Performance Improvement for MIMO Communication Systems Employing Per Transmit Antenna Differential Encoding (PADE)

This paper proposes performance improvement schemes for multiple-input multiple-output (MIMO) communication systems employing per transmit antenna differential encoding (PADE), which generates an independent differentially encoded sequence for each of the multiple transmit antennas by means of space-time coding and mapping. PADE can operate without channel state information (CSI) at both the transmitter and the receiver. This paper proposes the following schemes suitable for PADE: 1) novel mapping schemes for transmit diversity (TD) and spatial multiplexing (SM); and 2) introduction of the state-reduction algorithm for per-survivor processing (PSP), if the channel is estimated by a large number of observation symbols of the received signal. Next, computer simulation confirms that the proposed schemes can improve bit error rate (BER) performance and can mitigate floor of BER on slowly time-varying fading channels, keeping small hardware complexity