Pub Date : 1990-05-06DOI: 10.1109/VETEC.1990.110388
S. Tabbane, P. Godlewski
A reservation-Aloha-like (R-Aloha-like) protocol is studied in a decentralized mobile radio network context, with some hypotheses and assumptions and under specific constraints. Periodical traffic with parameter sharing and local communications are special characteristics of the model. The studied system faced problems, such as hidden nodes, fast changes in the network topology, and intervehicle communications. To solve or reduce some of these problems, the R-BTMA MAC protocol is introduced. It uses two distinct physical channels: a data channel and a busy-tone channel for signaling. Simulations are presented to evaluate the R-BTMA performance. The main service considered is parameter sharing with a regular traffic: one packet per frame and per vehicle. Numerical results show the improvements in channel throughput. The reaccess delay is evaluated.<>
{"title":"R-BTMA: a MAC protocol for short-range mobile radio communications","authors":"S. Tabbane, P. Godlewski","doi":"10.1109/VETEC.1990.110388","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110388","url":null,"abstract":"A reservation-Aloha-like (R-Aloha-like) protocol is studied in a decentralized mobile radio network context, with some hypotheses and assumptions and under specific constraints. Periodical traffic with parameter sharing and local communications are special characteristics of the model. The studied system faced problems, such as hidden nodes, fast changes in the network topology, and intervehicle communications. To solve or reduce some of these problems, the R-BTMA MAC protocol is introduced. It uses two distinct physical channels: a data channel and a busy-tone channel for signaling. Simulations are presented to evaluate the R-BTMA performance. The main service considered is parameter sharing with a regular traffic: one packet per frame and per vehicle. Numerical results show the improvements in channel throughput. The reaccess delay is evaluated.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117153415","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110373
R. Krishnamurthi, S.C. Gupta
A theoretical analysis of the error performance of a Gray encoded quadrature phase shift keying (QPSK) scheme in the presence of thermal Gaussian noise and a fading cochannel interference signal in a slow fading indoor wireless channel is presented. The exact error probability expression is presented in a closed form with the error manifesting the combined effect of noise and interference. The system model and the underlying assumptions are specified, and the problem is formulated. The expressions for the bit and symbol error rates are derived. The performance plots and conclusions are presented. It is shown that the exact bit error ratio and the symbol error can be expressed in a closed form.<>
{"title":"The error probability performance of Gray encoded QPSK scheme with co-channel interference in a slow fading indoor channel","authors":"R. Krishnamurthi, S.C. Gupta","doi":"10.1109/VETEC.1990.110373","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110373","url":null,"abstract":"A theoretical analysis of the error performance of a Gray encoded quadrature phase shift keying (QPSK) scheme in the presence of thermal Gaussian noise and a fading cochannel interference signal in a slow fading indoor wireless channel is presented. The exact error probability expression is presented in a closed form with the error manifesting the combined effect of noise and interference. The system model and the underlying assumptions are specified, and the problem is formulated. The expressions for the bit and symbol error rates are derived. The performance plots and conclusions are presented. It is shown that the exact bit error ratio and the symbol error can be expressed in a closed form.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125072439","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110367
S. Elnoubi, E. Fahmy, E.-s. El-badawy
The performance of trellis-coded quadrature phase shift keying (QPSK) in mobile radio communication channels characterized by fast Rayleigh fading is studied using Monte Carlo simulation. The receiver consists of one-bit and two-bit differential detectors followed by Viterbi decoding. This receiver improves the bit error rate of QPSK in additive white Gaussian noise channels. The simulation studies of this receiver to detect trellis-coded QPSK in fast Rayleigh fading are presented. The mobile radio channel simulator using a finite impulse response digital filter is described. Simulation results computed by Monte Carlo counting techniques are presented at different fading rates and signal-to-noise ratios.<>
{"title":"Performance of trellis coded QPSK in mobile radio channels","authors":"S. Elnoubi, E. Fahmy, E.-s. El-badawy","doi":"10.1109/VETEC.1990.110367","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110367","url":null,"abstract":"The performance of trellis-coded quadrature phase shift keying (QPSK) in mobile radio communication channels characterized by fast Rayleigh fading is studied using Monte Carlo simulation. The receiver consists of one-bit and two-bit differential detectors followed by Viterbi decoding. This receiver improves the bit error rate of QPSK in additive white Gaussian noise channels. The simulation studies of this receiver to detect trellis-coded QPSK in fast Rayleigh fading are presented. The mobile radio channel simulator using a finite impulse response digital filter is described. Simulation results computed by Monte Carlo counting techniques are presented at different fading rates and signal-to-noise ratios.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125552035","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110322
G. Stuber, L. Yiin
A model for predicting downlink outage due to cochannel interference in cellular radio systems is presented. The model accounts for path loss, shadowing, and Rayleigh fading. The effects of cell sectoring, power control, and hand-offs are discussed. Particular results are obtained for a cellular system that uses QDPSK with Reed-Solomon coding. Computation of the outage is described. Outage control techniques are discussed, and the impact of Reed-Solomon coding on spectral efficiency is evaluated.<>
{"title":"Outage predictions in digital cellular radio systems","authors":"G. Stuber, L. Yiin","doi":"10.1109/VETEC.1990.110322","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110322","url":null,"abstract":"A model for predicting downlink outage due to cochannel interference in cellular radio systems is presented. The model accounts for path loss, shadowing, and Rayleigh fading. The effects of cell sectoring, power control, and hand-offs are discussed. Particular results are obtained for a cellular system that uses QDPSK with Reed-Solomon coding. Computation of the outage is described. Outage control techniques are discussed, and the impact of Reed-Solomon coding on spectral efficiency is evaluated.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"1995 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125564392","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110415
D. Munoz-Rodriguez
A general paging problem formulation for mobile subscribers in cellular systems bearing in mind the number of paging signals and elapsed time is presented. Different search strategies are examined in an exponential traveling model. Expressions for mean number of paging signals and searching cost are obtained. Some emphasis is given to hexagonal cell clustering. It is shown that due to mobile traveling patterns, good performance, both in terms of cost and covering area, can be achieved with a small number of paging stages. It is also observed that for cell clustering, a travel model of the form P/sub i/=k alpha /sup i/ is in good agreement with empirical results, and can be used to assess mobile subscriber paging costs.<>
{"title":"Cluster paging for traveling subscribers","authors":"D. Munoz-Rodriguez","doi":"10.1109/VETEC.1990.110415","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110415","url":null,"abstract":"A general paging problem formulation for mobile subscribers in cellular systems bearing in mind the number of paging signals and elapsed time is presented. Different search strategies are examined in an exponential traveling model. Expressions for mean number of paging signals and searching cost are obtained. Some emphasis is given to hexagonal cell clustering. It is shown that due to mobile traveling patterns, good performance, both in terms of cost and covering area, can be achieved with a small number of paging stages. It is also observed that for cell clustering, a travel model of the form P/sub i/=k alpha /sup i/ is in good agreement with empirical results, and can be used to assess mobile subscriber paging costs.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116222530","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110292
M. Faulkner, T. Mattsson, W. Yates
One method of linearisation for class C RF power amplifiers is to pre-distort the drive signal. It is necessary to adjust the pre-distort waveform so that it can track changes in amplifier characteristics. An adaptive predistortion technique which uses a digital signal-processing microprocessor and memory look-up tables is described. The method differs from a previously described adaptive predistortion technique by using much smaller table sizes, with the result that conversion speeds are much higher. The disadvantage is that the processing overhead is higher, which puts a limit on the maximum data rate of the system. Low data rate services such as are found in mobile satellite applications (<17 kb/s) can be handled by this digital signal-processing approach. System requirements are examined, some alternative linearization techniques are described, and a more detailed analysis of adaptive predistortion is given. Finally a prototype system which uses digital signal-processing (DSP) techniques is described.<>
{"title":"Adaptive linearisation using pre-distortion","authors":"M. Faulkner, T. Mattsson, W. Yates","doi":"10.1109/VETEC.1990.110292","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110292","url":null,"abstract":"One method of linearisation for class C RF power amplifiers is to pre-distort the drive signal. It is necessary to adjust the pre-distort waveform so that it can track changes in amplifier characteristics. An adaptive predistortion technique which uses a digital signal-processing microprocessor and memory look-up tables is described. The method differs from a previously described adaptive predistortion technique by using much smaller table sizes, with the result that conversion speeds are much higher. The disadvantage is that the processing overhead is higher, which puts a limit on the maximum data rate of the system. Low data rate services such as are found in mobile satellite applications (<17 kb/s) can be handled by this digital signal-processing approach. System requirements are examined, some alternative linearization techniques are described, and a more detailed analysis of adaptive predistortion is given. Finally a prototype system which uses digital signal-processing (DSP) techniques is described.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122487299","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110304
J. Tiedeke, P. Schabel, E. Rille
The determination of relative distances and relative speeds between vehicles is a prerequisite for the implementation of features like collision avoidance or automatic guidance in vehicle control systems. An experimental optoelectronic system for this purpose that is based on a multisegment infrared laser emitter and receiver system using no moving parts is described. The multisegment distance measurement system for vehicle applications is a development tool both to optimize the sensor and to develop the signal processing for a multi or single-sensor system. First results are presented and future applications are described. The single and multiple-beam systems are able to measure distances from about 5 m up to 150 m with a dynamic accuracy of 0.1 up to 0.8 m. The measurement cycle time depends on the distance and amounts between 10 and 100 ms. The system has a double active safety system to obtain maximum distance performance at maximum eye safety.<>
{"title":"Vehicle distance sensor using a segmented IR laser beam","authors":"J. Tiedeke, P. Schabel, E. Rille","doi":"10.1109/VETEC.1990.110304","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110304","url":null,"abstract":"The determination of relative distances and relative speeds between vehicles is a prerequisite for the implementation of features like collision avoidance or automatic guidance in vehicle control systems. An experimental optoelectronic system for this purpose that is based on a multisegment infrared laser emitter and receiver system using no moving parts is described. The multisegment distance measurement system for vehicle applications is a development tool both to optimize the sensor and to develop the signal processing for a multi or single-sensor system. First results are presented and future applications are described. The single and multiple-beam systems are able to measure distances from about 5 m up to 150 m with a dynamic accuracy of 0.1 up to 0.8 m. The measurement cycle time depends on the distance and amounts between 10 and 100 ms. The system has a double active safety system to obtain maximum distance performance at maximum eye safety.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122015401","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110314
K. Kohiyama, T. Hattori, H. Sekiguchi, R. Kawasaki
A novel concept for personal communication that achieves the ultimate objectives of communications services, to enable anyone to communicate instantly with anyone anywhere, is proposed. This concept offers a personal service network with subscriber access systems for both wired and radio terminals. Its three principal concepts are: (1) assigning a personal identity such as a personal telecommunication number for individual, with the network tracking the person's routing, (2) serving ultra-small portable units for radio link access, and (3) servicing advanced functions such as the network playing the role of secretary. An advanced personal communication system in which such functions as location registration and tracking exchange are handled by public communications networks is proposed. Cost-effective and rapid service development can be realizing by using such public communication network facilities as transport systems. The proposed system enables each person to afford a portable telephone set because of large cost reductions and increased capacity, The system architecture and technical problems are also presented.<>
{"title":"Advanced personal communication system","authors":"K. Kohiyama, T. Hattori, H. Sekiguchi, R. Kawasaki","doi":"10.1109/VETEC.1990.110314","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110314","url":null,"abstract":"A novel concept for personal communication that achieves the ultimate objectives of communications services, to enable anyone to communicate instantly with anyone anywhere, is proposed. This concept offers a personal service network with subscriber access systems for both wired and radio terminals. Its three principal concepts are: (1) assigning a personal identity such as a personal telecommunication number for individual, with the network tracking the person's routing, (2) serving ultra-small portable units for radio link access, and (3) servicing advanced functions such as the network playing the role of secretary. An advanced personal communication system in which such functions as location registration and tracking exchange are handled by public communications networks is proposed. Cost-effective and rapid service development can be realizing by using such public communication network facilities as transport systems. The proposed system enables each person to afford a portable telephone set because of large cost reductions and increased capacity, The system architecture and technical problems are also presented.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"316 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128669448","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110363
S. Le-Ngoc
A high performance data communication system is designed using a 2.5 GHz radio with a data transmission rate of 6.312 Mbit/s and a 800 MHz radio with a data transmission rate of 4800 bit/s. To countermeasure both random bit and burst errors, Reed-Solomon (RS) codes are considered for the forward and reverse channels. The system reliability is improved by using an adaptive forward error correction (FEC) scheme in the forward channel and a conventional FEC scheme in the reverse channel. As a result, the stop-and-wait protocol is used to simplify the circuitry and avoid large buffers, and yet the system requirement can still be met. The proposed coding and retransmission strategy seems suitable for use in a severe multipath fading.<>
{"title":"Design of an adaptive coding and retransmission strategy for a multipath fading channel","authors":"S. Le-Ngoc","doi":"10.1109/VETEC.1990.110363","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110363","url":null,"abstract":"A high performance data communication system is designed using a 2.5 GHz radio with a data transmission rate of 6.312 Mbit/s and a 800 MHz radio with a data transmission rate of 4800 bit/s. To countermeasure both random bit and burst errors, Reed-Solomon (RS) codes are considered for the forward and reverse channels. The system reliability is improved by using an adaptive forward error correction (FEC) scheme in the forward channel and a conventional FEC scheme in the reverse channel. As a result, the stop-and-wait protocol is used to simplify the circuitry and avoid large buffers, and yet the system requirement can still be met. The proposed coding and retransmission strategy seems suitable for use in a severe multipath fading.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"72 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114102398","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 : 1990-05-06DOI: 10.1109/VETEC.1990.110335
S. Rappaport
A preliminary analytical model that characterizes the central issues of the hand-off problem when vehicles can support multiple calls simultaneously is described. In such cases a cell-boundary crossing by a single vehicle can generate multiple hand-off attempts. Theoretical performance characteristics that show blocking and hand-off failure probabilities as functions of communications traffic are determined. The results indicate that cut-off priority can be effective in reducing forced termination due to hand-off failure in an environment where platforms support multiple calls.<>
{"title":"The multiple-call hand-off problem in high-capacity cellular communications systems","authors":"S. Rappaport","doi":"10.1109/VETEC.1990.110335","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110335","url":null,"abstract":"A preliminary analytical model that characterizes the central issues of the hand-off problem when vehicles can support multiple calls simultaneously is described. In such cases a cell-boundary crossing by a single vehicle can generate multiple hand-off attempts. Theoretical performance characteristics that show blocking and hand-off failure probabilities as functions of communications traffic are determined. The results indicate that cut-off priority can be effective in reducing forced termination due to hand-off failure in an environment where platforms support multiple calls.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121676249","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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