Research On Lte/Lte-a Physical Layer Receiver Algorithms

This work focuses on the receiver algorithms designs of LTE and LTE-A uplink transmission, which is the next generation wireless communication technology.LTE uplink transmission is based on Single Carrier Frequency Domain Division Multiple Access (SC-FDMA). Being a single carrier technology, SC-FDMA makes use of Single Carrier Frequency Domain Equalization (SC-FDE) on the receiver side to combat inter-symbol interference (ISI). Current research of SC-FDE is mainly about nonlinear frequency domain equalization algorithms, including frequency domain decision feedback equalization (FD-DFE) and Turbo equalization. After the introducing of Single User MIMO (SU-MIMO), the received signal will suffer from ISI as well as inter-stream interference in LTE-A uplink transmission. On this condition, the employment of Turbo equalization for detection on the receiver is expected to improve system performance compared with the relatively simple linear detection. This wok employs Turbo equalization to LTE and LTE-A uplink transmission, proposes and further evaluates receiver algorithms and the corespongding structure suitable to the algorithms.Link adaption is another technology of great importance used in LTE and LTE-A system, it includes Adaptive Modulation and Coding (AMC) and the adaption of MIMO transmission parameters. It is necessary for the designed receiver detection algorithms to be evaluated simultaneously with the link adaption algorithms. Meanwhile, to achieve the potential gain promised by the use of nonlinear detection algorithms, a link adaption algorithm suits the receiver with nonlinear detection should be proposed. This work proposes a new algorithm which is simple and useful. Meanwhile, it can work well with both linear and nonlinear detection algorithms. Finally, the turbo equalization algorithm is evaluated accompanied with the link adaption algorithm. Simulation results show that the use of Turbo equalization in LTE-A uplink transmission detection will bring considerable benefits to system throughput.