A transceiver system

Abstract

This invention discloses a transceiver system comprising: a receiver, a transmitter, a digital calibration module, and a calibration loop; the receiver's RF front-end module is connected to the receiver's analog intermediate frequency (IF) module; the digital calibration module is connected to both the receiver's IF module and the transmitter's IF module; the transmitter's RF module is connected to both the transmitter's IF module and the calibration loop, and the calibration loop is connected to both the receiver's RF front-end module and the transmitter's IF module. Compared with existing technologies, the transceiver system of this invention offers the following advantages: Through the calibration loop, closed-loop calibration between the receiver and transmitter is achieved, eliminating DC bias mismatch, amplitude mismatch, and phase mismatch between the receiver and transmitter, optimizing local oscillator leakage and sideband suppression, thereby significantly improving the performance of the transceiver system.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and more particularly to a transceiver system. Background Technology

[0002] With the development of wireless communication technology and the widespread application of frequencies, high-precision RF transceiver systems have become the mainstream. Consequently, the requirements for transceiver systems are becoming increasingly stringent. In particular, it is difficult for transmitters in transceiver systems to achieve high linearity under high output power conditions. During signal transmission, factors such as manufacturing processes and device packaging can lead to signal asymmetry in the I and Q paths, as well as PN mismatches. These mismatches are ultimately amplified infinitely by the power amplifier, thus affecting the overall performance of the transmitter.

[0003] Therefore, in order to solve the problems of amplitude asymmetry, phase asymmetry, and DC bias asymmetry in the IQ channels of the transceiver system, there is an urgent need for a transceiver system with closed-loop calibration function. Upon power-up, the system performs initial loop calibration to eliminate mismatches generated in the channels, eliminate carrier leakage and sideband suppression, thereby improving the performance of the transmitter in the transceiver system. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a transceiver system that, by performing closed-loop calibration between the receiver and transmitter, eliminates the mismatch between the receiver and transmitter, optimizes the local oscillator leakage of the receiver and transmitter, and suppresses sidebands, thereby greatly improving the performance of the transceiver system.

[0005] To solve the above-mentioned technical problems, the present invention is implemented according to the following solution:

[0006] A transceiver system is provided, including: a receiver, a transmitter, a digital calibration module, and a calibration loop;

[0007] The receiver's RF front-end module is connected to the receiver's analog intermediate frequency (IF) module; the digital calibration module is connected to the receiver's IF module and the transmitter's IF module; the transmitter's RF module is connected to the transmitter's IF module and the calibration loop; the calibration loop is connected to the receiver's RF front-end module and the transmitter's IF module.

[0008] Compared with the prior art, the beneficial effects of the transceiver system of the present invention are as follows: by using a calibration loop, closed-loop calibration between the receiver and the transmitter is achieved, thereby eliminating DC bias mismatch, amplitude mismatch, and phase mismatch generated between the receiver and the transmitter, optimizing the local oscillator leakage and sideband suppression of the receiver and the transmitter, and thus greatly improving the performance of the transceiver system.

[0009] Optionally, the calibration loop includes: an auxiliary frequency converter module, a down-frequency converter module, a switching module, and a frequency divider;

[0010] The auxiliary frequency conversion module is connected to the transmitter's radio frequency module, the transmitter's analog intermediate frequency module, and the down-conversion module; the down-conversion module is connected to the switch module and the frequency divider; the switch module is connected to the receiver's radio frequency front-end module.

[0011] Optionally, the auxiliary frequency converter module includes an I-channel auxiliary frequency converter circuit, a Q-channel auxiliary frequency converter circuit, a first resistor, and a second resistor;

[0012] The P terminal of the I-channel auxiliary frequency converter circuit and the P terminal of the Q-channel auxiliary frequency converter circuit are connected to a first resistor; the N terminal of the I-channel auxiliary frequency converter circuit and the N terminal of the Q-channel auxiliary frequency converter circuit are connected to a second resistor; the first resistor and the second resistor are connected to the power supply voltage; the downconverter module is connected to the I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit.

[0013] The I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit have the same structure; the I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit each include an auxiliary transconductance amplifier unit and an auxiliary mixer; the transmitter's analog intermediate frequency module is connected to the first resistor and the second resistor in sequence through the auxiliary transconductance amplifier unit and the auxiliary mixer.

[0014] Optionally, the auxiliary transconductance amplification unit includes a third transconductance catheter and a fourth transconductance catheter;

[0015] The auxiliary mixer is connected to the drain of the third crossconductor and the drain of the fourth crossconductor; the analog intermediate frequency module of the transmitter is connected to the gate of the third crossconductor and the gate of the fourth crossconductor; the source of the third crossconductor and the source of the fourth crossconductor are both grounded.

[0016] Optionally, the switch module includes: a first switch, a second switch, a third switch, a fourth switch, a fifth switch, and a sixth switch;

[0017] The first switch is connected to the downconversion module, the second switch, and the sixth switch; the third switch is connected to the downconversion module, the fourth switch, and the fifth switch; the fifth switch and the sixth switch share a common ground; the receiver's RF front-end module is connected to the second switch and the fourth switch.

[0018] Optionally, the receiver's radio frequency front-end module includes a low-noise amplifier, a secondary frequency converter, and a transimpedance amplifier; the receiver's analog intermediate frequency module includes a filter and an analog-to-digital converter.

[0019] The low-noise amplifier is connected to the digital calibration module in sequence through the secondary frequency converter, the transimpedance amplifier, the filter, and the analog-to-digital converter; the calibration loop is connected to the secondary frequency converter.

[0020] Optionally, the analog intermediate frequency module of the transmitter includes a digital-to-analog converter, a filter, and a transconductance amplifier, and the radio frequency module of the transmitter includes a main frequency conversion unit and a balun unit;

[0021] The digital calibration module is connected to the balun unit in sequence through the digital-to-analog converter, the filter, the transconductance amplifier, and the main frequency conversion unit; the transconductance amplifier is connected to the switching module through the auxiliary frequency conversion module and the down-frequency conversion module.

[0022] The main frequency conversion unit, the auxiliary frequency conversion module, and the down-conversion module achieve frequency conversion using a common local oscillator. The local oscillator frequencies of the main frequency conversion unit and the auxiliary frequency conversion module are simultaneously generated by the voltage-controlled oscillator of the transmitter. The local oscillator frequency of the down-conversion module in the calibration loop is directly generated by the voltage-controlled oscillator of the transmitter through the frequency divider.

[0023] Optionally, the main frequency converter unit includes an I-channel main frequency converter circuit, a Q-channel main frequency converter circuit, and a capacitor array;

[0024] The capacitor array is connected to the I-channel main frequency converter circuit, the Q-channel main frequency converter circuit, and the balun unit; the analog intermediate frequency module of the transmitter is connected to the I-channel main frequency converter circuit and the Q-channel main frequency converter circuit.

[0025] The I-channel main frequency converter circuit and the Q-channel main frequency converter circuit have the same structure; the I-channel main frequency converter circuit and the Q-channel main frequency converter circuit respectively include a main transconductance amplifier unit and a main mixer.

[0026] Optionally, the main transconductor amplification unit includes a first transconductor and a second transconductor;

[0027] The main mixer is connected to the drain of the first crossconductor and the drain of the second crossconductor; the analog intermediate frequency module of the transmitter is connected to the gate of the first crossconductor and the gate of the second crossconductor; the source of the first crossconductor and the source of the second crossconductor are both grounded.

[0028] A closed-loop calibration method is also provided, applied to the aforementioned transceiver system, comprising:

[0029] The baseband signal is converted from digital to analog and filtered by a digital-to-analog converter and a filter to obtain an intermediate frequency voltage signal. The intermediate frequency voltage signal is then converted into an intermediate frequency current signal by a transconductance amplifier. The baseband signal is the signal received by the transmitter.

[0030] When calibration is enabled, the intermediate frequency current signal is sequentially up-converted by the auxiliary frequency conversion module and down-converted by the down-conversion module to obtain a radio frequency signal within the same frequency range as the input signal; the input signal is the signal received by the receiver.

[0031] The radio frequency signal is input to the radio frequency front-end module of the receiver via the switching module, and undergoes secondary down-conversion to convert the radio frequency signal to an intermediate frequency signal. The intermediate frequency signal is then processed by the analog intermediate frequency module of the receiver to obtain a digital signal. The digital signal is then processed by the digital calibration module to obtain a calibration bias. The calibration bias is fed back to the transmitter to achieve closed-loop calibration between the receiver and the transmitter.

[0032] When calibration is complete, calibration is turned off. The intermediate frequency current signal is converted into a high frequency signal by the main frequency converter unit, and the high frequency signal is converted from differential to single-ended output by the balun unit. Attached Figure Description

[0033] Figure 1 The overall frame of the transceiver system of the present invention Figure 1 ;

[0034] Figure 2 The overall frame of the transceiver system of the present invention Figure 2 ;

[0035] Figure 3 This is a block diagram of the calibration loop of the transceiver system of the present invention;

[0036] Figure 4 This is a schematic diagram of the local oscillator of the calibration loop of the present invention.

[0037] Explanation of reference numerals in the attached figures: 1. Receiver; 101. Receiver's RF front-end module; 102. Receiver's analog intermediate frequency module; 2. Transmitter; 201. Transmitter's RF module; 2011. Main frequency conversion unit; 20111. Main transconductance amplifier unit; 20112. Main mixer; 2012. Balun unit; 202. Transmitter's analog intermediate frequency module; 3. Digital calibration module; 4. Calibration loop; 401. Auxiliary frequency conversion module; 4011. Auxiliary transconductance amplifier unit; 4012. Auxiliary mixer; 402. Down-conversion module; 403. Switching module; 404. Frequency divider. Detailed Implementation

[0038] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims. In the description of this application, it should be understood that the terms "first," "second," "third," etc., are used only to distinguish similar objects and are not necessarily used to describe a specific order or sequence, nor should they be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0040] See Figure 1 As shown, the transceiver system provided by the present invention includes: a receiver 1, a transmitter 2, a digital calibration module 3, and a calibration loop 4; the radio frequency front-end module 101 of the receiver is connected to the analog intermediate frequency module 102 of the receiver; the digital calibration module 3 is connected to the analog intermediate frequency module 102 of the receiver and the analog intermediate frequency module 202 of the transmitter; the calibration loop 4 is connected to the radio frequency front-end module 101 of the receiver, the radio frequency module 201 of the transmitter, and the analog intermediate frequency module 202 of the transmitter.

[0041] The receiver's RF front-end module 101 receives the input signal, down-converts and amplifies it, and then transmits it to the receiver's analog intermediate frequency module 102. The receiver's analog intermediate frequency module 102 filters and performs analog-to-digital conversion on the signal transmitted by the receiver's RF front-end module 101 to obtain a digital signal. The digital calibration module 3 calibrates the digital signal output by the receiver's analog intermediate frequency module 102 to obtain a digital calibration signal. The transmitter's analog intermediate frequency module 202 processes the digital calibration signal output by the digital calibration module 3 to obtain an intermediate frequency analog signal.

[0042] When calibration is off, calibration loop 4 is inactive, and the intermediate frequency (IF) analog signal is converted into a high-frequency signal by the transmitter's RF front-end module 201 and transmitted. When calibration is on, the IF analog signal is sequentially up-converted and down-converted by calibration loop 4 to obtain an RF signal with the same frequency range as the input signal. This RF signal is then down-converted again by the receiver's RF front-end module 101 to convert it into an IF voltage signal. The receiver's analog IF module 102 filters and converts the IF voltage signal into a digital signal, which is then calibrated by the digital calibration module 3 to obtain a calibration bias that is fed back to the transmitter 2. This sequentially achieves closed-loop calibration between receiver 1 and transmitter 2, eliminating DC bias mismatch, amplitude mismatch, and phase mismatch between receiver 1 and transmitter 2, optimizing local oscillator leakage and sideband suppression in receiver 1 and transmitter 2, thereby greatly improving the performance of the transceiver system through calibration loop 4.

[0043] The calibration loop 4 includes: an auxiliary frequency conversion module 401, a down-conversion module 402, a switching module 403, and a frequency divider 404; the auxiliary frequency conversion module 401 is connected to the transmitter's RF module 201, the transmitter's analog intermediate frequency module 202, and the down-conversion module 402; the down-conversion module 402 is connected to the switching module 403 and the frequency divider 404; the switching module 403 is connected to the receiver's RF front-end module 101.

[0044] The auxiliary frequency converter module 401 includes an I-channel auxiliary frequency converter circuit, a Q-channel auxiliary frequency converter circuit, a first resistor R1, and a second resistor R2. The P-terminal of the I-channel auxiliary frequency converter circuit and the P-terminal of the Q-channel auxiliary frequency converter circuit are connected to the first resistor R1. The N-terminal of the I-channel auxiliary frequency converter circuit and the N-terminal of the Q-channel auxiliary frequency converter circuit are connected to the second resistor R2. The first resistor R1 and the second resistor R2 are connected to the power supply voltage AVDD, which is used to provide power. The downconversion module 402 receives signals from the I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit.

[0045] Since the difference between the two signals is only in their phase, the processing circuits for the two signals have the same structure. In one embodiment of the present invention, the I-channel auxiliary frequency conversion circuit and the Q-channel auxiliary frequency conversion circuit have the same structure. The I-channel auxiliary frequency conversion circuit and the Q-channel auxiliary frequency conversion circuit each include an auxiliary transconductance amplifier unit 4011 and an auxiliary mixer 4012. The transmitter's analog intermediate frequency module 202 is connected to the first resistor R1 and the second resistor R2 in sequence through the auxiliary transconductance amplifier unit 4011 and the auxiliary mixer 4012.

[0046] The auxiliary transconductance amplifier unit 4011 includes a third transconductor M3 and a fourth transconductor M4; the auxiliary mixer 4012 is connected to the drain of the third transconductor M3 and the drain of the fourth transconductor M4; the analog intermediate frequency module 202 of the transmitter is connected to the gate of the third transconductor M3 and the gate of the fourth transconductor M4; the source of the third transconductor M3 and the source of the fourth transconductor M4 are both grounded.

[0047] The switch module 403 includes: a first switch SW1, a second switch SW2, a third switch SW3, a fourth switch SW4, a fifth switch SW5, and a sixth switch SW6; the first switch SW1 is connected to the downconversion module 402, the second switch SW2, and the sixth switch SW6; the third switch SW3 is connected to the downconversion module 402, the fourth switch SW4, and the fifth switch SW5; the fifth switch SW5 and the sixth switch SW6 share a common ground; the receiver's RF front-end module 101 is connected to the second switch SW2 and the fourth switch SW4.

[0048] The receiver's RF front-end module 101 includes a low-noise amplifier, a secondary converter, and a transimpedance amplifier; the receiver's analog intermediate frequency module 102 includes a filter and an analog-to-digital converter (ADC); the low-noise amplifier is connected to the digital calibration module 3 in sequence through the secondary converter, the transimpedance amplifier, the filter, and the ADC; the calibration loop 4 is connected to the secondary converter.

[0049] The transmitter's analog intermediate frequency module 202 includes a digital-to-analog converter (DAC), a filter, and a transconductance amplifier. The transmitter's radio frequency module 201 includes a main frequency conversion unit 2011 and a balun unit. The digital calibration module 3 is connected to the balun unit 2012 in sequence via the DAC, filter, transconductance amplifier, and main frequency conversion unit 2011. The transconductance amplifier is connected to the switching module 403 via the auxiliary frequency conversion module 401 and the down-conversion module 402.

[0050] The main frequency converter unit 2011 includes an I-channel main frequency converter circuit, a Q-channel main frequency converter circuit, and a capacitor array C; the capacitor array C is connected to the I-channel main frequency converter circuit, the Q-channel main frequency converter circuit, and the balun unit 2012; the transmitter's analog intermediate frequency module 202 is connected to the I-channel and Q-channel main frequency converter circuits.

[0051] Since the difference between the I and Q signals is only in their phase, the processing circuits for the two signals have the same structure. In one embodiment of the present invention, the I-channel main frequency converter circuit and the Q-channel main frequency converter circuit have the same structure. The I-channel main frequency converter circuit and the Q-channel main frequency converter circuit each include a main transconductance amplifier unit 20111 and a main mixer 20112. The transmitter's analog intermediate frequency module 202 is connected to the capacitor array C and the balun unit 2012 in sequence through the main transconductance amplifier unit 20111 and the main mixer 20112.

[0052] The main transconductor amplification unit 20111 includes a first transconductor M1 and a second transconductor M2; the main mixer 20112 is connected to the drain of the first transconductor M1 and the drain of the second transconductor M2; the analog intermediate frequency module 202 of the transmitter is connected to the gate of the first transconductor M1 and the gate of the second transconductor M2; the source of the first transconductor M1 and the source of the second transconductor M2 are both grounded.

[0053] In one embodiment of the present invention, the digital baseband signal is converted from a digital signal to an analog signal by a digital-to-analog converter (DAC), and the analog signal is filtered by a filter and then converted and amplified by a transconductance amplifier to obtain an intermediate frequency signal.

[0054] When calibration is enabled, the main frequency converter 2011 is turned off, and the calibration loop 4 is up-converted by the auxiliary frequency converter 401. The auxiliary frequency converter 401 amplifies the current through the third transducer M3 and the fourth transducer M4. The current signal is up-converted into a high-frequency signal by the auxiliary mixer 4012. Since the main frequency converter 2011 needs to achieve high output power, it usually uses a high voltage domain of 1.8V, while the voltage of the receiver's RF front-end module 101 uses a low voltage domain of 0.9V. Therefore, the auxiliary frequency converter 4012 adopts a resistive load form, and provides common mode to the high-frequency signal through the first resistor R1 and the second resistor R2 respectively, realizing the cross-voltage domain conversion (1.8V to 0.9V).

[0055] Because receiver 1 and transmitter 2 operate at different frequencies, i.e., the receiving channel of receiver 1 and the transmitting channel of transmitter 2 operate at different frequencies, the intermediate frequency analog signal will undergo a down-conversion after being up-converted by auxiliary frequency conversion module 401. This converts the transmitter's transmitting frequency to the receiver's receiving frequency range. In other words, the intermediate frequency analog signal is converted into a radio frequency signal with the same frequency range as the input signal received by receiver 1 after being up-converted and down-converted in sequence. The local oscillator signal of down-conversion module 402 is generated by dividing the LO of channel 404tx by 1 / n, where the value of n can be continuously adjusted between 2 and 512. The radio frequency signal (current signal) after down-conversion enters the input terminal of secondary mixer through switch module 403, and undergoes a second down-conversion with the local oscillator signal (input signal) received by receiver 1 to convert it into an intermediate frequency signal. Finally, it is converted into a voltage signal by transimpedance amplifier.

[0056] After being filtered by a filter, the voltage signal is converted into a digital signal by an analog-to-digital converter (ADC) and input to the digital calibration module 3. The digital calibration module 3 calibrates the digital signal and obtains a digital calibration signal, which is then fed back to the input of the transmitter.

[0057] When calibration loop 4 is working (calibration loop 4 is on), the first switch SW1, the second switch SW2, the third switch SW3, and the fourth switch SW4 are in the on state, and the fifth switch SW5 and the sixth switch SW6 are in the off state. The radio frequency signal is transmitted to the radio frequency front-end module 101 of the receiver through the switch module 403.

[0058] When calibration loop 4 is not working (calibration loop 4 is closed), the first switch SW1, the second switch SW2, the third switch SW3, and the fourth switch SW4 are in the off state, and the fifth switch SW5 and the sixth switch SW6 are in the on state.

[0059] When the signals from receiver 1 and transmitter 2 experience partial leakage through the first switch SW1, the second switch SW2, the third switch SW3, and the fourth switch SW4, respectively, the leaked signals will be grounded through the fifth switch SW5 and the sixth switch SW6, thereby reducing crosstalk between receiver 1 and transmitter 2. In addition, the linearity of calibration loop 4 is limited by the power supply voltage. The receiver's RF front-end module 101 uses a low voltage domain (0.9V). The higher the power, the more severe the linearity deterioration. Therefore, the auxiliary frequency conversion module 401 uses low gain amplification to achieve low power output, generally around 0dBm. The main frequency conversion unit 2011 uses a high voltage domain (1.8V) and can achieve a linear output of 5dBm.

[0060] See Figure 4 As shown, a schematic diagram of the local oscillator of calibration loop 4 is presented. The main frequency conversion unit 201 and the auxiliary frequency conversion module 401 adopt a common local oscillator to realize frequency conversion. The local oscillator frequencies of the main frequency conversion unit 201 and the auxiliary frequency conversion module 401 are simultaneously generated by the voltage-controlled oscillator TX_VCO of the transmitter, which generates the local oscillator frequency FLO. The down-conversion module 402 in calibration loop 4 realizes the frequency difference conversion between receiver 1 and transmitter 2. Its local oscillator frequency is directly generated by the voltage-controlled oscillator TX_VCO of the transmitter through the 1 / n divider 404. Its frequency is FLO / n, and the value of n can be continuously adjusted between 2 and 512. It does not require the additional voltage-controlled oscillator TX_VCO of the transmitter, which greatly simplifies the complexity of calibration loop 4 and improves the practicality of calibration loop 4.

[0061] After calibration is completed, calibration loop 4 is closed, the main frequency converter unit 201 operates normally, and the first switch SW1, the second switch SW2, the third switch SW3, and the fourth switch SW4 change from the on state to the off state, while the fifth switch SW5 and the sixth switch SW6 change from the off state to the on state. Through the auxiliary frequency converter module 401, the impact on the main frequency converter unit 201 can be reduced during closed-loop calibration in calibration loop 4, without increasing additional power consumption, thus improving the reliability of transmitter 2 in the transceiver system. It can also realize closed-loop calibration between receiver 1 and transmitter 2, eliminating DC bias mismatch, amplitude mismatch, and phase mismatch in the transceiver system, thereby improving the overall performance of the transceiver.

[0062] This invention provides a closed-loop calibration method applied to the aforementioned transceiver system. The closed-loop calibration method includes:

[0063] First, the baseband signal (the signal received by transmitter 2) is converted from digital to analog by a digital-to-analog converter (DAC) and filtered to obtain an intermediate frequency voltage signal. The intermediate frequency voltage signal is then converted into an intermediate frequency current signal by a transconductance amplifier.

[0064] When calibration is enabled (calibration loop 4 is enabled), the intermediate frequency current signal is sequentially up-converted by the auxiliary frequency conversion module 401 and down-converted by the down-conversion module 402 to obtain a radio frequency signal in the same frequency range as the input signal (the signal received by receiver 1). The radio frequency signal is input to the receiver's radio frequency front-end module 101 via the switch module 403, that is, input to the secondary frequency converter for secondary down-conversion to convert the radio frequency signal to an intermediate frequency signal. The intermediate frequency signal is processed by the receiver's analog intermediate frequency module 102 to obtain a digital signal. The digital signal is processed by the digital calibration module 3 to obtain a calibration bias. The calibration bias is fed back to the input of transmitter 2 to realize closed-loop calibration between receiver 1 and transmitter 2.

[0065] When calibration is complete, calibration is turned off (calibration loop 4 is turned off). The intermediate frequency current signal output by the transmitter's analog intermediate frequency module 202 is converted into a high-frequency single-ended signal by the transmitter's radio frequency module 201 and finally transmitted. Specifically, the intermediate frequency current signal is converted into a high-frequency signal by the main frequency conversion unit 2011, and the high-frequency signal is then converted from differential to single-ended output by the balun unit 2012, i.e., a high-frequency single-ended signal.

[0066] The following is combined Figure 2-3 The detailed process of calibrating the transceiver system using a closed-loop calibration method is explained in detail below:

[0067] The baseband signal (the signal received by transmitter 2) is converted into an intermediate frequency (IF) current signal after digital-to-analog conversion and filtering by a digital-to-analog converter (DAC), a filter, and a transconductance amplifier (analog IF module 202 of the transmitter). When calibration loop 4 is working (calibration loop 4 is enabled), the IF current signal is sequentially amplified and mixed by auxiliary transconductance amplifier unit 4011 and auxiliary mixer 4012 (auxiliary frequency conversion module 401) to obtain a high-frequency signal. The first resistor R1 and the second resistor R2 provide bias for the auxiliary frequency conversion module 401 to achieve a certain gain. Then, the high-frequency signal is down-converted by the down-conversion module 402 to adjust the frequency of the signal to match the frequency of the input signal RX_IN received by receiver 1. Radio frequency (RF) signals of the same range are input to the receiver's RF front-end module 101 (secondary frequency converter) via switch module 403 for secondary down-conversion to convert the RF signal into an intermediate frequency (IF) signal. The IF signal is then processed by the receiver's analog IF module 102 to obtain a digital voltage signal. The digital voltage signal is then processed by the digital calibration module 3 using a calibration algorithm to obtain a calibration bias. This calibration bias includes adjustments to the mismatch error generated in the transmitter's analog IF module 202 (e.g., a transconductance amplifier) ​​and calibration loop 4. Furthermore, by feeding the calibration bias back to the input of transmitter 2 to eliminate the mismatch, closed-loop calibration is achieved between receiver 1 and transmitter 2, improving the overall performance of the transceiver system.

[0068] When calibration is complete (calibration loop 4 is closed), the intermediate frequency current signal is amplified and mixed by the main transconductance amplifier unit 20111, the main mixer unit 20112, and the capacitor array C (main frequency converter unit 2011) to obtain a differential output high-frequency signal. The high-frequency signal is finally converted into a single-ended output signal TX_OUT by the balun unit 2012 and transmitted. At the same time, the dual balanced terminals of the balun unit 2012 provide a load for the main frequency converter unit 2011 to achieve high-gain amplification.

[0069] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A transceiver system, characterized in that, include: Receiver, transmitter, digital calibration module and calibration loop; The radio frequency front-end module of the receiver is connected to the analog intermediate frequency module of the receiver; The digital calibration module is connected to the analog intermediate frequency module of the receiver and the analog intermediate frequency module of the transmitter; the radio frequency module of the transmitter is connected to the analog intermediate frequency module of the transmitter and the calibration loop. The calibration loop is connected to the radio frequency front-end module of the receiver and the analog intermediate frequency module of the transmitter; The calibration loop includes: an auxiliary frequency conversion module, a down-conversion module, a switching module, and a frequency divider; when calibration is enabled, the auxiliary frequency conversion module up-converts the output signal of the transmitter's analog intermediate frequency module. The auxiliary frequency conversion module is connected to the transmitter's radio frequency module, the transmitter's analog intermediate frequency module, and the down-conversion module; the down-conversion module is connected to the switching module and the frequency divider; the switching module is connected to the receiver's radio frequency front-end module. The baseband signal is sequentially converted from digital to analog, filtered, and amplified by the transmitter's analog intermediate frequency module to obtain an intermediate frequency current signal; the baseband signal is the signal received by the transmitter. When calibration is enabled, the intermediate frequency current signal is sequentially up-converted and down-converted through the calibration loop to obtain a radio frequency signal within the same frequency range as the input signal; the input signal is the signal received by the receiver. The radio frequency signal is down-converted twice by the radio frequency front-end module of the receiver to convert the radio frequency signal to an intermediate frequency signal. The intermediate frequency signal is then passed through the analog intermediate frequency module of the receiver to obtain a digital signal. The digital signal is then calibrated by the digital calibration module to obtain a calibration bias. The calibration bias is fed back to the transmitter to achieve closed-loop calibration between the receiver and the transmitter. When calibration is complete, calibration is turned off. The intermediate frequency current signal is converted into a high frequency signal by the transmitter's radio frequency module, and then the high frequency signal is differentially converted into a single-ended output.

2. The transceiver system according to claim 1, characterized in that, The auxiliary frequency converter module includes an I-channel auxiliary frequency converter circuit, a Q-channel auxiliary frequency converter circuit, a first resistor, and a second resistor; The P terminal of the I-channel auxiliary frequency converter circuit is connected to the P terminal of the Q-channel auxiliary frequency converter circuit via a first resistor. The N terminal of the I-channel auxiliary frequency converter circuit is connected to the N terminal of the Q-channel auxiliary frequency converter circuit via a second resistor. The first resistor and the second resistor are connected to the power supply voltage; The downconversion module is connected to the I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit; The I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit have the same structure; The I-channel auxiliary frequency converter circuit and the Q-channel auxiliary frequency converter circuit each include an auxiliary transconductance amplifier unit and an auxiliary mixer. The transmitter's analog intermediate frequency module is connected to the first resistor and the second resistor in sequence through the auxiliary transconductance amplifier unit and the auxiliary mixer.

3. The transceiver system according to claim 2, characterized in that, The auxiliary transconductance amplification unit includes a third transconductance conduit and a fourth transconductance conduit; The auxiliary mixer is connected to the drain of the third crossconductor and the drain of the fourth crossconductor; the analog intermediate frequency module of the transmitter is connected to the gate of the third crossconductor and the gate of the fourth crossconductor; the source of the third crossconductor and the source of the fourth crossconductor are both grounded.

4. The transceiver system according to claim 3, characterized in that, The switch module includes: a first switch, a second switch, a third switch, a fourth switch, a fifth switch, and a sixth switch; The first switch is connected to the downconversion module, the second switch, and the sixth switch; the third switch is connected to the downconversion module, the fourth switch, and the fifth switch; the fifth switch and the sixth switch share a common ground; the receiver's RF front-end module is connected to the second switch and the fourth switch.

5. A transceiver system according to claim 4, characterized in that, The receiver's radio frequency front-end module includes a low-noise amplifier, a secondary frequency converter, and a transimpedance amplifier; the receiver's analog intermediate frequency module includes a filter and an analog-to-digital converter. The low-noise amplifier is connected to the digital calibration module in sequence through the secondary frequency converter, the transimpedance amplifier, the filter, and the analog-to-digital converter; the calibration loop is connected to the secondary frequency converter.

6. A transceiver system according to claim 5, characterized in that, The transmitter's analog intermediate frequency module includes a digital-to-analog converter, a filter, and a transconductance amplifier; the transmitter's radio frequency module includes a main frequency conversion unit and a balun unit; when calibration is off, the main frequency conversion unit up-converts the output signal of the transmitter's analog intermediate frequency module into a high-frequency signal. The digital calibration module is connected to the balun unit in sequence through the digital-to-analog converter, the filter, the transconductance amplifier, and the main frequency conversion unit; the transconductance amplifier is connected to the switching module through the auxiliary frequency conversion module and the down-frequency conversion module. The main frequency conversion unit, the auxiliary frequency conversion module, and the down-conversion module achieve frequency conversion using a common local oscillator. The local oscillator frequencies of the main frequency conversion unit and the auxiliary frequency conversion module are simultaneously generated by the voltage-controlled oscillator of the transmitter. The local oscillator frequency of the down-conversion module in the calibration loop is directly generated by the voltage-controlled oscillator of the transmitter through the frequency divider.

7. A transceiver system according to claim 6, characterized in that, The main frequency conversion unit includes an I-channel main frequency conversion circuit, a Q-channel main frequency conversion circuit, and a capacitor array; The capacitor array is connected to the I-channel main frequency converter circuit, the Q-channel main frequency converter circuit, and the balun unit. The transmitter's analog intermediate frequency module is connected to the I-channel main frequency converter circuit and the Q-channel main frequency converter circuit; The I-channel main frequency converter circuit and the Q-channel main frequency converter circuit have the same structure; The I-channel main frequency converter circuit and the Q-channel main frequency converter circuit each include a main transconductance amplifier unit and a main mixer.

8. A transceiver system according to claim 7, characterized in that, The main transconductor amplification unit includes a first transconductor and a second transconductor; The main mixer is connected to the drain of the first crossconductor and the drain of the second crossconductor; the analog intermediate frequency module of the transmitter is connected to the gate of the first crossconductor and the gate of the second crossconductor; the source of the first crossconductor and the source of the second crossconductor are both grounded.

Images