correlation peak 200 and the latest significant correlation peak 201 is the significant delay spread in the channel response this delay spread can be used to determine the minimum cyclic prefix that would maintain the orthogonality of the ofdm symbol and eliminate isi the time distance between peaks is determined by further processing of the output of the correlation corr_out from equation 1 an example of the processing steps are described below step 1 the peak value of corr_out is determined this is found using the following pseudo code and recorded as max_peak the time where the max_peak occurs is recorded as peak_time step 2 look for the first instance of a peak that exceeds a threshold x db below the peak and record this time as start_profile x assumes an initial value determined by system analysis for a particular system and is a function of the echo amplitude expected in the channel step 3 look for the last instance of a peak that exceeds a threshold x db below the peak and record this time as end_profile step 4 calculate cp_len end_profile start_profile step 5 if cp_len is greater than cyc_prefix_max reduce x by 1 db and repeat step 2 5 until cp_len is smaller than cyc_prefix_max cyc_prefix_max is the maximum cyclic prefix allowed in the data path and equals to 64 in the current embodiment step 6 reduce x by 1 db and repeat step 2 3 and 4 if the cp_len is.