Patent ID: 7561630

Claim:
A transmission parameter recognition apparatus, used for detecting a sample sequence and outputting a piece of guard interval information, wherein the sample sequence comprises a plurality of symbols and each of the symbols comprises a guard interval and a data interval, the transmission parameter recognition apparatus comprising: a correlation function processing module, for performing a conjugating and multiplying calculation on two adjacent symbols from the sample sequence to generate a conjugate product sequence, and accumulating these values corresponding to a sample point and MNg sample points in the conjugate product sequence to generate a value of a correlation sample point, wherein the MNg sample points are prior to the sample point, a plurality of the correlation sample points form a correlation symbol, a plurality of the correlation symbols form a correlation function sequence and MNg is a least length of the guard interval in a testing mode; a correlation symbol summing module, coupled to the correlation function processing module, for providing a first sample memory point to an (MNk+MNu)-th sample memory point, and using the sample memory points for sequentially reading and summing up the values corresponding to the correlation sample points in M correlation symbols of the plurality of the correlation symbols to generate a correlation symbol sum sequence, wherein an i-th sample memory point is adopted for reading and summing up a value of an [N*(MNk+MNu)+i]-th correlation sample point, MNu is a length of the data interval in the testing mode, MNk is equal to MNg plus a predetermined value, M is an integer, 0≦N≦M and 1≦i≦(MNk+MNu); and an energy interval detection module, coupled to the correlation symbol summing module, for detecting an energy interval of the correlation symbol sum sequence and generating the guard interval information according to the energy interval, wherein the guard interval information comprises a ratio of the guard interval length to the data interval length.