Research and Implementation of the PHY Error Control Mechanism on Broadband Wireless Ad Hoc Network

无线自组织网是一组自治的无线节点相互协作而形成的独立于固定的基础设施并采用分布式管理的网络。由于它具有组网灵活、容易实现等优点，在军事通信、应急通信等方面有广阔的应用前景。宽带无线自组织网是一种无线通信和计算机网络相结合的网络，它的应用环境复杂，信道误码率高，数据传输速率高，实时性好，要求有较高的可靠性。因此相对于一般通信系统，有效的差错控制方案对于宽带无线自组织网而言显得更为重要。 CTC与Turbo码相比具有编码效率高，相同复杂度译码器下纠错性能好，译码迭代次数少，译码时延小等优点，同时消除了尾比特对译码性能的影响。文中通过仿真验证，得到译码迭代次数相同时，CTC的性能略优于Turbo码...Wireless Ad Hoc network is a kind of peer-to-peer network. With the advantages of network flexibility and easy realization, it has bright prospects in military communications, emergency communications, etc. Wireless Ad Hoc network incorporates wireless communications networks and computer networks. Compared with the general communication system, more effective error control scheme is required in b...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115218

可聴音を利用した近距離情報伝送技術に関する研究

筑波大学 (University of Tsukuba)201

Performance analysis of adaptive interleaving for OFDM systems

We proposed a novel interleaving technique for orthogonal frequency division multiplexing (OFDM), namely adaptive interleaving, which can break the bursty channel errors more effectively than traditional block interleaving. The technique rearranges the symbols according to instantaneous channel state information of the OFDM subcarriers so as to reduce or minimize the bit error rate (BER) of each OFDM frame. It is well suited to OFDM systems because the channel state information (CSI) values of the whole frame could be estimated at once when transmitted symbols are framed in the frequency dimension. Extensive simulations show that the proposed scheme can greatly improve the performance of the coded modulation systems utilizing block interleaving. Furthermore, we show that the adaptive interleaving out performs any other static interleaving schemes, even in the fast fading channel (with independent fading between symbols). We derived a semi-analytical bound for the BER of the adaptive interleaving scheme under correlated Rayleigh fading channels. Furthermore, we discussed the transmitter-receiver (interleaving pattern) synchronization problem.published_or_final_versio