Modified Space-Time Coding for Wireless Communications

The numbers of technical challenges are faced by the high-performance wireless networks because of its new optimal designs. These include regulatory limits on usable radio frequency spectrum and a complex time-varying propagation environment affected by fading and multipath. For the purpose of meeting the growing demands for higher data rates with good quality of service (QOS) with very less drop connections, the efficient techniques with the improvement in both spectral efficiency and link reliability are called for. This can be attained by usage of multiple channels in receiver and transmitting end. This helps in increasing the signal to noise ratio (SNR). In this paper, Space-Time coding (STC) is employed in MIMO signaling scheme which helps in providing better knowledge at the receiver and no knowledge at the transmitter. STC codes used in this paper are Space-time trellis codes, Linear space-time block codes and Space-Time Differential Coding. The performance of the STC code is improved by the new Space-time trellis codes proposed in this paper. When the frame error probability is evaluated, the proposed system shows lesser error probability when compared to the previous STC codes.