Pub Date : 1990-05-06DOI: 10.1109/VETEC.1990.110407
R. Barts, J. Kim, R. E. Porter, T. Pratt, W. Stutzman, C. Bostian
A simulator for mobile satellite system (MSS) link simulation is described. The simulation consists of two elements which evolved separately. The propagation simulator is used to produce fade data and statistics under a variety of path conditions. The channel simulator produces bit error rates (BER), under real propagation conditions, for several coding/modulation formats. The propagation simulator shows good agreement with theoretical fading models and experimental data. The channel simulator predicts bit error ratio (BER) very close to theoretical values for back-to-back modem tests, verifying its operation. When used with either experimental propagation data or simulated data from the propagation simulator, the channel simulator can predict channel performance under realistic fading conditions.<>
{"title":"Mobile satellite system performance through simulation","authors":"R. Barts, J. Kim, R. E. Porter, T. Pratt, W. Stutzman, C. Bostian","doi":"10.1109/VETEC.1990.110407","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110407","url":null,"abstract":"A simulator for mobile satellite system (MSS) link simulation is described. The simulation consists of two elements which evolved separately. The propagation simulator is used to produce fade data and statistics under a variety of path conditions. The channel simulator produces bit error rates (BER), under real propagation conditions, for several coding/modulation formats. The propagation simulator shows good agreement with theoretical fading models and experimental data. The channel simulator predicts bit error ratio (BER) very close to theoretical values for back-to-back modem tests, verifying its operation. When used with either experimental propagation data or simulated data from the propagation simulator, the channel simulator can predict channel performance under realistic fading conditions.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"27 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":"132184813","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.1990.110385
K. Murakami, K. Ueda, M. Takano, T. Fujino
The development of an adaptive equalizer for mobile radio using the Kalman algorithm is addressed, including an assessment of its performance by means of computer simulation and hardware experimentation. The adaptive equalizer consists of a fractionally spaced decision feedback equalizing element and a tap-coefficient-update element. Tap coefficients are updated based on the Kalman filter algorithm. Details for the parameters are given, such as the number of taps, the quantization number of bits, and the forgetting factor. Hardware of the equalizer consists of a digital signal processor and a few finite impulse response digital filters implemented on some LSI chips where the tap coefficients are adaptively changeable. A bit error ratio (BER) of less than 10/sup -2/ is achieved, and remarkable improvement is observed compared with the unequalized performance. It is shown that the adaptive equalizer is useful for fading multipath channels.<>
{"title":"Design of an adaptive Kalman equalizer and its performance over fading multipath channels","authors":"K. Murakami, K. Ueda, M. Takano, T. Fujino","doi":"10.1109/VETEC.1990.110385","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110385","url":null,"abstract":"The development of an adaptive equalizer for mobile radio using the Kalman algorithm is addressed, including an assessment of its performance by means of computer simulation and hardware experimentation. The adaptive equalizer consists of a fractionally spaced decision feedback equalizing element and a tap-coefficient-update element. Tap coefficients are updated based on the Kalman filter algorithm. Details for the parameters are given, such as the number of taps, the quantization number of bits, and the forgetting factor. Hardware of the equalizer consists of a digital signal processor and a few finite impulse response digital filters implemented on some LSI chips where the tap coefficients are adaptively changeable. A bit error ratio (BER) of less than 10/sup -2/ is achieved, and remarkable improvement is observed compared with the unequalized performance. It is shown that the adaptive equalizer is useful for fading multipath channels.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"122 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":"134619331","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.1990.110404
M. El-Tanany, S. Mahmoud
A novel approach to the design of quaternary continuous phase modulation (CPM) modems, with discriminator detection, is presented. This approach is comparable in complexity to binary modems. The proposed detector yields several dB of signal-to-noise ratio (SNR) savings when compared to the conventional symbol-by-symbol data detector. The numerical results also indicate the superiority of the proposed scheme over binary CPM modems for the same data rate and same bandwidth occupancy. These advantages, however, come at the expense of higher sensitivity to timing errors. Several practical techniques for timing recovery have been tried in the study, and seem to give the desired accuracies.<>
{"title":"Performance of a novel discriminator based quaternary CPM receiver","authors":"M. El-Tanany, S. Mahmoud","doi":"10.1109/VETEC.1990.110404","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110404","url":null,"abstract":"A novel approach to the design of quaternary continuous phase modulation (CPM) modems, with discriminator detection, is presented. This approach is comparable in complexity to binary modems. The proposed detector yields several dB of signal-to-noise ratio (SNR) savings when compared to the conventional symbol-by-symbol data detector. The numerical results also indicate the superiority of the proposed scheme over binary CPM modems for the same data rate and same bandwidth occupancy. These advantages, however, come at the expense of higher sensitivity to timing errors. Several practical techniques for timing recovery have been tried in the study, and seem to give the desired accuracies.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"48 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":"129739615","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.1990.110414
G. Ratzer, A. Mignot, P. Robertson
A system using a novel integrated package called SYMBL is described. The SYMBL package comprises the Longley-Rice model for computing radio wave propagation over a detailed topographical area. A radio transmission simulation system that uses SYMBL is described. The total system combines the SYMBL software, an interactive display package, a government-supplied database of topographical information, and an associated workstation, which provides high-resolution color graphics. One of the outputs features an automated topographic database verification with two- and three-dimensional views. The total system calculates the radio wave propagation receiver points at a rate exceeding 100 points/s, with an desired density and over any desired area coverage. The optimization of SYMBL and its adaptation to modern hardware and software, and how a user-friendly, multiple-window interface has created an environment specially tailored for a communications engineer to study current and planned telecommunication facilities are discussed.<>
{"title":"Radio transmission simulation using a high performance graphics workstation","authors":"G. Ratzer, A. Mignot, P. Robertson","doi":"10.1109/VETEC.1990.110414","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110414","url":null,"abstract":"A system using a novel integrated package called SYMBL is described. The SYMBL package comprises the Longley-Rice model for computing radio wave propagation over a detailed topographical area. A radio transmission simulation system that uses SYMBL is described. The total system combines the SYMBL software, an interactive display package, a government-supplied database of topographical information, and an associated workstation, which provides high-resolution color graphics. One of the outputs features an automated topographic database verification with two- and three-dimensional views. The total system calculates the radio wave propagation receiver points at a rate exceeding 100 points/s, with an desired density and over any desired area coverage. The optimization of SYMBL and its adaptation to modern hardware and software, and how a user-friendly, multiple-window interface has created an environment specially tailored for a communications engineer to study current and planned telecommunication facilities are discussed.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"76 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":"133983658","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.1990.110319
H. Chan, C. Vinodrai
Issues, such as how digital will co-exist with analog and the different strategies that can be adopted for introducing digital cellular, are examined. The driving forces of the upcoming technology and the impact it will have on the existing networks are studied. The alternatives available to convert cellular systems from analog to digital are evaluated. Introducing digital cellular on top of the current analog system presents many challenging problems, such as high subscriber terminal cost, rapidly diminishing analog capacity, and uncertain digital penetration. There are many solutions in various architectures which will address some of the problems. There are different paths for the transition to digital, with different costs, deployment speeds, and spectrum efficiencies. The selection of the transition path will depend on the strategy chosen by each individual service provider.<>
{"title":"The transition to digital cellular","authors":"H. Chan, C. Vinodrai","doi":"10.1109/VETEC.1990.110319","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110319","url":null,"abstract":"Issues, such as how digital will co-exist with analog and the different strategies that can be adopted for introducing digital cellular, are examined. The driving forces of the upcoming technology and the impact it will have on the existing networks are studied. The alternatives available to convert cellular systems from analog to digital are evaluated. Introducing digital cellular on top of the current analog system presents many challenging problems, such as high subscriber terminal cost, rapidly diminishing analog capacity, and uncertain digital penetration. There are many solutions in various architectures which will address some of the problems. There are different paths for the transition to digital, with different costs, deployment speeds, and spectrum efficiencies. The selection of the transition path will depend on the strategy chosen by each individual service provider.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"35 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":"116055044","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.1990.110351
D. M. Larsen, P.L. Notestine
The development and evolution of a versatile radio propagation and performance modeling system known as MSRFM (multisite RF model) is described. The modeling system consists of four major functional classifications: (a) the propagation model (MSRFM), (b) database utilities, (c) analysis programs, and (d) a plotting program (MSPLOT). Database and device support utilities are used initially to digitize and process terrain and clutter data. Output from MSRFM is in the form of predicted signal level. The accuracy and usefulness of MSRFM has been field-proven through its' use in the design of a large number of cellular systems in North, South, and Central America and numerous countries throughout the eastern hemisphere. Data taken from field measurements made in a wide variety of environments (ranging from jungle to urban and open areas) have been used in an on-going manner to further improve the accuracy of the calculation methods.<>
{"title":"MSRFM-a prediction tool for radio system design","authors":"D. M. Larsen, P.L. Notestine","doi":"10.1109/VETEC.1990.110351","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110351","url":null,"abstract":"The development and evolution of a versatile radio propagation and performance modeling system known as MSRFM (multisite RF model) is described. The modeling system consists of four major functional classifications: (a) the propagation model (MSRFM), (b) database utilities, (c) analysis programs, and (d) a plotting program (MSPLOT). Database and device support utilities are used initially to digitize and process terrain and clutter data. Output from MSRFM is in the form of predicted signal level. The accuracy and usefulness of MSRFM has been field-proven through its' use in the design of a large number of cellular systems in North, South, and Central America and numerous countries throughout the eastern hemisphere. Data taken from field measurements made in a wide variety of environments (ranging from jungle to urban and open areas) have been used in an on-going manner to further improve the accuracy of the calculation methods.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"114 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121002007","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.1990.110340
G.J. Freij, P. Mabey, A. Richardson, G. Cayla
Future evolution of private mobile radio systems in Europe is discussed, and a strategy for second-generation trunking based on the traditional strengths of dispatcher-type operation together with extensive provision of data and text services is proposed. Options for the radio interference, operating time-division multiple access (TDMA) are suggested as possible candidates for future trunking. Backed by the European Commission, the ETSI Technical Sub-Committee RES 6 is now coordinating the development of a digital pan-European trunking standard with the aim of making specifications available in 1994. The activities of ETSI-RES 6 are outlined, and criteria governing the development of a digital trunking standard are advanced. Suggestions for future services to be provided are then made, and possible scenarios for the physical layer are briefly discussed.<>
{"title":"Trunked mobile radio: towards a pan-European digital standard","authors":"G.J. Freij, P. Mabey, A. Richardson, G. Cayla","doi":"10.1109/VETEC.1990.110340","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110340","url":null,"abstract":"Future evolution of private mobile radio systems in Europe is discussed, and a strategy for second-generation trunking based on the traditional strengths of dispatcher-type operation together with extensive provision of data and text services is proposed. Options for the radio interference, operating time-division multiple access (TDMA) are suggested as possible candidates for future trunking. Backed by the European Commission, the ETSI Technical Sub-Committee RES 6 is now coordinating the development of a digital pan-European trunking standard with the aim of making specifications available in 1994. The activities of ETSI-RES 6 are outlined, and criteria governing the development of a digital trunking standard are advanced. Suggestions for future services to be provided are then made, and possible scenarios for the physical layer are briefly discussed.<<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":"125130110","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.1990.110361
R. Young, J. Lodge
A receiver structure, called linear-prediction-aided differential detection (LPADD), for detection of continuous phase modulation (CPM) signals with Nyquist III pulse shaping in fast Rayleigh flat-fading channels is presented. This technique was found to be capable of significantly reducing the bit error rate of conventional differential detection (CDD) at high signal-to-noise ratios. The algorithm reduces the phase noise power from the fading process at the differential detector. Therefore, performance benefits are only seen when the phase noise becomes the dominant source of degradation. Simulations showed that with practical predictor lengths the error floor of conventional differential detection can be reduced by more than a factor of 30.<>
{"title":"Linear-prediction-aided differential detection of CPM signals transmitted over Rayleigh flat fading channels","authors":"R. Young, J. Lodge","doi":"10.1109/VETEC.1990.110361","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110361","url":null,"abstract":"A receiver structure, called linear-prediction-aided differential detection (LPADD), for detection of continuous phase modulation (CPM) signals with Nyquist III pulse shaping in fast Rayleigh flat-fading channels is presented. This technique was found to be capable of significantly reducing the bit error rate of conventional differential detection (CDD) at high signal-to-noise ratios. The algorithm reduces the phase noise power from the fading process at the differential detector. Therefore, performance benefits are only seen when the phase noise becomes the dominant source of degradation. Simulations showed that with practical predictor lengths the error floor of conventional differential detection can be reduced by more than a factor of 30.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"2009 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":"125652679","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.1990.110405
S.H. Goode, H. L. Kazecki, D.W. Dennis
A brief description is given of limiter-discriminator, delay, and coherent detection of pi /4 quadrature phase shift keying (QPSK). Simulated bit error rate (BER) performance of these detectors in static and Rayleigh faded fields is presented. Performance in delay spread faded fields is also given. Results of the use of an equalizer with the coherent detector in delay spread faded fields is evaluated. Three methods of detecting pi /4 QPSK are evaluated. A brief description of the operation and an estimate of implementation complexity is given for each detector. Simulated results of BER performance for each detector in static, Rayleigh, and delays spread faded fields are then presented. The use of an adaptive decision feedback equalizer with a coherent detector is then evaluated for use in delay spread faded fields.<>
{"title":"A comparison of a limiter-discriminator, delay and coherent detection for pi /4 QPSK","authors":"S.H. Goode, H. L. Kazecki, D.W. Dennis","doi":"10.1109/VETEC.1990.110405","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110405","url":null,"abstract":"A brief description is given of limiter-discriminator, delay, and coherent detection of pi /4 quadrature phase shift keying (QPSK). Simulated bit error rate (BER) performance of these detectors in static and Rayleigh faded fields is presented. Performance in delay spread faded fields is also given. Results of the use of an equalizer with the coherent detector in delay spread faded fields is evaluated. Three methods of detecting pi /4 QPSK are evaluated. A brief description of the operation and an estimate of implementation complexity is given for each detector. Simulated results of BER performance for each detector in static, Rayleigh, and delays spread faded fields are then presented. The use of an adaptive decision feedback equalizer with a coherent detector is then evaluated for use in delay spread faded fields.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"26 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":"127962032","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.1990.110311
Y. Shimazaki, S. Ono, T. Nakai, N. Kondoh
A time-division multiple access (TDMA) cellular system using QPSK (quadrature phase shift keying) with coherent detection is studied. The required guard time between TDMA bursts and the effect of the unbalanced characteristics of an IF filter on a detected signal are analyzed. An attempt is made to minimize the guard time between TDMA burst signals using a window which suppresses the signal at both edges. As a result, it was found that the required guard time can be reduced to a 2.3 symbol duration in a 3-km radius cell. If a conventional IF filter (which is designed for an analog terminal) is adapted to a digital terminal, in cases of 1 kHz variation of the center frequency intersymbol interference caused by the IF filter would be about -20 dB. It is concluded that more sophisticated IF filters are needed for digital cellular terminals are needed than for analog cellular terminals.<>
{"title":"A design consideration on TDMA cellular radio","authors":"Y. Shimazaki, S. Ono, T. Nakai, N. Kondoh","doi":"10.1109/VETEC.1990.110311","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110311","url":null,"abstract":"A time-division multiple access (TDMA) cellular system using QPSK (quadrature phase shift keying) with coherent detection is studied. The required guard time between TDMA bursts and the effect of the unbalanced characteristics of an IF filter on a detected signal are analyzed. An attempt is made to minimize the guard time between TDMA burst signals using a window which suppresses the signal at both edges. As a result, it was found that the required guard time can be reduced to a 2.3 symbol duration in a 3-km radius cell. If a conventional IF filter (which is designed for an analog terminal) is adapted to a digital terminal, in cases of 1 kHz variation of the center frequency intersymbol interference caused by the IF filter would be about -20 dB. It is concluded that more sophisticated IF filters are needed for digital cellular terminals are needed than for analog cellular terminals.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"44 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":"132776751","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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