digital filtering architecture. The envelope detection circuit is set after the LNA and before the mixer. The appropriate power detection threshold can be set according to the application scenario to report the high-power input signal to the auxiliary receiving link for fast power control. The fast envelope detection indication has a response time of hundreds of nanoseconds.

[0089] like Figure 4 As shown, set the appropriate envelope detection reporting threshold according to the application scenario. The envelope detection reporting threshold can be set in 1dB steps based on different design threshold values and accuracy. Envelope detection reporting has higher priority and faster speed.

[0090] When the envelope detector detects an input signal from the LNA output that exceeds a preset power level, it outputs a high-level saturation indication signal to the data filter. The digital filter, located between the envelope detector and the automatic gain control module, filters the saturation indication signal. It receives the high-level saturation indication signal and smoothes it, removing glitches and jitter. This prevents sudden interference and power detection jitter near the detection threshold, thereby enhancing the robustness of the automatic gain control.

[0091] The automatic gain control module automatically adjusts the receiver link gain by integrating envelope detection power information with the output power detection information from the ADC on the main link. This provides fast gain control and low cost. Compared to traditional automatic gain control, which requires multiple gain adjustments based solely on power statistics from the main link ADC or auxADC sampling data, the fast envelope detection and digital filter in this embodiment provide additional information, improving the system's automatic gain control response speed.

[0092] In some embodiments, the automatic gain control module further includes performing multi-segment power gain rapid response control according to multiple power threshold indications reported by envelope detection.

[0093] In combination with the above embodiments, the power threshold of the envelope detection circuit can be adaptively set to meet the needs of fast power detection thresholds in different application scenarios, such as setting three thresholds of high, medium and low. Each threshold can be set with upper and lower ranges to support multi-channel parallel operation; the envelope detection reporting threshold can be set in steps of up to 1dB according to different design threshold values and accuracy.

[0094] The automatic gain control module performs fast response control of multi-segment power gain according to multiple power threshold indications reported by envelope detection.

[0095] In some embodiments, the envelope detection circuit is further configured to set multiple thresholds and perform separate adjustments based on the priority corresponding to each threshold.

[0096] In combination with the above-mentioned embodiment, the fast envelope detection circuit is provided with multiple thresholds, and thus can perform priority sequence threshold control for multiple scenarios and complex signals, making the application more flexible and safe.

[0097] In some embodiments, the gain control gears pre-set in the automatic gain control module are associated with different signal power ranges, and also include: directly sending it to each connected module in the receiving link for control according to the pre-set gain control gear; or, when the envelope detection indication reporting signal is not received, power adjustment is performed according to the power information reported by the ADC.

[0098] like Figure 3 As shown, the gain control gears preset in the automatic gain control module are associated with different signal power ranges, so that they can be directly sent to each connected module in the receiving link according to the preset gain control gears for rapid control.

[0099] After receiving the envelope detection power reporting indication, the fast automatic gain control module will directly send it to each module of the receiving link for rapid control according to the pre-set gain control gear, without the need for small gear step adjustment, thereby improving the AGC response speed of the entire link.

[0100] The automatic gain control module determines whether a rapid gain adjustment of the RF circuit is required based on the power level information.

[0101] After a quick gain adjustment, the automatic gain control module integrates the power information statistically collected by the main ADC to perform a second fine-tuning of the RF circuit.

[0102] When the automatic gain control module does not receive the envelope detection indication report, it will perform fine power adjustment based on the power information reported by the ADC to meet higher precision system requirements.

[0103] In summary, the envelope detection circuit is provided in the embodiments of this specification, which realizes a fast power detection function in the analog domain by directly detecting the envelope of the RF signal. Compared with the traditional intermediate frequency detection circuit, it has the advantages of short delay and fast detection speed.

[0104] The envelope detector circuit is located after the low-noise amplifier and before the mixer. The envelope detector circuit has a configurable power threshold to meet the needs of different application scenarios for fast power detection thresholds.

[0105] The envelope detection circuit supports the configuration of multiple power thresholds to achieve multi-level parallel detection. Compared with traditional solutions 1 and 2, it has the advantage of fast detection speed and low implementation cost compared with solution 2.

[0106] A digital filter is also provided, which is set between the envelope detection circuit and the automatic gain control module to smooth the output of the envelope detection circuit and filter out burrs and jitter, prevent sudden interference and power detection jitter in scenarios where the power is near the detection threshold, and increase the robustness of the automatic gain control scheme.

[0107] When the envelope detection circuit sets different detection gear branches, no additional circuit design is required. Since the reporting digital interface is multi-channel parallel, an independent digital filter is set for each gear branch, that is, the number of digital filters needs to be increased accordingly, which has little impact on the circuit area and power consumption.

[0108] The automatic gain control module automatically adjusts the receiver link gain by integrating envelope detection power information with the main ADC output power detection information. This provides fast gain control and low cost. Compared to traditional automatic gain controllers that rely solely on power statistics from the main ADC or auxADC sample data to make multiple gain adjustments, fast envelope detection and digital filters provide additional information, improving the system's automatic gain control response speed.

[0109] The automatic gain controller (AGC) uses the power level information output by the envelope detector and digital filter to determine whether a rapid gain adjustment of the RF circuit is necessary. After this rapid gain adjustment, it then integrates the power information from the main ADC to perform a second, fine-tuned adjustment of the RF circuit.

[0110] In combination with the above embodiments, an embodiment of this specification also provides a receiver, which applies an automatic gain control system based on RF envelope detection as described in any of the above technical solutions or an automatic gain control method based on RF envelope detection as described in any of the above technical solutions to convert the received radio signal into a digital signal for subsequent processing and communication operations.

[0111] The same or similar parts between the various embodiments in this specification can be referred to in conjunction with each other. Each embodiment focuses on the differences from other embodiments. In particular, for the product embodiments described later, since they correspond to the methods, the description is relatively simple. For relevant parts, please refer to the partial description of the system embodiment.

[0112] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. An automatic gain control system based on radio frequency envelope detection, characterized in that: include: Main link circuit, envelope detection circuit, automatic gain control module; The main link circuit is provided with a low noise amplifier, a mixer, a low pass filter, a variable gain amplifier, and an analog-to-digital converter in sequence; An input terminal of the low noise amplifier is connected to the antenna, and an output terminal of the low noise amplifier is connected to an input terminal of the mixer; Connection between the bias terminal of the low noise amplifier and the automatic gain control module; The output end of the low noise amplifier is also connected to the envelope detection circuit, and the envelope detection circuit is connected to the automatic gain control module; The envelope detection circuit sets a reporting threshold for outputting a preset level saturation indication signal to the automatic gain control module when an input signal greater than a preset power is detected from the output end of the low noise amplifier; The control end of the variable gain amplifier is connected to the automatic gain control module; the output end of the analog-to-digital converter is connected to the automatic gain control module; The automatic gain control module is used to receive the power reporting information of the main link analog-to-digital converter or the power indication information reported by the envelope detection, and when receiving the preset level saturation indication signal, it is sent to the control end of the variable gain amplifier or the bias end of the low noise amplifier according to the pre-set gain control gear.

2. The automatic gain control system based on radio frequency envelope detection according to claim 1, characterized in that: It also includes a digital filter, which is arranged between the envelope detection circuit and the automatic gain control module; The digital filter is used to receive the preset level saturation indication signal and perform smoothing, burr and jitter filtering, and report the processed digital signal to the automatic gain control module to ensure that the automatic gain control module will not be frequently and repeatedly activated by the saturation indication signal.

3. The automatic gain control system based on radio frequency envelope detection according to claim 1, characterized in that: The envelope detection circuit is configured with multiple thresholds, each threshold being configured with corresponding upper and lower intervals, and supports multi-channel parallel operation; The automatic gain control module performs multi-segment power gain rapid response control according to multiple power threshold indications reported by envelope detection.

4. The automatic gain control system based on radio frequency envelope detection according to claim 1, characterized in that: The envelope detection circuit is provided with a plurality of thresholds, and is regulated separately according to the priority corresponding to each threshold.

5. The automatic gain control system based on radio frequency envelope detection according to claim 2, characterized in that: The envelope detection circuit is provided with a plurality of thresholds, and branches at different detection gears are respectively connected to independent digital filters.

6. The automatic gain control system based on radio frequency envelope detection according to claim 1, characterized in that: The gain control gears pre-set in the automatic gain control module are associated with different signal power ranges so that they can be directly sent to each connected module in the receiving link according to the pre-set gain control gears for rapid control. Alternatively, the automatic gain control module is also used to adjust the power according to the power information reported by the analog-to-digital converter when no envelope detection indication reporting signal is received.

7. An automatic gain control method based on radio frequency envelope detection, characterized in that: include: When the envelope detection circuit detects an input signal from the output end of the low noise amplifier that is greater than a preset power, it outputs a preset level saturation indication signal to the automatic gain control module; wherein the envelope detection circuit sets a reporting threshold; The automatic gain control module receives the power reporting information of the main link analog-to-digital converter or the power indication information reported by the envelope detection circuit. When it receives the preset level saturation indication signal, it sends it to the control end of the variable gain amplifier and the bias end of the low noise amplifier according to the pre-set gain control gear.

8. The automatic gain control method based on radio frequency envelope detection according to claim 7, characterized in that: Also includes: The digital filter receives the preset level saturation indication signal and performs smoothing, burr and jitter filtering, and reports the processed digital signal to the automatic gain control module to ensure that the automatic gain control module is not frequently and repeatedly activated by the saturation indication signal; The digital filter is arranged between the envelope detection circuit and the automatic gain control module.

9. The automatic gain control method based on radio frequency envelope detection according to claim 7, characterized in that: Also includes: The envelope detection circuit is provided with multiple thresholds, and is regulated separately according to the priority corresponding to each threshold; Alternatively, the automatic gain control module performs multi-segment power gain rapid response control according to multiple power threshold indications reported by envelope detection.

10. A receiver, characterized in that: Apply the automatic gain control system based on radio frequency envelope detection described in any one of claims 1 to 6 or the automatic gain control method based on radio frequency envelope detection described in any one of claims 7 to 9 to convert the received radio signal into a digital signal for subsequent processing and communication operations.

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