Method and apparatus for I/Q imbalance calibration of a transmitter system

摘要

A method for I/Q imbalance calibration of an OFDM system comprising the steps of initializing parameters A_p, B_p and gamma_p, estimating a loop delay factor L, generating a discrete-time test signal x[n], deriving a signal x_com[n] by compensating the test signal x[n] according to a function with parameters A_p, B_p and gamma_p, converting the signal x_com[n] to an analog signal x(t), applying I/Q modulation to the signal x(t) and outputting a modulated signal x_mod(t), obtaining a characteristic signal x_c(t) of the modulated signal, obtaining a signal x_s[n] by sampling the characteristic signal x_c(t) and obtaining statistics U₁ and U₂ of the signal x_s[n], and updating the parameters A_p, B_p and gamma_p respectively by functions of L, U₁, U₂, and the current values of A_p, B_p and gamma_p.