Peak to Average Power Ratio and Bit Error Ratio Analysis of MIMO SFBC CI-OFDM System | Original Article

ABSTRACT:

In this paper we are going to discuss OFDM, CIOFDM, MIMO, SFBC. The OFDM design is fairly complex and some important design blocks are chosen for verification purposes. The CI-OFDM (carrier interferometry orthogonal frequency division multiplexing) system has been widely studied in the multi-carrier communication system. In this paper, focusing on the two Tx (transmit) / one Rx (receive) antennas and two Tx / two Rx antennas configuration, we evaluate the performance of MIMO OFDM and MIMO CIOFDM system. SFBC (space frequency block coding) is applied into both MIMO OFDM system and MIMO CIOFDM system. For CI- OFDM realization, digital implemented CIOFDM structure is used in which CI code spreading operation and carrier allocation are separately processed by simple IFFT type operation. From the simulation results, it is shown that MIMO SFBC CI-OFDM reduces PAPR significantly compared with MIMO SFBC-OFDM system. The out-of band re-growth of signal spectrum in MIMO SFBC CIOFDM system is much smaller than MIMO SFBC OFDM. In the NBI (narrow band interference) channel MIMO SFBC CIOFDM system achieves considerable BER improvement, compared with the MIMO SFBC-OFDM system in which error floor occurs in most of SNR range.