Investment Of Harq Technology Based On Ieee802.16e

At present, the spread of wireless channel environment subjects to various fading, noise interference, multipath effects. Doppler frequency shift and other factors, has a great impact on the quality of communication. Error control technology as an effective means to solve this problem. In digital systems, using error detection code or error correcting codes is divided in mainly of two parts: automatic repeat request ARQ and Forward Error Correction FEC. Hybrid automatic repeat request (HARQ) technology is an effective combination of FEC and ARQ technology, not only reduces unnecessary overhead of FEC, but can achieve higher throughput than relatively simple ARQ.In this thesis, the HARQ technology based on the IEEE 802.16e protocol was investigated. First, introduced the system architecture of the IEEE 802.16e protocol, and then conduct relevant principles and the specific implementation of HARQ technology based on IEEE802.16e protocol, focused on the performance of the Chase HARQ. For Chase HARQ conducted in-depth simulation and analysis. Second, by testing the HARQ buffer allocation and use of the data of the actual system, presented a data buffer dynamically allocated and real-time control strategy. Then, conducted the key technologies for the IEEE802.16e protocol:MIMO (Multiple Input and Multiple Output) and AMC (Adaptive Modulation and Coding), proposed the combination of HARQ and MIMO strategies to achieve adaptive MIMO mode. At last, proposed method of HARQ and AMC joint control, the use of HARQ technology can reduce the modulation encoding requirements of identification and measurement error and flow volatility sensitivity.