smitted from two or more transmit antennas, a beamforming effect is created where in some directions the signal is attenuated while in other directions it may be amplified. The CDD scheme mitigates this problem by transmitting cyclically shifted signals from the transmit antennas. Let's consider an OFDM symbol with constellation dk at the kth frequency index, the time-domain signal corresponding to this symbol which is transmitted from antenna port 1 can be expressed as follows: (NFFT-1)/2 1(t) = Re ejwct 2nk(t-tg)/T (10-35) -(NFFT-1)/2 10.4 Multi-antenna transmission schemes Using CDD scheme, the transmitted signal from the second antenna port is given by (NFFT-1)/2 diei2mk(1-1g-Tcoo)/Tu (10-36) k=-(NFFT-1)/2 This is equivalent to a cyclic rotation of the signal in the time-domain. The implementation of the CDD scheme is simplified, if the cyclic shift TCDD is an integer multiple of the sampling time. At the receiver, the effect of CDD at the kth index is of receiving through the channel H1(k) + exp(j2ukTCDD/)H(k). The advantage over the case of H1(k) + H2(k), which is the result of transmission of the same signal over the two channels, is the prevention of the beamforming effect, i.e., directed transmission in one direction and undesired emission in the other directions. The main objective of spatial multiplexing, as opposed to space-time diversity coding, is to maximize transmission data rate. Therefore, min(N, independent data symbols are transmitted per symbol period, such that the spatial rate is min(N,). There are several encoding options that can be used in conjunction with spatial multiplexing to achieve the increased data rate. Horizontal Encoding (HE) and Vertical Encoding (VE) are the prominent encoding options that are typically used in wireless communication systems. In an HE scheme, the bit stream to be transmitted is de-multiplexed into separate data streams where each stream is processed through the transmission chain, i.e., independent temporal encoding, symbol mapping, and interleaving, and is 