结合混合OFDM技术的LED室内定位算法  

LED based indoor positioning algorithm combined with hybrid OFDM

作　　者：王瑾[1] 黎好栩 张晓锋[1] 吴让仲[1] 

机构地区：[1]中国地质大学机械与电子信息学院,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2017年第11期17-21,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：教育部高等学校博士学科点专项科研基金资助项目(20120145120011)

摘　　要：现有的许多LED室内定位系统,其定位精度都受限于室内环境中的多径干扰.鉴于OFDM可在抵抗多径干扰的同时提高传输速率,提出了一种结合混合OFDM的LED室内定位算法,利用非对称限幅光OFDM调制奇载波,脉冲幅度调制-离散多音频调制技术调制偶载波的虚部,并使用接收信号强度技术确定接收机的坐标.计算了一个房间中每个点的定位误差,分析了不同系统参数对定位精度的影响,并与仅结合非对称限幅光OFDM的定位系统进行比较分析.仿真结果表明:本算法在存在多径干扰的情形下仍可实现误差低于0.2m的高精度定位,并优于仅结合非对称限幅光OFDM的室内定位算法.Since the performance of existing indoor positioning system is limited by multipath distortion,an light-emitting-diode（LED）based indoor positioning algorithm combined with hybrid orthogonal frequency division multiplexing（HOFDM）was proposed,where orthogonal frequency division multiplexing（OFDM）was applied to combat the effect of multipath distortion as well as increasing data rate.In this scheme,asymmetrically clipped optical OFDM（ACO-OFDM）was transmitted on the odd subcarriers while using pulse amplitude modulated discrete multitone（PAM-DMT）to modulate the imaginary part of each even subcarrier.Moreover,a received-signal-strength（RSS）technique was used to determine the location of the receiver.The positioning errors for all the locations in the room and the impact of different system parameters on the positioning accuracy were further investigated compared with the systems based on ACO-OFDM.Simulation results demonstrate that the proposed algorithm can achieve position error of less than 0.2 meven with multipath distortion,which outperforms its conventional counterpart.

关 键 词：非对称限幅光正交频分复用 脉冲幅度调制-离散多音频调制 多径干扰 室内定位 可见光通信 

分 类 号：TN966[电子电信—信号与信息处理] TN364[电子电信—信息与通信工程]