A Comparison of Various Channel Estimation Techniques to Improve Fading Effects in MIMO over Different Fading Channels

In wireless communication systems MIMO systems are implemented to reduce the effects of multipath fading. Various fadings like Rayleigh fading, racian fading occurs in atmosphere. These fadings effect the performance of communication channel and to reduce fading various techniques are developed, one of them is diversity technique. Various diversity techniques are used to remove effects of fading. Channel estimation is carried out to know the effects of fading on system channel. Channel estimation in any system is done using various methods like BER, Mean square error analyses, etc. This paper is concerned with channel estimation of MIMO communication systems using techniques STBC and SFBC under various fading channels. STFBC, a latest technique is based on a chain of events for space time and space frequency codes. In this technique, STBC and SFBC are used for pilot and data subcarriers, forming the different combinations of SFBC/STBC and STBC/SFBC. Finally SFBC, STBC and STFBC techniques are analysed and compared. Effect on channel estimation is shown in form of graphs.