A system and method for rapid AGC

Abstract

This invention discloses a fast AGC system and method, including an AGC controller. The AGC controller has multiple input terminals and multiple gain control transmitters. Each input terminal is connected to an RX channel output terminal. An ADC module and a digital detector module are sequentially connected between the RX channel output terminal and the AGC controller input terminals. A gain control receiver is provided on the RX channel, and the gain control receiver is connected to the gain control transmitter in a one-to-one correspondence. The AGC has a fast response time, does not require a detector channel and corresponding ADC and digital circuits, has a simple circuit, utilizes the receiving channel of an existing multi-antenna system, and has low cost.

Description

Technical Field

[0001] This invention belongs to the field of radio waves and relates to a system and method for rapid AGC. Background Technology

[0002] Due to the diversity of radio wave propagation space, the input signal to a wireless receiver will have different signal amplitude characteristics at different locations and times. The analog link gain of the receiver needs to be adjusted in real time according to the magnitude of the input signal to ensure that the digital signal is within the optimal signal amplitude range. This is the significance of AGC (Automatic Gain Control).

[0003] Most existing AGC methods are implemented in these two ways:

[0004] 1) Successive Adjustment Method. This method involves adjusting the gain after each signal input. If the circuit detects that the signal amplitude is too large, it reduces the gain accordingly; conversely, if the amplitude is too small, it increases the gain. After each gain adjustment, the amplitude of the input signal is re-detected, and this process is repeated until the signal amplitude meets the desired requirements.

[0005] 2) Detector detection method. In this method, in addition to passing through analog and digital link channels, a portion of the input RF signal is coupled out and sent to a detector for detection. This converts the signal power into voltage, then reads the voltage value through an ADC circuit, calculates the signal power in the digital domain, and finally determines the link gain value directly based on the current signal power, so that the adjusted signal amplitude exactly meets the desired requirements.

[0006] However, the successive adjustment method has the problem of slow adjustment response time because it requires multiple adjustments. For increasingly scarce wireless time and frequency resources, the excessively long AGC adjustment time will seriously affect the effective utilization of the spectrum. Although the detector method can quickly converge the adjustment process, it requires an additional analog detection channel, as well as corresponding ADC and digital circuits, which results in high circuit complexity and increased manufacturing and maintenance costs. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a fast AGC system and method. The AGC has a fast response time, does not require a detection channel or corresponding ADC and digital circuits, has a simple circuit, utilizes the receiving channel of an existing multi-antenna system, and has low cost.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] A system for rapid AGC, including an AGC controller;

[0010] The AGC controller has multiple input terminals and multiple gain control transmitter terminals. Each input terminal is connected to an RX channel output terminal. An ADC module and a digital detector module are connected sequentially between the RX channel output terminal and the AGC controller input terminal. A gain control receiver terminal is set on the RX channel, and the gain control receiver terminal is connected to the gain control transmitter terminal in a one-to-one correspondence.

[0011] Preferably, each RX channel is equipped with an independent gain adjustment circuit.

[0012] Preferably, each RX channel has an antenna connected to its input terminal.

[0013] Preferably, the RX channel includes a front end and multiple back ends. Each ADC module and gain control transmitter is connected to one back end of the RX channel. The input ends of multiple RX channel back ends are connected to the output end of one RX channel front end. The input end of the RX channel front end is connected to an antenna.

[0014] A fast AGC method for the system, characterized by comprising the following steps:

[0015] S1: The AGC controller sets the gain of each RX channel to different gain values, so that the gain of each channel is at different levels;

[0016] S2: After the received signal passes through each RX channel with different gains, it is sampled by the ADC module and sent to the digital detection module. The digital detection module calculates the power value of each RX channel.

[0017] S3: The AGC controller processes the power values ​​of each RX channel to obtain the correct AGC gain configuration result and controls the corresponding RX channel gain.

[0018] S4: AGC ends, and the system enters normal signal reception mode.

[0019] Preferably, the gain setting rule for the RX channel of S1 is as follows, assuming the maximum gain of the RX channel is G. max Given an input RF signal with a dynamic range of R (dB) and M RX channels, find the initial gain G of each RX channel m (m = 1, 2, ..., M). m Set to:

[0020]

[0021] Preferably, the process by which the S3 AGC controller obtains the correct AGC gain configuration result is as follows: assuming the power of the digital signal in the m-th receiving channel is P m (dBFS), the upper threshold of digital demodulation power is P. H (dBFS), the lower threshold of digital demodulation power is P.L (dBFS), let G be the correct AGC gain, and compare P in turn. m and P H and P L There are two cases, if P H >P m >P L Then G = G m +P H -P m If there is no P m Satisfy P H >P m >P L Without loss of generality, assume that the digital signal power P of the k-th and k+1-th channels is... k and P k+1 Satisfy: P k >P H >P L >P k+1 Then G = (G k+1 +G k ) / 2.

[0022] Preferably, before S1, the AGC controller is instructed to enter the receiving mode by the transceiver switch T / R signal.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention, by setting up a multi-channel RX architecture, first sets different gains, and then obtains the correct AGC gain configuration result based on the power value. Compared with the existing successive adjustment method, it does not require iteration and has a faster AGC response time. Compared with the existing detector detection method, it does not require a detection channel and corresponding ADC and digital circuits, making the circuit simple. It can utilize the RX channels of existing multi-antenna systems and has a low cost. Attached Figure Description

[0025] Figure 1 This is a system block diagram of the rapid AGC of the present invention;

[0026] Figure 2 This is a timing diagram showing the gain variation of each RX channel in this invention;

[0027] Figure 3 This is a block diagram of the single-antenna system of the present invention. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that the terms “front,” “back,” “left,” “right,” “up,” and “down” used in the following description refer to the directions shown in the attached diagram, while the terms “inside” and “outside” refer to the directions toward or away from the geometric center of a specific component, respectively.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0031] like Figure 1 As shown, the fast AGC device of the present invention includes multiple RX channels and an AGC controller.

[0032] The AGC controller has multiple input terminals and multiple gain control transmitter terminals. Each input terminal is connected to an RX channel output terminal. An ADC module and a digital detector module are sequentially connected between the RX channel output terminal and the AGC controller input terminal. Each RX channel has a gain control receiver terminal, which is connected one-to-one with the gain control transmitter terminal. Each RX channel input terminal is connected to an antenna.

[0033] Each RX channel is equipped with an independent adjustable gain adjustment (i.e., amplification and / or attenuation) circuit.

[0034] The ADC module samples analog signals into digital signals.

[0035] The function of the digital detector module is to calculate the power or amplitude of the input digital signal. The digital detector module and the AGC controller are the digital processing part of the system.

[0036] The AGC controller is responsible for controlling the entire AGC process, calculating gain, and providing feedback control output. The AGC controller is connected to a transceiver switch (T / R).

[0037] The workflow of the entire system is as follows:

[0038] S1: After the AGC controller enters the receiving mode indicated by the transmit / receive switch T / R signal, the AGC controller first sets the gain of each RX channel to different gain values, that is, adjusts the gain / attenuation of each RX channel so that the gain of each RX channel is at different levels.

[0039] S2: When the antenna receives the incoming signal, the signal passes through each RX channel with different gains and is sampled by the ADC. The digital signal is then sent to the digital detection module in the digital processing section, which calculates the power value of each RX channel.

[0040] S3: The AGC controller processes the power values ​​of each RX channel to obtain the correct AGC gain configuration result (i.e., the gain of the RF link) and controls the corresponding RX channel gain.

[0041] S4: AGC ends, and the system enters normal signal reception mode.

[0042] The timing diagram of gain changes in each RX channel during the AGC adjustment process is as follows: Figure 2 As shown.

[0043] The gain setting rules for the RX channel of S1 are as follows, assuming the maximum gain of the RX channel is G. max Given an input RF signal with a dynamic range of R (dB) and M RX channels, find the initial gain G of each RX channel m (m = 1, 2, ..., M). m Set to:

[0044]

[0045] The process by which the S3 AGC controller obtains the correct AGC gain configuration result is as follows: Assume the power of the digital signal in the m-th receiving channel is P. m (dBFS), the upper threshold of digital demodulation power is P. H (dBFS), the lower threshold of digital demodulation power is P. L (dBFS), let G be the correct AGC gain, and compare P in turn. m and P H and P L There are two cases, if P H >P m >P L Then G = G m +P H -P m If there is no P m Satisfy P H >P m >P L Without loss of generality, assume that the digital signal power P of the k-th and k+1-th channels is... k and Pk+1 Satisfy: P k >P H >P L >P k+1 Then G = (G k+1 +G k ) / 2.

[0046] like Figure 3 As shown, another implementation is disclosed, in which the RX channel includes a front end and multiple back ends. Each ADC module and gain control transmitter are connected to one of the back ends of the RX channel. The inputs of multiple RX channel back ends are connected to the output of one RX channel front end. The input of the RX channel front end is connected to an antenna.

[0047] That is, when a single antenna enters multiple RX channels, in addition to the shared front-end amplifier circuit, the gain of each RX channel is set differently at the back end.

[0048] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0049] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A method of fast AGC, characterized by, A system for rapid AGC, the system including an AGC controller; The AGC controller is equipped with multiple input terminals and multiple gain control transmitter terminals. Each input terminal is connected to an RX channel output terminal. An ADC module and a digital detector module are connected sequentially between the RX channel output terminal and the AGC controller input terminal. A gain control receiver terminal is set on the RX channel, and the gain control receiver terminal is connected to the gain control transmitter terminal in a one-to-one correspondence. The method includes the following steps: S1: The AGC controller sets the gain of each RX channel to different gain values, so that the gain of each channel is at different levels; S2: After the received signal passes through each RX channel with different gains, it is sampled by the ADC module and sent to the digital detection module. The digital detection module calculates the power value of each RX channel. S3: The AGC controller processes the power values ​​of each RX channel to obtain the correct AGC gain configuration result and controls the corresponding RX channel gain. S4: AGC ends, and the system enters normal signal reception mode.

2. The fast AGC method of claim 1, wherein, Each RX channel is equipped with an independent gain adjustment circuit.

3. The fast AGC method of claim 1, wherein, Each RX channel has an antenna connected to its input.

4. The fast AGC method of claim 1, wherein, The RX channel consists of a front end and multiple back ends. Each ADC module and gain control transmitter is connected to one of the back ends of the RX channel. The inputs of multiple RX channel back ends are connected to the output of one RX channel front end. The input of the RX channel front end is connected to an antenna.

5. The rapid AGC method according to claim 1, characterized in that, The gain setting rules for the RX channel of S1 are as follows, assuming the maximum gain of the RX channel is... The dynamic range of the input RF signal is R, in dB. There are M RX channels. What is the initial gain of RX channel m? Set to: ； Where m = 1, 2, ..., M.

6. The rapid AGC method according to claim 1, characterized in that, The process by which the S3 AGC controller obtains the correct AGC gain configuration result is as follows: Assume the power of the digital signal in the m-th receiving channel is... The unit is The upper threshold of digital demodulation power is The unit is The lower threshold of digital demodulation power is Units are Let the correct AGC gain be... Compare in turn and and There are two situations, if ,but If there is none Without loss of generality, assume the digital signal power of the k-th and k+1-th channels is... and satisfy: ,but .

7. The rapid AGC method according to claim 1, characterized in that, Before S1, the AGC controller enters the receive mode as indicated by the transmit / receive switch T / R signal.

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