针对无人自主车同时定位与地图构建(Simultaneous Localization And Mapping,SLAM)问题,采用随机有限集(Random Finite Set,RFS)方法对环境特征和车辆的位姿进行描述,将SLAM算法涉及到的多路标特征检测、跟踪、识别及相关等问题在一个...针对无人自主车同时定位与地图构建(Simultaneous Localization And Mapping,SLAM)问题,采用随机有限集(Random Finite Set,RFS)方法对环境特征和车辆的位姿进行描述,将SLAM算法涉及到的多路标特征检测、跟踪、识别及相关等问题在一个统一的贝叶斯状态估计框架内表述,从而可以有效地解决后验估计、信息融合等算法严重依赖数据关联结果的问题。同时,为了计算复杂的联合后验分布,解决粒子滤波算法中提议分布选择困难问题,采用序贯蒙特卡罗(Sequential Monte Carlo,SMC)算法为马尔科夫链蒙特卡罗(Markov Chain Monte Carlo,MCMC)采样构建高维提议分布策略,提出了基于PMCMC-RFS(Particle MCMC based RFS)的SLAM问题求解方法。试验结果表明:PMCMC-RFS算法能动态估计感知范围内的特征数量,有效地避免了数据关联问题,从而提高了状态估计性能。展开更多
As a promising candidate for millimeter wave(mmWave)multiple-input and multiple-output(MIMO)communications,hybrid precoding techniques can reap the benefit of large antenna arrays,yet with only limited number of radio...As a promising candidate for millimeter wave(mmWave)multiple-input and multiple-output(MIMO)communications,hybrid precoding techniques can reap the benefit of large antenna arrays,yet with only limited number of radio frequency(RF)chains.In this paper,we investigate the problem of achieving the same performance of the fully digital system with hybrid precoding.Specifically,for the single user MIMO system,we propose a closed form hybrid precoding design that can achieve the optimal fully digital performance for both frequency-flat and frequency-selective channels,and only requires the number of RF chains to equal the number of paths of the channel.The design for the case with even less RF chains is also given.Furthermore,for the multiuser(MU)system with single antenna at each mobile terminal(MT),twoMU beamforming schemes are considered,which are the directional beamforming and zero-forcing.We show that for both schemes,the fully digital performance can be achieved with our proposed hybrid precoding designs with the number of RF chains no less than the sum number of channel paths from the base station to all the selected MTs.Numerical results are provided to validate our analytical results and show the performance gain of the proposed hybrid precoding designs compared to other benchmark schemes.展开更多
文摘针对无人自主车同时定位与地图构建(Simultaneous Localization And Mapping,SLAM)问题,采用随机有限集(Random Finite Set,RFS)方法对环境特征和车辆的位姿进行描述,将SLAM算法涉及到的多路标特征检测、跟踪、识别及相关等问题在一个统一的贝叶斯状态估计框架内表述,从而可以有效地解决后验估计、信息融合等算法严重依赖数据关联结果的问题。同时,为了计算复杂的联合后验分布,解决粒子滤波算法中提议分布选择困难问题,采用序贯蒙特卡罗(Sequential Monte Carlo,SMC)算法为马尔科夫链蒙特卡罗(Markov Chain Monte Carlo,MCMC)采样构建高维提议分布策略,提出了基于PMCMC-RFS(Particle MCMC based RFS)的SLAM问题求解方法。试验结果表明:PMCMC-RFS算法能动态估计感知范围内的特征数量,有效地避免了数据关联问题,从而提高了状态估计性能。
文摘As a promising candidate for millimeter wave(mmWave)multiple-input and multiple-output(MIMO)communications,hybrid precoding techniques can reap the benefit of large antenna arrays,yet with only limited number of radio frequency(RF)chains.In this paper,we investigate the problem of achieving the same performance of the fully digital system with hybrid precoding.Specifically,for the single user MIMO system,we propose a closed form hybrid precoding design that can achieve the optimal fully digital performance for both frequency-flat and frequency-selective channels,and only requires the number of RF chains to equal the number of paths of the channel.The design for the case with even less RF chains is also given.Furthermore,for the multiuser(MU)system with single antenna at each mobile terminal(MT),twoMU beamforming schemes are considered,which are the directional beamforming and zero-forcing.We show that for both schemes,the fully digital performance can be achieved with our proposed hybrid precoding designs with the number of RF chains no less than the sum number of channel paths from the base station to all the selected MTs.Numerical results are provided to validate our analytical results and show the performance gain of the proposed hybrid precoding designs compared to other benchmark schemes.
