A loop-based iq imbalance adaptive blind compensation method and system

Abstract

The invention belongs to the technical field of communications, and relates to a loop-based IQ imbalance self-adaptive blind compensation method, comprising: receiving an unbalanced signal x(n) through two channels of I and Q, and intercepting a discrete signal of a certain length; Set the step factor; perform conjugate processing on the received signal x(n) to get x * (n); process the received signal x(n) to obtain the compensated output signal y(n)=x(n)+w(n)x * (n), where w(n) is the compensation coefficient; the step coefficient is introduced and the compensation coefficient w(n) is smoothed, and the compensation coefficient w(n) required by the system is obtained by loop iteration, and then the compensated The output signal y(n) of . The IQ imbalance adaptive blind compensation method of the present invention is able to operate in any quadrature receiver setup, whether single or multi-channel, and is independent of any specific structure or characteristics of the ideal baseband equivalent signal. The invention also provides a loop-based IQ imbalance adaptive blind compensation system.

Description

technical field [0001] The invention belongs to the technical field of communication, and relates to a cycle-based IQ imbalance self-adaptive blind compensation method and system. Background technique [0002] IQ imbalance refers to the amplitude and phase mismatch between in-phase (In-phase, I) and quadrature-phase (Quadrature-phase, Q) branches of a transmitter and a receiver. Ideally, the in-phase and quadrature branches have equal magnitude gain and 90-degree phase deviation. However, in an actual communication system, it is usually difficult to realize the above ideal situation, thus resulting in IQ imbalance. In the transmitter, non-ideal up-conversion, unbalanced filters and digital-to-analog converters in the I and Q branches, etc. may generate IQ imbalance. At the receiver, non-ideal down-conversion, unbalanced filters in the I and Q branches, amplification, and sampling can all cause IQ imbalance. [0003] A common way to suppress IQ imbalance is to start from t...

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Problems solved by technology

[0003] A common way to suppress IQ imbalance is to start from the hardware and use high-performance analog devices (filters, amplifiers, analog-to-digital converters, etc.), although high-performance analog devices can fundamentally suppress the impact of IQ imbalance , but high-performance analog devices are generally larger in size and higher in cost, which correspondingly increases the power consumption and price of mobile transceiver equipment

In addition, high-performance analog devices cannot completely suppress IQ imbalance, and the ability to suppress IQ imbalance in different environments (temperature, humidity, etc.) will be different, so suppressing IQ imbalance in the analog domain is not very practical

If you cannot start from the analog domain, you can only suppress and compensate the IQ imbalance in the digital domain through digital signal processing.

[0004] However, the existing IQ imbalance compensation algorithms in the digital domain are often difficult to balance high compensation performance and low computational complexity, and it is also difficult to adjust the algorithm structure for different systems

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