Title :
Extended properties of high-order spectral-null words
Author :
Xin, Yan ; Fair, Ivan J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Alberta Univ., Edmonton, Alta., Canada
Abstract :
High-order spectral-null codes have found practical applications in systems with high-order partial response channels. We derive a necessary and sufficient condition on word length N of Mth-order spectral-null code words, denoted dc/sup M/ words. A new lower bound on the redundancy of dc/sup M/ words is also presented. Furthermore, we investigate truncations of the Morse sequence and prove that these truncations must represent two dc/sup M/ words with the shortest word length. We show that the power spectra of these short dc/sup M/ words (M/spl ges/2) have nulls at rational frequencies of the symbol frequency, and we derive the orders of these spectral nulls.
Keywords :
binary sequences; codes; partial response channels; spectral analysis; Morse sequence truncations; binary Morse sequence; high-order partial response channels; high-order spectral-null codes; high-order spectral-null words; lower bound; necessary condition; power spectra; rational frequencies; sufficient condition; symbol frequency; word length; word redundancy; AWGN; Additive white noise; Application software; Arithmetic; Equations; Frequency; Optical recording; Partial response channels; Polynomials; Sufficient conditions;
Conference_Titel :
Electrical and Computer Engineering, 1999 IEEE Canadian Conference on
Conference_Location :
Edmonton, Alberta, Canada
Print_ISBN :
0-7803-5579-2
DOI :
10.1109/CCECE.1999.807163
