PERFORMANCE OF NON-BINARY PROJECTION CODES
Projection Codes were introduced in 1987 in [1] by D. Schilling and D. Manela. Projection codes are a class of codes which can be implemented as FEC or ARQ codes. D. Manela in [4] showed three different classes of Projection Codes, the SM, the PSM codes and the TSM codes. The three classes of codes are similar and differed from one another in the degree of protection offered by each to the parity symbol used. It was shown then that the SM is the most basic and the simplest to implement but offered the offered the least amount of protection. G. Lomp [5] presented some theoretical approximations for the codes, particularly for the TSM code. He also showed that the theoretical analysis of the code is very complicated and hence, presented some simulation results for the performance of the code.
To understand the behavior of these codes more work was needed particularly for the non-binary case. Understanding the difficulty of the theoretical analysis of these codes we decided to study the behavior of these codes, with special emphasis of the non-binary codes, by using computer simulations. We simulated the encoding and decoding algorithms using FORTRAN for many codes from each class, the SM, the PSM, and the TSM as block codes. Using these simulation results we showed how each code reacts to variations in its parameters. We also showed how the codes compare with each other and showed that the code performs within bounds that were developed by colleague Y. Gang [21] on the performance of the codes.
E. Kanterakis [6] developed a new decoding algorithm for the convolutional TASM binary code. We extended the algorithm for the non-binary case and simulated many TASM codes using this algorithm. Again we showed the effect of variations in all the parameters on the performance of the code. We also compared the non-binary TASM block codes and the convolutional codes, and also showed that the code performs within bounds. Furthermore, we developed a hardware implementation design for the decoder of the 8-ary TASM rate ½ convolutional code with 3-data lines which can easily be altered to get a decoder for a different code.