机构地区: 哈尔滨工业大学
出 处: 《通信学报》 2008年第7期7-13,共7页
摘 要: 针对IR-UWB(impulse radio-ultra wideband)测距定位系统中目前已有的几种非相干TOA(time of arrival)估计算法的不足,提出了一种基于能量采样序列的最大最小值比(MMR,maximum to minimum energy sample ratio)进行归一化门限设置的TC(threshold comparison)算法。通过仿真考察了最优归一化门限与MMR之间的关系,建立了以MMR为参量的最优归一化门限计算模型。该模型独立于信道模式,具有极好的通用性;同时还考虑了能量积分周期的影响,使得模型无须任何更动即可应用到不同的能量积分周期取值情况下,极大地增强了模型的灵活性。与已有的几种非相干TOA估计算法的性能对比表明,基于MMR进行门限设置的MMR-TC算法在所有信噪比范围内均能取得最优性能,验证了算法的有效性。 Aim at the performance drawbacks of those existent TOA estimation algorithms of IR-UWB systems, a TC (threshold-crossing) algorithm was proposed whose normalized threshold was set based on the MMR (maximum to minimum energy sample ratio) of the energy samples. The relationship between the optimal normalized threshold and MMR was investigated through simulations, from which the mathematical model of MMR based optimal normalized threshold calculation was built. The model is well independent of channel models, which make it widely applicable. Moreover, effects of the length of energy-integration-interval were considered, which enables the model being functional without any modifications when different energy-integration-interval lengths are used. Simulation results show that the proposed MMR-TC algorithm outperforms those existent algorithms at nearly all SNR ranges.