# Enhancing BER Performance Limit of BCH and RS Codes Using Multipath Diversity +
## 8 Conclusions  
This paper shows that the performance of FEC codes can be improved in order to enhance BER performance. Furthermore, it demonstrates that a FEC with low redundancy and low error correction capability can perform better than ones with higher redundancy and higher error correction capability. This is achieved through utilising an existing phenomenon in wireless communication called multipath propagation and proposing a new combiner known as CWMC with low complexity. Additionally, the improvement in the performance of FEC increased by increasing the number of combined paths. The CWMC combiner improved BER performance, and it can be enhanced by increasing the number of the combining paths, as shown in the simulation results. Additionally, the improvement of BER performance depends on the error correction capability of the FEC codes. Furthermore, the BER performance can be improved by increasing the error correction capability (\(t\)). In other words, increasing the redundancy will improve the BER performance, while it will reduce the gross transmission rate. It is shown in the simulations that the BCH and RS codes with \(n=15\), \(k=7\), and \(t=2\), and \(n=15\), \(k=11\), and \(t=2\), respectively, improved the performance of BER more than when \(n=15\), \(k=11\), and \(t=1\), and \(n=15\), \(k=13\), and \(t=1\), respectively. In contrast, the results show that BCH and RS codes with \(t=1\) can be improved to enhance BER performance more than BCH and RS codes with \(t=2\) by using CWMC, and the transmission rate is increased. Moreover, the simulation shows that the CWMC improved BCH performance more than RS over the AWGN channel. However, the CWMC improved RS performance more than BCH over the Rayleigh channel, because the RS codes are correcting burst errors. In possible future work, this research could be extended by analysing and evaluating the performance of FEC techniques with high modulation schemes, multiple-input multiple-output (MIMO) systems, and over different wireless channel models. As open research topics, it is recommended to further investigate the following:  
* The performance of FEC codes which utilise the multipath phenomenon can be compared with turbo code performance. * The performance of LDPC code can be compared with the performance of FEC codes which employ the multipath phenomenon. * The performance analysis can be extended to codewords with different lengths. * Analyse the overall system and compare it with turbo and LDPC codes in term of complexity and overhead. Figure 13: BER vs. SNR of the RS (255,253) code with and without CWMC vs. the RS (255,251) code without CWMC, where 3P represents the three paths that were combined to improve the error correction capability of the RS (255,253) code. (**a**) The AWGN channel; and (**b**) the Rayleigh channel. **Acknowledgments:** We thank the Iraq Higher Committee for Education Development (HCED) for their financial support. We are indebted to the Faculty of Arts, Science and Technology, University of Northampton, for providing the postgraduate studentship and the software, resources, and support required. **Author Contributions:** The authors equally contributed to the reported research and writing of the paper. All authors have read and approved the final manuscript. **Conflicts of Interest:** The authors declare no conflict of interest. **Abbreviations**  
The following abbreviations are used in this manuscript: