Small signal detection circuit, device and method

Abstract

The invention discloses a small signal detection circuit, device and method, and belongs to the technical field of power electronics. The circuit comprises an amplitude adjusting module, a signal conversion module and a control module which are connected in sequence, and further comprises a receiving module, the input end of the amplitude adjusting module is connected with the first output end of the receiving module, and the output end of the control module is connected with the control end of the receiving module. The signal conversion module comprises a detector and a comparison sub-module which are connected in sequence; under the condition that the receiving module receives a first radio frequency signal, the receiving module samples the first radio frequency signal to obtain a coupling signal, the coupling signal is output through a first output end, the amplitude adjusting module attenuates or amplifies the coupling signal to generate an adjusting signal, and the adjusting signal is output through a second output end. The detector performs power detection on the adjustment signal to generate a detection signal, the comparison sub-module compares the detection signal to generate a comparison signal, and the control module determines the power range of the first radio frequency signal according to the comparison signal, generates a control signal and outputs the control signal to the control end of the receiving module. And the receiving module is used for adjusting the gain of the first radio frequency signal according to the control signal, generating a second radio frequency signal and outputting the second radio frequency signal through a second output end. The circuit can realize linear response, has high resistance to noise and interference, and can perform small signal detection.

Description

Technical Field

[0001] The present application belongs to the field of power electronics technology, and in particular, relates to a small signal detection circuit, device and method. Background Art

[0002] The detection circuit design is generally used to detect whether the whole system is working normally, or to achieve the effect of gain control of the whole system through the detection circuit.

[0003] The RF signal of the main circuit of the whole system generates a branch signal through the coupler and enters the detection circuit. The detection circuit converts the RF signal into an electrical signal and feeds it back to the control system. The control system controls the gain of the main circuit of the system according to the input electrical signal.

[0004] Most traditional detection circuits use diode detection. Due to the characteristics of the diode itself, this circuit has nonlinear problems, unstable output levels, poor resistance to noise and interference, and cannot perform small signal detection. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a small signal detection circuit, device and method, which can achieve linear response, have high resistance to noise and interference, and can perform small signal detection.

[0006] In a first aspect, the present application provides a small signal detection circuit, the circuit comprising: an amplitude adjustment module, a signal conversion module and a control module connected in sequence, and also comprising a receiving module, the input end of the amplitude adjustment module is connected to the first output end of the receiving module, the output end of the control module is connected to the control end of the receiving module, and the signal conversion module comprises a detector and a comparison submodule connected in sequence;

[0007] In the case where the receiving module receives a first radio frequency signal, the receiving module samples the first radio frequency signal and outputs a coupled signal through a first output terminal. The amplitude adjustment module attenuates or amplifies the coupled signal to generate an adjustment signal. The detector performs power detection on the adjustment signal to generate a detection signal. The comparison submodule compares the detection signals to generate a comparison signal. The control module determines a power range of the first radio frequency signal according to the comparison signal and generates a control signal to output to the control terminal of the receiving module. The receiving module is used to adjust the gain of the first radio frequency signal according to the control signal and generate a second radio frequency signal to output through the second output terminal.

[0008] According to one embodiment of the present application, the comparison submodule includes a first dual-way comparator and a second dual-way comparator;

[0009] The first dual-path comparator includes a first comparison branch and a second comparison branch, the first comparison branch is provided with a first threshold, the second comparison branch is provided with a second threshold, the second dual-path comparator includes a third comparison branch and a fourth comparison branch, the third comparison branch is provided with a third threshold, and the fourth comparison branch is provided with a fourth threshold;

[0010] The comparison signal includes a first comparison signal, a second comparison signal, a third comparison signal and a fourth comparison signal;

[0011] When the comparison submodule receives the detection signal, the first comparison branch compares the power value corresponding to the detection signal with the first threshold value to generate the first comparison signal, the second comparison branch compares the power value corresponding to the detection signal with the second threshold value to generate the second comparison signal, the third comparison branch compares the power value corresponding to the detection signal with the third threshold value to generate the third comparison signal, and the fourth comparison branch compares the power value corresponding to the detection signal with the fourth threshold value to generate the fourth comparison signal.

[0012] According to one embodiment of the present application, the first threshold is -65dBm, the second threshold is -55dBm, the third threshold is -45dBm, and the fourth threshold is -35dBm.

[0013] According to one embodiment of the present application, the model of the detector is MW1861, and the model of the first dual comparator and the second dual comparator is SGM8745.

[0014] According to an embodiment of the present application, the signal conversion module further includes an equalizer, and the detector is connected to the amplitude adjustment module via the equalizer.

[0015] According to one embodiment of the present application, the control module is further used to:

[0016] The power range of the first radio frequency signal is determined according to the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal, and the control signal corresponding to the power range is output.

[0017] According to one embodiment of the present application, the amplitude adjustment module includes a first attenuator, a first operational amplifier, a second attenuator and a second operational amplifier connected in sequence, the first attenuator and the second attenuator attenuate the coupled signal, and the first operational amplifier and the second operational amplifier amplify the coupled signal.

[0018] According to an embodiment of the present application, the models of the first attenuator and the second attenuator are IFA-03, and the models of the first operational amplifier and the second operational amplifier are ILA-0118C.

[0019] In a second aspect, the present application provides a small signal detection device, which includes the small signal detection circuit as described in the first aspect.

[0020] In a third aspect, the present application provides a small signal detection method, which is applied to the small signal detection circuit as described in the first aspect, wherein the signal detection circuit includes an amplitude adjustment module, a signal conversion module and a control module connected in sequence, and also includes a receiving module, wherein the input end of the amplitude adjustment module is connected to the first output end of the receiving module, the output end of the control module is connected to the control end of the receiving module, and the signal conversion module includes a detector and a comparison submodule connected in sequence, and the method includes:

[0021] When the receiving module receives a first radio frequency signal, the first radio frequency signal is sampled by the receiving module to obtain a coupled signal, which is output through the first output terminal;

[0022] Attenuating or amplifying the coupling signal by the amplitude adjustment module to generate an adjustment signal;

[0023] Performing power detection on the adjustment signal by the detector to generate a detection signal;

[0024] The detection signal is compared by the comparison submodule to generate a comparison signal;

[0025] The control module determines the power range of the first RF signal according to the comparison signal, and generates a control signal to output to the control end of the receiving module. The receiving module is used to adjust the gain of the first RF signal according to the control signal, and generate a second RF signal to output through the second output end.

[0026] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application.

[0027] The small signal detection circuit, device and method provided by the present application have the following beneficial effects compared with the prior art:

[0028] (1) The amplitude of the first RF signal is changed by adjusting or attenuating the gain of the receiving module, and a detector is selected instead of a detection diode for power detection, which solves the problem of nonlinear error of the diode and realizes linear response. The power comparison is performed by the comparison submodule, and the corresponding level is output to the control module. The power detection and power comparison can more stably and reliably adjust the gain of the receiving module to the first RF signal, avoid the gain adjustment instability caused by amplitude fluctuation, effectively reduce the influence of noise, and more comprehensively control the power of the second RF signal. The noise and interference resistance is high, and small signal detection can be performed.

[0029] (2) The small signal detection circuit can be applied to the RF receiving system to sample and power-detect the received first RF signal. For different input thresholds, the corresponding level is output to the control module through the comparator. The control module outputs different instructions according to the received level to change the gain of the receiving module for the first RF signal. The RF signal power can be monitored and adjusted in real time. The obtained second RF signal can avoid the signal being too weak to cause poor communication quality, or too strong to cause system overload or interference. According to different environmental changes, the system can automatically adjust the power of the second RF signal to ensure that the system can operate stably under different conditions. Through the cooperation of different modules, the circuit can realize dynamic adjustment of the signal power to optimize the signal quality and system performance.

[0030] (3) The power of the first RF signal is judged by power, and the attenuation value of the operational amplifier in the receiving module is set to achieve control of the gain of the first RF signal; compared with the poor linear response and anti-interference performance of voltage detection in the existing technology, which leads to low adjustment accuracy, the small signal detection circuit of the present application can provide better linear response through power detection, has stronger resistance to noise and interference, can process a wider power range of the first RF signal, can better reflect the signal quality, and is suitable for applications requiring high precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0032] Figure 1 This is one of the structural schematic diagrams of the small signal detection circuit provided in the embodiment of the present application;

[0033] Figure 2 This is the second structural diagram of the small signal detection circuit provided in the embodiment of the present application;

[0034] Figure 3 is a structural diagram of an amplitude adjustment module provided in an embodiment of the present application;

[0035] Figure 4is a structural diagram of a signal conversion module provided in an embodiment of the present application;

[0036] Figure 5 It is a flowchart of a small signal detection method provided in an embodiment of the present application;

[0037] Reference numerals:

[0038] Amplitude adjustment module 110 , signal conversion module 120 , control module 130 , receiving module 140 . DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0040] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0041] The small signal detection circuit, small signal detection device and small signal detection method provided in the embodiments of the present application are described in detail below with reference to the accompanying drawings through specific embodiments and their application scenarios.

[0042] Among them, the small signal detection method can be applied to a small signal detection circuit for execution.

[0043] like Figure 1 and Figure 2 As shown, the small signal detection circuit includes: an amplitude adjustment module 110, a signal conversion module 120 and a control module 130 connected in sequence, and also includes a receiving module 140, the input end of the amplitude adjustment module 110 is connected to the first output end of the receiving module 140, the output end of the control module is connected to the control end of the receiving module, and the signal conversion module 120 includes a detector and a comparison submodule connected in sequence;

[0044] In the case where the receiving module receives a first radio frequency signal, the receiving module samples the first radio frequency signal to obtain a coupled signal and outputs it through the first output terminal; the amplitude adjustment module attenuates or amplifies the coupled signal to generate an adjustment signal; the detector performs power detection on the adjustment signal to generate a detection signal; the comparison submodule compares the detection signals to generate a comparison signal; the control module determines the power range of the first radio frequency signal according to the comparison signal, and generates a control signal to output to the control terminal of the receiving module; the receiving module is used to adjust the gain of the first radio frequency signal according to the control signal, and generate a second radio frequency signal to output it through the second output terminal.

[0045] When the small signal detection circuit receives a first radio frequency signal from a radio frequency source such as an antenna or a transmitter, the signal is processed, and the first radio frequency signal has a certain power and frequency.

[0046] The detector can be an envelope detector or a synchronous detector.

[0047] The receiving module includes a sampling circuit and an operational amplifier circuit. The control signal received by the control end of the receiving module is used to adjust the gain of the operational amplifier circuit to the first radio frequency signal.

[0048] In actual execution, when the receiving module receives the first RF signal, the first RF signal is sampled by the sampling circuit to obtain a coupled signal, and the amplitude of the coupled signal is lower than the amplitude of the first RF signal. After receiving the coupled signal, the amplitude adjustment module 110 changes the amplitude of the coupled signal through gain adjustment or attenuation to adjust the amplitude of the input coupled signal to a range that can be processed by subsequent circuit modules, obtains the adjusted signal and outputs it to the signal conversion module 120.

[0049] For example, if the amplitude of the coupled signal is too low, the amplitude adjustment module 110 will increase the coupled signal through gain; if the amplitude of the coupled signal is too high, the amplitude adjustment module 110 will choose to attenuate the coupled signal to avoid overload.

[0050] In the signal conversion module 120, the detector performs power detection on the adjustment signal, analyzes and extracts information from the amplitude, frequency and other characteristics of the adjustment signal to obtain a detection signal. A reference power threshold is set in the comparison submodule as a threshold to convert the detection signal into high and low levels that can be used for subsequent processing to obtain a comparison signal.

[0051] The detector performs signal rectification and filtering on the adjustment signal to obtain the effective amplitude of the adjustment signal, and calculates the power of the first RF signal to obtain a detection signal that can characterize the power of the first RF signal. The comparison signal can reflect the actual power value or other characteristics of the first RF signal.

[0052] The control module 130 determines the amplitude, power or signal quality-related parameters represented by the high and low levels according to the high and low levels of the comparison signal, judges the power range of the first RF signal, generates a corresponding control signal, and sends the control signal to the control end of the receiving module 140, which will be used to instruct the operational amplifier circuit in the receiving module 140 to adjust the gain or attenuation of the first RF signal to generate a second RF signal.

[0053] For example, if the power of the first RF signal is too high or too low, the corresponding first RF signal exceeds a predetermined range, and the control module 130 generates a control signal, which may be a digital signal or an analog signal, instructing the operational amplifier circuit in the receiving module 140 to adjust the gain or attenuation of the first RF signal.

[0054] For example, the small signal detection circuit is used for signal conditioning in wireless communications, especially in a base station or relay station environment, where the system needs to maintain stable signal quality under different environmental conditions.

[0055] For example, the signal power of a first RF signal received from a remote wireless terminal is -60dBm, which is lower than the lower limit of the required target power range, such as -50dBm. To ensure that the signal is strong enough, the operational amplifier circuit in the receiving module 140 amplifies the input first RF signal, sets the gain to 10dB, and outputs a signal power of -50dBm to generate a second RF signal.

[0056] The signal conversion module 120 converts the adjustment signal into a detection signal, and evaluates the power of the first RF signal by processing the detection signal to obtain a comparison signal. If the power of the first RF signal reaches the expected power of -50 dB, the gain will not be further adjusted.

[0057] The control module 130 determines whether the first RF signal has reached the target power by comparing the signals. If the power of the first RF signal is too high, for example, exceeding -50dBm, the control module 130 will send a control signal to instruct the operational amplifier circuit in the receiving circuit 140 to attenuate; if the signal power of the first RF signal is lower than expected, the control module 130 will send a control signal to instruct the operational amplifier circuit gain in the receiving circuit 140 until the power of the second RF signal stabilizes within the target power range.

[0058] According to the small signal detection circuit provided in the embodiment of the present application, the amplitude of the first radio frequency signal is changed by adjusting the gain or attenuation of the receiving module, and a detector is selected instead of a detection diode for power detection, which solves the problem of nonlinear error of the diode and achieves linear response. The power comparison is performed through the comparison submodule, and the corresponding level is output to the control module. The power detection and power comparison can more stably and reliably adjust the gain of the receiving module to the first radio frequency signal, avoid unstable gain adjustment caused by amplitude fluctuations, effectively reduce the influence of noise, and more comprehensively control the power of the second radio frequency signal. The circuit has high resistance to noise and interference and can perform small signal detection.

[0059] In some embodiments, Figure 3 As shown, the amplitude adjustment module 110 includes a first attenuator, a first operational amplifier, a second attenuator and a second operational amplifier connected in sequence, the first attenuator and the second attenuator attenuate the coupled signal, and the first operational amplifier and the second operational amplifier amplify the coupled signal.

[0060] Among them, the first attenuator FA1 and the second attenuator FA2 are both digitally controlled attenuators. The present application determines the power of the first RF signal by power, sets the attenuation value of the operational amplifier in the receiving module, and realizes the control of the gain of the first RF signal. Compared with the voltage detection in the existing technology, which has poor linear response and anti-interference performance, resulting in low adjustment accuracy, the small signal detection circuit of the present application can provide better linear response through power detection, has stronger resistance to noise and interference, can process a wider power range of the first RF signal, and can better reflect the signal quality, and is suitable for applications requiring high precision.

[0061] In the amplitude adjustment module 110, the first attenuator FA1 performs a first attenuation on the coupled signal to reduce the amplitude of the coupled signal and lower the coupled signal to a level suitable for subsequent processing to avoid nonlinear distortion or overload of the operational amplifier caused by an excessively strong coupled signal.

[0062] The first operational amplifier AMP1 performs a first amplification on the attenuated signal to increase the amplitude of the signal, and increases the amplitude of the signal to a required level according to the amplitude and gain requirements of the input signal.

[0063] The second attenuator FA2 performs a second attenuation on the amplified signal to adjust the amplified signal to a certain target range to avoid an overly strong signal that may cause overload or improper processing of subsequent circuits.

[0064] The second operational amplifier AMP2 amplifies the signal after the second attenuation for the second time, and increases the amplitude of the signal according to the set gain, so that the obtained regulated signal can be adjusted to a suitable level for subsequent processing or output.

[0065] In this embodiment, by sequentially connecting the first attenuator, the first operational amplifier, the second attenuator and the second operational amplifier, the problem that small signal detection cannot be performed in the traditional detection circuit can be improved. The double amplification of the signal by the first operational amplifier and the second operational amplifier can avoid the distortion introduced by the higher gain of a single operational amplifier. The attenuator can attenuate a part of the high-frequency noise component, the operational amplifier can amplify the useful part of the signal, and the amplitude range of the adjustment signal can be controlled to achieve precise adjustment of the signal amplitude.

[0066] In some embodiments, the first attenuator and the second attenuator are of model IFA-03, and the first operational amplifier and the second operational amplifier are of model ILA-0118C.

[0067] In this embodiment, the amplitude adjustment module 110 is constructed by using the first attenuator and the second attenuator of IFA-03 and the first operational amplifier AMP1 and the second operational amplifier AMP2 of ILA-0118C, which can cover the first RF signal with a wide frequency band of 2-18 and has a wider application range.

[0068] In some embodiments, the signal conversion module further includes an equalizer, and the detector is connected to the amplitude adjustment module via the equalizer.

[0069] In this embodiment, an equalizer is further provided in the signal conversion module 120, and the second operational amplifier is connected to the detector DET1 via the equalizer. The equalizer is used to improve the flatness of the signal, thereby improving the detection accuracy and outputting a more accurate signal to the detector DET1.

[0070] In some embodiments, Figure 4 As shown, the comparison submodule includes a first dual-way comparator and a second dual-way comparator;

[0071] The first dual-path comparator includes a first comparison branch and a second comparison branch, the first comparison branch is provided with a first threshold, the second comparison branch is provided with a second threshold, the second dual-path comparator includes a third comparison branch and a fourth comparison branch, the third comparison branch is provided with a third threshold, and the fourth comparison branch is provided with a fourth threshold;

[0072] The comparison signal includes a first comparison signal, a second comparison signal, a third comparison signal and a fourth comparison signal;

[0073] When the comparison submodule receives the detection signal, the first comparison branch compares the power value corresponding to the detection signal with the first threshold value to generate the first comparison signal, the second comparison branch compares the power value corresponding to the detection signal with the second threshold value to generate the second comparison signal, the third comparison branch compares the power value corresponding to the detection signal with the third threshold value to generate the third comparison signal, and the fourth comparison branch compares the power value corresponding to the detection signal with the fourth threshold value to generate the fourth comparison signal.

[0074] In some embodiments, the first threshold is -65dBm, the second threshold is -55dBm, the third threshold is -45dBm, and the fourth threshold is -35dBm.

[0075] In the signal conversion module 120, each branch of the first dual comparator CMPR1 and the second dual comparator CMPR2 is set with a different threshold, the threshold of the first comparison branch corresponds to the first threshold value of -65dBm, the threshold of the second comparison branch corresponds to the second threshold value of -55dBm, the threshold of the third comparison branch corresponds to the third threshold value of -45dBm, and the threshold of the fourth comparison branch corresponds to the fourth threshold value of -35dBm.

[0076] When the input power of the first RF signal corresponding to the detection signal is ≤-65dBm, the first comparison branch outputs the first comparison signal JB4 as a low level;

[0077] When the input power is greater than -65dBm, the first comparison branch outputs the first comparison signal JB4 as a high level;

[0078] When the input power is ≤-55dBm, the second comparison signal JB3 output by the second comparison branch is all at a low level;

[0079] When the input power is greater than -55dBm, the second comparison signal JB3 output by the second comparison branch is at a high level;

[0080] When the input power is ≤-45dBm, the third comparison signal JB2 output by the third comparison branch is all at a low level;

[0081] When the input power is greater than -45dBm, the third comparison signal JB2 output by the third comparison branch is at a high level;

[0082] When the input power is ≤-35dBm, the fourth comparison signal JB1 output by the fourth comparison branch is all at a low level;

[0083] When the input power is greater than -35 dBm, the fourth comparison signal JB1 output by the fourth comparison branch is at a high level.

[0084] In this embodiment, the two comparators of the dual comparator can work simultaneously, so that the circuit can not only detect whether the power of the first RF signal exceeds the upper threshold, for example, indicating that the first RF signal strength is too high or too low, but also detect whether the first RF signal is lower than the lower threshold, thereby realizing signal power monitoring and judgment.

[0085] In some embodiments, the detector is of model MW1861, and the first dual comparator and the second dual comparator are of model SGM8745.

[0086] In this embodiment, the signal conversion module 120 is constructed by using the detector MW1861 and the dual comparator SGM8745, which can cover the first radio frequency signal with a wide frequency band of 2-18 and has a wider application range.

[0087] In some embodiments, the control module 130 is further configured to:

[0088] The power range of the first radio frequency signal is determined according to the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal, and the control signal corresponding to the power range is output.

[0089] A control chip is provided in the control module. The control chip stores the attenuation values ​​of the first attenuator and the second attenuator, and the gains of the first operational amplifier and the second operational amplifier. The control chip determines the frequency range to which the first radio frequency signal belongs based on a combination of the first comparison signal JB4, the second comparison signal JB3, the third comparison signal JB2 and the fourth comparison signal JB1.

[0090] When JB1, JB2, JB3 and JB4 are all displayed as low levels, it means that the first RF signal is ≤-65dBm, and the control module returns a control signal to control the attenuation value of the operational amplifier circuit in the receiving module 140 to be 0dB;

[0091] When JB4 is at a high level and JB1, JB2 and JB3 are at a low level, it means that -65dBm<first RF signal≤-55dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 10dB;

[0092] When JB4 and JB3 are at high levels and JB1 and JB2 are at low levels, it means that -55dBm<first RF signal≤-45dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 20dB;

[0093] When JB4, JB3 and JB2 are at high level and JB1 is at low level, it means -45dBm<first RF signal≤-35dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 30dB;

[0094] When JB1, JB2, JB3 and JB4 are all at high levels, it means that the first RF signal is greater than -35dBm, and the attenuation value of the operational amplifier circuit in the control receiving module 140 is 40dB.

[0095] When the detection circuits JB1, JB2, JB3 and JB4 are displayed at a high level, the test data of the detection power of the first radio frequency signal is shown in Table 1.

[0096] Table 1 Detection power test data

[0097]

[0098]

[0099] This application provides a specific embodiment.

[0100] In the small signal detection circuit provided in the present application, the selected chips use a frequency band covering 2-18 GHz. The input power of the first radio frequency signal is -65 to -35 dBm.

[0101] The circuit is composed of an attenuator, an operational amplifier, an equalizer, a detector, a comparator, and a current detection chip.

[0102] Among them, the small signal detection circuit works on a +12V DC power supply, and the current detection chip selected is SGM8198. The current detection chip detects the current of the input +12V DC power supply, and generates and reports the health signal of the small signal detection circuit based on the detected current.

[0103] The coupled signal is amplified by an operational amplifier, which can improve the problem that small signals cannot be detected in traditional detection circuits. A detector is selected instead of a detection diode in detection to improve the problem of nonlinear errors in the diode. An equalizer is configured in the detection circuit to improve the detection accuracy of the detection circuit.

[0104] The frequency band of the first radio frequency signal applicable to the small signal detection circuit provided in the present application is 2-18 GHz, the power range of the detected first radio frequency signal is -65 to 25 dBm, and the detection error is ≤±2 dB.

[0105] First, the signal is amplified by the first attenuator, the first operational amplifier, the second attenuator and the second operational amplifier. The equalizer is used to improve the flatness of the signal, thereby improving the detection accuracy. The amplified adjustment signal is converted into an electrical signal through the detector. The electrical signal enters the comparator. By setting different thresholds for the comparator, the incoming electrical signal can be converted into a high and low level of 3.3V / 0V, which is output as a comparison signal to the control module 130. The control module 130 generates corresponding control instructions according to the input comparison signal to control the gain of the operational amplifier circuit in the receiving module 140.

[0106] The small signal detection circuit provided in the present application shares two dual-channel comparators. The electrical signal output by the detector is divided into four channels and enters the two comparators. The comparators convert the four channels of electrical signals into four channels of high and low levels JB1, JB2, JB3 and JB4 and output them to the control module. According to the display of the four channels of high and low levels, the input size of the first RF signal is judged, and then the gain of the operational amplifier circuit in the receiving module 140 is controlled.

[0107] When JB1, JB2, JB3 and JB4 are all displayed as low levels, it means that the first RF signal is ≤-65dBm, and the control module returns a control signal to control the attenuation value of the operational amplifier circuit in the receiving module 140 to be 0dB;

[0108] When JB4 is at a high level and JB1, JB2 and JB3 are at a low level, it means that -65dBm<first RF signal≤-55dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 10dB;

[0109] When JB4 and JB3 are at high levels and JB1 and JB2 are at low levels, it means that -55dBm<first RF signal≤-45dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 20dB;

[0110] When JB4, JB3 and JB2 are at high level and JB1 is at low level, it means -45dBm<first RF signal≤-35dBm, and the attenuation value of the operational amplifier circuit in the receiving module 140 is controlled to be 30dB;

[0111] When JB1, JB2, JB3 and JB4 are all at high levels, it means that the first RF signal is greater than -35dBm, and the attenuation value of the operational amplifier circuit in the control receiving module 140 is 40dB.

[0112] In this embodiment, the small signal detection circuit can be applied to the radio frequency receiving system, the received first radio frequency signal is sampled and power detected, and the corresponding level is output to the control module through the comparator for different input thresholds. The control module outputs different instructions according to the received level to change the gain of the receiving module for the first radio frequency signal, and the power of the second radio frequency signal can be monitored and adjusted in real time. The obtained second radio frequency signal can avoid the signal being too weak to cause poor communication quality, or too strong to cause system overload or interference. According to different environmental changes, the system can automatically adjust the power of the first radio frequency signal to ensure that the system can operate stably under different conditions. Through the cooperation of different modules, the circuit can realize dynamic adjustment of the power of the second radio frequency signal to optimize signal quality and system performance.

[0113] The present application provides a small signal detection device, which has a built-in small signal detection circuit as described in any of the above embodiments and can achieve the same technical effects, which will not be described in detail here.

[0114] The present application provides a small signal detection method, which is applied to the small signal detection circuit as described in any of the above embodiments, wherein the signal detection circuit includes an amplitude adjustment module, a signal conversion module and a control module connected in sequence, and also includes a receiving module 140, wherein the input end of the amplitude adjustment module 110 is connected to the first output end of the receiving module 140, the output end of the control module 130 is connected to the control end of the receiving module 140, and the signal conversion module includes a detector and a comparison submodule connected in sequence.

[0115] like Figure 5 As shown, the method includes:

[0116] Step 510: When the receiving module receives a first radio frequency signal, the receiving module samples the first radio frequency signal to obtain a coupled signal, which is output through the first output terminal;

[0117] Step 520: attenuate or amplify the coupling signal through the amplitude adjustment module to generate an adjustment signal;

[0118] Step 530: Perform power detection on the adjustment signal through the detector to generate a detection signal;

[0119] Step 540: Compare the detection signal through the comparison submodule to generate a comparison signal;

[0120] Step 550: determine the power range of the first RF signal according to the comparison signal through the control module, and generate a control signal to output to the control end of the receiving module, the receiving module is used to adjust the gain of the first RF signal according to the control signal, and generate a second RF signal to output through the second output end.

[0121] According to the small signal detection method provided by the embodiment of the present application, the amplitude of the first RF signal is changed by adjusting or attenuating the gain of the receiving module, and a detector is selected instead of a detection diode for power detection, which solves the problem of nonlinear error of the diode and achieves linear response. The power comparison is performed by a comparison submodule, and the corresponding level is output to the control module. The power detection and power comparison can more stably and reliably adjust the gain of the receiving module to the first RF signal, avoid unstable gain adjustment caused by amplitude fluctuations, effectively reduce the influence of noise, and more comprehensively control the power of the second RF signal. The device has high resistance to noise and interference and can perform small signal detection.

[0122] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0123] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0124] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method.

[0125] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0126] In the description of the present application, “plurality” means two or more.

[0127] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0128] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0129] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A small signal detection circuit, characterized in that: It includes an amplitude adjustment module, a signal conversion module and a control module connected in sequence, and also includes a receiving module, wherein the input end of the amplitude adjustment module is connected to the first output end of the receiving module, the output end of the control module is connected to the control end of the receiving module, and the signal conversion module includes a detector and a comparison submodule connected in sequence; In the case where the receiving module receives a first radio frequency signal, the receiving module samples the first radio frequency signal to obtain a coupled signal and outputs it through the first output terminal; the amplitude adjustment module attenuates or amplifies the coupled signal to generate an adjustment signal; the detector performs power detection on the adjustment signal to generate a detection signal; the comparison submodule compares the detection signals to generate a comparison signal; the control module determines the power range of the first radio frequency signal according to the comparison signal, and generates a control signal to output to the control terminal of the receiving module; the receiving module is used to adjust the gain of the first radio frequency signal according to the control signal, and generate a second radio frequency signal to output it through the second output terminal.

2. The small signal detection circuit according to claim 1, characterized in that: The comparison submodule includes a first dual-way comparator and a second dual-way comparator; The first dual-path comparator includes a first comparison branch and a second comparison branch, the first comparison branch is provided with a first threshold, the second comparison branch is provided with a second threshold, the second dual-path comparator includes a third comparison branch and a fourth comparison branch, the third comparison branch is provided with a third threshold, and the fourth comparison branch is provided with a fourth threshold; The comparison signal includes a first comparison signal, a second comparison signal, a third comparison signal and a fourth comparison signal; When the comparison submodule receives the detection signal, the first comparison branch compares the power value corresponding to the detection signal with the first threshold value to generate the first comparison signal, the second comparison branch compares the power value corresponding to the detection signal with the second threshold value to generate the second comparison signal, the third comparison branch compares the power value corresponding to the detection signal with the third threshold value to generate the third comparison signal, and the fourth comparison branch compares the power value corresponding to the detection signal with the fourth threshold value to generate the fourth comparison signal.

3. The small signal detection circuit according to claim 2, characterized in that: The first threshold is -65dBm, the second threshold is -55dBm, the third threshold is -45dBm, and the fourth threshold is -35dBm.

4. The small signal detection circuit according to claim 3, characterized in that: The model of the detector is MW1861, and the model of the first dual-channel comparator and the second dual-channel comparator are SGM8745.

5. The small signal detection circuit according to claim 1, characterized in that: The signal conversion module further includes an equalizer, and the detector is connected to the amplitude adjustment module via the equalizer.

6. The small signal detection circuit according to claim 3, characterized in that: The control module is further used for: The power range of the first radio frequency signal is determined according to the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal, and the control signal corresponding to the power range is output.

7. The small signal detection circuit according to claim 1, characterized in that: The amplitude adjustment module includes a first attenuator, a first operational amplifier, a second attenuator and a second operational amplifier connected in sequence, the first attenuator and the second attenuator attenuate the coupled signal, and the first operational amplifier and the second operational amplifier amplify the coupled signal.

8. The small signal detection circuit according to claim 7, characterized in that: The models of the first attenuator and the second attenuator are IFA-03, and the models of the first operational amplifier and the second operational amplifier are ILA-0118C.

9. A small signal detection device, characterized in that: A small signal detection circuit as described in any one of claims 1 to 8 is provided.

10. A small signal detection method, characterized in that: Applied to the small signal detection circuit according to any one of claims 1 to 8, the signal detection circuit comprises an amplitude adjustment module, a signal conversion module and a control module connected in sequence, and also comprises a receiving module, the input end of the amplitude adjustment module is connected to the first output end of the receiving module, the output end of the control module is connected to the control end of the receiving module, the signal conversion module comprises a detector and a comparison submodule connected in sequence, and the method comprises: When the receiving module receives a first radio frequency signal, the first radio frequency signal is sampled by the receiving module to obtain a coupled signal, which is output through the first output terminal; Attenuating or amplifying the coupling signal by the amplitude adjustment module to generate an adjustment signal; Performing power detection on the adjustment signal by the detector to generate a detection signal; The detection signal is compared by the comparison submodule to generate a comparison signal; The control module determines the power range of the first RF signal according to the comparison signal, and generates a control signal to output to the control end of the receiving module. The receiving module is used to adjust the gain of the first RF signal according to the control signal, and generate a second RF signal to output through the second output end.

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