CN115483988A

CN115483988A - Multichannel phased array transmitter amplitude-phase calibration system and method

Info

Publication number: CN115483988A
Application number: CN202211036411.7A
Authority: CN
Inventors: 闫娜; 孙安; 许灏
Original assignee: Fudan University
Current assignee: Fudan University
Priority date: 2022-08-28
Filing date: 2022-08-28
Publication date: 2022-12-16

Abstract

The invention belongs to the technical field of wireless communication, and particularly relates to a multichannel phased array transmitter amplitude-phase calibration system and method. The system of the invention comprises: the device comprises N transmitting channels, an output dynamic matching network, a first multiplexer, a second multiplexer, a down-conversion module, an amplitude-phase detection module, a control module and a register module; the modules form a closed loop detection system; at the front end of antenna transmission, the output ends of the N transmission channels are connected to a first multiplexer and an antenna through an output dynamic matching network; the control module controls the first multiplexer to select the output signals of the multiple channels, after the output signals pass through the down-conversion module, the amplitude and the phase of the output signals are measured through the amplitude and phase detection module, and the control module completes the amplitude and phase calibration of the multiple channels by utilizing the attenuator array and the phase shifter array of the phased array transmitting channel. The system can realize on-chip integration or partial on-chip integration, and can realize automatic high-speed calibration without detection equipment such as a vector analyzer and the like.

Description

Multichannel phased array transmitter amplitude-phase calibration system and method

Technical Field

The invention belongs to the technical field of wireless communication, and particularly relates to a multichannel phased array transmitter amplitude and phase calibration system and method.

Background

In the field of wireless communications, phased array transmitters often have multiple transmit channels. To achieve the desired performance of the transmitter, a good consistency in amplitude and phase between the channels is required. However, due to non-ideal factors such as chip manufacturing process and temperature, the amplitude and phase of multiple channels are deviated, so that the amplitude and phase of the multi-channel phased array transmitter need to be calibrated.

The traditional method for calibrating the amplitude and phase among the phased array transmitting channels needs to transmit through an antenna, needs a corresponding receiving device, a vector network analyzer and the like, and has high requirements on hardware. The extra calibration equipment also needs to consume a large amount of field and time, and when the number of channels to be calibrated is large, the measurement efficiency is low.

Disclosure of Invention

The invention aims to provide a multichannel phased array transmitter amplitude-phase calibration system and method capable of saving field and time consumption.

The invention provides a multichannel phased array transmitter amplitude-phase calibration system, wherein a circuit module of the multichannel phased array transmitter amplitude-phase calibration system comprises:

n transmitting channels 100 which are multi-channel phased array transmitters to be tested; n is a natural number not less than 2;

an output dynamic matching network 110, configured to implement impedance matching between the output ends of the N transmission channels and the antenna under different applications, where the front end of the antenna is connected to a multiplexer 1 (MUX 1) 120; the module may be integrated on-chip or partially integrated on-chip;

the multiplexer 1 (MUX 1) 120 may gate the output signals of the single or multiple N transmission channels to enter the multiplexer 1 (MUX 1) 120, and enter the down-conversion module 130 after being synthesized; the module may be integrated on-chip or partially integrated on-chip;

a down-conversion module 130 for down-converting the output signal of the multiplexer 1 (MUX 1) 120 to an intermediate frequency, and entering an amplitude-phase detection module 140; the module may be integrated on-chip or partially integrated on-chip;

an amplitude and phase detection module 140 for detecting the amplitude and phase of the intermediate frequency signal; the module may be integrated on-chip or partially integrated on-chip;

the multiplexer 2 (MUX 2) 150 is used for selecting the input of a calibration signal, and can realize the automatic calibration of a closed loop in the system and also select an external signal to input the external calibration; the module may be integrated on-chip or partially integrated on-chip;

the control module 160 is used for controlling the gating of the multiplexer 1 (MUX 1) 120 and the multiplexer 2 (MUX 2) (150), receiving the amplitude and phase information of the amplitude and phase detection module 140 or the external calibration signal to realize automatic calibration, and storing the calibrated control information into the register module 170; the module may be integrated on-chip or partially integrated on-chip;

the register module 170 is configured to store control information obtained after calibrating the amplitude and the phase of the transmission channel; the module may be integrated on-chip or partially integrated on-chip; the circuit module which can be integrated on chip or partially integrated on chip is adopted to cooperate with the control module 160 to form a system which can be used for calibrating the amplitude and the phase in a closed loop manner, so that the automatic and efficient phased array multi-channel amplitude and phase calibration is realized.

The invention also provides a multichannel phased array transmitter amplitude-phase calibration method based on the system, which comprises the following specific steps:

(1) The control module 160 controls the multiplexer 1 (MUX 1) 120 to select one or more transmit channels as reference channels and one or more of the remaining channels as channels to be calibrated;

(2) The control module 160 provides a set of control information, and sets the amplitudes and phases of the reference channel and the channel to be calibrated, respectively; after the setting is completed, the output signal divides the radio frequency input signal into N paths through the power divider 101, enters N paths of transmitting channels and is modulated through the attenuator array 103 and the phase shifter array 104; after passing through the output dynamic matching network 110, the multiplexer 1 (MUX 1) 120, and the down-conversion module 130, the modulated signal transmits amplitude and phase information to the control module 160 through the amplitude and phase detection module;

(3) The control module 160 controls the multiplexer 2 (MUX 2) 150 to calculate the amplitude difference and the phase difference between the reference channel and the channel to be calibrated respectively according to the amplitude phase detection result or according to the external calibration signal input, and adjusts the attenuator array 103 and the phase shifter array 104 according to the amplitude difference and the phase difference until the calibration is completed; the control information of the channel to be tested obtained after calibration is stored in the register module 170;

(4) Selecting one or more of the other channels as the channels to be calibrated again, and repeating the steps (2) and (3) until the calibration of the amplitudes and the phases of all the channels is completed;

(5) And giving another set of control information by the control module 160, and repeating the steps (2), (3) and (4) until the calibration of the required amplitude and phase is completed.

The amplitude and phase calibration system of the multi-channel phased array transmitter provided by the invention can also select external calibration signal input through the multiplexer 2 (MUX 2) 150, thereby conveniently realizing external calibration. The system can realize on-chip integration or partial on-chip integration, and can realize automatic high-speed calibration without detection equipment such as a vector analyzer and the like.

Drawings

FIG. 1 is a block diagram of a calibration system embodying the present invention.

Fig. 2 is a block diagram of an N-way transmit channel implementation of the present invention.

Detailed Description

The invention is further described below with reference to the figures and examples.

Referring to fig. 1, a block diagram of a multi-channel phased array transmitter amplitude and phase calibration system is shown, which includes: n transmit channels (N is a natural number not less than 2) 100, an output dynamic matching network 110, a multiplexer 1 (MUX 1) (120), a multiplexer 2 (MUX 2) 150, a down-conversion module 130, an amplitude-phase detection module 140, a control module 160, and a register module 170.

Fig. 2 is a block diagram of a structure of N transmission channels 100, and a radio frequency signal enters the output dynamic matching network 110 after passing through the transmission channels. Wherein the N transmit channels 110 include: the power divider 101 divides the rf signal into N paths and sends the N paths to the driver array 102, the N paths of attenuator array 103, the N paths of phase shifter array 104, and the N paths of power amplifier array 105. Each attenuator in the attenuator array 103 is stepped by 0.5dB, the maximum attenuation is 31.5dB, the phase shift precision of each phase shifter in the phase shifter array 104 is 5.625 °, and the phase shift range is 360 °.

The control module controls the output signal of the gated emission channel of the MUX1 (120), and after passing through the down-conversion module 130 and the amplitude-phase detection module 140, the control module transmits the amplitude-phase information to the control module 160, so as to achieve amplitude-phase calibration.

The channel 1 is selected as a reference channel, and the control module gives a control signal to ensure that the attenuation is 0dB and the phase shift is 0 degrees. The control module 160 controls the MUX1 to gate the transmission channel 2 as a channel to be calibrated, obtains the amplitude difference and the phase difference between the channel to be calibrated and the reference channel as A1 and a P1, adjusts the control signal by the control module 160 so that A1 and P1 are within an acceptable error range, and stores the control information into the register module 170. And then, channels to be calibrated are changed into channels 3, 4 and 5 \8230, and the calibration process is repeated by N, so that the amplitude and phase calibration of the channels with the attenuation and phase shift of 0dB and 0 degree respectively is completed.

The control module 160 traverses the attenuation and phase shift states of the reference channel (attenuation: 0-31.5dB, phase shift: 0-360 degrees), and in the state corresponding to each attenuation and phase shift, the amplitude and phase of the channels 2, 3 and 4 \8230Nare calibrated, that is, the phase calibration of the phased array transmitting channel is completed.

Claims

1. A multichannel phased array transmitter amplitude phase calibration system, comprising:

(1) N transmitting channels (100) which are multi-channel phased array transmitters to be tested; n is a natural number not less than 2;

(2) The output dynamic matching network (110) is used for realizing the impedance matching of the output ends of the N paths of transmitting channels and the antenna under different applications, and the front end of the antenna is connected with the first multiplexer (120); the module may be integrated on-chip or partially integrated on-chip;

(3) The first multiplexer (120) is used for gating the output signals of the single or multiple N transmission channels into the first multiplexer (120), and the output signals are synthesized and then enter the down-conversion module (130); the module may be integrated on-chip or partially integrated on-chip;

(4) A down-conversion module (130) for down-converting the output signal of the first multiplexer (120) to an intermediate frequency and entering an amplitude-phase detection module (140); the module may be integrated on-chip or partially integrated on-chip;

(5) An amplitude and phase detection module (140) for detecting the amplitude and phase of the intermediate frequency signal; the module may be integrated on-chip or partially integrated on-chip;

(6) The second multiplexer (150) is used for selecting the input of the calibration signal to realize the closed-loop automatic calibration inside the system or selecting the input of an external signal to input the external calibration; the module may be integrated on-chip or partially integrated on-chip;

(7) The control module (160) is used for controlling the gating of the first multiplexer (120) and the second multiplexer (150), receiving the amplitude and phase information of the amplitude and phase detection module (140) or the external calibration signal to realize automatic calibration, and storing the calibrated control information into the register module (170); the module may be integrated on-chip or partially integrated on-chip;

(8) The register module (170) is used for storing the control information obtained after the amplitude and the phase of the transmitting channel are calibrated; the module is integrated or partially integrated on-chip; an on-chip integrated or partially-on-chip integrated circuit module is adopted to cooperate with a control module (160) to form a system capable of carrying out closed-loop amplitude-phase calibration, so that automatic and efficient phased array multi-channel amplitude-phase calibration is realized.

2. A multichannel phased array transmitter amplitude and phase calibration method based on the system of claim 1 is characterized by comprising the following specific steps:

(1) The control module (160) controls the first multiplexer (120) to select one or more transmitting channels as reference channels and one or more of the rest channels as channels to be calibrated;

(2) The control module (160) gives a group of control information, and the amplitude and the phase of the reference channel and the amplitude and the phase of the channel to be calibrated are respectively set; after the setting is finished, the output signal divides the radio frequency input signal into N paths through a power divider (101), enters N paths of transmitting channels and is modulated through an attenuator array (103) and a phase shifter array (104); after passing through an output dynamic matching network (110), a first multiplexer (120) and a down-conversion module (130), the modulation signal transmits amplitude and phase information to a control module (160) through an amplitude and phase detection module);

(3) The control module (160) controls the second multiplexer (150) to respectively calculate the amplitude difference and the phase difference of the reference channel and the channel to be calibrated according to the amplitude phase detection result or according to the input of an external calibration signal, and adjusts the attenuator array (103) and the phase shifter array (104) according to the amplitude difference and the phase difference until the calibration is completed; the control information of the channel to be tested obtained after calibration is stored in a register module (170);

(4) Selecting one or more of the other channels as channels to be calibrated again, and repeating the steps (2) and (3) until the calibration of the amplitude and the phase of all the channels is completed;

(5) And (5) giving another set of control information by the control module (160), and repeating the steps (2), (3) and (4) until the required amplitude and phase calibration is completed.