Recently, the use of coherent space-frequency coding in Orthogonal Frequency Division Multiplexing (OFDM)-based frequency-selective multiple-input multipleoutput (MIMO) antenna fading channels has been proposed [1, 2]. Acquiring knowledge of the fading coefficients in a MIMO channel is already very challenging in the flat-fading case. In the frequency-selective case, estimating the MIMO channel...

Space-time coding for fading channels is a communication technique that realizes the diversity benefits of multiple transmit antennas. Previous work in this area has focused on the narrowband flat fading case where spatial diversity only is available. In this paper, we investigate the use of space-time coding in OFDMbased broadband systems where both spatial and frequency diversity are availabl...

The use of frequency-domain interleaving on a frame-byframe basis for orthogonal frequency division multiplexing (OFDM) combined with time division multiplexing (OFDM/TDM) is presented. In conventional OFDM, FDE is not designed to exploit the channel frequencyselectivity and consequently, the frequency diversity gain cannot be obtained. To further improve the bit error rate (BER) performance of...

Abstract— This paper investigates different diversity concepts for OFDM systems. These are space frequency block codes (SFBC) and code division multiplexing (CDM). The performance of both and of combinations of both is compared for coded OFDM systems in a Rayleigh fading channel. The SFBCs and CDM applied in this paper have in common that they have no rate loss and thus do not decrease the band...

To improve performance of orthogonal frequency division multiplexing (OFDM) for fading channels, linear dispersion coded OFDM (LDC-OFDM) was recently proposed to increase frequency and time diversity with high bandwith efficiency and performance. The performance of recently proposed LDC-OFDM was investigated through simulations. This paper analyzes the diversity aspects of LDCOFDM system, and s...