Automatic frequency correction method and receiver for time division duplex modes of 3G wireless communications

A receiver for use in a wireless communication system, said receiver including a voltage controlled oscillator and estimating means for obtaining a frequency estimate to adjust said voltage controlled oscillator, said estimating means comprising:

• receiving means for receiving a communication signal including time slots containing data symbols and a midamble;
• correlating means for performing a given number N of block correlations of the received signal samples with a known midamble reference;
• forming means for forming a conjugate product of the N block correlations to form N−1 conjugate products;
• summing means for forming a sum of the N−1 conjugate products;
• accumulating means for accumulating a given number of sums of said N−1 conjugate products obtained from said summing means;
• determining means for determining the magnitude of each accumulated summed value;
• searching means for searching for a given number of largest summed values;
• detection means for performing a threshold detection of the given number of largest summed values other than the largest summed value, employing a threshold which is a function of the largest summed value;
• combining means for combining the largest summed value with the given number of the largest summed values other than the largest summed value and which are greater than the threshold;
• computing means for computing the magnitude of the sum obtained by said combining means;
• normalizing means for normalizing the complex value obtained by said combining means employing the magnitude obtained by said computing means;
• and
• generating means for generating an argument of the normalized value obtained by said normalizing means for a frequency estimate.