Tomlinson-Harashima precoded MIMO in wireless networks: to THP or not to THP?

Official URL: http://www.springer.com/business/business+information+systems/journal/11235

We investigate a wireless network architecture that utilizes Tomlinson Harashima Precoded MIMO (THP MIMO) together with a physical layer aware scheduling technique. We address an unstudied aspect of THP MIMO by investigating the network capacity in a multi user point-to-multipoint scenario and explore the performance through extensive capacity analysis considering varying SNR levels, varying number of users and number of transmit/receive antennas, under realistic Rayleigh and Ricean fading channel models, perfect and imperfect knowledge of channel state information. We also evaluate the complexity of THP MIMO and propose a low-complexity scheduling algorithm that employs Gram-Schmidt algorithm for incremental implementation of THP’s QR factorization. Through our detailed study, we identify the network and channel conditions under which THP MIMO can be preferred over classical optimal MIMO, concluding that THP MIMO architecture is a viable alternative for practical MIMO systems due to improved capacity, low complexity and better tolerance for CSI errors.