CN111510174B - Method for realizing image frequency suppression processing aiming at first-stage superheterodyne receiver - Google Patents

Method for realizing image frequency suppression processing aiming at first-stage superheterodyne receiver Download PDF

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CN111510174B
CN111510174B CN202010317376.0A CN202010317376A CN111510174B CN 111510174 B CN111510174 B CN 111510174B CN 202010317376 A CN202010317376 A CN 202010317376A CN 111510174 B CN111510174 B CN 111510174B
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CN111510174A (en
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李栋
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Transcom Shanghai Technologies Co Ltd
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    • 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
    • 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
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Abstract

The invention relates to a method for realizing image frequency suppression processing aiming at a first-stage superheterodyne receiver, which comprises the steps of selecting different frequenciesIntermediate frequency signal If1And If2According to the intermediate frequency If1Setting initial local oscillator signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillator signal by mixer to obtain intermediate frequency signal If11(ii) a According to the sampling result of ADC, and intermediate frequency signal If1And If2Calculating to obtain corresponding amplitude An1And An2(ii) a Contrast amplitude An1And amplitude An2Storing the group of I-path data and Q-path data corresponding to the smaller amplitude value into a cache; and sequentially and circularly scanning all frequency points on the frequency band. The method for realizing image frequency suppression processing aiming at the first-stage superheterodyne receiver basically removes image frequency interference signals under the condition of using a first-stage frequency conversion receiver scheme, and has wide application range.

Description

Method for realizing image frequency suppression processing aiming at first-stage superheterodyne receiver
Technical Field
The invention relates to the technical field of communication, in particular to the field of image frequency suppression of a superheterodyne receiver, and specifically relates to a method for realizing image frequency suppression processing for a first-stage superheterodyne receiver.
Background
In most communication systems, a superheterodyne receiver scheme is used, in which a locally generated oscillation signal of adjustable frequency is used to mix a received radio frequency signal by a suitable mixer, and the radio frequency signal is converted to an intermediate frequency of a fixed frequency. Many out-of-tolerance receivers use multi-stage mixing and adding filters or a plurality of parallel mixers to suppress image frequency by means of phase shifting and adding, etc., but in some design schemes, designers have to use a one-stage single mixer low-intermediate frequency out-of-tolerance receiver scheme because of many limitations such as circuit complexity or power, etc., and image interference is inevitably generated at a receiving end.
The invention provides an image frequency suppression method based on a first-stage single mixer superheterodyne receiver scheme.
In general, in a single downconversion superheterodyne receiver scheme as shown in fig. 1, Rf is a receiver input signal, Lo is a local oscillation signal generated inside the receiver, Mixer is a Mixer, If is a fixed intermediate frequency signal of the receiver, where If is Lo-Rf (Lo > Rf), Filter is an anti-aliasing Filter at a front end of an ADC, and the ADC is a sampling processing circuit.
It is assumed here that Rf is an unknown single tone signal (which may also be a bandwidth)A signal). The receiver scans Rf with a continuously varying local oscillator Lo signal. When the local oscillator signal changes to Lo-Rf + If, the Mixer generates the intermediate frequency signal f of the desired frequency of the systemiLo-Rf, but when Lo-Rf-If, the Mixer can still generate an intermediate frequency signal f of frequency Rf-Lo-Ifm. At this time fm＝fiIn this case, the ADC and the anti-aliasing filter in front of the ADC cannot distinguish f at alliAnd fm. We call fm the image interference signal. Receiver scan results as in fig. 2, the expected scan results should be as shown in fig. 2(a), but the actual results are as shown in fig. 2(b) due to the presence of image interference.
The image interference signal cannot be removed basically in hardware by using a one-stage frequency conversion receiver scheme.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for realizing image frequency suppression processing aiming at a first-level superheterodyne receiver, which has the advantages of high accuracy, simple and convenient operation and wider application range.
In order to achieve the above object, the method for implementing image rejection processing for a first-stage superheterodyne receiver of the present invention is as follows:
the method for realizing image frequency suppression processing for the first-stage superheterodyne receiver is mainly characterized by comprising the following steps of:
(1) selecting intermediate frequency signals If of different frequencies1、If2According to the intermediate frequency If1、If2Setting initial local oscillator signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillator signal by mixer to obtain intermediate frequency signal If11、If12；
(2) According to the sampling result of ADC, and intermediate frequency signal If1And If2Calculating to obtain corresponding amplitude An1And An2；
(3) Contrast amplitude An1And amplitude An2Storing the group of I-path data and Q-path data corresponding to the smaller amplitude value into a cache;
(4) and (4) sequentially circulating the steps (1) to (3), sequentially scanning all frequency points on the frequency band, wherein the cached amplitude is data which can inhibit the mirror frequency interference.
Preferably, the step (2) specifically comprises the following steps:
(2.1) obtaining the sampling result of ADC, and using the intermediate frequency signal If1Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.2) calculating according to the I path data and the Q path data to obtain the amplitude An1；
(2.3) according to the intermediate frequency If2Setting local oscillation signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillation signal by mixer to obtain intermediate frequency signal If12；
(2.4) obtaining the sampling result of ADC, and using the intermediate frequency signal If2Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.5) calculating according to the I path data and the Q path data to obtain the amplitude An2。
Preferably, the method further comprises the steps of:
(5) uploading data to an upper computer to display a frequency spectrum curve, and adjusting If according to a display result and the suppression degree of the mirror frequency interference1And If2The higher degree of suppression at the RBW value is obtained.
Preferably, the digital processing in step (2.1) and step (2.4) specifically includes the following processing procedures:
and carrying out filtering processing, speed reduction processing and RBW filtering processing.
The method for realizing image frequency suppression processing aiming at the first-stage superheterodyne receiver obtains two frequency spectrograms by a method of changing intermediate frequency twice on the basis of the scheme of the first-stage single mixer superheterodyne receiver, can effectively identify and suppress image frequency interference signals by selecting two appropriate intermediate frequency signals and combining a digital low-pass filter and adopting a method of taking the minimum value, basically removes the image frequency interference signals under the condition of using the scheme of the first-stage frequency conversion receiver, and has wide application range.
Drawings
Fig. 1 is a diagram of a prior art single downconversion superheterodyne receiver scheme.
Fig. 2 is a diagram of a spectrum of an image interference signal generated using a one-stage frequency conversion receiver scheme according to the prior art.
Fig. 3 is a flowchart of a method for implementing image rejection processing for a first-stage superheterodyne receiver according to the present invention.
Fig. 4 is a schematic diagram of a signal processing procedure of the method for implementing image rejection processing for a first-stage superheterodyne receiver according to the present invention.
Fig. 5 is a schematic diagram of removing an image frequency interference signal according to the method for implementing image frequency suppression processing for a first-stage superheterodyne receiver of the present invention.
Fig. 6 is a schematic diagram of the image frequency interference suppression degree of the method for implementing image frequency suppression processing for the first-stage superheterodyne receiver according to the present invention.
Fig. 7 is a diagram of an actual result of image frequency interference in the embodiment of the method for implementing image frequency suppression processing for a first-stage superheterodyne receiver according to the present invention.
Fig. 8 is a diagram of an actual result of image rejection of the embodiment of the method for implementing image rejection processing for a first-stage superheterodyne receiver of the present invention.
Detailed Description
In order to more clearly describe the technical contents of the present invention, the following further description is given in conjunction with specific embodiments.
The method for realizing image frequency suppression processing aiming at the first-stage superheterodyne receiver comprises the following steps:
(1) selecting intermediate frequency signals If of different frequencies1、If2According to the intermediate frequency If1、If2Setting initial local oscillator signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillator signal by mixer to obtain intermediate frequency signal If11、If12；
(2) According to the sampling result of ADC, and intermediate frequency signal If1And If2Calculating to obtain corresponding amplitude An1And An2；
(3) Contrast amplitude An1And amplitude An2Storing the group of I-path data and Q-path data corresponding to the smaller amplitude value into a cache;
(4) and (4) sequentially circulating the steps (1) to (3), sequentially scanning all frequency points on the frequency band, wherein the cached amplitude is data which can inhibit the mirror frequency interference.
As a preferred embodiment of the present invention, the step (2) specifically comprises the following steps:
(2.1) obtaining the sampling result of ADC, and using the intermediate frequency signal If1Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.2) calculating according to the I path data and the Q path data to obtain the amplitude An1；
(2.3) according to the intermediate frequency If2Setting local oscillation signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillation signal by mixer to obtain intermediate frequency signal If12；
(2.4) obtaining the sampling result of ADC, and using the intermediate frequency signal If2Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.5) calculating according to the I path data and the Q path data to obtain the amplitude An2。
As a preferred embodiment of the present invention, the method further comprises the steps of:
(5) uploading data to an upper computer to display a frequency spectrum curve, and adjusting If according to a display result and the suppression degree of the mirror frequency interference1And If2The higher degree of suppression at the RBW value is obtained.
As a preferred embodiment of the present invention, the digital processing in step (2.1) and step (2.4) specifically includes the following processing procedures:
and carrying out filtering processing, speed reduction processing and RBW filtering processing.
In the specific implementation mode of the invention, two signals are obtained by a method of changing intermediate frequency twice on the basis of a scheme of a first-stage single-mixer superheterodyne receiverFor the two spectrograms shown in FIG. 2(b), the image interference is at Rf-2 Xif1And Rf-2 If2The result of the signal with energy actually existing at Rf is the same in the two sampling processes, and the image frequency interference signal can be effectively identified and suppressed by selecting the appropriate two intermediate frequency signals and combining the two intermediate frequency signals with the digital low-pass filter by adopting the method of taking the minimum value. The invention has the following steps.
Setting receiver scan band [ Rfstar，Rfstop]In this frequency band, a useful signal Rf is present.
The method comprises the following steps: selecting intermediate frequency signals If of two different frequencies according to system characteristics1And If2. If as much as possible1And If2The sum frequency difference is larger because then the spectral overlap of the image frequency interference is relatively small even at large RBWs.
Step two: with If1Scanning frequency band [ Rf ] as intermediate frequency signalstar，Rfstop]And the first frequency point Rf1 is digitally processed by ADC sampling to obtain the usage If1As an amplitude point a11 of the spectrogram curve of the intermediate frequency signal.
Step three: with If2Scanning frequency band [ Rf ] as intermediate frequency signalstar，Rfstop]And Rf1 is digitally processed through ADC sampling to obtain the usage If2As an amplitude point a12 of the spectrogram curve of the intermediate frequency signal.
The digital processing in the second step and the third step is as shown in fig. 4, after receiving data from the ADC, the DSP first multiplies two digital local oscillator signals with a phase difference of 90 ° generated inside to obtain IQ two zero intermediate frequency signals, and then performs filtering and speed reduction processing to obtain accurate BW passband I and Q signals, respectively. The square of the re-passing amplitude value
Figure GDA0003360244400000041
Step four: comparing the sizes of A11 and A12, and keeping the I and Q values corresponding to the smaller values, and storing the I and Q values in a system amplitude-frequency buffer area.
Step five: the step two to the step four are circulated until the frequency band [ Rfstar，Rfstop]All frequency points in the medium frequency band use two intermediate frequencies If1And If2The scan is complete.
Finally, we obtain a group of frequency bands [ Rf ] in the system amplitude-frequency buffer areastar，Rfstop]The amplitude and frequency values of the group are plotted, and then the amplitude and frequency values are plotted in a graph of Rf-2 x If1And Rf-2 If2The image interference at the center is suppressed.
For convenience of explanation and comparison, the intermediate frequency If is adopted1Obtaining an amplitude-frequency diagram as shown in fig. 4(a) during frequency sweeping, and adopting an intermediate frequency If2An amplitude-frequency diagram obtained during frequency sweeping is shown in fig. 5(b), and an amplitude-frequency diagram obtained after processing by the method from the second step to the fifth step is shown in fig. 5 (d).
By selecting the appropriate If, as in FIG. 5(a)1、If2The combined RBW can effectively suppress image frequency interference. Selecting If1、If2Is determined according to the degree of suppression of the image-frequency interference. At specified RBW ═ FbwFirst, it is obtained at FbwThe attenuation degree at different frequency offsets at the lower relative central frequency point Rf is shown in fig. 6:
attenuation of 3dB at frequency offset of 5kHz and 30dB at frequency offset of 50kHz, If as shown in FIG. 6(a)1And If2The image frequency interference is suppressed by 3dB If the phase difference is 10kHz, If the phase difference is in the same range, the image frequency interference is suppressed by 3dB1And If2The image frequency interference is suppressed by 30dB If the difference is 100kHz, If more suppression is needed, If the If is continuously pulled open1And If2The difference in frequency is sufficient. Until the selected intermediate frequency is outside the passband of the ADC pre-anti-aliasing filter or limited by other factors, etc.
The specific implementation software flow is shown in fig. 3:
step 1: according to the 1 st intermediate frequency If1Setting the initial 1 st local oscillator frequency with the initial frequency of the scanning frequency band, and mixing the received radio frequency signal and the local oscillator signal by a mixer to obtain an intermediate frequency signal If11。
Step 2: starting ADC, obtaining ADC sampling result using digital local oscillator (frequency and If)1Same) down-conversion to obtain I and Q path data, then filtering, speed reduction, RBW filtering and the likeAnd (6) performing digital processing.
And 3, step 3: obtaining the amplitude An of the I, Q data obtained after the digital filtering processing according to the I, Q data1。
And 4, step 4: according to the 2 nd intermediate frequency If2Setting the initial 1 st local oscillator frequency with the initial frequency of the scanning frequency band, and mixing the received radio frequency signal and the local oscillator signal by a mixer to obtain an intermediate frequency signal If12。
And 5, step 5: starting ADC, obtaining ADC sampling result using digital local oscillator (frequency and If)2Same) down-conversion to obtain I and Q paths of data, and then carrying out digital processing such as filtering, speed reduction, RBW filtering and the like.
And 6, step 6: obtaining the amplitude An of the I, Q data obtained after the digital filtering processing according to the I, Q data2。
And 7, step 7: comparison of An1And An2And storing the group of I and Q values corresponding to the smaller amplitude value into a buffer memory.
And 8, step 8: and (4) circulating the steps 1 to 7, sequentially scanning all frequency points on the frequency band, and storing a group of I and Q values in a cache after the scanning is finished, wherein the group of I and Q values are data which can inhibit the mirror frequency interference.
Step 9: the data are uploaded to an upper computer to display a spectrum curve, and the obtained result is shown in fig. 7.
Step 10: if can be adjusted according to the display result and the suppression degree of the mirror frequency interference1And If2The value of (c) obtains a higher degree of suppression at the RBW value.
In this embodiment, the system Rf input signal is 50MHz, RBW is 100Hz, power is-42 dBm, the spectrum result is shown in fig. 7 when no image frequency suppression is adopted, and image frequency interference is at 54.66666 MHz. The power of which is consistent with the actual signal power.
It can be seen that the image interference is suppressed by 59.2dB or more. The invention only adopts a one-time frequency conversion superheterodyne receiver, and realizes the suppression of the mirror frequency interference on the basis of less hardware cost.
The method for realizing image frequency suppression processing aiming at the first-stage superheterodyne receiver obtains two frequency spectrograms by a method of changing intermediate frequency twice on the basis of the scheme of the first-stage single mixer superheterodyne receiver, can effectively identify and suppress image frequency interference signals by selecting two appropriate intermediate frequency signals and combining a digital low-pass filter and adopting a method of taking the minimum value, basically removes the image frequency interference signals under the condition of using the scheme of the first-stage frequency conversion receiver, and has wide application range.
In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims (3)

1. A method for realizing image frequency suppression processing aiming at a first-stage superheterodyne receiver is characterized by comprising the following steps:
(1) selecting different frequencies If of the intermediate frequency signal1、If2According to the intermediate frequency If1、If2Setting initial local oscillator signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillator signal by mixer to obtain intermediate frequency signal If11、If12；
(2) Calculating to obtain corresponding amplitude An according to the sampling result of the ADC on the intermediate frequency signal1And An2；
(3) Contrast amplitude An1And amplitude An2Storing the group of I-path data and Q-path data corresponding to the smaller amplitude value into a cache;
(4) sequentially circulating the step (1) to the step (3), sequentially scanning all frequency points on the frequency band, wherein the cached amplitude is data which can inhibit the mirror frequency interference;
the method further comprises the following steps:
(5) uploading data to an upper computer to display a frequency spectrum curve, and adjusting If according to a display result and the suppression degree of the mirror frequency interference1And If2The value of (c).
2. The method for implementing image rejection processing for a first-order superheterodyne receiver according to claim 1, wherein the step (2) specifically includes the steps of:
(2.1) obtaining the sampling result of ADC by using intermediate frequency signal If11Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.2) calculating according to the I path data and the Q path data to obtain the amplitude An1；
(2.3) according to the intermediate frequency If2Setting local oscillation signal with initial frequency of scanning frequency band, mixing received radio frequency signal and local oscillation signal by mixer to obtain intermediate frequency signal If12；
(2.4) obtaining the sampling result of the ADC by using the IF signal If12Performing down-conversion on the digital local oscillators with the same frequency to obtain I-path data and Q-path data, and performing digital processing;
(2.5) calculating according to the I path data and the Q path data to obtain the amplitude An2。
3. The method for implementing image rejection processing for a first-order superheterodyne receiver according to claim 2, wherein the digital processing in step (2.1) and step (2.4) specifically includes the following processing procedures:
and carrying out filtering processing and speed reduction processing.
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JP4061504B2 (en) * 2004-04-12 2008-03-19 ソニー株式会社 Receiver and receiving IC
CN100426686C (en) * 2005-06-01 2008-10-15 鼎芯通讯（上海）有限公司 Low mid frequency wireless receiver of automatic calibration circuit with image suppression
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US9407490B2 (en) * 2014-12-23 2016-08-02 Intel Corporation Method of processing received digitized signals and mobile radio communication terminal device
CN109995387B (en) * 2019-03-01 2021-03-30 电子科技大学 Method for inhibiting image interference of broadband receiver
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