IQ imbalance adaptive blind compensation method and system based on circulation

Abstract

The invention belongs to the technical field of communication, and relates to a cycle-based IQ imbalance adaptive blind compensation method which comprises the following steps of: receiving an I-pathsignal x (n) and a Q-path signal x (n) which have been imbalanced, and intercepting a discrete signal with a certain length; setting a stepping coefficient; performing conjugate processing on the received signal x (n) to obtain x * (n); processing the received signal x (n) to obtain a compensated output signal y (n) = x (n) + w (n) x * (n), wherein w (n) is a compensation coefficient; introducinga stepping coefficient and smoothing the compensation coefficient w (n), obtaining the compensation coefficient w (n) required by the system in a loop iteration mode, and further obtaining a compensated output signal y (n). The IQ imbalance adaptive blind compensation method of the present invention can be operated in any quadrature receiver settings, regardless of a single channel or multiple channels, and irrespective of any specific structure or characteristics of an ideal baseband equivalent signal. The invention further provides an IQ imbalance self-adaptive blind compensation system based on circulation.

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...

AI Technical Summary

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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