General Method for Calculating the Spectrum of a Zero Substitution Coded Signal

Abstract

AbshacLThis paper describes a general method for calculating the power spectra of zero substitition coded signals and applies this method to calculate the B32S signal spectrum of the DS-3. Many digital radio systems transmit a signal which consists of DS-3 level baseband signals. Therefore, knowledge of the B3ZS spectral characteristics is important in DS-3 level interfeknce and systems studies.The method used for calculating spectral densities of substitution coded signals is based on signal-flow graph analysis. While signal-flow graph identities and Mason's gai. formula have been used in the past in the calculation of some substitution coded spectra, they become unduly cumbersome when applied towards ,ynplex spectra such as that of the B3ZS signal. In place of the graph identities and gain formula, two matrix techniques a& introduced that can be used in general to simplify spectral calculations for substitution coded signals.The methodology used in analyzing these communication signals can also be applied to other related fields such as coding of signals for magnetic recordings.

Performance analysis of pre-equalized multilevel partial response modulation for high-speed electrical interconnects

“…By doing so, the synchronization is improved as the maximum run length of zeros is reduced to N-1. It has been shown that this modification of bipolar line coding makes the exact computation of the PSD very tedious [20]. However, the resulting PSD is similar to the PSD of bipolar line coding.…”