IEEE Transactions on Communication Technology最新文献_第5页

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089656

O. Leneman

引用次数: 2

An Extended Analysis of RF Interference in FDM-FM Radio Relay Systems FDM-FM无线电中继系统中射频干扰的扩展分析

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089654

G. Garrison

{"title":"An Extended Analysis of RF Interference in FDM-FM Radio Relay Systems","authors":"G. Garrison","doi":"10.1109/TCOM.1967.1089654","DOIUrl":"https://doi.org/10.1109/TCOM.1967.1089654","url":null,"abstract":"In a conventional microwave receiver a number of critical frequencies exist such that, when an interfering RF signal is introduced in their vicinity, a spurious IF response results. The existing methods for computing intermodulation due to an interfering carrier are found to be only partially satisfactory, in that, they do not explicitly define the manner in which the receiver mixing mechanism modifies the RF interference with respect to the level relative to that of the wanted carrier, frequency displacement in the IF from the primary IF response, and modification of the modulation index of the interference modulation. This paper extends, in a general manner, the theories of RF interference to include interfering signals falling on or near all major critical frequencies of the receiver. It is shown that, with the relative conversion efficiencies of the mixer available from empirical data and an understanding of the manner in which the mixer will modify the frequency displacement and modulation index of the interfering signal, these interference situations can be analyzed within the scope of a previously defined general interference equation. As an illustrative example some interference problems in a 1200-channel system are analyzed and substantiated with measurement data.","PeriodicalId":134522,"journal":{"name":"IEEE Transactions on Communication Technology","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1967-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125012355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

On the efficient use of voice-channel bandwidth in data transmission 数据传输中语音信道带宽的有效利用

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089649

F. Amoroso

引用次数: 1

Categorization of Multiple-Access/Random-Access Modulation Techniques 多址/随机接入调制技术的分类

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089648

J. Wittman

引用次数: 13

Design Studies for Reliable Long-Range Ground-to-Air Communication 可靠的远程地对空通信设计研究

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089650

A. Ince, H. Williams

{"title":"Design Studies for Reliable Long-Range Ground-to-Air Communication","authors":"A. Ince, H. Williams","doi":"10.1109/TCOM.1967.1089650","DOIUrl":"https://doi.org/10.1109/TCOM.1967.1089650","url":null,"abstract":"Design parameters of UHF/VHF ground-to-air communication systems are discussed with particular reference to propagational reliability. Included are results of some flight trials made over Western Europe using UHF transmissions to four different ground locations with the object of studying the repeatability of signals and effect of different terrain conditions. These experiments were performed under winter conditions when signal variability due to atmospheric refraction was much reduced. In many cases, the plot of field strength vs. distance differed markedly from the theoretical smooth-earth value. However, near the optical horizon the field strength obtained was in reasonable agreement with the theoretical value at all four locations. The fading recorded at long range was no greater than about ±1dB. Both from theoretical arguments and from experimental results, it seems that only the near-in part of the first Fresnel zone is important. The Fresnel zones do not have the same significance as in the usual optical case. Experiments showed that, even in the case of a very irregular foreground, the field at extreme ranges was relatively unaffected. The dominating factor for long-range communication is therefore the degree of atmospheric refraction. By using a known probability distribution of the atmospheric refraction, it is possible to construct curves showing the probability of obtaining a given range with a particular set of system parameters. The paper concludes with curves of this nature for frequencies of 40, 120, and 300 MHz, and for a variety of antenna heights.","PeriodicalId":134522,"journal":{"name":"IEEE Transactions on Communication Technology","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1967-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125673394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Intermittent Binary Communications in a Rayleigh Fading Medium 瑞利衰落介质中的间歇二进制通信

IEEE Transactions on Communication Technology Pub Date : 1967-10-01 DOI: 10.1109/TCOM.1967.1089659

J. Martin

引用次数: 0

Intermodulation Noise of FDM-FM Communications Through a Hard Limiter 通过硬限制器的FDM-FM通信互调噪声

IEEE Transactions on Communication Technology Pub Date : 1967-08-01 DOI: 10.1109/TCOM.1967.1089634

J. Spoor

引用次数: 4

Design of Block-Coded Communication Systems 分组编码通信系统的设计

IEEE Transactions on Communication Technology Pub Date : 1967-08-01 DOI: 10.1109/TCOM.1967.1089629

W. Lindsey

{"title":"Design of Block-Coded Communication Systems","authors":"W. Lindsey","doi":"10.1109/TCOM.1967.1089629","DOIUrl":"https://doi.org/10.1109/TCOM.1967.1089629","url":null,"abstract":"The design and performance of frequency multiplexed, phase-modulated communication systems is presented. In particular, the transmitter is assumed to be an ideal phase modulator which modulates a RF carrier withNphase-modulated, sinusoidal data subcarriers, and in general,Mbinary-valued composite signals. The receiver is a superheterodyne phase-locked loop (PLL) whose output is applied to one ofNsubcarrier extractors. Each subcarrier extractor consists of a subcarrier tracking loop, a timing loop, and a data detector which operates as a cross-correlator. The paper presents results which allow the design engineer to allocate the total power betweenNmodulated data subcarriers,Mbinary-valued signals, and the carrier signal. The total power in the distortion component is computed. Finally, a method is given which allows the communications engineer to select the data rate and the modulation factor of each data subcarrier which will minimize the probability that the data detector will err in the decision process. The results are sufficiently general so that they may be used in designing block-coded systems. Such systems have application in various branches of aerospace communication engineering, e.g., channelized communication satellites and deep-space probes.","PeriodicalId":134522,"journal":{"name":"IEEE Transactions on Communication Technology","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1967-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123552445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

A 160-Watt Experimental Thermoelectric Power Plant for Telephone Microwave Equipment 用于电话微波设备的160瓦实验热电发电厂

IEEE Transactions on Communication Technology Pub Date : 1967-08-01 DOI: 10.1109/TCOM.1967.1089636

T. Plevyak

引用次数: 2

Measurement of the Phase Constant for Rock Propagated Radio Signals 岩石传播无线电信号相位常数的测量

IEEE Transactions on Communication Technology Pub Date : 1967-08-01 DOI: 10.1109/TCOM.1967.1089639

C. Tsao, J. Debettencourt

引用次数: 12