CN113595570A - Method and device for solving mirror image interference - Google Patents

Method and device for solving mirror image interference Download PDF

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CN113595570A
CN113595570A CN202110941934.5A CN202110941934A CN113595570A CN 113595570 A CN113595570 A CN 113595570A CN 202110941934 A CN202110941934 A CN 202110941934A CN 113595570 A CN113595570 A CN 113595570A
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刘学
付文良
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Shenzhen Kirisun Communications Co ltd
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Fujian Kirisun Communications Co ltd
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
    • H04B1/1027—Means associated with receiver for limiting or suppressing noise or interference assessing signal quality or detecting noise/interference for the received signal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/26—Circuits for superheterodyne receivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
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    • H04B17/318—Received signal strength

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Abstract

The invention discloses a method and a device for solving mirror image interference. The image interference solution is used for a superheterodyne receiver or a superheterodyne receiver, and comprises the following steps: a signal receiving step: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal; a signal processing step: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times; wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency. The invention can better judge whether the image interference exists or not by changing the frequency of the local oscillator signal and comparing the mode of changing the RSSI values of the received signals before and after changing, thereby avoiding the image interference.

Description

Method and device for solving mirror image interference
Technical Field
The invention relates to the technical field of communication, in particular to a method and a device for solving image interference of a superheterodyne receiver or a superheterodyne receiver.
Background
The image interference is the interference specific to the superheterodyne receiver or the superheterodyne receiver, and is determined by the operating principle of the receiver. The existing superheterodyne receiver or superheterodyne receiver usually employs a band-pass filter and a band-stop filter to suppress image interference.
As shown in fig. 1, the conventional superheterodyne receiver including a Band pass Filter includes a Radio Frequency (RF) receiving antenna, a first Band Pass Filter (BPF), a Low Noise Amplifier (LNA), a second Band pass Filter, a mixer, a Channel selection Filter (Channel Filter), an Intermediate Frequency signal Amplifier (IFA or IF AMP), an Intermediate Frequency processing circuit (IF System), and a Local Oscillator (LO) connected to the mixer, which are connected in sequence. The receiver employs a band-pass filter as an image filter for suppressing image interference.
However, the filter can theoretically provide only several tens of dB of rejection and cannot completely solve the problem of image interference.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a method and an apparatus for solving image interference for a superheterodyne receiver or a superheterodyne receiver, which are used to better solve the image interference problem.
The technical scheme adopted by the invention is as follows:
in a first aspect, a method for solving image interference is provided, where the method is used in a superheterodyne receiver or a superheterodyne receiver, and includes: a signal receiving step: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal; a signal processing step: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times; wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency.
In a possible implementation manner, the signal receiving step specifically includes: configuring a local oscillation signal of a receiver as a first frequency, and mixing the local oscillation signal of the first frequency with a radio frequency signal entering a radio frequency front end to obtain a first intermediate frequency signal; detecting the RSSI value of the first intermediate frequency signal, and if the current RSSI value is larger than a threshold value, recording the current RSSI value as the RSSIlow(ii) a Reconfiguring local oscillator frequency of receiverThe local oscillator signal of the second frequency is mixed with the radio frequency signal entering the radio frequency front end to obtain a second intermediate frequency signal; detecting the RSSI value of the second intermediate frequency signal, and if the current RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh(ii) a Wherein the second frequency is higher than the first frequency.
In a possible implementation manner, the signal processing step specifically includes:
determine | RSSILOw-RSSIhighIf the | is smaller than a set value, receiving the current radio frequency signal if the | is smaller than the set value; and if not, judging that the mirror image interference exists.
In one possible implementation, the first frequency is denoted as LO, the frequency of the radio frequency signal desired to be received is RF ═ LO + IF, and IF is the frequency of the mixed intermediate frequency signal; then, the second frequency is LO' ═ LO +2 IF.
In one possible implementation, the method further includes: when judging that the image interference exists, further comparing the RSSIlowAnd RSSIhigh(ii) a If RSSIlowGreater than RSSIhighReturning to the signal receiving step, and mixing the local oscillator signal with the second frequency with the radio frequency signal entering the radio frequency front end in the signal receiving step to obtain a corresponding intermediate frequency signal; if RSSIlowLess than RSSIhighAnd returning to the signal receiving step, and mixing the local oscillator signal with the first frequency with the radio-frequency signal entering the radio-frequency front end in the signal receiving step to obtain a corresponding intermediate-frequency signal.
In one possible implementation, the superheterodyne receiver includes: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit; the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
In a second aspect, an image disturbance solving apparatus is provided for a superheterodyne receiver or a superheterodyne receiver, including: a signal receiving module for: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal; a signal processing module to: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times; wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency.
In one possible implementation, the signal receiving module is specifically configured to: configuring a local oscillation signal of a receiver as a first frequency, and mixing the local oscillation signal of the first frequency with a radio frequency signal entering a radio frequency front end to obtain a first intermediate frequency signal; detecting the RSSI value of the first intermediate frequency signal, and if the current RSSI value is larger than a threshold value, recording the current RSSI value as the RSSIlow(ii) a The second high frequency of the local oscillation frequency of the receiver is configured again, and the local oscillation signal of the second frequency is mixed with the radio frequency signal entering the radio frequency front end to obtain a second intermediate frequency signal; detecting the RSSI value of the second intermediate frequency signal, and if the current RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh(ii) a Wherein the second frequency is higher than the first frequency.
In a possible implementation manner, the signal processing module is specifically configured to: determine | RSSILOw-RSSIhighIf the | is smaller than a set value, receiving the current radio frequency signal if the | is smaller than the set value; and if not, judging that the mirror image interference exists.
In one possible implementation, the first frequency is denoted as LO, the frequency of the radio frequency signal desired to be received is RF ═ LO + IF, and IF is the frequency of the mixed intermediate frequency signal; then, the second frequency is LO' ═ LO +2 IF.
In one possible implementation, the signal processing module is further configured to: when judging that the image interference exists, further comparing the RSSIlowAnd RSSIhigh(ii) a If RSSIlowGreater than RSSIhighIf so, instructing the signal receiving module to adopt a local oscillator signal with a second frequency to mix with the radio frequency signal entering the radio frequency front end to obtain a corresponding intermediate frequency signal; if it is notRSSIlowLess than RSSIhighAnd instructing the signal receiving module to adopt a local oscillator signal with a first frequency to mix with the radio frequency signal entering the radio frequency front end to obtain a corresponding intermediate frequency signal.
In one possible implementation, the superheterodyne receiver includes: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit; the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
According to the technical scheme, the embodiment of the invention has the following advantages:
the invention can better judge whether the image interference exists or not by changing the frequency of the local oscillator signal and comparing the mode of changing the RSSI values of the received signals before and after changing, thereby avoiding the image interference.
In a further implementation mode of the invention, the superheterodyne receiver or the superheterodyne receiver which is suitable for the method can omit an image filter, thereby simplifying the structure of a hardware circuit, reducing the cost of the hardware circuit and being beneficial to reducing the noise coefficient of the circuit so as to improve the sensitivity.
Drawings
In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following briefly introduces the embodiment and the drawings used in the description of the prior art.
Fig. 1 is a schematic structural diagram of a conventional superheterodyne receiver;
FIG. 2 is a schematic diagram of the image disturbance generation principle;
fig. 3 is a schematic structural diagram of a superheterodyne receiver according to an embodiment of the present invention;
FIG. 4 is a flowchart illustrating a method for image disturbance resolution according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of an image disturbance solving apparatus according to an embodiment of the present invention.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The terms "first," "second," "third," and the like in the description and in the claims, and in the above-described drawings, are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.
The embodiment of the invention provides a method for solving the mirror image interference, which can thoroughly solve the problem of the mirror image interference of a superheterodyne receiver or a superheterodyne receiver by identifying and avoiding the mirror image interference.
For the understanding of the present invention, the principle of generating image interference is first introduced, and then the technical solution of the present invention is introduced. The following is a detailed description.
Firstly, the image interference generation principle:
let the Radio Frequency (RF) signal to be received be expressed as:
S(t)＝Acos(2πfRFt)
in the above formula, A is the signal amplitude, fRFIs the frequency of the radio frequency signal, i.e., the radio frequency.
Note that the Local Oscillator (LO) signal expression of the receiver is:
SLo(t)＝cos(2πfLot)
in the above formula fLoIs the frequency of the local oscillator signal, i.e. the local oscillator frequency of the local oscillator.
In a superheterodyne/superheterodyne receiver, an Intermediate Frequency (IF) signal is obtained by multiplying a local oscillation signal by an actual transmission signal, and a mathematical expression is as follows:
Figure BDA0003215395410000041
Figure BDA0003215395410000051
the difference frequency part is an intermediate frequency signal, namely:
cos(2πfRFt-2πfLot)＝cos(2π(fRF-fLo)t)
wherein, note fIFThe frequency of the intermediate frequency signal, i.e. the intermediate frequency, then has fIF＝(fRF-fLo)。
For convenience of description, the intermediate frequency is denoted by IF, the radio frequency by RF, and the local oscillator frequency by LO hereinafter.
Referring to fig. 2, it can be seen from the expression of the intermediate frequency signal that IF signals with the same frequency can be obtained through IF-RF-LO or IF-LO-RF when RF is higher or lower than LO with the same frequency.
When the local oscillator is designed to be low, i.e. the local oscillator frequency LO is lower than the reception RF frequency RF, the reception RF frequency is assumed to be RFHIGH. However, if there is a radio frequency signal at the frequency RFLOW, RFHIGH-LO ═ LO-RFLOW, the signal will also mix with LO and get an intermediate frequency signal at the same frequency, causing interference. This phenomenon is called image disturbance.
Similarly, when the received signal is designed to be a high local oscillator, that is, the local oscillator frequency LO is higher than the received radio frequency RF, the received signal is regarded as RFLOW. However, if there is a radio frequency signal at the frequency RFHIGH, and RFHIGH-LO is LO-RFLOW, the signal will also mix with LO and get an intermediate frequency signal at the same frequency, thereby causing interference. This phenomenon is also known as image disturbance.
For example, assuming that the desired received RF is 650KHz and the LO is 500KHz, the frequency IF of the intermediate frequency signal obtained by mixing the two is 150 KHz; however, mixing the 350KHZ RF signal with the LO signal also results in an intermediate frequency signal at the same frequency, i.e., 150KHz, which causes interference. With 500KHz as the center, 650KHz and 350KHz are mirror images of each other, and therefore, the interference of 350KHz is called mirror image interference or mirror image frequency interference.
Similarly, when the received RF is expected to be 350KHz, 650KHz interference constitutes image interference.
The working principle of the invention is as follows:
the embodiment of the invention can realize the image frequency interference suppression through the matching change of hardware and software:
(1) BPF circuits before and after an LNA are cancelled on hardware, circuit noise is reduced, and receiving sensitivity is improved;
(1) and determining whether the interference is mirror image interference and avoiding the interference by switching high and low local oscillator receiving and matching with the RSSI signal strength judgment mode on software.
Thirdly, the receiver of the embodiment of the invention:
the receiver of the embodiment of the invention can remove the BPF before the LNA, so that the image interference and the radio frequency signal expected to be received can directly enter the LNA and the mixer.
As shown in fig. 3, the superheterodyne receiver according to the embodiment of the present invention may include: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit; the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
Fourth, the image interference solution method of the embodiment of the invention
Referring to fig. 4, the method for solving the image interference according to the embodiment of the present invention may include the following steps:
s0, configuring a receiving circuit to wait for receiving signals;
s1, configuring the local oscillator frequency to be a low local oscillator (i.e., a first frequency LO), and when a signal with a desired receiving frequency RF being LO + IF is received (LO-IF is image interference), mixing the local oscillator frequency LO of the receiver with the radio frequency signal entering the radio frequency front end to obtain a corresponding intermediate frequency signal. Detecting the RSSI value of the intermediate frequency signal, and if the RSSI value is less than a threshold value (no signal), returning to the step of configuring a receiving circuit to wait for receiving the signal; if the RSSI value is larger than the threshold value (signal exists), recording the current RSSI value as the RSSIlowIt is not yet possible to distinguish between the wanted signal LO + IF and the image disturbance signal LO-IF.
S2, the local oscillator frequency is configured to be a high local oscillator (i.e., the second frequency LO' ═ LO +2IF), and the local oscillator frequency LO +2IF of the receiver is mixed with the rf signal entering the rf front end, so as to obtain a corresponding intermediate frequency signal. At this time, the image disturbance is LO +3 IF. Detecting the RSSI value of the intermediate frequency signal, and if the RSSI value is less than a threshold value (no signal), returning to the step of configuring a receiving circuit to wait for receiving the signal; if the RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh。
And S3, judging whether image interference exists, and whether the signal is received or ignored according to the RSSI values of the intermediate frequency signal obtained twice. Specifically, the | RSSI can be determinedlow-RSSIhighIf | is less than the set value. The set value may be set to 10dB, for example (theoretically, the RSSI value of the same received signal should be equal regardless of the local oscillator, but considering the signal variation between the time difference before and after, the difference between 10dB (empirical value) is considered to be the same signal). If the signal is less than 10dB, receiving the current signal, and returning to the configuration receiving circuit to wait for receiving the signal after the signal is finished; otherwise, judging the signal as an image interference signal, and returning to the step of configuring a receiving circuit to wait for receiving the signal.
It can be easily seen that, in the above step, RSSIlowIs the RSSI value of the desired received frequency LO + IF and its image interference frequency LO-IF at low local oscillatorForming; while RSSIhighIs composed of the RSSI value of the desired received frequency LO + IF and its image interference frequency LO +3IF at high local oscillator.
In reality, it is very rare that interference signals exist at the same time at LO-IF and LO +3IF (and RSSI values of the two interference signals are close), and the situation can be ignored.
RSSI assuming no interference at both LO-IF and LO +3IFlowAnd RSSIhighThe two signals are the same or similar, and the difference between the two signals does not exceed the set value determined by experience, in this case, no matter the local oscillator frequency is configured to be low Local Oscillator (LO) or high local oscillator (LO +2IF), the radio frequency signal can be correctly received.
RSSI assuming interference is present only at LO-IF, or only at LO +3IFlowAnd RSSIhighThere is a large difference. By comparing the difference value with a set value, whether mirror image interference exists can be easily judged. When there is image interference, the current radio frequency signal may be ignored and the process returns to configure the receiver circuit to wait for the received signal.
Optionally, when there is image interference, it may be further determined that image interference exists at that frequency.
If RSSIlowGreater than RSSIhighIF the difference value between the two is greater than the set value, the interference existing in the LO-IF can be judged; then, by configuring the local oscillator frequency to be high local oscillator (LO +2IF), the interference of LO-IF can be avoided;
if RSSIlowLess than RSSIhighIF the difference value between the two is greater than the set value, the interference existing in LO +3IF can be judged; then, by configuring the local oscillator frequency to be a low Local Oscillator (LO), the interference of LO +3IF can be avoided.
Fifth, the image interference solving device of the embodiment of the invention
Referring to fig. 5, an embodiment of the present invention further provides an image disturbance solving apparatus, where the apparatus is used in a superheterodyne receiver or a superheterodyne receiver, and the apparatus includes:
a signal receiving module 51, configured to: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal;
a signal processing module 52 for: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times;
wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency.
Optionally, the signal receiving module 51 is specifically configured to:
configuring a local oscillation signal of a receiver as a first frequency, and mixing the local oscillation signal of the first frequency with a radio frequency signal entering a radio frequency front end to obtain a first intermediate frequency signal; detecting the RSSI value of the first intermediate frequency signal, and if the current RSSI value is larger than a threshold value, recording the current RSSI value as the RSSIlow；
The second high frequency of the local oscillation frequency of the receiver is configured again, and the local oscillation signal of the second frequency is mixed with the radio frequency signal entering the radio frequency front end to obtain a second intermediate frequency signal; detecting the RSSI value of the second intermediate frequency signal, and if the current RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh；
Wherein the second frequency is higher than the first frequency.
Optionally, the signal processing module 52 is specifically configured to:
determine | RSSILOw-RSSIhighIf the | is smaller than a set value, receiving the current radio frequency signal if the | is smaller than the set value; and if not, judging that the mirror image interference exists.
Further, the first frequency is denoted as LO, the frequency of the radio frequency signal desired to be received is RF ═ LO + IF, and IF is the frequency of the mixed intermediate frequency signal; then, the second frequency is LO' ═ LO +2 IF.
Optionally, the superheterodyne receiver includes: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit; the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
In summary, the present invention discloses a method and an apparatus for solving image interference in a superheterodyne receiver or a superheterodyne receiver, which are used to better solve the image interference problem. By adopting the technical scheme, the embodiment of the invention has the following advantages:
the invention can better judge whether the image interference exists or not by changing the frequency of the local oscillator signal and comparing the mode of changing the RSSI values of the received signals before and after changing, thereby avoiding the image interference.
In a further implementation mode of the invention, the superheterodyne receiver or the superheterodyne receiver which is suitable for the method can omit an image filter, thereby simplifying the structure of a hardware circuit, reducing the cost of the hardware circuit and being beneficial to reducing the noise coefficient of the circuit so as to improve the sensitivity.
The technical solution of the present invention is explained in detail by the specific embodiments above. In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.
It should be understood that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; the technical solutions described in the above embodiments can be modified or part of the technical features can be equivalently replaced by those skilled in the art; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the spirit and the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. An image disturbance solution for a superheterodyne receiver or a superheterodyne receiver, comprising:
a signal receiving step: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal;
a signal processing step: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times;
wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency.
2. The method according to claim 1, wherein the signal receiving step specifically comprises:
configuring a local oscillation signal of a receiver as a first frequency, and mixing the local oscillation signal of the first frequency with a radio frequency signal entering a radio frequency front end to obtain a first intermediate frequency signal; detecting the RSSI value of the first intermediate frequency signal, and if the current RSSI value is larger than a threshold value, recording the current RSSI value as the RSSIlow；
The local oscillation frequency of the receiver is configured to be a second frequency again, and the local oscillation signal of the second frequency is mixed with the radio frequency signal entering the radio frequency front end to obtain a second intermediate frequency signal; detecting the RSSI value of the second intermediate frequency signal, and if the current RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh；
Wherein the second frequency is higher than the first frequency.
3. The method according to claim 2, characterized in that the signal processing step comprises in particular:
determine | RSSILow-RSSIhighIf the | is smaller than a set value, receiving the current radio frequency signal if the | is smaller than the set value; and if not, judging that the mirror image interference exists.
4. The method of claim 3,
the first frequency is noted as LO, the frequency of the radio frequency signal expected to be received is RF ═ LO + IF, and IF is the frequency of the mixed intermediate frequency signal;
then, the second frequency is LO' ═ LO +2 IF.
5. The method according to any one of claims 1 to 4,
the superheterodyne receiver includes: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit;
the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
6. An image disturbance solution apparatus for a superheterodyne receiver or a superheterodyne receiver, comprising:
a signal receiving module for: sequentially adopting local oscillator signals of a first frequency and a second frequency to mix with a radio frequency signal entering a radio frequency front end to obtain a corresponding intermediate frequency signal;
a signal processing module to: judging whether mirror image interference exists according to the RSSI values of the intermediate frequency signals obtained in the previous and subsequent times;
wherein the frequency of the radio frequency signal expected to be received is between the first frequency and the second frequency.
7. The apparatus of claim 6, wherein the signal receiving module is specifically configured to:
configuring a local oscillation signal of a receiver as a first frequency, and mixing the local oscillation signal of the first frequency with a radio frequency signal entering a radio frequency front end to obtain a first intermediate frequency signal; detecting the RSSI value of the first intermediate frequency signal, and if the current RSSI value is larger than a threshold value, recording the current RSSI value as the RSSIlow；
The second high frequency of the local oscillation frequency of the receiver is configured again, and the local oscillation signal of the second frequency is mixed with the radio frequency signal entering the radio frequency front end to obtain a second intermediate frequency signal; detecting the RSSI value of the second intermediate frequency signal, and if the current RSSI value is larger than the threshold value, recording the current RSSI value as the RSSIhigh；
Wherein the second frequency is higher than the first frequency.
8. The apparatus of claim 7, wherein the signal processing module is specifically configured to:
determine | RSSILow-RSSIhighIf the | is smaller than a set value, receiving the current radio frequency signal if the | is smaller than the set value; and if not, judging that the mirror image interference exists.
9. The apparatus of claim 8,
the first frequency is noted as LO, the frequency of the radio frequency signal expected to be received is RF ═ LO + IF, and IF is the frequency of the mixed intermediate frequency signal;
then, the second frequency is LO' ═ LO +2 IF.
10. The apparatus according to any one of claims 6 to 9,
the superheterodyne receiver includes: the radio frequency receiving antenna, the low noise amplifier, the mixer, the local oscillator, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit;
the radio frequency receiving antenna is directly connected with the low-noise amplifier, the low-noise amplifier is directly connected with the mixer, the local oscillator is connected with the mixer, and the mixer, the channel selection filter, the intermediate frequency signal amplifier and the intermediate frequency processing circuit are sequentially connected.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109541307A (en) * 2019-01-10 2019-03-29 上海创远仪器技术股份有限公司 The circuit structure of UWB signal analysis function is realized based on Single Conversion technology
CN109995387A (en) * 2019-03-01 2019-07-09 电子科技大学 A kind of method that broadband receiver inhibits Image interference
CN110336604A (en) * 2019-04-23 2019-10-15 电子科技大学 The terahertz signal blind-detection system of image frequency is distinguished by becoming local oscillator mode

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109541307A (en) * 2019-01-10 2019-03-29 上海创远仪器技术股份有限公司 The circuit structure of UWB signal analysis function is realized based on Single Conversion technology
CN109995387A (en) * 2019-03-01 2019-07-09 电子科技大学 A kind of method that broadband receiver inhibits Image interference
CN110336604A (en) * 2019-04-23 2019-10-15 电子科技大学 The terahertz signal blind-detection system of image frequency is distinguished by becoming local oscillator mode

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