Detection method for fast code acquisition in frequency-selective fading channels

摘要

PURPOSE: A method for quickly acquiring a code in a frequency selective attenuation channel is provided to quickly the code by setting a threshold value of a detector using a code precedence statistics quantity and an approximate method and removing a time required in the estimation of a signal to noise ratio. CONSTITUTION: Normal and orthogonal measuring values are obtained. A combination probability density function of the measuring values, code vectors of the measuring values, discrete combination probability mass functions of level precedence vectors are calculated. A test statistics quantity of a local optimum detector, a test statistics quantity of a local optimum precedence detector, a test statistics quantity of a local semi-optimum precedence detector, and a test statistics quantity of the kth corrected code precedence detector are calculated. A threshold value and a statistics parameter are determined using the calculated test statistics quantity.