Obtaining higher data rate and better spectral efficiency is a major goal of modern communication system. Single antenna, no diversity systems suffer from limited spectral efficiency and higher bit error rate (BER). Several multi-antenna techniques have been developed to obtain higher data rate and high spectral efficiency. In this paper, the authors have studied the performance of single antenna and several spatially modulated multi-antenna systems in the presence of frequency selective channels and multi-path propagation. Spectral efficiency and bit error rate (BER) have been compared for single antenna, Alamouti, SIMO and MISO systems. The authors finally conclude that MISO system can be used to design next generation energy efficient mobile network that will provide higher data rate.