数据广播系统

RDS是为了在广播中传输附加信息而设计的。本文介绍了调频立体声广播实现RDS的技术、发展和标准化,闸述了其信号的产生、接收、可传输信息及其编解码。     

基于广播数据系统的城市公交广告信息传输

广播数据系(RDS)是一种利用调频多工技术对现有的调频广播系统进行改造,使用调频广播的剩余频带实现数据广播的方案.通过分析RDS的基本数据结构,介绍了将传统的循环冗余校验(CRC)运算转化为三字节递推算法并采用查表法进行快速计算,在有限的运算速度和资源的前提下实现RDS数据组同步运算的方法和程序流程,以及如何利用RDS透明数据通道进行城市公交广告信息的传输等内容.     

基于RDS和SCA技术的气象预警信息发布系统

为解决广大农村和偏远山区气象预警信息发布"最后一公里"问题.实现预警信息大范围覆盖.论文利用目前技术成熟、覆盖面广的无线广播系统作为通信媒介,利用调频多工技术在RDS信道和SCA信道传输预警信息,并研制开发出具有RDS解码功能的专用预警接收机,可实现预警信息自动触发和语音播报,建立起气象预警信息发布系统,提高了预警效果和预警覆盖面.     

DSP实现调频高速数据广播解调——软件无线电的解码器方案

一、调频高速数据广播系统(FMHDS) 调频高速数据广播系统是一种新型的数据广播系统,类似于早先的RDS(RADIO DATA SYSTEM)系统,但提供更高数据传输速率。利用调频基带的70KHz±9.1KHz范围的频率,可与立体声广播及RDS兼容,在一个调频信道中同时播出。系统采用DQPSK调制以17.5/28Kbps两种可选速率传输数字化信息,可传输文字、数据、声音和静止图象等。 调频高速数据广播系统由发送端的播出控制设备和编码器、射频链路,用户端的调频接收机和接收处理设     

调频多工数据广播接收技术的研究

信息科技的发展使得既能传输声音信号又可传送数据信号的调频多工数据广播的应用范围不断扩大.其中,广播数据系统(RDS)具备良好的抗干扰性且经济效益突出.本文在对当前RDS技术的一般参数、调制方式等进行介绍的基础上,从系统的硬件整体设计角度论述了其接收部分的设计方案和主要功能器件的选型,并分析了主要硬件电路的设计,具有实际的应用价值.     

调频多工数据传输技术在交通诱导系统中的应用

针对我国智能型交通的现状,分析了基于调频多工数据传输技术的交通诱导系统。在研究RDS-TMC技术的基础上,设计了利用RDS技术传输实时交通信息的车载动态导航装置,并介绍了该装置的主要功能模块。     

GPS与RDS在汽车资讯机中的联合应用

<正> 全球定位系统(GPS,global position system)已广泛应用于地图识别、集群调度和工商监察等诸多领域,无线电数据系统(RDS,radio data system)是指利用无线电广播系统的亚频发送数字数据,本文描述GPS与RDS在汽车资讯机(auto res commu-nication system)中的一种联合应用。总体设计思想是把城市地图、路口号信息和停车场号信息预先存入数据库,汽车资讯机上显示的当前位置随GPS上接收到的经纬度而变化,根据经纬度从数据库中取得当前位置附近的路口号和附近停车场号,由RDS解码得到的最新情况不断更新内存中的路口忙闲信息和停车场车位信息,同时还可通过RDS传送其它信息,如股市行情和声文同步信息等。     

基于RDS的实时交通信息接收系统

本文介绍了RDS技术的发展及系统原理,描述了RDS系统的数据编码规则,着重介绍了实时交通信息RDS-TMC,说明了标准TMC数据报文的内容及解析后可提供的交通信息内容。提出基于RDS技术构建实时交通信息接收系统设计方案,给出了典型系统的功能构架图示,介绍了系统各主要功能模块,说明了实时交通信息数据的应用和作用。     

基于S1473X的RDS功能设计与实现

介绍了RDS功能在车栽音响系统中的应用与实现,并设计低功耗硬件电路以适应车载供电的要求。RDS功能采用S1473X嵌入式芯片实现,通过软件编程实现了带RDS的数字调频立体收音功能,为车载音响系统提供调频接收和RDS信息服务。通过平台测试,证明是一种廉价可行的解决方案。     

湖北省农村智能广播网建设技术方案

目前,全国已有多个省、市、区已经建成或正在建设农村广播系统。本文从系统架构、调频RDS数据传输、安全保障三个方面阐述了湖北省农村智能广播网建设技术方案。     

Spectrum efficiency of radio data system (RDS)

The paper addresses the use of the radio data system (RDS) for datacasting road traffic information. It is concluded that, although RDS may be essential to the early phases of introduction of novel advanced traffic information systems (ATISs), FM subcarrier transmission does not offer a spectrum-efficient solution for large-scale ATIS datacasting. The conclusions are believed relevant to the spectrum-efficient design of the future datacasting networks     

Analysis of new methods for broadcasting digital data to mobileterminals over an FM-channel

Two new methods using an FM-radio channel for transmission of digital data to mobile terminals are examined: 1. A modification of the radio data system (RDS). In RDS, additional digital information is multiplexed with a stereo sound signal. A new system is suggested where the data signal can be multiplexed with a mono audio signal. This causes extension to the bandwidth available for the data signal, and therefore the RDS bitrate can be increased. Error calculations are performed both for the original RDS system and for the new system. 2. Orthogonal frequency division multiplexing (OFDM). OFDM is used in the digital audio broadcasting system (DAB), which is designed to transmit digital audio in the FM band. In OFDM a signal is divided over a large number of 2- or 4-PSK modulated orthogonal subcarriers. The subcarriers of 6 different programmes are multiplexed in one beam to reduce the effects of frequency selectivity of the transmission channel. A new system based on OFDM is proposed, in which the carriers of each programme are transmitted in one FM-channel with a bandwidth of 200 kHz instead of multiplexed with the carriers of other programmes. Error calculations are performed for the subcarriers used in the OFDM modulation method     

RDS-the way ahead for radio

The author describes the background to RDS (radio data systems) which enable the listener to `programme' a radio to hunt for news or travel information and eliminate the need for manual retuning. The author discusses static and dynamic RDS and the design of radios for the system     

一种调频广播数据接收显示系统的设计

针对公路隧道对电子信息牌的需求,以RDS/RBDS为通信方式,采用工业级MCU和专用RDS/RBDS接收解码芯片,结合LED显示屏技术,设计了一个公共信息显示系统。主要介绍了接收显示系统的原理,重点阐述了RDS接收器的软、硬件设计方法和系统相应的通信协议;该设计已应用于城市公路隧道中。实践表明,该设计具有成本低、覆盖范围广、实用性强等特点。     

DC-free binary convolutional coding

A novel DC-free binary convolutional coding scheme is presented. The proposed scheme achieves the DC-free coding and error-correcting capability simultaneously. The scheme has a simple cascaded structure of the running digital sum (RDS) control encoder and the conventional convolutional encoder. A given sequence becomes DC-free if and only if the absolute RDS value of the sequence is bounded by a constant for any time instant. The RDS control encoder generates a sequence which gives the convolutional-coded sequence with a bounded RDS value. The structure allows us to exploit efficient soft-decision decoding which attains additional coding gains compared with hard-decision decoding over an additive white Gaussian noise (AWGN) channel. Bounds on the RDS value are explicitly established for the proposed scheme. By using the bounds, we have performed computer searches for finding good RDS control encoders. The proposed scheme provides wide varieties of reasonable tradeoffs between the coding gain, the RDS constraint, and decoding complexity. For example, a 64-state DC-free coding scheme with the overall rate 6/16 and the minimum free distance 10 has been obtained. This scheme satisfies a bounded RDS constraint (from -18 to +18) and it yields a considerably high asymptotic coding gain (over an AWGN channel) of 5.7 dB     

基于网络的城市交通信息系统分析与设计

智能交通系统提供路况、拥塞、事故、安全等各种交通信息和旅客需要知道的各种服务信息,基于此利用GPS定位采集、道口传感器、路口摄像机、RFID卡等多种现代化的采集方式使车辆、道路智能化,达到缓解道路拥堵、减少交通事故、节约能源的目的。     

RDS远程数据访问技术研究

基于网络的计量测试系统需要解决的问题之一就是远程数据访问。对ADO的RDS的对象模型和编程模型进行研究,阐述RDS的功能和特点,研究RDS数据访问技术的具体实现方法,分析RDS的安全性并提出相应的解决方案。作为一种先进的数据访问技术,RDS能为计量测试系统远程数据访问提供有力的技术基础。     

RDS技术原理与接收机电路设计

介绍了一种在普通FM广播信号中增添数字信号的技术——RDS(Radio Data System)技术。首先详细描述了RDS的技术原理与标准,在此基础上又给出了可靠的收发电路设计方案。     

Reaction mechanisms of tertiarybutylarsine on GaAs (001) surfaces and its relevance to atomic layer epitaxy and chemical beam epitaxy

We explore the use of tertiarybutylarsine (TBAs) as an alternative arsine source in atomic layer epitaxy (ALE) of GaAs. X-ray photoelectron spectroscopy (XPS), reflection high energy electron diffraction (RHEED), and reflectance difference spectroscopy (RDS) are used to characterize the surface reactions of TBAs on GaAs (001) Ga-rich surfaces. At a substrate temperature of 320° C and an exposure level of 90 L of TBAs, AsH_x (x = 1 or 2) is thought to be the adsorbed arsenic species. As the substrate temperature increases, As-rich surfaces are readily obtained with improved RHEED 2 x 4 patterns. No carbon related species are observed throughout the TBAs exposure experiments between 320° C and 540° C. It is suggested that AsH_x is the adsorbed species after TBAs decomposes on surface Ga atom. Interactions between AsH_x pairs form arsenic atoms by H₂ release. RDS allows anin-situ real time study of TBAs on GaAs (001) Ga-rich surfaces. It is found that the RDS results are consistent with those obtained from XPS and RHEED investigations and can provide information on the rates of reactions and the extent of surface reconstruction simultaneously. Implications for the growth of GaAs by atomic layer epitaxy and chemical beam epitaxy using TBAs are discussed.