军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13516
S. An, W. Lindsey
{"title":"Satellite communication system performance in the presence of scintillation","authors":"S. An, W. Lindsey","doi":"10.1109/MILCOM.1988.13516","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13516","url":null,"abstract":"The authors demonstrate an approach to evaluating the bit-error probability performance of a satellite communication system operating in the presence of scintillation and thermal noise. The probability distribution function of the decision variable is used in an analytical simulation to predict bit-error probabilities for various channel conditions. With regard to treating the problems due to channel memory, a software simulator of the system has been developed; this simulator accounts for the coding, modulation, channel memory, noise, scintillation statistics, and the interleaver-deinterleaver system design. A tradeoff analysis is made with regard to different approaches concerning signal processing in the satellite and ground station. Soft- vs. hard-decision Viterbi decoding in a ground receiver is evaluated. Results on signal processing in the satellite as compared to that in the ground station are provided.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85753794","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13358
M. Pugh
{"title":"High speed fiber optic link design considerations","authors":"M. Pugh","doi":"10.1109/MILCOM.1988.13358","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13358","url":null,"abstract":"The design of high-speed optical data links involves a number of factors on which engineering tradeoffs must be made. The author discusses these tradeoffs as applied to modular computer communication links. It is concluded that it is possible to make a very cost-effective, ultrahigh-speed link by utilizing commercial technology. Low-cost 800-nm lasers allow data links operating in the 500-MHz range to be built with high optical power, permitting the use of less expensive multimode fiber, and lower gain receivers.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82673471","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13515
J. Hauser, D. Baker, D. McGregor, W. Thoet, P. Springston
{"title":"Prototyping communication system software with the Distributed Simulation and Prototyping Testbed","authors":"J. Hauser, D. Baker, D. McGregor, W. Thoet, P. Springston","doi":"10.1109/MILCOM.1988.13515","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13515","url":null,"abstract":"The authors describe the Distributed Simulation and Prototyping Testbed (DSPT) and show how it is used to develop prototype software. The ability to prototype software offers significant advantages to the successful development of C/sup 3/ systems, which are typically distributed, complex, and hard to test. The DSPT itself is a distributed system. However, its distributed nature is transparent to the user since interprocess communication and synchronization are handled automatically. The DSPT also provides detailed models of physical layer objects, platforms, transmitters, receivers, etc., via a well-defined interface. This interface provides the context for developing models of higher layer protocols. The use of DSPT tools to develop prototype software for the US Navy's Unified Network Technology is considered.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77568976","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13372
G. J. Luhowy
{"title":"Advances in HF parallel tone modem technology","authors":"G. J. Luhowy","doi":"10.1109/MILCOM.1988.13372","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13372","url":null,"abstract":"The author describes the HF modem, which contains a 75 to 2400 bps 39-tone waveform, a robust 75-bps direct-spread waveform, and two independent 45-1200-bps binary frequency-shift-keyed (FSK) waveforms. The availability of powerful new microprocessors permits economic implementation of complex signal-processing sizes. Improved signaling techniques and potent error-correcting codes allow greatly improved performance on the HF channel. Measured performance data taken on HF fading simulators and in numerous on-the-air tests are presented. The performance with and without diversity reception is also shown. An implementation that demonstrates the dramatic reduction in modem size, weight, power consumption, and cost realized by embedding the modem in modern digital radios such as the RF-5000 is presented.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91478870","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13374
P. A. Bello
{"title":"Performance of some Rake modems over the non-disturbed wide band HF channel","authors":"P. A. Bello","doi":"10.1109/MILCOM.1988.13374","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13374","url":null,"abstract":"The author presents performance evaluations for four Rake modems used to communicate over the wideband (e.g. 1 MHz) HF channel. Attention is confined to performance for the nondisturbed HF channel. Consideration is given to the impact of mode Doppler shift and multipath spread due to dispersion. The effects of additive noise, self-noise, and imperfect channel measurements are included. Results are presented for decision-directed, parallel probe, serial probe, and DPSK Rake modems. Performance to within 1-3 dB of the additive white Gaussian noise channel is predicted, depending upon the modem and the channel dispersion, if the Doppler shift of the modem can be tracked to within 0.1 Hz.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90507256","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13395
B. Schnitta‐Israel, L. Rosenblum
{"title":"EMUL-a parallel processor emulator","authors":"B. Schnitta‐Israel, L. Rosenblum","doi":"10.1109/MILCOM.1988.13395","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13395","url":null,"abstract":"EMUL is a user-friendly computer program that emulates the operation of a parallel processor. EMUL's capacity to emulate down to the chip or up to the cell level of a parallel processor gives EMUL powerful applications. Its capability to specify a parallel processor down to the chip/noise level, without regard for low-level electronic details such as drivers and resistors, permits the user to research extensively the development of a cell within any parallel processor design. This allows the user to develop a better understanding of the innate behavior of a parallel processor. Also, since each chip has complete specification freedom, EMUL encourages examination of numerical performance, quantization effects, data dependency, and error analysis. Finally, the ability of EMUL to specify a parallel processor up to the cell level furnishes the user with a convenient tool to verify actual chip and cell operations once the design layout is realized in hardware. A length three direct-form finite-impulse response filter is considered as an application example.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90759327","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13465
P. Feldman
{"title":"Effect of interference on throughput of adaptive hybrid ARQ protocol","authors":"P. Feldman","doi":"10.1109/MILCOM.1988.13465","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13465","url":null,"abstract":"The author analyzes the effect of unanticipated CW and pulsed interference on the throughput of an adaptive hybrid ARQ protocol used with a discrete-time Markovian channel. He evaluates the degradation in the performance of this protocol due to additional, unanticipated interference and shows that the protocol is only slightly suboptimal under these conditions, i.e. only a small part of the degradation can be attributed to the protocol's reliance on incorrect channel statistics. He also shows that the performance of the adaptive protocol is at least as good as that of a simpler nonadaptive protocol over almost the entire range of jammer power levels.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89380272","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13401
P. Crane
{"title":"An empirical analysis of the application of forward error correction to meteor burst communication","authors":"P. Crane","doi":"10.1109/MILCOM.1988.13401","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13401","url":null,"abstract":"Presents the results of an analysis of data gathered during a meteor burst experiment in Greenland. Bit error patterns are obtained and the performance of automatic request for retransmission and forward error correction (FEC) are compared from the standpoint of throughput and encountered delays with respect to the delivery of a 40-character message. It is demonstrated that throughput can be increased and delays decreased with respect to the delivery of short messages over a meteor burst communications channel by the use of simple FEC techniques. The addition of a low degree interleaver provides additional substantial improvement.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87787263","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13521
R. Merk, L. Gutman, C. Warner
{"title":"Voice and data integration in tactical networks","authors":"R. Merk, L. Gutman, C. Warner","doi":"10.1109/MILCOM.1988.13521","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13521","url":null,"abstract":"The authors propose algorithms for supporting voice and data in a tactical ultrahigh-frequency line-of-sight (UHF LOS) network for communications within a Navy task force. The UHF LOS network is being developed by the Navy's Unified Networking Technology (UNT) program. It has properties in common with most tactical networks, and thus the algorithms presented here should be applicable to these networks in general. They have been designed to accommodate the limited bandwidth typical of tactical networks which makes integration of voice and data difficult. Also, the algorithms are robust, efficient, and survivable. The following features are considered: voice and data requirements, broadcast routing, point-to-point routing, channel access, voice algorithms, voice implementation, and channel release.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87790445","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}
军事通信技术Pub Date : 1988-10-23DOI: 10.1109/MILCOM.1988.13421
Jeffrey H. Reed, A. A. Quilici, T. Hsia
{"title":"A frequency domain time-dependent adaptive filter for interference rejection","authors":"Jeffrey H. Reed, A. A. Quilici, T. Hsia","doi":"10.1109/MILCOM.1988.13421","DOIUrl":"https://doi.org/10.1109/MILCOM.1988.13421","url":null,"abstract":"The authors examine a type of adaptive filter called a time-dependent adaptive filter (TDAF). A TDAF can effectively deal with the cyclostationary nature of communication signals by changing periodically. It achieves a smaller mean-square error than conventional filter for cyclostationary signals. A frequency-domain TDAF is investigated, and it is shown that it is especially effective for interference rejection applications. Simulation results are presented, showing how cochannel QPSK signals can be separated.<<ETX>>","PeriodicalId":66166,"journal":{"name":"军事通信技术","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1988-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84021108","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}