不对称二元调制信号的增强

项目名称： 不对称二元调制信号的增强

项目编号： No.60872075

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 吴乐南

作者单位： 东南大学

项目金额： 30万元

中文摘要： 不对称二元偏移键控(ABSK)调制可大幅提高实际频谱利用率，特殊的接收滤波器可显著增强其能量利用率，研究价值很高。本项目： 1、揭示了ABSK接收机中用于提升解调前信噪比的特殊滤波机理，发明并实现了独特的数字冲击滤波器和性能优异的晶体冲击滤波器，导出了对给定冲击滤波器分别采用抽样判决与积分判决的BER表达式，拓展了经典的匹配滤波和相关检测理论，完善了高效通信的理论基础。 2、构思了更为合理的冲击滤波加几何特征判决的ABSK解调器架构，从而不仅在AWGN信道，而且在衰落信道和带宽受限信道，都得到了超过积分判决的解调性能。 3、针对ABSK中最为简单的反相调制和缺周期调制波形，并利用冲击滤波器的独特性质，实现了可省去DAC和ADC的ABSK-MODEM。 4、在2.4GHz载频直接进行缺周期调制和数字冲击滤波包络解调，AWGN信道无任何编码，按照-60dB功率带宽考核，数据率为2Mbps时频谱利用率超过90bps/Hz，BER=10-5时所需SNR不足7dB。 5、向高速猝发通信、短波通信、卫星通信、无线传感器网络、电力线通信、数字对讲机、塑料光纤通信、数字声音广播等应用领域进行了拓展。

中文关键词： 不对称调制；信号增强；冲击滤波器；频谱利用率；信噪比

英文摘要： The asymmetric binary shift keying (ABSK) modulated signal is capable of substantially increasing the spectral efficiency. With the assistance of the specialized receive filter, the energy efficiency can also be improved where the bandwidth of the signal is designed to be larger than that of the noise, which is expected to be beneficial for real applications. 1) The project reveals the mechanism of the specialized filter for the improvement of signal-to-noise-ratio (SNR) before the ABSK demodulation. The unique digital impulse filter and the exceptional crystal impulse filter are invented. The formulation of bit-error-rate (BER) using sampling-decision and sampling-integration-decision is explicitly given, respectively. The theory of classic matching-filtering and correlation-detection is extended so that the framework of high-efficiency communications is more comprehensive. 2) The demodulation scheme using combined impulse-filtering and geometrical-decision is presented. Simulation results in additive Gaussian white noise (AWGN) channel, Rayleigh fading channel as well as bandwidth-limited channel demonstrate that it outperforms the sampling-decision scheme. 3) Considering the unique property of the impulse filter, the ABSK modems using phase-reversal keying (PRK) and missing-cycle modulation (MCM) are implemented where the DAC and ADC are omitted. 4) The spectral efficiency exceeds 90 bps/Hz for MCM and digital impulse filter based envelop demodulation in AWGN without channel coding. The data rate achieves 2M bps and SNR is less than 7dB for BER=10-5. 5) It's potentially applicable for high-speed burst communications, short-wave communications, satellite communications, wireless sensor networks (WSN), power-line communications (PLC), digital interphones, plastic fiber communications and digital audio broadcasting (DAB).

英文关键词： Asymmetric Modulations；Signal Enhancing；Impacting Filter；Spectrum Efficiency；SNR