Turbo Receiver B3g Systems

Beyond the third generation (B3G) mobile-communication system is expected to support a wide range of services that will require high transmission data rate and high system capacity within the limited frequency bandwidth. To achieve this goal, multiple input multiple output (MIMO)-orthogonal frequency division multiplex (OFDM) system architecture in B3G system is proposed. However, there will be system performance loss due to the difficulity of MIMO detection. In order to decrease the influence of the interference and achieve perfect system performance, Turbo receiver, which comes from the principle of turbo decoder, is undoutedly highlighted in the study of B3G system for the reason that it can improve system performance a lot by iteratively exchanging the extrinsic soft information between detector and decoder. This thesis mainly focuses on the design of Turbo receiver for B3G system, meanwhile provides methods to decrease the complexity of Turbo receiver. According to simulation results, system performance can be improved more than 4dB with iterative exchange of extrinsic soft information between soft interference cancellation (SIC) detector and low density parity check code (LDPC) decoder. OFDM is one of basic technologies in the design of B3G system. However, it has high peak to average power ratio (PAPR). To resolve the problem, clipping-noise-iterative-estimation-and-cancellation scheme is applied in Turbo receiver due to its better performance and the similar iterative structure as Turbo receiver. Furthermore, this thesis also introduces the interface structure of C language test platform of B3G system in the State "863"FuTURE Project. The author has accomplished many program and debug works in this project, especially about the framework of systems which transmission speeds are 100 Mbit / s and 50 Mbit /s.