A receiver and method for determining 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 samples 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×P correlation values, P being an integer greater than or equal to 2; and, —selecting a maximum correlation value from the set of N×P correlation values and determining the characteristic. The invention enables to perform an efficient antenna diversity circuit, which can be used for simultaneously timing offset and frequency offset estimation, and preamble detection for both antennae with only one radio unit.