A UWB/IMU-Assisted Fingerprinting Localization Framework with Low Human Efforts

With the rapid development of smart phone,the location-based services(LBS)have received great attention in the past decades.Owing to the widespread use of WiFi and Bluetooth devices,Received Signal Strength Indication(RSSI)fingerprintbased localization method has obtained much development in both academia and industries.In this work,we introduce an efficient way to reduce the labor-intensive site survey process,which uses an UWB/IMU-assisted fingerprint construction(UAFC)and localization framework based on the principle of Automatic radio map generation scheme(ARMGS)is proposed to replace the traditional manual measurement.To be specific,UWB devices are employed to estimate the coordinates when the collector is moved in a reference point(RP).An anchor self-localization method is investigated to further reduce manual measurement work in a wide and complex environment,which is also a grueling,time-consuming process that is lead to artificial errors.Moreover,the measurements of IMU are incorporated into the UWB localization algorithm and improve the label accuracy in fingerprint.In addition,the weighted k-nearest neighbor(WKNN)algorithm is applied to online localization phase.Finally,filed experiments are carried out and the results confirm the effectiveness of the proposed approach.

基于TOF和自适应抗差卡尔曼滤波的UWB室内定位算法

为提高超宽带(UWB)定位系统在室内复杂环境下的定位精度,提出一种基于飞行时间(TOF)和自适应抗差卡尔曼滤波(ARKF)的改进定位算法。针对超低功耗宽带设备在复杂室内环境状态下易受周围干扰而存在标准时间偏差的问题,提出一种改进的TOF算法,同时进行测距标定,拟合数据;对室内存在非视距(NLOS)干扰的情形,提出一种ARKF算法,通过比较残差与3倍信息的方差来判断视距(LOS)与NLOS情形。实验结果显示:该算法可以在静态与动态定位实验中有效提高系统定位精度,降低定位误差,取得较好的定位效果。

一种复杂环境下UWB测距误差预测方法

针对复杂室内环境中,多径干扰和视距遮挡影响室内定位精度的问题,提出一种复杂环境下UWB测距误差的预测方法:根据超宽带(UWB)室内定位方法抗干扰能力强、定位精度高的特点,从理论上分析影响超宽带信号测距精度的因素;然后通过模型量化分析每种影响因素对测距误差的影响程度,改进以往通过信道脉冲响应特征分析单一的视距遮挡参数来提高定位精度的补偿算法;最后从数据挖掘和机器学习的角度出发,将多径效应、视距遮挡、标签与基站的距离、标签移动速度、标签与基站天线俯仰角以及气象因素(温度、湿度、压强)等对测距精度造成影响的重要因素作为特征进行分类和归类,并使用梯度提升决策树模型对数据集进行训练和预测。实验结果表明,该模型可以根据当前状态下的组合特征值估计出测距误差值,将当前预测的误差值补偿到测量值上,可以有效提高超宽带室内定位的精度。

基于UWB的天然气站场室内三维定位系统研究

为解决天然气站场室内定位中因非视距(NLOS)现象导致人员和设备定位精度低的问题,设计了一种基于超宽带(UWB)与Three.js的天然气站场室内人员与设备三维定位系统。通过B/S三层架构,以Django框架和VUE框架为基础,利用Python、HTML5、CSS3和Three.js,实现定位信息在网页客户端的三维可视化。通过对UWB技术的研究,为保证定位精度,基于到达时间差(TDOA)测量值,采用卡尔曼滤波算法对其进行NLOS滤波,并结合Chan算法融合多基站数据,最终得到目标点的计算位置。通过搭建实验环境,对三维定位系统进行定位标签静态和动态定位实验。实验结果表明,对于NLOS现象严重的复杂室内环境,该系统定位精度高、运行平稳,能为天然气站场室内定位提供一种切实可行的技术。

A Novel UWB Signal Sampling Method for Localization based on Compressive Sensing

Ultra-wide-band (UWB) signals are suitable for localization, since their high time resolution can provide precise time of arrival (TOA) estimation. However, one major challenge in UWB signal processing is the requirement of high sampling rate which leads to complicated signal processing and expensive hardware. In this paper, we present a novel UWB signal sampling method called UWB signal sampling via temporal sparsity (USSTS). Its sampling rate is much lower than Nyquist rate. Moreover, it is implemented in one step and no extra processing unit is needed. Simulation results show that USSTS can not recover the signal precisely, but for the use in localization, the accuracy of TOA estimation is the same as that in traditional methods. Therefore, USSTS gives a novel and effective solution for the use of UWB signals in localization.

PDR与UWB融合的森林消防员定位系统设计

针对森林消防员在林区环境下由于全球导航卫星系统(GNSS)定位拒止及惯性导航误差累积而难以精确定位的问题,设计了一种融合行人航位推算(PDR)和超宽带(UWB)测距的定位系统。首先,基于消防员个体装备的便携性要求,利用加速度计、磁强计、陀螺仪和气压计设计头戴式定位系统;其次,将指挥员作为基站,利用UWB测得消防员与基站之间的距离;接着,基于扩展卡尔曼滤波(EKF)设计了PDR与UWB融合的定位算法,将测距信息与消防员的运动状态进行融合解算,约束误差发散;最后,利用设计的软硬件定位系统进行了验证实验。结果表明:在真实林区实验中,与无约束PDR相比,采用PDR与UWB融合的定位方法将位置误差减小了60.04%,有效提升了系统的定位精度。

基于时频域特征融合的IR-UWB穿墙雷达人体行为识别方法

冲激脉冲(impulse radio,IR)超宽带(ultra-wideband,UWB)穿墙雷达因其良好的穿透性和距离分辨率在穿墙人体行为识别领域具有重要作用,但是常规识别方法仅采用单域特征对行为模式进行描述,识别准确率不高。针对这一问题,提出基于时频域特征融合的IR-UWB穿墙雷达人体行为识别算法。首先,通过杂波抑制及距离补偿方法获取高信噪比的人体行为距离像。其次,基于距离像提取目标时域特征,与频域特征进行融合,构建数据集。最后,基于支持向量机(support vector machine,SVM)算法对人体行为进行识别。实验结果表明,所提算法对于IR-UWB穿墙雷达人体行为识别能够达到95%的准确率。

MODIFIED ULTRA WIDEBAND CIRCULAR PRINTED MONOPOLE ANTENNA

A simple and compact microstrip-fed ultra wideband （UWB） printed monopole antenna is presented. The antenna is composed of a circular radiator and a finitely grounded plane. The antenna occupies about 16.62 GHz absolute bandwidth and 142.7% relative bandwidth covering from 3.38 GHz to 20 GHz with voltage standing wave ratio （VSWR） below two. A quasi-omnidirectional and quasi-symmetrical radiation pattern in H plane is obtained in the whole bandwidth. The high performance of the antenna is validated with measured and simulated results given. The antenna can be applied for the system design of UWB wireless communication.

融合全局与局部特征的UWB雷达人体动作识别算法

为了消除雷达信号中杂波和噪声对人体动作识别的干扰,提高小样本数据下动作识别的精度,在去除杂波及噪声干扰的基础上,提出一种融合全局与局部特征的超宽带(ultra-wideband,UWB)雷达人体动作识别算法。用动目标指示(moving target indication,MTI)结合自适应中值滤波对雷达原始回波信号进行预处理,再对人体动作的雷达二维特征图像利用主成分分析(principal component analysis,PCA)提取主要分量作为全局特征表征,并用二维离散小波变换(2D discrete wavelet transform,2D-DWT)结合奇异值分解(singular value decomposition,SVD)获取特征图像在不同方向与尺度划分下动作的局部特征表征,并将全局与局部特征进行串联融合;根据融合特征,在网格搜索算法(grid search,GS)优化的支持向量机(support vector machines,SVM)模型中实现人体动作的识别分类。实验结果表明,该算法能有效获取雷达信号中的人体动作信息,平均识别准确率为95.63%,具有良好的识别性能。

利用科赫分形解耦的四端口紧凑型QSC UWB MIMO天线

提出一种利用共面波导(Coplanar Waveguide,CPW)馈电的四端口紧凑型准自互补(Quasi-self-complementary,QSC)超宽带(Ultra-Wideband,UWB)多输入多输出(Multiple-input Multiple-output,MIMO)天线。此UWB MIMO天线的整体尺寸为40 mm×30 mm×0.8 mm,由4个六边形准自互补辐射单元对称排列而成,印刷在介质板的一侧。介质板另一侧印刷科赫分形解耦枝节和新型正六边形双开口谐振环(double-split ring resonator,DSRR)阵列,分别提升低频和高频处天线单元间的隔离度。实验与测试结果表明,此天线的工作带宽为3.1 GHz~15.5 GHz,在大部分工作频段内,隔离度达到20 dB以上。此外,天线在整个工作频带内具有良好的辐射特性和稳定的增益。包络相关系数小于0.04,表明该天线能够很好地满足极化分集特性,可用于便携式UWB MIMO无线通信系统。

Ultra-wideband bilateral tapered slot-line antenna fed by coplanar waveguide

In order to broaden the bandwidth of a tapered slot- line antenna （TSA）, a bilateral tapered slot-line antenna （BTSA） with a new feeding structure of coplanar waveguide （CPW） is developed. Based on the fact that the bandwidth limitation of TSA mainly depends on its feeding structure, an improved CPW-based feed structure etched on the backboard of the BTSA is adopted to perform traveling-wave transition. Both the simulation results and measurement data verify that the proposed feeding structure results in ＂high-pass＂ frequency response for antenna impedance matching. The voltage standing wave ratio （VSWR） is less than 2：1 when the frequency is higher than 3 GHz. The antenna gain exceeds 7 dBi with good radiation patterns when the bandwidth is from 4 to 16 GHz. This ultra wideband （UWB） antenna with a compact size is specially available for the electronic systems of counter-measure and microwave imaging.

利用UWB校正LiDAR SLAM的室内组合定位方法

针对室内定位中激光雷达(LiDAR)即时定位与地图构建(SLAM)算法误差会随时间累积以及超宽带(UWB)定位的结果较为分散的问题,提出了一种利用UWB观测值来校正LiDAR SLAM的组合定位方法。首先,通过里程计预测模型得到先验的位置估计信息;之后,利用粒子滤波融合LiDAR的观测值进行修正得到局部定位结果;最后,通过高斯滤波利用UWB观测值进行校正得到全局定位结果。实验结果表明:组合定位系统有效消除了LiDAR SLAM的累积误差,并且轨迹相对于UWB定位更为平滑。

A Novel Ultra-Wideband Monopole Antenna with Band-Stop Characteristic

In this letter, a simple monopole antenna with variable band-notched characteristic for ultra wide band (UWB) function is proposed. Two L-shaped quarter-waveguide resonators coupled to the ground plane with two shorting tracks at the sides of the antenna are used to generate stop-band performance around 5.5 GHz (WLAN). The proposed antenna is fabricated on the substrate FR4 (relative permittivity of 4.7) and has a compact size of 16 × 28.5 × 1.6 mm. The designed antenna has a good impedance matching in 3.1 - 11.4 GHz frequency range with VSWR < 2, except the band 5 - 5.85 GHz.

基于深度学习的UWB NLOS传播影响抑制技术研究

随着智能技术和设备的不断发展,精确定位技术在军事领域的应用越来越广泛,其应用场景涵盖室外和室内环境。全球卫星导航系统定位技术在室外环境中定位精度高,提供信息丰富,应用十分普遍。然而,由于墙壁、树木、玻璃等障碍物的遮挡,其在室内环境中的定位精度明显下降。超宽带技术以其定位精度高、时空分辨率强、传输速率快、成本低而显示出明显的优势。在室内环境中,各种障碍物使超宽带系统的基站和标签之间的传播通道被阻挡,由于超宽带信号的非视距传播现象,超宽带系统的定位精度明显下降。文中基于深度学习技术,提出了一种深度神经网络用于超宽带非视距传播影响抑制,该深度神经网络兼具ResNet网络和Non-local模块的优点,既可防止网络层数增加时网络性能不升反降的问题,也可捕获输入数据的全局特征,建立超宽带系统原始信道脉冲响应和测距误差之间的映射关系。相关实验结果显示,该方法可将超宽带系统在非视距传播条件下的测距平均绝对误差从0.1242 m降低至0.0681 m。与传统方法相比,该方法可消除人工统计超宽带信号波形特征耗费大量时间的缺点,可进一步提高超宽带系统在非视距传播条件下的定位精度,具有鲁棒性强、应用范围广的优点,可为军事领域室内高精度定位提供技术支撑。

3 - 10 GHz Ultra-Wideband Low-Noise Amplifier Using Inductive-Series Peaking Technique with Cascode Common-Source Circuit

The objective of this paper is to investigate a ultra-wideband (UWB) low noise amplifier (LNA) by utilizing a two-stage cascade circuit schematic associated with inductive-series peaking technique, which can improve the bandwidth in the 3-10 GHz microwave monolithic integrated circuit (MMIC). The proposed UWB LNA amplifier was implemented with both co-planer waveguide (CPW) layout and 0.15-μm GaAs D-mode pHEMT technology. Based on those technologies, this proposed UWB LNA with a chip size of 1.5 mm x 1.4 mm, obtained a flatness gain 3-dB bandwidth of 4 - 8 GHz, the constant gain of 4 dB, noise figure lower than 5 dB, and the return loss better than –8.5 dB. Based on our experimental results, the low noise amplifier using the inductive-series peaking technique can obtain a wider bandwidth, low power consumption and high flatness of gain in the 3 - 10 GHz. Finally, the overall LNA characterization exhibits ultra-wide bandwidth and low noise characterization, which illustrates that the proposed UWB LNA has a compact size and favorable RF characteristics. This UWB LNA circuit demonstrated the high RF characterization and could provide for the low noise micro-wave circuit applications.

Ultra Wideband Microstrip Diamond Slotted Patch Antenna with Enhanced Bandwidth

An Ultra Wideband (UWB) microstrip diamond slotted patch antenna with enhanced bandwidth is presented in this paper. The proposed antenna is simulated in CST Microwave Studio and fabricated for measurements. Its simulated result displays impedance bandwidth from 3.28 GHz to 19.64 GHz, whereas the measured result displays the frequency region from 2.01 GHz to 18.67 GHz. The antenna complies with the return loss of S11 < –10 dB and Voltage Standing Wave Ratio (VSWR) < 2 throughout the impedance bandwidth. Details of the antenna design and related results such as phase angle, input impedance and radiation patterns are discussed in this paper. This antenna has surpassed the bandwidth of UWB requirement, which is from 3.1 GHz to 10.6 GHz, and exhibits good UWB characteristics.

Experimental Study of On-Body Radio Channel Performance of a Compact Ultra Wideband Antenna

In this paper, on-body radio channel performance of a compact ultra wideband (UWB) antenna is investigated for body-centric wireless communications. Measurement campaigns were first done in the chamber and then repeated in an indoor environment for comparison. The path loss parameter for eight different on-body radio channels has been characterized and analyzed. In addition, the path loss was modeled as a function of distance for 34 different receiver locations for propagation along the front part of the body. Results and analysis show that, compared with anechoic chamber, a reduction of 16.34% path loss exponent is noticed in indoor environment. The antenna shows very good on-body radio channel performance and will be a suitable candidate for future efficient and reliable body-centric wireless communications.

A NOVEL ULTRA WIDEBAND MONOPOLE ANTENNA WITH BAND-NOTCHED CHARACTERISTICS

A simple and compact microstrip-fed Ultra WideBand(UWB) printed monopole antenna with band-notched characteristic is proposed in this paper.The antenna is composed of a square ring with a small strip bar,so that the antenna occupies about 7.69 GHz bandwidth covering 3.11～10.8 GHz with expected band rejection from 5.12 GHz to 5.87 GHz.A quasi-omnidirectional and quasi-sym-metrical radiation pattern is also obtained.This kind of band-notched UWB antenna requires no ex-ternal filters and thus greatly simplifies the system design of UWB wireless communication.

Ultra-Wideband Log Periodic Dipole Antenna (LPDA) for Wireless Communication Applications

This paper proposes a printed log-periodic dipole antenna (LPDA) for ultra wide bandwidth (UWB) applications. The antenna comprises of cascading four U shaped elements of different line lengths with balun circuit to improve the antenna impedance matching. The proposed antenna dimensions are 50 × 50 mm2 with FR4 substrate thickness 0.8 mm. Full-wave EM solver HFSS (High Frequency Structure Simulator) is used for modeling the proposed antenna. The pulse distortion is verified by the measured the proposed antenna performance with virtually steady group delay. The simulation and experimental results show that the proposed antenna exhibits good impedance matching, stable radiation patterns throughout the whole operating frequency bands, acceptable gain and stable group delay over the entire operating band. An UWB extended from 1.85 GHz to 11 GHz is obtained, and the average antenna gain is about 5.5 dBi over the operating band with peak gain around 6.5 dBi and 70% average radiation efficiency.

Link Budget Design with Performance Evaluation of Tunable Impulse-Based Ultra Wideband to Support the Integration of Wireless Sensing and Identifications Infrastructures

Recently, many studies propose the use of ultra-wideband technology for passive and active radio frequency identification systems as well as for wireless sensor networks due to its numerous advantages. By harvesting these advantages of IR-UWB technology at the physical-layer design, this paper proposes that a cross layer architecture platform can be considered as a good integrator for different wireless short-ranges indoor protocols into a universal smart wireless-tagged architecture with new promising applications in cognitive radio for future applications. Adaptive transmission algorithms have been studied to show the trade-off between different specific QoS requirements, transmission rates and distances at the physical layer level and this type of dynamic optimization and reconfiguration leads to the cross-layer design proposal in the paper. Studies from both theoretical simulation and statistical indoor environments experiments are considered as a proof of concept for the proposed architecture.