Matlab Simulation for the DiPPM with RS system - Essay Example

The Matlab software was used to simulate the DiPPM system (Appendix-?). The system design was depended on the DiPPM system troth table, table ( ). The DiPPM system program contains two main sections, DiPPM coder and DiPPM decoder. The first step is a clock and a random binary PCM signal generating. The generated PCM signal is changing every running of the simulation to produce a different binary PCM signal. Thus, different DiPPM pulses are being shaped. The second step is calling the DiPPM coder subroutine.

The DiPPM coder subroutine was used to create the DiPPM signal (SET & RESET) from the binary PCM signal. Each change from zero to one in PCM sequence gives SET in DiPPM signal, and the change from one to zero in PCM sequence produces an RESET pulse in DiPPM. No pulse generated in DiPPM signal when the PCM sequence does not change. The third step in this program was used to regenerate the original PCM sequence from the DiPPM sequence (DiPPM decoder). The program is going to produce a binary one in PCM sequence when it receives an SET pulse, and it continues until an RESET pulse is received to produce a binary zero.

The fourth step of the program is applied to change the binary sequence (one & zero) to pulse shape. Plots output for the DiPPM coder and decoder system were set in the last part of the program. Figure (5.1), shows the DiPPM system results for two different PRBS PCM sequences. Each run simulation produces four line output plot, clock sequence in the first line, then the PCM sequence and DiPPM and Decoded PCM sequence are coming respectively. It is clear from the figure that the system working as the DiPPM theory mentioned, chapter three.

The first function is for RS encoder and the second function for RS decoder. The encoder function encodes the message in (msg) using an [n,k] Reed Solomon code and specifies the generator polynomial (genpoly) for the code. The message is a Galois array of symbols having m bits each.