光纤材料的研究进展

本文简要介绍了光纤材料的种类，制造方法及研究进展。     

日本移动通信频率选择技术动向

本文介绍日本在移动通信中频率选择的技术动向以及开展移动通信频率资源的几项措施。     

计算机总线的发展趋势

本文着重介绍世界上目前最流行的几种计算机总线的情况，以及今后的发展趋势。     

IC卡在电信领域的应用模式

本文列举了ＩＣ卡在电信领域及一些国家和地区的应用之后，给出了国际ＩＣ卡的应用发展模式，以供有关部门参考。     

具有多普勒频移校正功能的DQPSK调制解调器

本文介绍了一种适合于卫星移动通信的具有多普勒频移校正功能的ＤＱＰＳＫ调制解调器及其ＤＳＰ实现，给出了多普勒频移校正方法，提出了在大多普勒频移情况下的跟踪滤波器方法。实验测试表明，该调制解调器实现恶化小于１ｄＢ（输出误比特率Ｐｂ＝１×１０－４时，对应的Ｅｂ／ｎ０＝１１．６ｄＢ）。多普勒频移在－Ｒｓ／２～Ｒｓ／２内变化时，对Ｐｂ没有影响。多普勒频移速率可达１００Ｈｚ／ｓ，这里Ｒｓ是已调信号的符号速率。     

DS／FH／TH混合扩频系统抗干扰性能的计算机模拟

在扩频通信中,抗干扰性能是评价扩频通信体制优劣的重要指标。本文研究DS/FH/TH混合扩频系统的抗干扰性能,建立了系统模型及计算机模拟方案,通过计算机模拟获得了在连续波、脉冲波多音干扰、部分带宽干扰、脉冲噪声干扰情况下的系统误码率曲线,具有一定的实用价值。     

RECOGNITION OF MODULATION SYSTEM IN COMMUNICATION

Recognition of modulation system is an important problem in the modern electronicreconnaissance.A general method for solving this problem is suggested in this paper.From asegment of a captured signal we can determine the modulation system and extract its parameterwith this method.The theoretical basis,algorithms and test results of this method are described.It has been proved that the method is very effective in practical situation.     

Real-time Parallel Processing System Design and Implementation for Underwater Acoustic Communication Based on Multiple Processors

ADSP-TS101 is a high performance DSP with good properties of parallel processing and high speed. According to the real-time processing requirements of underwater acoustic communication algorithms, a real-time parallel processing system with multi-channel synchronous sample, which is composed of multiple ADSP-TS101s, is designed and carried out. For the hardware design, field programmable gate array （FPGA） logical control is adopted for the design of multi-channel synchronous sample module and cluster/data flow associated pin connection mode is adopted for multiprocessing parallel processing configuration respectively： And the software is optimized by two kinds of communication ways： broadcast writing way through shared bus and point-to-point way through link ports. Through the whole system installation, connective debugging, and experiments in a lake, the results show that the real-time parallel processing system has good stability and real-time processing capability and meets the technical design requirements of real-time processing.     

CAN总线通讯协议设计

通过对CAN通讯系统需要分析,可确定CAN通讯系统的通讯周期、工作方式、码速率.其约束条件包括系统工作周期、通信协议约束、通信格式约定、多字节数据及位标记.分析各个数据的优先级与传输途径确定编码规则,制定CAN通讯协议,可建立高效可靠的CAN通讯系统.     

40 Gbit/s packet bit error ratio and loss real-time measurement for ultrahigh-speed packet switched network

A novel packet bit error rate (BER) and loss measurement method and system is proposed. A proposed 40 Gbit/s packet BER and loss measurement system is expressed in detail. A 40 Gbit/s BER and loss measurement with various conditions is demonstrated experimentally. In real time, only the payload part of a packet and burst stream with fluctuated guard time is evaluated. The BER and packet loss of a randomly received packet sequence due to routing and buffering can be also evaluated by the measurement system. A 10 Gbit/s packet BER and loss measurement with optical label switching, buffering, and preamble-free optical packet 3R are demonstrated experimentally.