Signals and Telecommunication Journal Patteti Krishna, Tipparti Anil Kumar, Kalitkar Kishan Rao 4 2 2015 http://www.dline.info/stj/fulltext/v4n2/v4n2_2.pdf This paper evaluates the performance of Long Term Evolution (LTE) downlink with multiple inputs and multiple outputs (MIMO) techniques, where the use of multiple antennas at the transmitter and receivers. There are different combinations of array configuration and polarization, transmission and detection schemes that can be implemented to achieve different purposes in functional and performance terms. MIMO transmissions schemes include transmit diversity and spatial multiplexing and MIMO detection schemes such as zero forcing and soft spheres decoding (SSD). The performance metrics considered are throughput and bit error rate (BER) and these are used to evaluate the performance of LTE in flat fading and International Telecommunications Union B (ITU-B) Pedestrian channel with zero forcing and soft sphere decoding for Single Input Single Output (SISO), transmit diversity and spatial multiplexing. The simulations show that the performance of MIMO is better than SISO in both channel models particularly when SSD is employed. When high order modulation is utilized, performance in the flat-fading channel model is better than ITU pedestrian B channel at low SNR regions. Spatial multiplexing is ideal for achieving very high peak rates, while transmit diversity is a valuable scheme to minimize the rate of bit error occurrence thereby improving signal quality.