Patent Number:
7,822,137
Title:
System and method for symbol rate estimation using vector velocity
Abstract:
A system and method for symbol rate estimation using vector velocity that does not require any prior knowledge of the signal's structure and is accurate in the presence of frequency offset and noise. An input signal is converted to a symbol constellation path signal, and a velocity signal representing a velocity of the symbol constellation path signal is generated. A first frequency spectrum of the velocity signal is generated by performing a Fast Fourier transform on the velocity signal, and a maximum peak value of the first frequency spectrum, a first bin below the maximum peak value, and a second bin above the maximum peak value are identified. A Chirp-Z transform is performed on the velocity signal using the first bin and the second bin as coefficients, wherein performing the Chirp-Z transform generates a second frequency spectrum including only frequencies within the range of the first bin and the second bin, and wherein the second frequency spectrum presents a higher resolution than the first frequency spectrum. A maximum peak value of the second frequency spectrum is identified, wherein the maximum peak value of the second frequency spectrum corresponds to the symbol rate of the input signal.
Inventors:
Judd; Darrell Ray (Rockwall, TX), Talbert; Joshua Douglas (Garland, TX), Moses; Bruce Oliver (Rowlett, TX)
Assignee:
L3 Communications Integrated Systems, L.P.
International Classification:
H04L 27/28 (20060101)
Expiration Date:
2018-10-26 0:00:00