该文在步进频信号的基础上,把基于混沌调制的多载波相位编码(Multi-Carrier Phase Coded,MCPC)信号作为子脉冲,用Costas跳频代替频率的线性步进,设计出脉间Costas跳频脉内多载波混沌相位编码(Inter-Pulse Costas frequency hopping and ...该文在步进频信号的基础上,把基于混沌调制的多载波相位编码(Multi-Carrier Phase Coded,MCPC)信号作为子脉冲,用Costas跳频代替频率的线性步进,设计出脉间Costas跳频脉内多载波混沌相位编码(Inter-Pulse Costas frequency hopping and intra-pulse Multi-Carrier Chaotic Phase Coded,IPC-MCCPC)雷达信号,并对其模糊函数及自相关性能进行了研究。仿真分析表明,该文设计的信号继承了步进频信号用较小的瞬时带宽合成较大的工作带宽的优点,同时有效克服了步进频信号存在的距离-速度耦合的缺点。脉内多载波特性使得这种信号在保持总带宽和步进频信号相等的条件下减少跳频阶数,从而提高信号处理的数据率;混沌调相的引入使得这种信号具有更强的保密性;脉间频率的随机跳变使其模糊函数具有更低的周期性旁瓣。这种信号众多的参数、灵活的结构及较大的调制复杂度,增加了侦察接收机匹配和识别的难度,从而提高雷达的反截获性能。展开更多
射频识别技术(radio frequency identification,RFID)在室内定位领域得到广泛的关注及应用。距离估计是实现RFID室内定位的重要基础。将基于多频相位差和中国余数定理的融合方法应用于声表面波(surface acoustic wave,SAW)RFID技术,实...射频识别技术(radio frequency identification,RFID)在室内定位领域得到广泛的关注及应用。距离估计是实现RFID室内定位的重要基础。将基于多频相位差和中国余数定理的融合方法应用于声表面波(surface acoustic wave,SAW)RFID技术,实现了标签的无模糊距离估计。分析了该方法在SAWRFID系统中实现距离估计所面临的主要误差来源及相应的修正方法。通过仿真实验,得到该方法在理论上要实现高稳定性及高精度的距离估计,则SAWRFID阅读器系统的模糊相位测量误差应不超过3°的系统指标要求。最后,通过实验验证了该方法在SAWRFID系统中的可实现性,结果表明所研制的系统当前能达到的距离估计均方根误差为16.7cm。展开更多
This paper presents an enhanced multi-baseline phase unwrapping algorithm by combining an unscented Kalman filter with an enhanced joint phase gradient estimator based on the amended matrix pencil model, and an optima...This paper presents an enhanced multi-baseline phase unwrapping algorithm by combining an unscented Kalman filter with an enhanced joint phase gradient estimator based on the amended matrix pencil model, and an optimal path-following strategy based on phase quality estimate function. The enhanced joint phase gradient estimator can accurately and effectively extract the phase gradient information of wrapped pixels from noisy interferograms, which greatly increases the performances of the proposed method. The optimal path-following strategy ensures that the proposed algorithm simultaneously performs noise suppression and phase unwrapping along the pixels with high-reliance to the pixels with low-reliance. Accordingly, the proposed algorithm can be predicted to obtain better results, with respect to some other algorithms, as will be demonstrated by the results obtained from synthetic data.展开更多
文摘射频识别技术(radio frequency identification,RFID)在室内定位领域得到广泛的关注及应用。距离估计是实现RFID室内定位的重要基础。将基于多频相位差和中国余数定理的融合方法应用于声表面波(surface acoustic wave,SAW)RFID技术,实现了标签的无模糊距离估计。分析了该方法在SAWRFID系统中实现距离估计所面临的主要误差来源及相应的修正方法。通过仿真实验,得到该方法在理论上要实现高稳定性及高精度的距离估计,则SAWRFID阅读器系统的模糊相位测量误差应不超过3°的系统指标要求。最后,通过实验验证了该方法在SAWRFID系统中的可实现性,结果表明所研制的系统当前能达到的距离估计均方根误差为16.7cm。
基金supported by the National Natural Science Foundation of China(4120147961261033+2 种基金61461011)the Guangxi Natural Science Foundation(2014GXNSFBA118273)the Dean Project of Guangxi Key Laboratory of Wireless Broadband Communication and Signal Processing(GXKL061503)
文摘This paper presents an enhanced multi-baseline phase unwrapping algorithm by combining an unscented Kalman filter with an enhanced joint phase gradient estimator based on the amended matrix pencil model, and an optimal path-following strategy based on phase quality estimate function. The enhanced joint phase gradient estimator can accurately and effectively extract the phase gradient information of wrapped pixels from noisy interferograms, which greatly increases the performances of the proposed method. The optimal path-following strategy ensures that the proposed algorithm simultaneously performs noise suppression and phase unwrapping along the pixels with high-reliance to the pixels with low-reliance. Accordingly, the proposed algorithm can be predicted to obtain better results, with respect to some other algorithms, as will be demonstrated by the results obtained from synthetic data.