Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258335
S. Dimolitsas, F. Corcoran
A technique for reducing the transmission requirements of facsimile images while maintaining high intelligibility in mobile communications environments is described. The algorithms developed are capable of achieving a compression of approximately 32 to 1. The technique focuses on the implementation of a low-cost interface unit suitable for facsimile communication between low-power mobile stations and fixed stations for both point-to-point and point-to-multipoint transmissions. This interface may be colocated with the transmitting facsimile terminals. The technique was implemented and tested by intercepting facsimile documents in a store-and-forward mode.<>
{"title":"Compression of facsimile graphics for transmission over digital mobile satellite circuits","authors":"S. Dimolitsas, F. Corcoran","doi":"10.1109/MILCOM.1991.258335","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258335","url":null,"abstract":"A technique for reducing the transmission requirements of facsimile images while maintaining high intelligibility in mobile communications environments is described. The algorithms developed are capable of achieving a compression of approximately 32 to 1. The technique focuses on the implementation of a low-cost interface unit suitable for facsimile communication between low-power mobile stations and fixed stations for both point-to-point and point-to-multipoint transmissions. This interface may be colocated with the transmitting facsimile terminals. The technique was implemented and tested by intercepting facsimile documents in a store-and-forward mode.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124883820","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258297
W. Ralston, J. Weitzen
It is shown that code division multiple access (CDMA) could be used to provide multiple access capability for large meteor burst communication networks. A single code with a high chip rate could be used for all stations, relying on differential range to provide orthogonality. By using suitable approximations, the performance of a direct sequence CDMA network is shown to eliminate collision problems and provide greater total throughput than an equivalent data rate narrowband network. Extensions to accommodate nonmeteoric propagation modes are outlined.<>
{"title":"Performance of meteor scatter networks using code division multiple access","authors":"W. Ralston, J. Weitzen","doi":"10.1109/MILCOM.1991.258297","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258297","url":null,"abstract":"It is shown that code division multiple access (CDMA) could be used to provide multiple access capability for large meteor burst communication networks. A single code with a high chip rate could be used for all stations, relying on differential range to provide orthogonality. By using suitable approximations, the performance of a direct sequence CDMA network is shown to eliminate collision problems and provide greater total throughput than an equivalent data rate narrowband network. Extensions to accommodate nonmeteoric propagation modes are outlined.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124127524","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258431
T. Gulliver
A technique recently devised for diversity combining is used to detect the presence of a burst of continuous wave (CW) synchronization probes in a fast frequency-hopped communication system. Often noise samples from unused channels are used to generate interference statistics to ensure a low false alarm rate. The presence of intelligent jamming can potentially increase this alarm rate to an unacceptable level and severely degrade performance. As an alternative, the author presents a method for detection which has been shown to provide robust data diversity combining under noise and multitone jamming without the use of channel state information. The approach is based on the second and first moments of the signal samples over L hops. An attempt is made to subtract the variations due to jamming using estimates of these moments. Results are given which show that this method provides superior performance to other diversity combining methods in worst-case noise and multitone jamming.<>
{"title":"A moment method for the detection of synchronization probes in worst case noise and multitone jamming","authors":"T. Gulliver","doi":"10.1109/MILCOM.1991.258431","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258431","url":null,"abstract":"A technique recently devised for diversity combining is used to detect the presence of a burst of continuous wave (CW) synchronization probes in a fast frequency-hopped communication system. Often noise samples from unused channels are used to generate interference statistics to ensure a low false alarm rate. The presence of intelligent jamming can potentially increase this alarm rate to an unacceptable level and severely degrade performance. As an alternative, the author presents a method for detection which has been shown to provide robust data diversity combining under noise and multitone jamming without the use of channel state information. The approach is based on the second and first moments of the signal samples over L hops. An attempt is made to subtract the variations due to jamming using estimates of these moments. Results are given which show that this method provides superior performance to other diversity combining methods in worst-case noise and multitone jamming.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130071167","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258476
B. Stein, W. Tsang
A coded modulation scheme is proposed to carry out the Global Navigation Satellite System (GLONASS) geostationary augmentation which includes both integrity and navigation functions over the next generation International Maritime Satellite Organization (INMARSAT) satellites. A baseline coded modulation scheme for the GLONASS augmentation broadcast proposes a forward error correction code over a differential phase shift keying (DPSK) modulation. The use of a concatenated code over the same signaling is considered. The proposed coded modulation design is more powerful and robust, yet not overly more complex in system implementation than the baseline scheme. Performance results of concatenated codes over a DPSK signaling used in the design are presented. The sensitivity analysis methodology in selecting the coded modulation scheme is also discussed.<>
{"title":"A coded modulation design for the INMARSAT geostationary GLONASS augmentation","authors":"B. Stein, W. Tsang","doi":"10.1109/MILCOM.1991.258476","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258476","url":null,"abstract":"A coded modulation scheme is proposed to carry out the Global Navigation Satellite System (GLONASS) geostationary augmentation which includes both integrity and navigation functions over the next generation International Maritime Satellite Organization (INMARSAT) satellites. A baseline coded modulation scheme for the GLONASS augmentation broadcast proposes a forward error correction code over a differential phase shift keying (DPSK) modulation. The use of a concatenated code over the same signaling is considered. The proposed coded modulation design is more powerful and robust, yet not overly more complex in system implementation than the baseline scheme. Performance results of concatenated codes over a DPSK signaling used in the design are presented. The sensitivity analysis methodology in selecting the coded modulation scheme is also discussed.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128050041","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258213
R. Cramer, M. Fitz
The authors present a statistical characterization of a uniformly sampled, first-order, decision-directed (DD), digitally implemented phase-locked loop (DPLL) for MPSK modulations. The phase detector (PD) considered has an ideal sawtooth form. A discrete-time Markov chain characterizes the DPLL and the associated PD. The signal, demodulator, and loop models are presented. The Markov chain describing the DD-DPLL operation is developed. Numerical considerations are discussed, and the steady-state phase error density functions are derived. These results are used to calculate the bit error probability for BPSK, QPSK, and 8PSK DPLL-based demodulators.<>
{"title":"The bit error probability performance for a digital PLL based MPSK demodulator","authors":"R. Cramer, M. Fitz","doi":"10.1109/MILCOM.1991.258213","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258213","url":null,"abstract":"The authors present a statistical characterization of a uniformly sampled, first-order, decision-directed (DD), digitally implemented phase-locked loop (DPLL) for MPSK modulations. The phase detector (PD) considered has an ideal sawtooth form. A discrete-time Markov chain characterizes the DPLL and the associated PD. The signal, demodulator, and loop models are presented. The Markov chain describing the DD-DPLL operation is developed. Numerical considerations are discussed, and the steady-state phase error density functions are derived. These results are used to calculate the bit error probability for BPSK, QPSK, and 8PSK DPLL-based demodulators.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129653157","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258441
J. Luecke, H. Truong
An integrated receiver (IR) designed to support multiple access, S-band single access (SSA), K-band single access (KSA), S-band Shuttle return (SSHR), and K-band Shuttle return (KSHR) services for the second Tracking Data and Relay Satellite System (TDRSS) ground terminal (STGT) is being developed. With a VLSI/ASIC-intensive design, the IR integrates the demodulator, symbol synchronizer, pseudonoise (PN) tracking, carrier recovery, and data recovery functions into a single integrated unit. The authors describe the overall receiver design and implementation, with particular emphasis on the demodulation and tracking loop operation. Laboratory measurements are presented that demonstrate the bit error rate performance capability of the receiver.<>
{"title":"Design and performance of the integrated receiver for NASA's second TDRSS ground terminal","authors":"J. Luecke, H. Truong","doi":"10.1109/MILCOM.1991.258441","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258441","url":null,"abstract":"An integrated receiver (IR) designed to support multiple access, S-band single access (SSA), K-band single access (KSA), S-band Shuttle return (SSHR), and K-band Shuttle return (KSHR) services for the second Tracking Data and Relay Satellite System (TDRSS) ground terminal (STGT) is being developed. With a VLSI/ASIC-intensive design, the IR integrates the demodulator, symbol synchronizer, pseudonoise (PN) tracking, carrier recovery, and data recovery functions into a single integrated unit. The authors describe the overall receiver design and implementation, with particular emphasis on the demodulation and tracking loop operation. Laboratory measurements are presented that demonstrate the bit error rate performance capability of the receiver.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126484024","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258228
D. Olsen, N. Dave
Dynamically reserved slot management (DRSM) is a dynamic, distributed slot management protocol for time-division-multiple-access (TDMA)-based packet radio networks, residing at the network layer of the International Standards Organization (ISO) open systems interconnect (OSI) reference model. The authors discuss the functions and implementation of the DRSM protocol and present some simulation results. DRSM supports multiple ownership of a single TDMA slot, resulting in increased effective bandwidth and throughput. In DRSM, any slot not currently owned by another node within a two-hop connectivity radius is available to be reserved, should it be needed. A key feature of DRSM is that a slot change is made in advance (reserved) during a slot already owned (such as a TDMA slot). Thus, most slot contentions are resolved as reservation contentions, which requires the concurrence of one's neighbors before using a shared slot, rather than transmission contention and collision.<>
{"title":"Dynamically reserved slot management (DRSM) for packet radio networks","authors":"D. Olsen, N. Dave","doi":"10.1109/MILCOM.1991.258228","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258228","url":null,"abstract":"Dynamically reserved slot management (DRSM) is a dynamic, distributed slot management protocol for time-division-multiple-access (TDMA)-based packet radio networks, residing at the network layer of the International Standards Organization (ISO) open systems interconnect (OSI) reference model. The authors discuss the functions and implementation of the DRSM protocol and present some simulation results. DRSM supports multiple ownership of a single TDMA slot, resulting in increased effective bandwidth and throughput. In DRSM, any slot not currently owned by another node within a two-hop connectivity radius is available to be reserved, should it be needed. A key feature of DRSM is that a slot change is made in advance (reserved) during a slot already owned (such as a TDMA slot). Thus, most slot contentions are resolved as reservation contentions, which requires the concurrence of one's neighbors before using a shared slot, rather than transmission contention and collision.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121047685","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258434
S. Pan, H. Grant, D. Dodds, S. Kumar
A novel Z search method is proposed in which the search is started at a position in the code phase uncertainty region which is offset from center. Using the unified time-domain approach developed by A. Polydoros and C. L. Weber (1984) the distribution and mean of the acquisition time have been obtained for the offset Z search strategy. Based on the mean acquisition time, the optimum offset of the Z search has been studied. The proposed method can improve mean acquisition by as much as 30% when compared with the best previous Z search strategy. The search pattern is optimized by a simple adjustment of the offset parameter.<>
提出了一种新的从码相位不确定区域中偏离中心的位置开始搜索的Z搜索方法。利用A. Polydoros和C. L. Weber(1984)开发的统一时域方法，获得了偏移Z搜索策略的采集时间分布和平均值。基于平均捕获时间，研究了Z搜索的最优偏移量。与以前最好的Z搜索策略相比，所提出的方法可以将平均获取率提高30%。搜索模式通过对offset参数的简单调整来优化。
{"title":"An offset Z search strategy for spread spectrum systems","authors":"S. Pan, H. Grant, D. Dodds, S. Kumar","doi":"10.1109/MILCOM.1991.258434","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258434","url":null,"abstract":"A novel Z search method is proposed in which the search is started at a position in the code phase uncertainty region which is offset from center. Using the unified time-domain approach developed by A. Polydoros and C. L. Weber (1984) the distribution and mean of the acquisition time have been obtained for the offset Z search strategy. Based on the mean acquisition time, the optimum offset of the Z search has been studied. The proposed method can improve mean acquisition by as much as 30% when compared with the best previous Z search strategy. The search pattern is optimized by a simple adjustment of the offset parameter.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123232939","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258289
Y. Wong, J. Rash
A method to mitigate interference while minimizing unnecessary scheduling restrictions on the NASA tracking and data relay satellite system (TDRSS) network and user resources, based on consideration of all relevant communications parameters, has been developed. This method also can be used as the basis for analysis, evaluation, and optimization of user schedules with respect to communications performance. The method and its proposed application to scheduling in space communications are described. Test cases relative to planned missions, including the Earth Observing System, the Space Station manned base, and the Space Shuttle are discussed.<>
{"title":"A method for interference mitigation in space communications scheduling","authors":"Y. Wong, J. Rash","doi":"10.1109/MILCOM.1991.258289","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258289","url":null,"abstract":"A method to mitigate interference while minimizing unnecessary scheduling restrictions on the NASA tracking and data relay satellite system (TDRSS) network and user resources, based on consideration of all relevant communications parameters, has been developed. This method also can be used as the basis for analysis, evaluation, and optimization of user schedules with respect to communications performance. The method and its proposed application to scheduling in space communications are described. Test cases relative to planned missions, including the Earth Observing System, the Space Station manned base, and the Space Shuttle are discussed.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123416518","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}
Pub Date : 1991-11-04DOI: 10.1109/MILCOM.1991.258261
S. H. George
The author uses universal personal telecommunications (UPT) as an example of how the Department of Defense (DoD) is communicating its needs to commercial standard bodies. The traditional approach to buying commercial off-the-shelf (COTS) products is to wait for industry to develop commercial standards for UPT and then for industry to offer UPT products. Rather than wait and buy only a limited number of suitable COTS UPT products that result from the tail-end of the traditional approach, DoD recognized that it would be more logical to influence the front-end of the process, that is, the development of commercial standards from which industry builds its UPT products. The Joint Telecommunications Standards Steering Group, which consists of representatives from the Joint Staff, the military services, and the defense agencies, is the DoD focal point for telecommunications.<>
{"title":"Projecting military needs into commercial standards","authors":"S. H. George","doi":"10.1109/MILCOM.1991.258261","DOIUrl":"https://doi.org/10.1109/MILCOM.1991.258261","url":null,"abstract":"The author uses universal personal telecommunications (UPT) as an example of how the Department of Defense (DoD) is communicating its needs to commercial standard bodies. The traditional approach to buying commercial off-the-shelf (COTS) products is to wait for industry to develop commercial standards for UPT and then for industry to offer UPT products. Rather than wait and buy only a limited number of suitable COTS UPT products that result from the tail-end of the traditional approach, DoD recognized that it would be more logical to influence the front-end of the process, that is, the development of commercial standards from which industry builds its UPT products. The Joint Telecommunications Standards Steering Group, which consists of representatives from the Joint Staff, the military services, and the defense agencies, is the DoD focal point for telecommunications.<<ETX>>","PeriodicalId":212388,"journal":{"name":"MILCOM 91 - Conference record","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124257572","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}
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