WO2015172303A1

WO2015172303A1 - Receiver mirror image calibrating method, device and base station

Info

Publication number: WO2015172303A1
Application number: PCT/CN2014/077300
Authority: WO
Inventors: 叶四清; 李建平; 武杰; 李兴文
Original assignee: 华为技术有限公司
Priority date: 2014-05-12
Filing date: 2014-05-12
Publication date: 2015-11-19
Also published as: CN105264780A; CN105264780B

Abstract

Provided in an embodiment of the present invention are a receiver mirror image calibrating method, device and base station, the method comprising: inputting into a receiver by an injection module a service signal inputted from the service signal end of the injection module and a bandwidth test signal inputted from the test signal end of the injection module; demodulating the inputted service signal and the bandwidth test signal, and outputting I and Q paths of baseband analog signals; conducting analog-digital conversion on the I and Q paths of baseband analog signals to obtain I and Q paths of baseband digital signals; and conducting digital calibration on the I and Q paths of baseband digital signals to eliminate the mirror image distortion of the receiver. The embodiment of the present invention reduces test time, and improves the efficiency of testing the mirror image distortion of the full spectrum band of a receiver, thus timely and effectively calibrating the mirror image distortion of the receiver.

Description

Receiver image correction method, device and base station

Technical field

The embodiments of the present invention relate to communication technologies, and in particular, to a receiver image correction method, apparatus, and base station.

BACKGROUND OF THE INVENTION Due to the inherent circuit characteristics of a receiver, there is inevitably a problem of amplitude and phase imbalance of the I/Q channel in the receiver. The amplitude and phase imbalance of the I/Q channel may cause image distortion of the spectrum of the two signals of I and Q, thereby affecting The quality of communication to the wireless link.

The image correction method generally used in the prior art is to send the single tone signal outputted by the phase locked loop circuit to the quadrature demodulation receiver, and the quadrature demodulation receiver demodulates the I under the action of the receiver local oscillator module. And Q two baseband analog signals, and the analog-to-digital converter converts the I and Q baseband analog signals into two baseband digital signals of I and Q, and digitally corrects the two baseband digital signals of I and Q. However, using this method to test the image distortion in the entire bandwidth of the receiver is problematic in that it takes a long time and has low efficiency, so that the image distortion of the receiver cannot be corrected in time and effectively. SUMMARY OF THE INVENTION Embodiments of the present invention provide a method, a device, and a base station for correcting a receiver image, so as to solve the problem that the image distortion in the entire bandwidth of the receiver is tested in the prior art, which is time-consuming and inefficient, thereby achieving The image distortion of the receiver is corrected in time and effectively.

In a first aspect, an embodiment of the present invention provides a receiver image correcting apparatus, including: an injection module, a receiver, an analog-to-digital conversion circuit, and a digital correction circuit;

The injection module is configured to input a service signal input from a service signal end of the injection module and a broadband test signal input from a test signal end of the injection module into the receiver through an injection module;

The receiver is configured to demodulate the input service signal and the broadband test signal and output two baseband analog signals of I and Q;

The analog-to-digital conversion circuit is configured to perform analog-to-digital conversion on the two baseband analog signals of the I and Q to obtain two baseband digital signals of I and Q; The digital correction circuit is configured to digitally correct the two baseband digital signals of the I and Q to eliminate image distortion of the receiver.

In a first possible implementation manner of the first aspect, the broadband test signal is generated by using a switching modulation circuit to pulse modulate a single tone signal under the action of a pulse signal.

According to a first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the spectrum of the broadband test signal is a position that is obtained by setting a frequency spectrum of the pulse signal from a center frequency to 0. Moved to a position where the center frequency is the negative frequency and the positive frequency of the tone signal, respectively.

According to the first or second possible implementation of the first aspect, in the third possible implementation of the first aspect, the tone signal is generated by a phase locked loop circuit or a direct synthesis circuit, the lock An output of the phase loop circuit or the direct synthesis circuit is coupled to a first input of the switch modulation circuit, the pulse signal being generated by a pulse signal generation circuit.

According to the first or second possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the tone signal is generated by a transmitter local oscillator module, An output end of the vibration module is coupled to the first input end of the switch modulation circuit, and the pulse signal is generated by a pulse signal generation circuit.

According to the first or second possible implementation of the first aspect, in a fifth possible implementation of the first aspect,

The tone signal is generated by a receiver local oscillator module, and an output end of the receiver local oscillator module is connected to a first input end of the switch modulation circuit, and the pulse signal is generated by a pulse signal generating circuit.

In a sixth possible implementation manner of the first aspect, the output end of the pulse signal generating circuit is a second input end of the switching modulation circuit is connected, an output end of the switching modulation circuit is connected to a test signal end of the injection module, and an output end of the injection module is connected to a first input end of the receiver. The second input end of the receiver is connected to the output end of the receiver local oscillator module, and the output end of the receiver is connected to the first input end of the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is a first input end of the digital correction circuit is connected, an input end of the pulse signal generating circuit, a second input end of the analog to digital conversion circuit, and a second input end of the digital correction circuit are respectively associated with a digital clock circuit The output is connected. According to the first aspect, in a seventh possible implementation manner of the first aspect, the broadband test signal is generated by a pulse signal generating circuit;

An output end of the switch modulation circuit is connected to a test signal end of the injection module, an output end of the injection module is connected to a first input end of the receiver, and a second input end of the receiver is connected to a receiver An output end of the local oscillator module is connected, an output end of the receiver is connected to a first input end of the analog to digital conversion circuit, and an output end of the analog to digital conversion circuit is connected to a first input end of the digital correction circuit The input end of the pulse signal generating circuit, the second input end of the analog to digital conversion circuit, and the second input end of the digital correction circuit are respectively connected to an output end of the digital clock circuit.

According to the first aspect, any one of the possible implementation manners of the first to seventh possible implementations of the first aspect, in the eighth possible implementation manner of the first aspect, And performing periodic accumulation of the two baseband digital signals of the I and Q to improve a signal to noise ratio of the broadband test signal; calculating a mirror correction coefficient according to the broadband test signal with improved signal to noise ratio; correcting according to the image The coefficients are digitally corrected for the I and Q baseband digital signals to eliminate image distortion of the receiver.

According to the first aspect, any one of the first to the eighth possible implementation manners of the first aspect, in the ninth possible implementation manner, the injection module comprises a switch, a coupler or a resistor network.

In a second aspect, an embodiment of the present invention provides a base station, comprising the receiver image correcting apparatus according to any one of the preceding claims.

In a third aspect, an embodiment of the present invention provides a receiver image correction method, including: passing a service signal input from a service signal end of an injection module and a broadband test signal input from a test signal end of the injection module through the injection Module input receiver;

Demodulating the input service signal and the broadband test signal and outputting two baseband analog signals of I and Q;

Performing analog-to-digital conversion on the two baseband analog signals of the I and Q to obtain two baseband digital signals of I and Q;

The baseband digital signals of the I and Q are digitally corrected to eliminate the mirror distortion of the receiver.

In a first possible implementation manner of the third aspect, the broadband test signal is generated by using a switch modulation circuit to pulse modulate a single tone signal under the action of a pulse signal.

According to a first possible implementation of the third aspect, the second possible implementation in the third aspect In the present mode, the spectrum of the broadband test signal is obtained by moving the spectrum of the pulse signal from a position having a center frequency of 0 to a position where the center frequency is a negative frequency and a positive frequency of the tone signal.

According to a first or second possible implementation of the third aspect, in a third possible implementation of the third aspect,

The single tone signal is generated by a phase locked loop circuit or a direct synthesis circuit, and an output end of the phase locked loop circuit or the direct synthesis circuit is connected to a first input end of the switch modulation circuit, and the pulse signal is a pulse signal. Generated by the circuit.

According to the first or second possible implementation of the third aspect, in a fourth possible implementation of the third aspect,

The tone signal is generated by a transmitter local oscillator module, and an output end of the transmitter local oscillator module is connected to a first input end of the switch modulation circuit, and the pulse signal is generated by a pulse signal generating circuit.

According to the first or second possible implementation of the third aspect, in a fifth possible implementation of the third aspect,

In a sixth possible implementation manner of the third aspect, the output end of the pulse signal generating circuit is a second input end of the switching modulation circuit is connected, an output end of the switching modulation circuit is connected to a test signal end of the injection module, and an output end of the injection module is connected to a first input end of the receiver. The second input end of the receiver is connected to the output end of the receiver local oscillator module, and the output end of the receiver is connected to the first input end of the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is a first input end of the digital correction circuit is connected, an input end of the pulse signal generating circuit, a second input end of the analog to digital conversion circuit, and a second input end of the digital correction circuit are respectively associated with a digital clock circuit The output is connected.

According to the third aspect, in a seventh possible implementation manner of the third aspect, the broadband test signal is generated by a pulse signal generating circuit;

An output end of the switch modulation circuit is connected to a test signal end of the injection module, and the note An output of the input module is coupled to the first input of the receiver, a second input of the receiver is coupled to an output of the receiver local oscillator module, and an output of the receiver and the analog to digital converter a first input end of the circuit is connected, an output end of the analog to digital conversion circuit is connected to a first input end of the digital correction circuit, an input end of the pulse signal generating circuit, and a second input of the analog to digital conversion circuit And a second input of the digital correction circuit is coupled to an output of the digital clock circuit.

According to the third aspect, any one of the first to seventh possible implementation manners of the third aspect, in the eighth possible implementation manner of the third aspect, Digital correction of digital signals, including:

And using the digital correction circuit to periodically accumulate the two baseband digital signals of the I and Q to improve the signal to noise ratio of the broadband test signal;

Calculating the image correction coefficient by using the digital correction circuit according to the broadband test signal with improved signal to noise ratio;

And performing, by the digital correction circuit, digitally correcting the two baseband digital signals of the I and Q according to the image correction coefficient to eliminate image distortion of the receiver.

According to the third aspect, the first to the eighth possible implementation manner of the third aspect, in the ninth possible implementation manner of the third aspect, the injection module comprises a switch, a coupler or a resistor The internet.

In the embodiment of the present invention, a receiver image correction method, apparatus, and base station, by inputting a service signal and a broadband test signal into a receiver through an injection module, demodulate an input service signal and a broadband test signal, and output two baseband analogs of I and Q. The signal is subjected to analog-to-digital conversion of the two baseband analog signals of I and Q to obtain two baseband digital signals of I and Q, and digitally corrects the two baseband digital signals of I and Q to eliminate the image distortion of the receiver. Thereby reducing the test time, improving the efficiency of the image distortion of the full-band of the test receiver, and realizing timely and effective correction of the image distortion of the receiver. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings to be used in the embodiments or the description of the prior art will be briefly described below, and obviously, in the following description The drawings are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

FIG. 1 is a mirror image correction for performing image correction on a receiver according to Embodiment 1 of the present invention. a circuit diagram of device 100;

2 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 2 of the present invention;

3 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 3 of the present invention;

4 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 4 of the present invention;

5 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 5 of the present invention;

6 is a flowchart of a receiver image correction method according to Embodiment 6 of the present invention; FIG. 7A is a flowchart of a receiver image correction method according to Embodiment 7 of the present invention; FIGS. 7B-7D are respectively an embodiment of the present invention; Time domain waveform diagrams of the single tone signal, pulse signal and broadband test signal provided by the seven;

7E-7G are rough views of the frequency spectrums of the tone signal, the pulse signal, and the broadband test signal according to Embodiment 7 of the present invention;

7H is a detailed view of the spectrum of the broadband test signal centered on FIG. 7G according to Embodiment 7 of the present invention;

71 is a frequency spectrum diagram of two baseband analog signals of I and Q which are demodulated and outputted by the receiver 5 by the broadband test signal centered on the ^^ in FIG. 7G according to Embodiment 7 of the present invention;

FIG. 7J is a schematic diagram showing the cyclic accumulation of two baseband digital signals of I and Q according to Embodiment 7 of the present invention. The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. The embodiments are a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

FIG. 1 is a circuit diagram of a mirror correction apparatus 100 for performing image correction on a receiver according to Embodiment 1 of the present invention. The apparatus of this embodiment is adapted to mirror loss in the bandwidth of the receiver Really correct the situation. The device is typically implemented in hardware and/or software. Referring to FIG. 1, the apparatus includes: an injection module 110, a receiver 120, an analog to digital conversion circuit 130, and a digital correction circuit 140.

The injection module 110 is configured to input a service signal input from the service signal end of the injection module 110 and a broadband test signal input from the test signal end of the injection module 110 into the receiver through the injection module; the receiver 120 is configured to input the service signal and The broadband test signal is demodulated and outputs two baseband analog signals of I and Q; the analog-to-digital conversion circuit 130 is used for analog-to-digital conversion of the two baseband analog signals of I and Q to obtain two baseband digital signals of I and Q; The correction circuit 140 is used for digitally correcting the two baseband digital signals of I and Q to eliminate the image distortion of the receiver.

It should be noted that the function of the injection module is to combine the service signal and the broadband test signal into one signal input receiver, and the injection module can be integrated in the receiver.

Specifically, the digital correction circuit 140 is specifically configured to periodically accumulate the baseband digital signals of the I and Q to improve the signal-to-noise ratio of the broadband test signal, and calculate the image correction coefficient according to the broadband test signal with improved signal-to-noise ratio, according to The image correction coefficient is digitally corrected for the two baseband digital signals of I and Q to eliminate the image distortion of the receiver.

Further, the broadband test signal is generated by using a switching modulation circuit to modulate a single tone signal under the action of a pulse signal.

Further, the spectrum of the wideband test signal can be obtained by moving the spectrum of the pulse signal from the position of the center frequency to 0 to the position where the center frequency is the negative frequency and the positive frequency of the tone signal.

Further, the single tone signal may be generated by a phase locked loop circuit or a direct synthesis circuit, and the output end of the phase locked loop circuit or the direct synthesis circuit is connected to the first input end of the switch modulation circuit, and the pulse signal is generated by the pulse signal generation circuit. of.

It should be noted that the phase-locked loop circuit is further divided into an analog phase-locked loop circuit and a digital phase-locked loop circuit. The direct synthesis circuit is further divided into a direct analog synthesizer (DAS) circuit and a direct digital synthesis (Direct Digital Synthesizer). , referred to as DDS) circuit. Currently, digital phase-locked loops and direct digital synthesis are used more.

Optionally, the single tone signal may be generated by the transmitter local oscillator module, and the output end of the transmitter local oscillator module is connected to the first input end of the switch modulation circuit, and the pulse signal is generated by the pulse signal generating circuit. Optionally, the tone signal is generated by the receiver local oscillator module, and the output end of the receiver local oscillator module is connected to the first input end of the switch modulation circuit, and the pulse signal is generated by the pulse signal generation circuit.

Further, the output end of the pulse signal generating circuit is connected to the second input end of the switch modulation circuit, and the output end of the switch modulation circuit is connected to the test signal end of the injection module, and the output end of the injection module and the first input end of the receiver Connected, the second input of the receiver is connected to the output of the receiver local oscillator module, the output of the receiver is connected to the first input of the analog-to-digital conversion circuit, and the output of the analog-to-digital conversion circuit and the digital correction circuit are An input terminal is coupled to the input of the pulse signal generating circuit, the second input of the analog to digital conversion circuit, and the second input of the digital correction circuit to the output of the digital clock circuit.

Optionally, the broadband test signal is generated by the pulse signal generating circuit;

The output end of the switching modulation circuit is connected to the test signal end of the injection module, the output end of the injection module is connected to the first input end of the receiver, and the second input end of the receiver is connected to the output end of the receiver local oscillator module, the receiver The output end is connected to the first input end of the analog-to-digital conversion circuit, the output end of the analog-to-digital conversion circuit is connected to the first input end of the digital correction circuit, the input end of the pulse signal generating circuit, and the second input end of the analog-to-digital conversion circuit And a second input of the digital correction circuit is coupled to the output of the digital clock circuit, respectively.

Further, the injection module can be a switch, a coupler or a resistor network.

The receiver image correcting apparatus provided in this embodiment adopts a service signal and a broadband test signal to be input into a receiver by using an injection module, demodulates an input service signal and a broadband test signal, and outputs two baseband analog signals of I and Q, The I and Q baseband analog signals are analog-to-digital converted to obtain two baseband digital signals of I and Q, and digitally correct the two baseband digital signals of I and Q to eliminate the image distortion of the receiver. Thereby reducing the test time, improving the efficiency of the image distortion of the full-band of the test receiver, and realizing timely and effective correction of the image distortion of the receiver.

The process of mirror correction of the receiver will be described below with reference to FIG. 2, FIG. 3, FIG. 4 and FIG. 2 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 2 of the present invention. Referring to FIG. 2, an output end of the phase locked loop circuit 1 is connected to a first input end of the switch modulation circuit 2, and is pulsed. An output end of the signal generating circuit 3 is connected to a second input end of the switching modulation circuit 2, an output end of the switching modulation circuit 2 is connected to a test signal end of the injection module 4, and an output end of the injection module 4 and a first input of the receiver 5 The second input end of the receiver 5 is connected to the output end of the receiver local oscillator module 6, and the output end of the receiver 5 is connected to the first input end of the analog-to-digital conversion circuit 7, The output of the analog-to-digital conversion circuit 7 is connected to the first input terminal of the digital correction circuit 8, the input terminal of the pulse signal generating circuit 3, the second input terminal of the analog-to-digital conversion circuit 7, and the second input terminal of the digital correction circuit 8 respectively It is connected to the output of the digital clock circuit 9. As shown in FIG. 2, the pulse signal generated by the pulse signal generating circuit 3 is input to the switching modulation circuit 2. The single tone signal generated by the phase locked loop circuit 1 is also input to the switching modulation circuit 2, and the switching modulation circuit 2 uses the input pulse signal to the tone. The signal is modulated to generate a broadband test signal input injection module 4, and the service signal is input from the service signal end of the injection module 4 to the injection module 4. The injection module 4 can input the input service signal and the broadband test signal to the receiver 5, due to the injection. The broadband test signal input to the receiver 5 by the module 4 is a broadband test signal obtained by the switch modulation circuit 2 modulating the single tone signal generated by the phase locked loop circuit 1 by using the pulse signal generated by the pulse signal generating circuit 3, and can cover the receiver. The full frequency band thus reduces the time for testing the full-band image distortion of the receiver, improves the efficiency of the image distortion of the full-band of the test receiver, and achieves timely and effective correction of the image distortion of the receiver. The receiver 5 demodulates the input service signal and the broadband test signal under the action of the receiver local oscillator module 6 and outputs two baseband analog signals of I and Q to the analog to digital conversion circuit 7, and the analog to digital conversion circuit 7 inputs the input I and Q two baseband analog signals are analog-to-digital converted to obtain two baseband digital signals of I and Q, and the analog-to-digital conversion circuit 7 outputs two baseband digital signals of I and Q to the digital correction circuit 8 pairs of I and Q baseband digital signals The signal is digitally corrected to eliminate image distortion from the receiver.

It should be noted that the phase-locked loop circuit 1 can be replaced by a direct synthesis circuit, and the connection relationship after replacement by the direct synthesis circuit is the same as that of FIG. 2, and details are not described herein again.

3 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 3 of the present invention. Referring to FIG. 3, the circuit diagram shown in FIG. 3 is substantially the same as the circuit diagram shown in FIG. 2, and thus is not shown. The connection relationship between the switching modulation circuit 2, the analog-to-digital conversion circuit 7, and the digital correction circuit 8 and the digital clock circuit 9. The difference is that the phase-locked loop circuit 1 shown in FIG. 1 is replaced by a transmitter local oscillator module 10, and the output of the transmitter local oscillator module 10 is connected to the first input of the switch-modulating circuit 2. That is, the transmitter local oscillator module 10 is used to generate a tone signal and the tone signal is input to the switch modulation circuit 2. The switch modulation circuit 2 uses the pulse signal input from the pulse signal generation circuit 3 to input the tone signal to the transmitter local oscillator module 10. Modulation is performed to generate a wideband test signal. Since the phase-locked loop circuit is not used to generate a tone signal, not only the function of the circuit diagram shown in FIG. 2 but also the system cost can be saved. It should be noted that the other output end of the transmitter local oscillator module 10 can be connected to the second input end of the transmitter 11, and the first input end of the transmitter 11 and the output of the digital-to-analog conversion circuit 12 The end connection, the signal output from the output end of the transmitter 11 is sent to the duplexer 13, and the duplexer 13 transmits the received downlink service signal to the space through the antenna 19, and the uplink service signal and the switching modulation circuit output by the duplexer 13 The output broadband test signal is sent to the injection module 4, and the injection module 4 gates or mixes the uplink service signal and the broadband test signal, and then outputs the signal to the receiver 5.

4 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 4 of the present invention. Referring to FIG. 4, the circuit diagram shown in FIG. 4 is substantially the same as the circuit diagram shown in FIG. 2, and thus is not shown. The connection relationship between the switching modulation circuit 2, the analog-to-digital conversion circuit 7, and the digital correction circuit 8 and the digital clock circuit 9. The difference is that the receiver local oscillator module 14 is used instead of the phase locked loop circuit 1 shown in Fig. 2, and the output terminal of the receiver local oscillator module 14 is connected to the first input terminal of the switching modulation circuit 2. That is, the receiver local oscillator module 14 is used to generate a tone signal and the tone signal is input to the switch modulation circuit 2. The switch modulation circuit 2 uses the pulse signal input from the pulse signal generation circuit 3 to input the tone signal to the receiver local oscillator module 14. Modulation is performed to generate a wideband test signal. Since the phase-locked loop circuit is not used to generate a tone signal, not only the function of the circuit diagram shown in FIG. 2 but also the system cost can be saved. The first input of the transmitter 17 is connected to the output of the transmitter local oscillator module 21, the second input of the transmitter 17 is connected to the output of the digital-to-analog conversion circuit 22, and the input of the digital-to-analog conversion circuit 22 is digital pre- The output of the distortion circuit 23 is connected, and the input of the digital predistortion circuit 23 is connected to the output of the digital correction circuit. And since the signal output from the transmitter 17 is divided into two paths, a signal which is generally not less than 99% of the total power is sent to the duplexer 18, and then transmitted to the space through the antenna 20. Only the signal which generally does not exceed 1% of the total power is sent to the injection module via the coupler, and the signal which generally does not exceed 1% of the total power is referred to as a feedback signal, that is, the feedback signal is input as a service signal to the injection module 4. The injection module 4 can gate or mix the feedback signal and the wideband test signal output from the switching modulation circuit 2, and then output the signal to the receiver 5. It should be noted that the other output end of the receiver local oscillator module 14 can be connected to the second input end of the receiver 15, and the first input end of the receiver 15 receives the uplink service signal output by the duplexer 18, and the receiver 15 The output terminal is connected to the input terminal of the analog-to-digital conversion circuit 16, and the output terminal of the analog-to-digital conversion circuit 16 outputs an uplink service signal.

5 is a circuit diagram of a mirror correction device for performing image correction on a receiver according to Embodiment 5 of the present invention. Referring to FIG. 5, the circuit diagram shown in FIG. 5 is basically the same as the circuit diagram shown in FIG. 2, and the difference is that a pulse signal is used. The pulse signal generated by the generating circuit 24 is used as the broadband test signal of the input injection module 4. Since the pulse signal is a wideband spectrum, its high-order harmonics fall into the radio frequency band of the receiver 5, so it can also be used as a signal for the input injection module 4. Other principles and technical effects and diagrams The same in 2, will not be described here.

FIG. 6 is a flowchart of a receiver image correction method according to Embodiment 6 of the present invention. The method of this embodiment is applicable to the case of correcting image distortion in the bandwidth of the receiver. The method is performed by a receiver image correction device, which is typically implemented in hardware and/or software. The method of this embodiment includes the following steps:

610. Input a service signal input from a service signal end of the injection module and a broadband test signal input from a test signal end of the injection module into the receiver through the injection module.

In the prior art, since the frequency of the phase-locked loop circuit needs to be replaced multiple times, it takes a long time to test the image distortion in the bandwidth of the entire receiver. Since the input receiver is a wideband test signal, it can test the image distortion in the entire bandwidth of the receiver at one time to correct the I and Q signals of the receiver output, thereby eliminating the image distortion of the receiver. .

620. Demodulate the input service signal and the broadband test signal and output two baseband analog signals of I and Q.

630. Perform analog-to-digital conversion on the I and Q baseband analog signals to obtain two baseband digital signals of I and Q.

640. Digitally correct the two baseband digital signals of I and Q to eliminate the mirror distortion of the receiver.

Specifically, the service signal and the broadband test signal are input into the receiver through the injection module, the input service signal and the broadband test signal are demodulated, and the I and Q baseband analog signals are output, and the I and Q baseband analog signals are simulated. The signal is analog-to-digital converted to obtain two baseband digital signals of I and Q, and digitally corrects the two baseband digital signals of I and Q to eliminate the image distortion of the receiver.

The receiver image correction method provided in this embodiment demodulates the input service signal and the broadband test signal by outputting the service signal and the broadband test signal into the receiver through the injection module, and outputs two baseband analog signals of I and Q, The I and Q baseband analog signals are analog-to-digital converted to obtain two baseband digital signals of I and Q, and digitally correct the two baseband digital signals of I and Q to eliminate the image distortion of the receiver. Thereby reducing the test time, improving the efficiency of the image distortion of the full-band of the test receiver, and realizing timely and effective correction of the image distortion of the receiver.

This embodiment is optimized based on the above-mentioned sixth embodiment, and FIG. 7A is the present invention. A flowchart of a receiver image correction method provided in Embodiment 7. Referring to FIG. 7A, the method in this embodiment may include:

710. Input a service signal input from a service signal end of the injection module and a broadband test signal input from a test signal end of the injection module into the receiver through the injection module.

The generation of the broadband test signal can be achieved as follows:

For example, the wideband test signal is generated by using a switching modulation circuit to modulate a single tone signal under the action of a pulse signal. The single tone signal and the pulse signal can be generated in the following three ways: One way is that the single tone signal can be generated by a phase locked loop circuit or a direct synthesis circuit, and the output and switching modulation of the phase locked loop circuit or the direct synthesis circuit The first input of the circuit is connected, and the pulse signal is generated by the pulse signal generating circuit. In another method, the single tone signal is generated by the transmitter local oscillator module, and the output end of the transmitter local oscillator module is connected to the first input end of the switch modulation circuit, and the pulse signal is generated by the pulse signal generating circuit. In another method, the single tone signal is generated by the receiver local oscillator module, and the output end of the receiver local oscillator module is connected to the first input end of the switch modulation circuit, and the pulse signal is generated by the pulse signal generating circuit.

To facilitate the understanding of the present invention, only the time domain waveform and the frequency domain waveform of the tone signal, the pulse signal, and the broadband test signal are described in conjunction with FIGS. 7B-7G. FIGS. 7B-7D are respectively the tone provided by the seventh embodiment of the present invention. A time domain waveform diagram of the signal, the pulse signal, and the broadband test signal, and FIGS. 7E-7G are rough views of the spectrum of the tone signal, the pulse signal, and the broadband test signal provided in Embodiment 7 of the present invention, respectively. Referring to FIG. 7E, in the frequency domain, the single tone signal is a single spectral line, and the frequency is as shown in FIG. 7F. Since the pulse signal generated by the pulse signal generating circuit is a periodic signal in the time domain, the spectrum is a discrete plurality of spectral lines. wherein the spectrum is 0 Flanagan strongest line, we call the main line, line intervals w, the switching cycle of the switching modulation of the modulation circuit, a first frequency spectrum is the position ^ ⁷ ^ 0, the second spectral frequency position 0 for ^ ⁷ ^, and so on, 7 is valid switch modulator; see FIG. 7G, the spectrum broadband test signals, etc. Thus the spectrum of the pulse signal from the center frequency position 0, At the same time, the position shifted to the center frequency is -, and the position where the center frequency is ^, we call the spectrum shifted to the position of the frequency as the negative side spectrum, and the spectrum shifted to the position where the frequency is the positive side spectrum, the frequency is - The main lines of ^", are called the negative side spectrum main line and the positive side spectrum main line, respectively.

In the implementation manner of each of the single tone signal and the pulse signal, the output end of the pulse signal generating circuit is connected to the second input end of the switch modulation circuit, and the output end of the switch modulation circuit and the injection module The test signal terminal is connected, the output end of the injection module is connected to the first input end of the receiver, the second input end of the receiver is connected to the output end of the receiver local oscillator module, and the output end of the receiver is connected to the analog-to-digital conversion circuit. The first input terminal is connected, the output end of the analog-to-digital conversion circuit is connected to the first input end of the digital correction circuit, the input end of the pulse signal generating circuit, the second input end of the analog-to-digital conversion circuit, and the second input end of the digital correction circuit Connected to the output of the digital clock circuit.

The generation of broadband test signals can also be achieved as follows:

For example, the broadband test signal is generated by the pulse signal generating circuit, the output end of the switch modulation circuit is connected to the test signal end of the injection module, the output end of the injection module is connected to the first input end of the receiver, and the second output of the receiver The input end is connected to the output end of the receiver local oscillator module, the output end of the receiver is connected to the first input end of the analog to digital conversion circuit, and the output end of the analog to digital conversion circuit is connected to the first input end of the digital correction circuit, the pulse signal An input of the generating circuit, a second input of the analog to digital conversion circuit, and a second input of the digital correction circuit are coupled to the output of the digital clock circuit, respectively. Wherein, the single tone signal, the pulse signal and the signal outputted by the output end of the receiver local oscillator module are phase-locked to the same reference clock source, and the reference clock source is a reference clock signal outputted from the output end of the digital clock circuit, thereby A strict relative phase relationship is maintained between the tone signal, the pulse signal, and the signal output from the output of the receiver local oscillator module.

It should be noted that the injection module in this embodiment may be a switch, a coupler or a resistor network. The injection module may gate or mix the service signal and the broadband test signal, and then input the gated or mixed signal to the receiver, where the receiver may be a quadrature demodulation receiver that receives the uplink service signal of the base station or It is a quadrature demodulation feedback receiver for transmitter predistortion correction.

720. Demodulate the input service signal and the broadband test signal and output two baseband analog signals of I and Q.

The spectrum of the two baseband analog signals of I and Q is described below with reference to FIG. 7H. FIG. 7H is a detailed diagram of the spectrum of the broadband test signal centered on FIG. 7G according to Embodiment 7 of the present invention, FIG. 7H. The aliased portion of the mirrored spectrum is shown in the detailed view shown. In Fig. 7G, because the graph is too small and inconvenient, the aliasing portion of the mirrored spectrum is not shown. Referring to Fig. 7H, the thin line in Fig. 7H indicates positive The side spectrum, the thick line indicates the tail of the negative side spectrum. The thin line and the thick line are only to distinguish the positive side and the negative side spectrum, and do not indicate the spectrum strength. The spectrum strength is represented by the line height.

If the positive side spectrum of the broadband test signal is moved to the baseband, the spectrum of the two baseband analog signals obtained by I and Q is as shown in FIG. 71, and FIG. 71 is provided in FIG. 7G according to Embodiment 7 of the present invention. of. The central broadband test signal is demodulated by the receiver 5 and output the spectrum of the two baseband analog signals of the I and Q. Figure 71 also contains the aliasing of the image spectrum. Figure 71 can be seen as moving the Figure 7H from the RF frequency position with the center frequency of /„ _fo to the baseband frequency position centered at 0.

730. Analog-to-digital conversion is performed on the two baseband analog signals of I and Q by using an analog-to-digital conversion circuit to obtain two baseband digital signals of I and Q.

740. Using a digital correction circuit to periodically accumulate the two baseband digital signals of I and Q to improve the signal to noise ratio of the broadband test signal.

Since the broadband test signal input to the receiver is a periodic signal, and the digital clock circuit, the phase-locked loop circuit and the receiver local oscillator module are coherent, the phase signals of each period can be completely the same. In this way, when the period is accumulated, the phases of the signals of the respective periods are completely the same, so that the in-phase addition of the periodic signals between different periods is realized. Coherent means phase-locked to the same reference clock source, thus maintaining a strict relative phase relationship between the three signals.

The following describes the key technical parameters of the wideband test signal as a periodic signal in combination with equations (1) ~ (5):

The period of the wideband test signal referred to herein is not the switching signal period of the time length r _sw but the period of the baseband signal which is input to the digital correction circuit 8 of FIG. 2 for the period accumulation, that is, the period of the period accumulation. time length, containing samples _∞ points. From the formula below, we can see that ^ is different from ⁷ ^.

T _acc = N _acc *T _s , is a positive integer (1) where ⁷ ^ is Figure 2, which is the ADC sampling point interval in the basic block diagram of the present invention, and the sampling frequency is: =丄

(2) If the receiver 5 moves the positive side spectrum of the wideband test signal to the baseband, the spectrum of the two baseband analog signals obtained by I and Q is as shown in Fig. 71. The parameters related to the spectrum of Figure 71 are as follows:

Remember

(3) =丄

Y- (4) indicates the local oscillator offset. It means the frequency of the tone signal and the frequency of the signal output from the output of the receiver's local oscillator module. The difference in frequency between. L represents the frequency of the pulse signal, that is, the line spacing of the pulse signal.

The two baseband analog signals of I and Q behave as complex signals in the form of I+jQ, and the spectrum of the two baseband analog signals of I and Q is obtained by Fourier transform of the complex signal of I+jQ form. The spectrum in Figure 7E shows the amplitude of the spectrum and does not represent the phase of the spectrum.

The line whose RF frequency is ^ ", that is, the main line in the positive side spectrum, at the receiver output, becomes the line of the frequency equal to, which is equal to ^"― ^/rf . Line of the spectrum. And the frequency is '. The RF frequency, the receiver local oscillator frequency, becomes zero at the receiver output.

It is preferable to make / _Was as small as possible so that the main spectrum of the spectrum of the two baseband analog signals of I and Q is as close as possible to the 0 frequency, so that the frequency domain power of the wideband test signal falls in the center of the receiving channel band of the receiver. , the receiver characteristics can be measured most efficiently.

Where the positive integer ^ in (1) should satisfy the following formula:

N—

GCD is the greatest common divisor. GCZ x y^) is defined to make GCZ x y^),

X

GCD{ _Xl , x ₂ ,...,x _N ) ^GCD ( -, ) are the largest positive numbers of integers. If there is no such positive number, then ^σα) ( ^χ ι, ^Χ 2,···, ) is defined as ο. For example, GCD(12,18)=6, GCD(12,15,18)=3, GCD(12,15,-18)=3, GCD(0.12,0.2)=0.04, GCD(l/3,l/ 4,l/5)=l/60 , GCD( V2 A/2 ) ₌ 2 , GCD(d8) is 0.

(5) means ^ ^ should be

Integer multiples _{(from which it is} known that (ie ^ ) is an integer multiple of T _sw (ie ^ ). This means a general ratio

T only satisfies the formula (5), and the digital clock circuit, the phase-locked loop circuit and the receiver local oscillator module are coherent, and the broadband test can be realized by adding the period of the digital baseband signal. The effective improvement of the SNR of the number.

The process of periodically accumulating the two baseband digital signals of I and Q using a digital correction circuit will be described below with reference to FIG. 7J. FIG. 7J is a schematic diagram of periodically accumulating two baseband digital signals of I and Q according to Embodiment 7 of the present invention. Assume that the wideband test signal period is M samples, and the baseband digital signal has a sequence length of N cycles, that is, N*M samples. The signal sequence of N*M samples is input to the periodic accumulator, and M samples are output. The detailed cycle accumulation process is as follows:

The first sample of the signal sequence + the M+1th sample + the 2*M+1 sample +···+ the (N-1)*M+1 samples are added as a period The first output sample; the second sample of the signal sequence + the M+2 sample + the 2*M+2 sample +···+ the first (Ν-1)*Μ+2 Sample, as the second output sample of the cycle accumulation; and so on, the Mth sample of the signal sequence + the 2*M samples + the 3*M samples +···+N* M samples, as the Mth output sample of the cycle accumulation.

In the prior art, since the frequency of the test signal needs to be continuously changed during the frequency sweeping of the entire bandwidth of the receiver, that is, the frequency of the phase-locked loop circuit that generates the test signal, and the phase-locked loop circuit replaces the frequency point each time. Both need a phase locking process, that is, there is a phase drift problem in the phase locking process, and it is impossible to use the period accumulation in the receiver, so only a large-bandwidth broadband test signal can be injected into the receiver to improve the I and Q baseband digital signals. Signal to noise ratio. In this embodiment, since the input receiver is a broadband test signal, since there is no need to change the frequency point, the phase of the test signal output by the receiver has no drift problem, so a small amplitude broadband test signal can be injected into the receiver, and then the cycle is adopted. Accumulate to improve the signal-to-noise ratio of the two baseband digital signals of I and Q.

The process of periodic accumulation is introduced in conjunction with FIG. 7E. FIG. 7E is a schematic diagram of periodic accumulation provided by Embodiment 7 of the present invention. Referring to FIG. 7E, since the input signal of the input receiver is a periodic signal, and the digital clock circuit, the phase-locked loop circuit and the receiver local oscillator module are coherent, the periodic signal of each period can be made. The phases are exactly the same, so that when the period is accumulated, the phases of the signals in each period are exactly the same, so that the in-phase addition of the periodic signals between different periods is realized, so that the amplitude increase multiple of the broadband test signal is equal to the cumulative period, due to the broadband The power multiplier of the test signal is the square of the multiple of the amplitude increase, thus greatly increasing the power of the wideband test signal. Taking the accumulation of 10 cycles as an example, the test signal power is increased by 100 times after the cycle accumulation. The service signal and noise are non-periodic signals, and the power multiplier is the power addition, that is, the power increase multiple is equal to the accumulation period, so after the accumulation of 10 cycles, the power of the traffic signal and the noise only grows to 10 Times. So after the accumulation, the test signal is relative to the business letter The power ratio of the number to the noise, that is, the signal-to-noise ratio of the test signal, is increased to 10 times before the accumulation.

750. Calculate the image correction coefficient by using a digital correction circuit according to the broadband test signal with improved signal to noise ratio.

760. According to the image correction coefficient, the digital correction circuit is used to digitally correct the two baseband digital signals of I and Q to eliminate the image distortion of the receiver.

In order to make the wideband test signal friendly to the digital correction of the two baseband digital signals of I and Q, it is necessary to satisfy the following formulas (6) and (7). Wherein, the spectrum of the broadband test signal is to satisfy the following formula

The expression (6) means that S^^ ⁷ ^ cannot be an integer. To make the broadband test signal spectrum satisfy the following formula

Mod(2f _rxlo T _sw ,l)≠0 (7)

The formula (7) means that it cannot be an integer.

The wideband test signal is completely friendly to the IQ image correction algorithm only if equations (6) and (7) are satisfied. This friendliness is not only friendly to the blind IQ image correction algorithm, but also friendly to the unblinded Q image correction algorithm. It is more critical to satisfy the formula (6). That is to say, if the formula (6) is not satisfied, the wideband test signal is very unfriendly to the IQ image correction algorithm. If (6) is satisfied and (7) is not satisfied, the wideband test signal is friendly to the IQ image correction algorithm, but it is not completely friendly. The wideband test signal is completely friendly to the IQ image correction algorithm only if both equations (6) and (7) are satisfied.

Wherein, the length of ^ is taken as an integer number of sampling points, that is, ^ satisfies the following formula (8):

m , 7V _W is a positive integer (8) The length of Γ shown in Figure 7C and Figure 7D is preferably taken as an integer number of sampling points to facilitate circuit implementation, ie

T _duty = N _duty T _s , N is a positive integer (9) Moreover, in order to make the spectral main lobe of the wideband test signal in Fig. 7D sufficiently wide, it is preferable to make N as small as possible. Generally take

N _duty = l (10) The main lobe of the spectrum here refers to the width between the two left and right 0 spectral points.

Saying "best" here means that this is not a mandatory requirement of the present invention. Just a recommendation. Failure to meet such requirements will not render the system inoperable, but performance may be lost.

The line whose RF frequency is ^〃, that is, the main line in the positive side spectrum, at the output of the receiver, becomes the line of the frequency equal to _∞ , which is equal to the line of "-/^. The frequency is The RF frequency, the receiver local oscillator frequency, becomes 0 at the receiver output.

Within the width of the main lobe of the spectrum, it is preferable to have a sufficiently large number of lines. Generally no less than 8. The positive frequency part is not less than 4, that is to say

N

£1L_ > 4

(11) How the formula (6) and the formula (7) are obtained are described below.

First, synthesize (2), (4), (8), get the formula (12) f =丄=^_ = (12)

^SW _sw N _SW T _S N _{sw is} well known in the industry. The broadband test signal that is friendly to the IQ image correction algorithm satisfies the following condition r _s , (T) = E{s(t)s(tT)} = 0, for any r ( 13) Represents the cross-correlation function with the signal. The argument of the function is the relative delay of the two signals. It can be positive, negative, and can be 0. Indicates a statistical average. For signals with cross-correlation functions with signals that have various states of traversal, the statistical average can be replaced by time averaging, that is, r _s , (τ) = E{s(t)s(tT)} = lim- \s(t )s(t -τ)ώ , for any τ (14)

^T→ T Here we assume the time span of [_Γ/2, Γ/2], that is, the time span. Definition by convolution

® s(-T) denotes the convolution of the sum, the _Fourier transform of 0, and the basic relationship of the _Fourier transform

S(f)S(-f) = F{ _S (T) _S (-T)}

F{} means Fourier. Combine the formula (13)~(16) to get the formula (17)

=0 When it is a periodic signal, ^s (is a discrete spectral line. The baseband injection signal is a periodic signal, so its spectrum ^S (is a discrete spectral line, referred to as the spectral line. (17) actually requires the baseband injection number After the spectrum is symmetrically transformed with respect to the 0 frequency, it is not aliased with the spectral line of the original spectrum.

Record the equivalent signal ^S with the baseband (the corresponding RF signal spectrum is ^(/ ), which is also a discrete spectral line, where the spectrum in the positive frequency band, ie / < J rxlo 2, J ^ΓΧ ^° 2 is recorded as positive In the frequency band, (17) is equivalent to lim S; _f (f)S (2f _rxlo -f) = 0 , f (18)

Equation (18) means the spectrum of the RF injected signal, including the positive side spectrum and the negative side spectrum, with respect to the receiver local oscillator frequency'. After the symmetric transformation, the spectral lines of the original spectrum are not aliased. This requirement, in terms of the spectrum of the baseband signal, can be equivalent to two conditions that are simultaneously established: Condition 1: The main line of the broadband test signal, that is, the line of the broadband test signal with the frequency, and the line of any positive side spectrum, including the main line with the test signal itself, are not symmetric about the 0 frequency. relationship.

As can be seen from Fig. 71, the frequency of the main line of the wideband test signal is Λ, . _∞ , and the line of any positive side spectrum, that is, the line in Fig. 71, can be expressed as / _Was + i Any integer, can be positive, negative, can be 0), so this requirement requires writing

Item 2: The main line of the broadband test signal and the line of any negative side spectrum are not related to the 0 frequency. As can be seen from Figure 71, the frequency of the main line of the wideband test signal is ^ «, and any negative side i The spectral line, that is, the thick line in Figure 71, can be expressed as (^ is an arbitrary integer, can be positive, negative, can be 0), one requirement is written into a mathematical formula

Here ^ is an arbitrary integer, which can be positive, negative, and 0 ₍

Can transform (19) into

2 (21) Obviously, the formula (21) is the formula (6).

Using equation (3), equation (20) can be transformed into

2 T _s m (22) Obviously, the formula (22) is the formula (7).

When (6) and (7) are simultaneously satisfied, it can be seen from the above derivation that the most primitive requirement of (13) is also satisfied.

That is to say, (13) is the original requirement of the broadband test signal which is friendly to the IQ image correction algorithm, and under the periodic signal, (6) and (7) are a clearer formula that can satisfy the formula (13). The circuit description below shows how the formula (5) is obtained.

The cycle time length of the period accumulating unit in the digital correction circuit is When the digital correction circuit is used to periodically accumulate the two baseband digital signals of I and Q, in order to realize the in-phase accumulation of the broadband test signals during the period, the phase of the broadband test signal should be the same at the beginning of each cycle. For this reason, the time domain signals corresponding to all the spectral line components in the wideband test signal in FIG. 7D should be made to be an integer number of cycles in the accumulation period, that is, the length of ⁷ ^^. For the positive side spectrum is:

Mod NT,, ,1 0 , for any integer (23)

For the negative side spectrum is

, 1 = 0, for any integer m (24)

The two requirements of (23) and (24) must be met at the same time ₍

Use equation (2) to deform equation (23) to mod = 0, for any integer (25)

If (25) is undoubtedly satisfied. That is, when

When η , ;7 is a positive integer (26), the formula (25) is undoubtedly satisfied.

■ξ , ξ is a positive integer (27)

Combine the formulas (26) and (27) to get the formula (28)

GCD GCD bias, GCD fbias + 2/„

N

ζ , is a positive integer (28) f _s /N _a GCD GCD f _blas + 2f _n

So formula (28) becomes

= c is a positive integer (30) It is not difficult to see that equation (30) is equation (5).

The receiver image correction method provided in this embodiment uses a service signal and a broadband test signal to be input to a receiver through an injection module, so that the receiver demodulates the input service signal and the broadband test signal and outputs the I and Q paths. The baseband analog signal uses an analog-to-digital conversion circuit to perform analog-to-digital conversion of the two baseband analog signals of I and Q to obtain two baseband digital signals of I and Q, and uses a digital correction circuit to periodically accumulate the two baseband digital signals of I and Q. Improve the signal-to-noise ratio of the broadband test signal. According to the wideband test signal with improved signal-to-noise ratio, the digital correction circuit is used to calculate the image correction coefficient. According to the image correction coefficient, the digital correction circuit is used to digitally correct the two baseband digital signals of I and Q. To eliminate the image distortion of the receiver. Thereby reducing the test time, improving the efficiency of the image distortion of the full-band of the test receiver, and realizing timely and effective correction of the image distortion of the receiver.

One of ordinary skill in the art will appreciate that all or a portion of implementing the various method embodiments described above can be accomplished by hardware associated with the program instructions. The aforementioned program can be stored in a computer readable storage medium. The program, when executed, performs the steps including the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting thereof; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

Claim

A receiver image correcting device, comprising: an injection module, a receiver, an analog to digital conversion circuit, and a digital correction circuit;

The analog-to-digital conversion circuit is configured to perform analog-to-digital conversion on the two baseband analog signals of the I and Q to obtain two baseband digital signals of I and Q;

The digital correction circuit is configured to digitally correct the two baseband digital signals of the I and Q to eliminate image distortion of the receiver.

2. The apparatus according to claim 1, wherein the wideband test signal is generated by pulse modulating a tone signal by a pulse modulation signal by a switch modulation circuit.

3. The apparatus according to claim 2, wherein the spectrum of the broadband test signal is moved by shifting a spectrum of the pulse signal from a position where the center frequency is 0 to a center frequency of the tone signal. Obtained at the position of the negative frequency and the positive frequency.

The device according to claim 2 or 3, wherein the single tone signal is generated by a phase locked loop circuit or a direct synthesis circuit, and an output end of the phase locked loop circuit or the direct synthesis circuit is A first input terminal of the switching modulation circuit is connected, and the pulse signal is generated by a pulse signal generating circuit.

The device according to claim 2 or 3, wherein the tone signal is generated by a transmitter local oscillator module, an output end of the transmitter local oscillator module and a first end of the switch modulation circuit The input terminal is connected, and the pulse signal is generated by a pulse signal generating circuit.

The device according to claim 2 or 3, wherein the tone signal is generated by a receiver local oscillator module, an output end of the receiver local oscillator module and a first end of the switch modulation circuit The input terminal is connected, and the pulse signal is generated by a pulse signal generating circuit.

The apparatus according to any one of claims 2 to 6, wherein an output end of the pulse signal generating circuit is connected to a second input end of the switch modulation circuit, and an output of the switch modulation circuit The end is connected to the test signal end of the injection module, and the output end of the injection module is a first input end of the receiver is connected, a second input end of the receiver is connected to an output end of the receiver local oscillator module, and an output end of the receiver is connected to the first input end of the analog to digital conversion circuit An output end of the analog-to-digital conversion circuit is coupled to a first input end of the digital correction circuit, an input end of the pulse signal generating circuit, a second input end of the analog-to-digital conversion circuit, and the digital correction circuit The second input is coupled to the output of the digital clock circuit.

8. The apparatus according to claim 1, wherein the wideband test signal is generated by a pulse signal generating circuit;

The apparatus according to any one of claims 1 to 8, wherein the digital correction circuit is specifically configured to periodically accumulate the two baseband digital signals of the I and Q to improve the broadband Signal-to-noise ratio of the test signal; calculating a mirror correction coefficient according to the broadband test signal with improved signal-to-noise ratio; digitally correcting the two baseband digital signals of the I and Q according to the image correction coefficient to eliminate the receiving The image of the machine is distorted.

10. Apparatus according to any one of claims 1 to 9, wherein the injection module comprises a switch, a coupler or a resistor network.

A base station, comprising: the image correcting device for a receiver according to any one of claims 1 to 10.

12. A receiver image correction method, comprising:

Transmitting a service signal input from a service signal end of the injection module and a broadband test signal input from a test signal end of the injection module into the receiver through the injection module;

Digitally correcting the I and Q baseband digital signals to eliminate the mirror of the receiver Like distortion.

13. The method according to claim 12, wherein the wideband test signal is generated by using a switch modulation circuit to pulse modulate a tone signal under the action of a pulse signal.

14. The method according to claim 13, wherein the spectrum of the broadband test signal is moved by moving the spectrum of the pulse signal from a position having a center frequency of 0 to a center frequency of the tone signal. Obtained at the position of the negative frequency and the positive frequency.

The method according to claim 13 or 14, wherein the tone signal is generated by a phase locked loop circuit or a direct synthesis circuit, and an output end of the phase locked loop circuit or the direct synthesis circuit is A first input terminal of the switching modulation circuit is connected, and the pulse signal is generated by a pulse signal generating circuit.

The method according to claim 13 or 14, wherein the tone signal is generated by a transmitter local oscillator module, and an output end of the transmitter local oscillator module and a first end of the switch modulation circuit The input terminal is connected, and the pulse signal is generated by a pulse signal generating circuit.

The method according to claim 13 or 14, wherein the tone signal is generated by a receiver local oscillator module, and an output end of the receiver local oscillator module and a first one of the switch modulation circuit The input terminal is connected, and the pulse signal is generated by a pulse signal generating circuit.

The method according to any one of claims 13 to 17, wherein an output end of the pulse signal generating circuit is connected to a second input end of the switch modulation circuit, and an output of the switch modulation circuit The end is connected to the test signal end of the injection module, the output end of the injection module is connected to the first input end of the receiver, and the second input end of the receiver is connected to the output end of the receiver local oscillator module The output end of the receiver is connected to the first input end of the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is connected to the first input end of the digital correction circuit, the pulse signal generating circuit The input terminal, the second input of the analog to digital conversion circuit, and the second input of the digital correction circuit are respectively coupled to the output of the digital clock circuit.

19. The method according to claim 12, wherein the broadband test signal is generated by a pulse signal generating circuit;

An output end of the switch modulation circuit is connected to a test signal end of the injection module, an output end of the injection module is connected to a first input end of the receiver, and a second input end of the receiver is connected to a receiver An output end of the local oscillator module is connected, an output end of the receiver is connected to a first input end of the analog-to-digital conversion circuit, an output end of the analog-to-digital conversion circuit and a first end of the digital correction circuit The input terminal is connected, and the input end of the pulse signal generating circuit, the second input end of the analog to digital conversion circuit, and the second input end of the digital correction circuit are respectively connected to an output end of the digital clock circuit.

The method according to any one of claims 12 to 19, wherein the digitally correcting the two baseband digital signals of the I and Q comprises:

The method according to any one of claims 12 to 20, wherein the injection module comprises a switch, a coupler or a resistor network.