ISSN:0737-2884    

DOI:10.1002/sat.4600070102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractAn expression is derived that gives the output fundamental and intermodulation product magnitudes for an ideal hard limiter, for the case ofninput signals plus Gaussian noise. The expression is derived by building upon previous work by Shimbo4to account for the Gaussian noise input. The expression is implemented in a computational tool. Results are generated and are compared with data generated by Jain5for three‐signal suppression, and by Blachman11for the functional relationship between the output and input SNR for a bandpass limiter. In all cases, the data generated agree extremely well with published result

ISSN:0737-2884    

DOI:10.1002/sat.4600070103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThis paper reviews several objective definitions of compandor advantage, and singles out one which is directly related to subjective measurements available in the literature. An analytical expression for compandor advantage under this definition is derived, taking into account the presence of noise at the compressor input. Values of compandor advantage computed from this expression are compared with subjective measurements.

ISSN:0737-2884    

DOI:10.1002/sat.4600070104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractIn late 1986 details of the radio‐frequency signal structure currently employed by the pre‐operational GLONASS satellite navigation system were revealed by the Satellite Communications Group at Leeds University. Since then further investigation has resulted in a successful interpretation of most of the data message transmitted on the civil code, sufficient to allow the design and construction of a GLONASS receiver capable of the same level of performance as can now be achieved with NAVSTAR GPS. Details of the message content relating to location of GLONASS satellites for the purposes of position‐fixing and time‐referencing are presented for the fir

ISSN:0737-2884    

DOI:10.1002/sat.4600070105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThis paper provides estimates of the frequency of occurrence, duration and probability of satellite EHF communication outages due to attenuation by rain. These can be used to determine optimum frequencies, power levels and the need for space diversity of terminals or other alternatives to maintain reliable communications. Ten years of 1 min rain rates at each of 12 U.S. cities were used in conjunction with an attenuation model to quantify communication outages at locations representing a variety of climatic regimes. Analyses of the 1 min rain rates and outage estimates at 10, 30 and 45 GHz for elevation angles of 10°, 30°, 50° and 70° are presen

ISSN:0737-2884    

DOI:10.1002/sat.4600070106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThis paper reviews the effects of precipitation on earth‐space communication links operating the 10 to 35 GHz frequency range. Emphasis is on the quantitative prediction of rain attenuation and depolarization. Discussions centre on the models developed at Virginia Tech. Comments on other models are included as well as literature references to key works. Also included is the system level modelling for dual polarized communication systems with techniques for calculating antenna and propagation medium effects. Simple models for the calculation of average annual attenuation and cross‐polarization discrimination (XPD) are presented. Calculation of worst month statistics are also presen

ISSN:0737-2884    

DOI:10.1002/sat.4600070107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractIn a packet radio network that employs frequency‐hop transmission and error control coding, the use of side information permits identification and erasure of symbols that have been corrupted by multiple‐access interference, and thus greatly enhances multiple‐access capability. In one approach, side information is generated from an error detecting random code. We investigate the trade‐off between the reliability of side information and the rate of the code, and derive the maximum allowable code rate to achieve a certain reliability of side information. An achievable region and the channel throughput are examined for an unslotted frequency‐hop packet radio network that employs Reed‐Solomon codes and side information generated within the radio by an error det

ISSN:0737-2884    

DOI:10.1002/sat.4600070108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractA software production system for the generation of time slot assignment plans for SS/TDMA systems is proposed and implemented. The approach used in this system conveniently combines algorithms derived for ideal configurations with heuristic procedures that are needed to account for conditions present in real systems. Algorithms that produce plans with a minimum number of switchings and minimum traffic transmission duration can now be easily implemented. The assignment plans obtained are as efficient as those previously reported when the assumptions are the same. The proposed production system, however is capable of handling a much larger variety of constraints and heuristic procedures for which no efficient solutions have been reported.

ISSN:0737-2884    

DOI:10.1002/sat.4600070109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0737-2884    

DOI:10.1002/sat.4600070113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0737-2884    

DOI:10.1002/sat.4600070101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY