ARRANGEMENT FOR DETERMINING A CHARACTERISTIC FORM OF AN INPUT SIGNAL

摘要

A receiver and method for determin ing a characteristic from an input signal is disclosed. A characteristic is at least one selected from a group comprising preamble detect, frequency offset and timing offset. The input signal comprises an IF frequency fIF and a preamble signal which is a sequence of M similar data symbols. The data symbols have a symbol period SP, and M is an integer greater than or equal to 2. The method comprises: - receiving N subsequent samples of the input signal, the N subsequent s amples representing a part of the input signal approximating the symbol period SP, - rotating N subsequent samples to obtain N rotated symbols; - correlating the N rotated symbols with P correlation functions to generate a set of N x P correlation values, P being an integer greater than or equal to 2; and, - selecting a maximum correlation value from the set of N x P correlation values and determining the characteristic. The invention enables to perform an efficient antenna diversi ty circuit, which can be u sed for simultaneously timing offset and frequency offset estimation, and preamble detection for both antennae with only one radio unit.