基于MSP430单片机的窄带无线数据传输模块的设计

针对窄带无线电台模拟信道传输数据信息所存在的局限性问题,研究设计了基于MSP430单片机为核心的窄带无线数据传输模块,充分利用MSP430系列单片机的主要特点功能,分析研究窄带无线数据传输模块的基本组成结构和部分硬软件设计技术方案。在通信电路、数据处理、调制解调、电源管理和抗干扰及传输距离等方面做了较深入的研究探析,实现在短波、超短波窄带无线电台的模拟信道上进行较高速率的数据通信,提高了信息传输的速度,增大了信息传输的容量,增强了信息传输的可靠性,为窄带无线数据通信系统的研究应用及发展提供了重要的指导作用。     

窄带通信综合业务的传输实现

窄带通信具有信道资源有限的特点,采用统一信元封装传输各种业务能够充分利用信道资源。阐述了话音线路倍增技术的概念,提出了将线路倍增技术应用于异步数据传输的思想,介绍了传真通信的特点。基于上述原理给出了窄带综合业务适配器的方案实现,对设备的各个组成部分从硬件和软件2方面进行了论述。最后提出了该设备应用点点通信和网间通信的方案,分析了2种方案的特点和性能,并展望了窄带通信综合业务适配器的发展前景。     

PSAA60W/60M-480：48V输出适配器

Phihong公司为其现有的PSAA60W和PSAA60M单输出适配器系列推出48V输出适配器。这两个系列的适配器已包括12、15、18和24V输出型号,PSAA60W-480两线输入适配器和PSAA60M-480三线输入适配器是两个新增型号。新的48V适配器更能满足网络、数据通信和IP应用的需要。     

高速无线电台在专用GPS无线数据通信网中的应用

该文介绍了美国MDS公司高速无线电台的技术特点,与其它产品与应用方式的比较,以及MDS产品在专用GPS无线数据通信网中有得天独厚的应用优势。     

软件无线电台自组网技术研究

本文对软件无线电台自组网的研究情况进行了概述,并介绍了一些关键技术的研究进展,包括网络控制管理、路由、网络资源共享、动态负载均衡、软件无线电台网互连等,描述了设计软件无线电台自组网所面临的主要问题,提供了进一步研究软件无线电台自组网的一种思路.     

基于C8051f040的CAN与SMBus协议适配器

设计了一种基于高性能C8051f040单片机的CAN与SMBus协议适配器系统.介绍了C8051f040单片机内部CAN控制器与SMBus协议的特点及适配器的工作原理,并给出了软硬件的设计思想和具体实现方法.实际测试表明:上位机通过该适配器系统与焊机进行数据通信,对数据进行处理,很好地实现了对汽车生产线焊机智能控制的目的.该系统具有抗干扰性好,工作效率高,使用方便等优点.     

基于蓝牙技术的火控检测系统无线网络的研究

针对部队特殊环境中装备检测的需要,提出了采用蓝牙技术组建火控检测系统微微网.本文在研究蓝牙无线网络结构的基础上,利用BluceCore4-External蓝矛模块,设计开发了蓝牙串口适配器,实现了微微网内点对点数据通信和广播数据,达到了网内资源共享,增加了检测的可靠性和简便性.     

海上遇险搜救综合通信系统的设计与实现

为了提高我国海上搜救应急反应的调度、指挥能力,利用现代通信、计算机、计算机电信合成(CTI)等技术,实现了海上遇险搜救综合通信系统.该系统采用程控调度交换和无线电台适配的方案,使用无线电台适配器将无线通信转换为有线通信,再通过程控交换机将各级海上搜救中各类卫星、语音电话、视频系统等异构终端综合互联,实现有线通信系统与无线通信系统的无缝连接,从而为值班和搜救指挥人员提供专业、便捷的通信、操作手段,提高指挥判断的准确性和效率.     

基于蓝牙技术的火控检测系统无线网络的研究

针对部队特殊环境中装备检测的需要,提出了采用蓝牙技术组建火控检测系统微微网。本文在研究蓝牙无线网络结构的基础上,利用BlueCore4-External蓝牙模块,设计开发了蓝牙串口适配器,实现了微微网内点对点数据通信和广播数据,达到了网内资源共享,增加了检测的可靠性和简便性。     

基于C8051F020的通用串口适配器的设计与实现

介绍了基于单片机C8051F020的通用串口适配器的设计与实现方法,即由单片机控制的智能化一对多口收发信号转换器.通过采用C51对单片机进行编程,控制与RS-232(标准RS-232电平)、RS232(TTL电平)、RS-422接口的数据通信;采用C Builder作为开发平台,通过RS-232接口实现上位机对适配器各个通信端口的控制.     

Compensation of a narrowband interference in an ultrawideband communication system based on chaotic radio pulses

The influence of narrowband signals on incoherent reception of ultrawideband chaotic radio pulses in direct chaotic communication (DCC) system is considered. A method for compensating the influence of narrowband signals on the characteristics of this system after incoherent reception of chaotic radio pulses is proposed. The proposed solution enables one to compensate a narrowband signal, preserving the possibility to determine chaotic radio pulses at corresponding time positions. The dependence of the probability of an error per bit on the spreading ratio of chaotic radio pulses is established.     

无线数传中频FSK Modem的研究

本文介绍单片集成锁相环NE564在无线数据通信中的应用,提出了能适用于80系列窄带VHF数据通信系统的一种方案,其中频采用10.7MHz,频偏量为±5kHz,组成2FSK制式的中频Modem,具有较高的性能价格比,工作性能可靠,速率可达2400波特。     

基于同步条件下短波宽带通信相关技术研究

现阶段短波通信主要针对频谱管理、信道选择以及波形设计等方面进行研究,用以支持比传统3kHz带宽更宽的短波通信信道。在同步技术越来越成熟的阶段,未来短波通信的主要研究方向将由窄带向宽带发展。该文主要针对短波通信的性质,分析短波通信在同步条件下宽带的优越性和可行性。     

WCDMA Downlink Coverage Reduction Due to Adjacent Channel Interference

This paper determines the coverage reduction of the Wideband CDMA (WCDMA) downlink in the case of interference, due to adjacent narrowband system. The coverage reduction has been evaluated in terms of blocking area around the interfering base station. The analysis takes into account different interference mechanisms and their individual effects to the coverage. The interference mechanisms which have been considered here are the out-of-band emissions of the base station transmitter, the adjacent channel interference due to non-ideal sideband filtering, the intermodulation and the crossmodulation. The coverage effects in realistic network environment have been computed by using accurate ray-tracing propagation models designed for the path loss calculation in the urban environment. In the numerical examples, the effect of GSM interference has been demonstrated, but the method can be utilized with other narrowband systems as well. The results can be utilized in radio system design, radio network planning (RNP) and the frequency allocation of the WCDMA systems.     

基于带内扩频技术的无线电台数字通信的设计与实现

提出了一种采用DS-GMSK体制、基于带内扩频技术的无线电台数字通信方案.分析了伪随机码的设计方法,阐述了扩频及解扩同步、纠错编码、GMSK等部分的实现方法,并给出了实现框图.该方案可方便地给以模拟方式作为语音通信的无线电台增加数据通信及保密通信功能,大大提高了电台的性价比.     

Spectrum sensing and communication functionalities verification in cognitive radio

This paper is intended to discuss hardware setup implementation for realizing the spectrum sensing and communication functionalities of a five‐port integrated ultrawideband and narrowband antenna system. The five‐port integrated antenna system consists of one ultrawideband antenna and four narrowband antennas. The ultrawideband antenna is used for spectrum sensing in cognitive radio, whereas the four narrowband antennas are used for communication. In order to validate functionalities of the antennas, their spectrum sensing and communication performance is verified using an arbitrary waveform generator, real‐time signal analyzer, and Universal Software Radio Peripheral. The ultrawideband antenna is able to sense the various frequencies transmitted by the arbitrary waveform generator. These transmitted signals from the arbitrary waveform generator are treated as busy spectrum channels in the cognitive radio environment. The narrowband antennas are able to perform communication by transmitting the signals at identified spectrum holes. The sensed signals are observed on a real‐time signal analyzer, and the communication signals are viewed in LabVIEW software for which a real‐time signal reception algorithm is used. This signal reception is performed using Universal Software Radio Peripheral.     

A cellular packet radio data network

A new wide-area data network is described. The network employs packet switching techniques within a multi-access, narrowband cellular radio environment and provides a flexible alternative to copper wire telecommunications for short data message applications. Following a discussion of the network requirements, the paper describes the key design areas in terms of a layered model. A new data link layer protocol called dynamic slotted reservation Aloha is introduced. This protocol is optimised for the bidirectional communication of packets containing around 1000 bits of application data. The practical implementation is presented briefly before a number of the major applications are discussed     

基于OFDM技术的短波通信电台研制

本文研究了OFDM调制技术在短波通信中的应用,提出了一个基于OFDM调制的短波通信电台的设计方案并完成了软硬件系统设计。对实验样机的测试结果表明,本系统性能指标能够满足实际要求。     

基于认知无线电的脉冲陷波UWB窄带干扰抑制

提出了一种基于认知无线电的自适应超宽带(UWB)窄带干扰抑制方法.为了使UWB对变化的干扰环境具有自适应调节能力,引入了认知无线电技术.通过频谱感知和认知引擎技术提取窄带干扰频谱特征作为陷波器的设计依据.以高斯脉冲为例,对陷波器的陷波性能进行检验.最后,就陷波前、后脉冲的通信性能进行比较.仿真结果表明:认知陷波脉冲具有...     

Design and performance analysis of an advanced, narrowbandintegrated voice/data mobile radio system

Private land mobile communications have experienced significant demand for increased capacity and for new services, but congestion within the currently allocated 450 and 800 MHz bands has severely limited the capability of present generation systems to meet this demand. This paper proposes a narrowband integrated voice/data mobile radio system which triples current voice traffic capacity and simultaneously provides capacity for mobile data communications such as mobile data terminals, automatic vehicle location, and mobile facsimile by utilizing the silence gaps inherent in speech. The system is designed to fit within the narrowband 25 kHz channels in the 450 and 800 MHz frequency bands, and thus the system can replace existing private land mobile radio systems with minimum impact. The centerpiece of the system design is an evolutionary multiplexing and access control technique known as Packetized Data, Voice Dedicated (PDVD) Burst Switching which allows transmission of data within the silence gaps inherent in speech. Simulation results for various voice and data traffic loads show the flexibility and efficiency of the proposed narrowband integrated voice/data mobile radio system