CN111342850B

CN111342850B - Receiving array broadband quadrature imbalance compensation device

Info

Publication number: CN111342850B
Application number: CN202010133046.6A
Authority: CN
Inventors: 王璇; 宋庆辉
Original assignee: CETC 54 Research Institute
Current assignee: CETC 54 Research Institute
Priority date: 2020-03-01
Filing date: 2020-03-01
Publication date: 2021-07-06
Anticipated expiration: 2040-03-01
Also published as: CN111342850A

Abstract

The invention discloses a receiving array broadband quadrature imbalance compensation device, and belongs to the technical field of communication, radar and electronic countermeasure. The invention carries out random orthogonal phase shift on each receiving branch, constructs the broadband orthogonal unbalance of radio frequency and baseband into negative correlation, thereby enabling the broadband unbalance to be mutually offset in the process of de-orthogonal array synthesis, and then adaptively updates the calibration coefficient of the narrow-band compensation module through the narrowband unbalance estimation and calibration matrix construction, thereby realizing the narrow-band compensation. The invention can be suitable for broadband receiving arrays with any scale, can adapt to the conditions of signals of various systems, cooperative and non-cooperative signals, different signal-to-noise ratio conditions, I/Q mismatch compensation and the like caused by temperature change, and has the characteristics of broadband work, low hardware complexity, less required computing resources and the like.

Description

Receiving array broadband quadrature imbalance compensation device

Technical Field

The invention relates to the technical field of communication, radar and electronic countermeasure, in particular to a receiving array broadband quadrature imbalance compensation device.

Background

The receiving array can simplify the complexity of a receiving link, reduce power consumption and be easy to integrate by adopting a zero intermediate frequency receiver architecture, but the application of the receiving array in practical engineering is limited by some technical problems inherent in the zero intermediate frequency receiver architecture, and the invention mainly focuses on and solves the problem of amplitude-phase mismatch of the broadband I/Q branch circuit. The amplitude-phase inconsistency of the I/Q branches will create mirror frequencies, thereby degrading the dynamic range of the receive array system. The current calibration mode mainly aims at a single-path receiver, and if the calibration mode is directly extended to a receiving array for application, the required computing resources and the hardware complexity are greatly increased, so that the cost is greatly increased. Meanwhile, most of the existing I/Q mismatch compensation technologies are applied to narrow bands, so that the performance is seriously deteriorated when a plurality of non-cooperative signals which are sparsely distributed in a broadband instantaneous bandwidth are processed.

Disclosure of Invention

In view of the above problems in the prior art, an object of the present invention is to provide a wideband quadrature imbalance compensation apparatus for a receiving array, which is applicable to a wideband receiving array of any scale, and can adapt to the conditions of I/Q mismatch compensation and the like caused by signals of multiple systems, cooperative and non-cooperative signals, different signal-to-noise ratios, and temperature changes, and has the characteristics of wideband operation, low hardware complexity, and less required computing resources.

In order to achieve the purpose, the invention adopts the technical scheme that:

a receiving array broadband quadrature imbalance compensation device comprises a random quadrature phase shift module A, a narrowband compensation module B, a de-quadrature array synthesis module C and a self-adaptive imbalance estimation module D; an external signal is connected with a first port A-1 of a random quadrature phase shift module A, a second port A-2 of the random quadrature phase shift module A is connected with a first port B-1 of a narrow-band compensation module B, a second port B-2 of the narrow-band compensation module B is connected with a first port C-1 of a de-orthogonal array synthesis module C, the second port C-2 of the de-orthogonal array synthesis module C outputs a signal after self-adaptive processing to a first port D-1 of a self-adaptive unbalance estimation module D, and a second port D-2 of the self-adaptive unbalance estimation module D is connected with a third port B-3 of the narrow-band compensation module B;

n radio frequency signals input from the outside enter a first port A-1 of a random quadrature phase shift module A, N is larger than 1, the random quadrature phase shift module A randomly realizes 0/90-degree quadrature phase shift on the signals of each radio frequency channel, N paths of digitized baseband I/Q signals are output to a first port B-1 of a narrow band compensation module B through a second port A-2, and the narrow band compensation module B calibrates the input signals through a calibration matrix obtained from an adaptive imbalance estimation module D and outputs the input signals to a first port C-1 of a de-orthogonal array synthesis module C through a second port B-2; after orthogonal processing and synthesis are carried out on the signals in the de-orthogonal array synthesis module C, the signals are externally output through a second port C-2 of the de-orthogonal array synthesis module C; meanwhile, a signal output by a second port C-2 of the quadrature array synthesis module C is fed back to a first port D-1 of the self-adaptive imbalance estimation module D, the self-adaptive imbalance estimation module D carries out I/Q mismatch estimation on the fed-back signal to construct a calibration matrix, and the calibration matrix is output to a third port B-3 of the narrowband compensation module B by the second port D-2 of the self-adaptive imbalance estimation module D.

Compared with the background technology, the invention has the following advantages:

a) the broadband works, the prior I/Q calibration method mostly aims at I/Q mismatch calibration of bandwidths of several MHz to dozens of MHz, and the invention can realize I/Q mismatch calibration of bandwidths of hundreds MHz to thousands MHz.

b) The performance is influenced by a signal-to-noise ratio less, the previous I/Q mismatch extraction precision is influenced by the signal-to-noise ratio more greatly, the I/Q mismatch is extracted and a calibration matrix is constructed after array synthesis, and the extracted I/Q mismatch information has higher precision because the array synthesis can provide signal-to-noise ratio gain.

c) The hardware and computational complexity of the invention is low.

In summary, the invention combines pilot calibration and adaptive blind calibration, combines technologies such as mixed unbalance extraction and decomposition based on pilot test, frequency-independent and frequency-dependent hierarchical amplitude-phase calibration, adaptive optimization based on minimum N-dimensional space distance and the like, can be suitable for influence brought by signals of various systems, cooperative and non-cooperative signals, different signal-to-noise ratio conditions and temperature change, and is an important improvement on the prior art and the scheme.

Drawings

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

Fig. 2 is a simulated contrast diagram of the image rejection ratio of an embodiment of the invention.

FIG. 3 is a comparison graph of a multi-signal calibration simulation of an embodiment of the present invention.

Detailed Description

The present invention is described in further detail below with reference to the attached drawing figures.

Referring to fig. 1, a receiving array wideband quadrature imbalance compensation apparatus includes a random quadrature phase shift module a, a narrowband compensation module B, a de-quadrature array synthesis module C, and an adaptive imbalance estimation module D. The signal input from the outside enters an A-1 port of a random quadrature phase shift module A, an A-2 port of the random quadrature phase shift module A is connected with a B-1 port of a narrow band compensation module B, a B-2 port of the narrow band compensation module B is connected with a C-1 port of a de-orthogonal array synthesis module C, the C-2 port of the de-orthogonal array synthesis module C outputs a signal after adaptive processing and is connected with a D-1 port of an adaptive unbalance estimation module D, and a D-2 port of the adaptive unbalance estimation module D is connected with a B-3 port of the narrow band compensation module B.

The example was simulated in MATLAB by simulation as in fig. 1, and the simulation results are shown in fig. 2 and 3.

As can be seen from FIG. 2, under the condition of 40dB signal-to-noise ratio, I/Q mismatch calibration is performed on a 16-channel array, the sampling clock frequency is 256MHz, the image frequency rejection ratio IRR before calibration is about 20dB, and the image frequency rejection ratio of 70dB is realized after calibration.

As can be seen from fig. 3, the image frequency suppression degree of the baseband frequency signal with the bandwidth of 47.5MHz and the baseband frequency signal with the bandwidth of-78 MHz and the bandwidth of 6MHz is about 20dB before calibration, and is improved to about 60dB after calibration.

The invention has the following brief working principle:

n radio frequency signals (N is more than 1) received from the outside enter an A-1 port of a random orthogonal phase shift module A, the random orthogonal phase shift A randomly realizes the orthogonal phase shift of 0 degree/90 degrees on the signal of each radio frequency channel, and the A-1 port outputs N paths of digitized baseband I/Q signals; n paths of digitized baseband I/Q signals output by the A-2 port are input into a B-1 port of a narrow-band compensation module B, and are output to a C-1 port of a de-orthogonal array synthesis module C from the B-2 port after being calibrated by a calibration matrix in the narrow-band compensation module B; after the signals are subjected to orthogonal processing and synthesis in the de-orthogonal array synthesis module C, the signals are output by a C-2 port of the de-orthogonal array synthesis module C; the signal output by the C-2 port is fed back to a D-1 port of an input self-adaptive unbalance estimation module D, I/Q mismatch estimation is carried out on the synthesized signal in the self-adaptive unbalance estimation module D, and a calibration matrix is constructed and output to a B-3 port of a narrow-band compensation module B from D-2.

The invention aims at a receiving array system based on a zero intermediate frequency architecture, and can compensate the broadband quadrature imbalance, thereby improving the hybrid quadrature decorrelation and the self-adaptive blind compensation of a dynamic range. The invention constructs the broadband quadrature imbalance of the radio frequency and the baseband into negative correlation by carrying out random quadrature phase shift on each receiving branch, thereby enabling the broadband imbalance to be mutually offset in the process of de-orthogonal array synthesis, and then adaptively updating the calibration coefficient of the narrow-band compensation module by estimating the narrowband imbalance and constructing a calibration matrix, thereby realizing the narrow-band compensation. Compared with the prior art, the invention realizes the compensation of the system-level broadband quadrature imbalance of the array receiving system based on the zero intermediate frequency architecture, can compensate the consistency and the random quadrature imbalance among channels, and is particularly suitable for being used in the broadband zero intermediate frequency receiving array system in the technical fields of communication, radar and electronic countermeasure.

In a word, the invention improves and combines the array decorrelation method and the I/Q mismatch adaptive blind compensation method, can be suitable for broadband receiving arrays with any scale, can adapt to the conditions of signals of various systems, cooperative and non-cooperative signals, I/Q mismatch compensation caused by different signal-to-noise ratio conditions and temperature changes, and the like, and has the characteristics of broadband work, low hardware complexity, less required computing resources and the like.

Claims

1. A receiving array broadband quadrature imbalance compensation device is characterized in that: the device comprises a random quadrature phase shift module (A), a narrow-band compensation module (B), a de-orthogonal array synthesis module (C) and an adaptive imbalance estimation module (D); an external signal is connected with a first port (A-1) of a random quadrature phase shift module (A), a second port (A-2) of the random quadrature phase shift module (A) is connected with a first port (B-1) of a narrow band compensation module (B), a second port (B-2) of the narrow band compensation module (B) is connected with a first port (C-1) of a de-orthogonal array synthesis module (C), the second port (C-2) of the de-orthogonal array synthesis module (C) outputs a signal after self-adaptive processing to a first port (D-1) of a self-adaptive imbalance estimation module (D), and a second port (D-2) of the self-adaptive imbalance estimation module (D) is connected with a third port (B-3) of the narrow band compensation module (B);

n radio frequency signals input from the outside enter a first port (A-1) of a random quadrature phase shift module (A), N is larger than 1, the random quadrature phase shift module (A) randomly realizes 0/90 DEG quadrature phase shift on the signals of each radio frequency channel, N paths of digitalized baseband I/Q signals are output to a first port (B-1) of a narrow band compensation module (B) through a second port (A-2) of the random quadrature phase shift module (A), the narrow band compensation module (B) calibrates the input signals through a calibration matrix obtained from an adaptive imbalance estimation module (D), and the input signals are output to a first port (C-1) of a de-orthogonal array synthesis module (C) through a second port (B-2) of the narrow band compensation module (B); after the signals are subjected to orthogonal processing and synthesis in the de-orthogonal array synthesis module (C), the signals are output to the outside through a second port (C-2) of the de-orthogonal array synthesis module (C); meanwhile, a signal output by a second port (C-2) of the de-orthogonal array synthesis module (C) is fed back to a first port (D-1) of the adaptive imbalance estimation module (D), the adaptive imbalance estimation module (D) carries out I/Q mismatch estimation on the fed-back signal to construct a calibration matrix, and the calibration matrix is output to a third port (B-3) of the narrow-band compensation module (B) by the second port (D-2) of the adaptive imbalance estimation module (D).