摘要 |
The present invention offers a method and apparatus for measuring the waveform quality of a CDMA signal with increased accuracy. A baseband digital measuring signal Z(k) from a quadrature transform/complementary filter 22 is applied to a demodulating part 25, wherein it is demodulated by a PN code of a pilot signal to detect a bit train and an amplitude a'i. An ideal signal Ri is generated from the bit train, the amplitude a'i and the PN code. At the same time, auxiliary data A, B, C, H and I, which are used to solve approximate simultaneous equations for computing parameters that minimize the square of the difference between the ideal signal Ri and the measuring signal Z(k), are generated in an ideal signal/auxiliary data generating part 26. The thus obtained auxiliary data and the measuring signal Z(k) are used to solve the simultaneous equations to estimate the parameters in a parameter estimating part 27. The parameters are optimized by repeatedly correcting the measuring signal Z(k), the ideal signal Ri and the auxiliary data A, B, C, H, I based on the estimated parameters and estimating the parameters based on the corrected data. When the parameters are optimized, the power coefficient rho i is computed using the optimized measuring signal Z(k) and the PN code. <IMAGE> |