Application of Pseudo Random Binary Sequence (PRBS) signal in system identification

Abstract

This project emphasized on both software and hardware analysis. Pseudo random binary sequence (PRBS) signal of 15 different maximum length sequences were developed using MATLAB software and were used as forcing function in simulated second order. There are four second order system responses that were examined; overdamped, underdamped, undamped and critically damped. For each response, traces of the output response of system forced by PRBS or without PRBS in the absence or presence of noise were analyzed. The autocorrelation function of the input signal and cross correlation function between input and output signal were performed using MATLAB software. From the correlograms of autocorrelation and cross correlation, the transfer function of the system was estimated. For verification of the simulation work, PRBS generator circuit was build using Transistor-transistor logic. The PRBS signal generated was analyzed using Dynamic Signal Analyzer. An experiment using PRBS as the forcing function to an unknown system was performed. The autocorrelation function of the input signal and cross correlation function between input and output signal were performed using Dynamic Signal Analyzer and the transfer function model of the unknown system was estimated. Results from this experiment were used to validate the simulation work previously.