基于水声的水下无线通信研究

介绍在水声随机多途径传输的信道中, 基于水声的水下无线通信的方法及其实现. 海洋环境 的水声信道不仅是一个极其复杂的时—空—频变随机多途径传输信道, 尚有环境噪声高、带宽窄、载 波频率低、传输延时大等因素制约数据传输速率. 介绍的通信方法及支持实现的关键技术, 都对这些 方面的影响予以考虑. 做出的语音、图像以及数据3 种不同的应用系统, 多数已通过海上实验, 效果 良好, 可实际应用. 并指出国际上技术先进的国家致力这领域研究的也仅在最近才有极少数取得重 大突破, 该结果展示它与国际近于同水平同步地进展.国家“863”计划(8632512211224, 8632512211226, 8632512204207) 和福建省自然科学基金 (A 9910001) 资助项

超声传输特性和超声传感系统研究

研究了空气介质中超声波的辐射、传播、散射和接收等规律性, 作为超声传感系统设计的理 论基础和具体参数选择的依据. 简述3 种具有创新性的超声传感系统: 混凝土喷射机械手超声测距 测向系统、超声地形障碍检出传感系统和移动机器人超声传感系统的设计和实验结果等.国家863 计划(8632512210221) 和国家自然科学基金(69385006) 资助项

A ULTRASONIC NAVIGATION SYSTEM FOR MOBILE ROBOT

本文设计了一种用于移动机器人的超声波导航系统，介绍了系统的工作原理及结构，并进行了样车实验．实际的导航实验表明：系统可用于室内结构环境中的移动机器人导航．The design, work principle and system construction of a ultrasonic navigation system of mobile robot are presented in this paper. Practical navigation experiments on demo robot show that it can meet the need of mobile robot working in constructive environment

Genetic algorithms based LMS adaptive time delay estimation of ultrasonic signal

为了克服LMS自适应时延估计（LMSTDE）算法计算量大的问题，引进遗传算法进行LM－STDE的寻优规划，并采取了克服过早收敛的措施。对超声信号进行时延估计的实验表明，该方法大大减少了计算量，并有较高的时延估计精度。To cut down the amount of computation of LMSTDE method, Genetic algorithms with special measures to overcome immature constringency is employed for optimazing search process of the LMSTDE. The experimental results of Ultrasonic ranging system show that.while keeping high TDE precision, this method can greatly reduce computation amount.国家863计划资助!512－10－2

The Applicaton of PDC-DTACAA to Signal Detection in Shallow Water Acoustical Channel

从幅域、频域和时域上，分析了采用脉宽编码调制-数字时间自相关积累（PdC-dTA-CA）于浅海声信道的可行性。初步估算了系统的虚警概率Pf、检测概率Pd及其与输入信噪比的关系。理论分析和实验证明：PdC-dTACA能适应于复杂的浅水声信道低速率数据传输。The Feasibility using the PDC-DTACA scheme in shallow water channel isanalysed.Theoretical estimations and experimental results,show that the scheme can be used inthe channel For underwater acoustical telemetry at the low datd rate

High-rate data transmission techniques in underwater acoustic channels

本文介绍近年来水声信道高速率数据传输技术的一些研究进展，并结合本所研究的水声数据遥测，数字语音通讯和视频图象传输实验样机，讨论了具有抗多途干扰的声传输系统在调制信号设计及信号处理上所采用的关键技术。Recent certain advances in high-rate data transmission techniques in underwater acoustic channels are introduced.By presenting the prototypes of underwater telemetry and telecontrol, underwater digital acoustic communications, underwater visual image transmission which we have studied and implemented, the key techniques of an anti-mutipath acoustic transmission system in the choice of signal design and signal processing are discussed.国家八六三计划智能机器人主题资助!863-512-11-2

An Ultrasonic Navigation System Used for Automatic Guided Vehicle

设计了一种用于自动导引车 (AGV)的超声波导航系统 ,介绍了系统的工作原理及结构 ,并进行了各项导航功能的样车实验。实验数据表明 :系统可适应AGV的工作特点 ,可用于CIMS中固定及自由路径模式的AGV。The design, work princeple and system construction of a ultrasonic navigation system of mobile robot are present. Practical navigation experiment on a demo AGV shows that it can meet the need of AGV.86 3计划 ( 86 3 5 12 10 2 17)资助项

Wavelet transform and adaptive algorithm based FIR equalizer

研究了基于小波变换的FIR（WFIR）横向滤波器进行换能器均衡的处理方法，并以LMS自适应算法构造WFIR系数。实验表明；与传统的FIR及IIR结构均衡器相比，该方法具有均衡效果好、计算量小的特点。This paper introduces transducer equalization method using wavlet transform based FIR (WFIR) transversal filter, and employing LMS adaptive algorithm to construct WFIR filter's weights. Experimelit shows that: compared to traditional FIR and IIR mode equalization, this method can get better equalization results while keeping low computational burden.福建省自然科学基金!F981000

A Processing Method with High Precision forUltrasonic Distance Measurement

根据声的发射、反射及传输理论推出并用实验验证了测距回波包络曲线的近似方程，据此提出了一种高精度超声波测距信号处理方法.介绍了以单片机实现该方法的超声测距系统，该系统在2.5~12M范围内测距误差不大于0.25%.Based on the theory of ultrasonic′s launching, reflecting and transmitting, an approximate equation descrbing the envelope of reflecting signal is derived and then verified experimentally.After that,a highaccuracy detection processing method is presented and a practical system realized with a 8051 single chip microcomputer is introduced.Distance measurement tests between 2.5 ～12 m show that its accuracy is satisfied.国家863计