Enchancement of GSC Using OFDM and QAM Over Reiyleign Fading Channel: A Review

As indispensable as communication has been to human endeavors, geographical and physical distance would have been a barrier to its effective deployment if not for the advent of wireless mobile communication. In the world today, most of the developments we see in all spheres of our modern life are influenced by communication technologies. However, the performance of each modulation scheme deployed in the communication system dictates the Quality of Service (QoS), effective cost management, efficient power, available bandwidth, Bit Error Rate (BER), and Signal to Noise Ratio (SNR). Extensive research has been done with different authors proffering wide ranging solutions for generalized selection combining (GSC) algorithms in the presence of noise and interfering signals. Some of the reported approaches include varying modulation schemes, changing the channel, and using different equalizing techniques. Many of these proposed solutions worked effectively in some areas while they understandably left other areas untouched, others show better performance by analyzing the channel using; Log-likelihood Ratio (LLR), integral expression, and multiple-mode transmission scheme which in turns proof to be of better performance with a good result. Despite all the efforts, overcoming the issue of noise interference in the communication channel has still been somewhat elusive. Conclusively, to reduce noise to the barest minimum in mobile/cellular communication, this review proposes modulation scheme synchronization with combined diversity technique over an improved channel that is less prone to noise.