Pub Date : 1990-05-06DOI: 10.1109/VETEC.1990.110344
G. Mony, B. Toplis, J. Michaelides
The structure and performance of a circuit-switched data transport mechanism that transmits up to 9.6 kb/s asynchronous data over a North American time-division multiple access (TDMA) digital cellular radio channel are described. Options for the radio data link layer protocol are examined. The ARQ protocols examined are derived from the high-level data link control (HDLC) family. The options considered are type-one hybrid ARQ (automatic repeat request) schemes using a HDLC data link layer and Reed-Solomon forward error correction. Asynchronous throughput results obtained using a Rayleigh fading model are presented for different speeds and carrier-to-interference ratios. Simulations indicate that at least 4.8 kb/s throughput is achievable for a 17 dB carrier-to-interference ratio, and performance rapidly approaches the maximum rate of 9.6 kb/s for less interference.<>
{"title":"Performance assessment of data transport alternatives for digital cellular radio","authors":"G. Mony, B. Toplis, J. Michaelides","doi":"10.1109/VETEC.1990.110344","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110344","url":null,"abstract":"The structure and performance of a circuit-switched data transport mechanism that transmits up to 9.6 kb/s asynchronous data over a North American time-division multiple access (TDMA) digital cellular radio channel are described. Options for the radio data link layer protocol are examined. The ARQ protocols examined are derived from the high-level data link control (HDLC) family. The options considered are type-one hybrid ARQ (automatic repeat request) schemes using a HDLC data link layer and Reed-Solomon forward error correction. Asynchronous throughput results obtained using a Rayleigh fading model are presented for different speeds and carrier-to-interference ratios. Simulations indicate that at least 4.8 kb/s throughput is achievable for a 17 dB carrier-to-interference ratio, and performance rapidly approaches the maximum rate of 9.6 kb/s for less interference.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"41 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":"126511145","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.1990.110355
T. Takeuchi, M. Sako, S. Yoshida
Multipath delay profile measurements were conducted in a meeting room, an office, and a laboratory at 1.5 GHz with 50 ns time resolution to clarify the feasibility of a high-speed digital wireless communication system in an open-structure office room. Continuous power delay profile measurement revealed large variation of power delay profile in the same room. Measured RMS delay spread and mean excess delay were found to be dependent on the size of the room. Multi-reflection on walls was observed when received by a directional antenna. From these results, a simple propagation model for an indoor radio environment is proposed consisting of multi-wall-reflection waves with free space loss and wall-reflection loss, which describes the spatial variation of RMS delay spread.<>
{"title":"Multipath delay estimation for indoor wireless communication","authors":"T. Takeuchi, M. Sako, S. Yoshida","doi":"10.1109/VETEC.1990.110355","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110355","url":null,"abstract":"Multipath delay profile measurements were conducted in a meeting room, an office, and a laboratory at 1.5 GHz with 50 ns time resolution to clarify the feasibility of a high-speed digital wireless communication system in an open-structure office room. Continuous power delay profile measurement revealed large variation of power delay profile in the same room. Measured RMS delay spread and mean excess delay were found to be dependent on the size of the room. Multi-reflection on walls was observed when received by a directional antenna. From these results, a simple propagation model for an indoor radio environment is proposed consisting of multi-wall-reflection waves with free space loss and wall-reflection loss, which describes the spatial variation of RMS delay spread.<<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":"125208479","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.1990.110310
Kenji Imamura, K. Watanabe, K. Nagata
The problems involved in the introduction of MCS-12, NTT's second-generation cellular system, are described. These problems primarily lie in achieving the optimum balance between equipment cost and cell size. Existing design models are suitable for single cellular systems. It was proposed that the subscriber capacity model and the system cost model for single cellular systems can be applied to overlaid systems. Using the models, the optimum balance between cell radius and equipment cost can be determined for an overlaid system, so as to achieve the cheapest cost for each subscriber. If cellular systems are to be overlaid, the question of system compatibility cannot be avoided. The effects of the various compatibility schemes are discussed. A case study details the compatibility of NTT's MCS-L2 with the original MCS-L1 analog system.<>
{"title":"A study on system compatibility of land mobile communications systems","authors":"Kenji Imamura, K. Watanabe, K. Nagata","doi":"10.1109/VETEC.1990.110310","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110310","url":null,"abstract":"The problems involved in the introduction of MCS-12, NTT's second-generation cellular system, are described. These problems primarily lie in achieving the optimum balance between equipment cost and cell size. Existing design models are suitable for single cellular systems. It was proposed that the subscriber capacity model and the system cost model for single cellular systems can be applied to overlaid systems. Using the models, the optimum balance between cell radius and equipment cost can be determined for an overlaid system, so as to achieve the cheapest cost for each subscriber. If cellular systems are to be overlaid, the question of system compatibility cannot be avoided. The effects of the various compatibility schemes are discussed. A case study details the compatibility of NTT's MCS-L2 with the original MCS-L1 analog system.<<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":"133738449","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.1990.110336
N. Nakajima, M. Kuramoto, K. Kinoshita, T. Utano
The design parameters and experimental results for a proposed time-division multiple access (TDMA) digital mobile system are shown. The related network architecture, frame structure, and signaling structure for a digital system are given. The proposed system structure has three-slot TDMA, pi /4 shifted QPSK (quadrature phase shift keying), and 25 kHz carrier spacing. A spectrum-efficient system can be realized by using radio transmission techniques, such as diversity, bidirectional feed control amplifier, and robust CODECs. Field experiments have verified the digital transmission performance of this system. A signaling structure featuring service flexibility, such as ISDN service, is presented.<>
{"title":"A system design for TDMA mobile radios","authors":"N. Nakajima, M. Kuramoto, K. Kinoshita, T. Utano","doi":"10.1109/VETEC.1990.110336","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110336","url":null,"abstract":"The design parameters and experimental results for a proposed time-division multiple access (TDMA) digital mobile system are shown. The related network architecture, frame structure, and signaling structure for a digital system are given. The proposed system structure has three-slot TDMA, pi /4 shifted QPSK (quadrature phase shift keying), and 25 kHz carrier spacing. A spectrum-efficient system can be realized by using radio transmission techniques, such as diversity, bidirectional feed control amplifier, and robust CODECs. Field experiments have verified the digital transmission performance of this system. A signaling structure featuring service flexibility, such as ISDN service, is presented.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"24 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":"131925954","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.1990.110287
J. Rasinger, A. Scholtz, W. Pichler, E. Bonek
A novel internal antenna for hand-held mobile communications is presented. Topics covered include antenna bandwidth, description of the radiation-coupled dual-L antenna, the CAD system for wire-grid modeling, bandwidth, impedance, the shielding case, and the radiation pattern. This radiation-coupled dual-L antenna radiates isotropically, and offers a number of design options for impedance matching. Compared with an inverted-F antenna of equal height, its bandwidth is higher by at least 50%. Numerically calculated results based on a wire-grid model of this antenna agree well with measurement of bandwidth, input impedance, and radiation patterns. A major advantage of this antenna is its enhanced bandwidth without external matching networks in a small occupied volume.<>
{"title":"A new enhanced-bandwidth internal antenna for portable communication systems","authors":"J. Rasinger, A. Scholtz, W. Pichler, E. Bonek","doi":"10.1109/VETEC.1990.110287","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110287","url":null,"abstract":"A novel internal antenna for hand-held mobile communications is presented. Topics covered include antenna bandwidth, description of the radiation-coupled dual-L antenna, the CAD system for wire-grid modeling, bandwidth, impedance, the shielding case, and the radiation pattern. This radiation-coupled dual-L antenna radiates isotropically, and offers a number of design options for impedance matching. Compared with an inverted-F antenna of equal height, its bandwidth is higher by at least 50%. Numerically calculated results based on a wire-grid model of this antenna agree well with measurement of bandwidth, input impedance, and radiation patterns. A major advantage of this antenna is its enhanced bandwidth without external matching networks in a small occupied volume.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"8 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":"125187617","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.1990.110381
M. Minowa, M. Onoda, E. Fukuda, Y. Daido
The use of a nonlinear distortion canceller (NLDC) with a Cartesian feedback loop to improve the output backoff of an 800 MHz GaAs FET power amplifier when a quadrature phase shift keying (QPSK) signal with a rolloff factor of 0.5 is applied is described. This amplifier module uses three GaAs FETs. The amplifier's saturated power is 31 dBm, and its maximum power-added efficiency is 50%. Excellent operation of the NLDC was confirmed within a backoff range of more than 4 dB. Within this range, the out-of-band emission was kept 55 dB below the center frequency level. Since the peak output power coincides with the saturation power at a 4 dB backoff, the NLDC improves the backoff to the theoretical limit.<>
{"title":"Backoff improvement of an 800-MHz GaAs FET amplifier for a QPSK transmitter using an adaptive nonlinear distortion canceller","authors":"M. Minowa, M. Onoda, E. Fukuda, Y. Daido","doi":"10.1109/VETEC.1990.110381","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110381","url":null,"abstract":"The use of a nonlinear distortion canceller (NLDC) with a Cartesian feedback loop to improve the output backoff of an 800 MHz GaAs FET power amplifier when a quadrature phase shift keying (QPSK) signal with a rolloff factor of 0.5 is applied is described. This amplifier module uses three GaAs FETs. The amplifier's saturated power is 31 dBm, and its maximum power-added efficiency is 50%. Excellent operation of the NLDC was confirmed within a backoff range of more than 4 dB. Within this range, the out-of-band emission was kept 55 dB below the center frequency level. Since the peak output power coincides with the saturation power at a 4 dB backoff, the NLDC improves the backoff to the theoretical limit.<<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":"131483163","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.1990.110297
Y. Mori, H. Yabuki, M. Ohba, M. Sagawa, M. Makimoto, I. Shibazaki
Compact RF circuit modules using multilayered printed circuit boards (M-PCBs) are described. The theoretical analysis of split-ring resonators and spiral inductors, fundamental RF circuits elements embedded in M-PCBs, is presented. RF circuit modules, such as a frequency synthesizer, a phase-locked loop modulator, an up-converter, and a receiver front-end are demonstrated to be applicable to land mobile communication equipment. RF circuit modules using M-PCBs have a structure suitable for excellent antivibration characteristics, and the size of the newly developed modules has been reduced to one-quarter of that of conventional modules designed by surface-mount technology.<>
{"title":"Miniaturized RF-circuit modules for land mobile communication equipment","authors":"Y. Mori, H. Yabuki, M. Ohba, M. Sagawa, M. Makimoto, I. Shibazaki","doi":"10.1109/VETEC.1990.110297","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110297","url":null,"abstract":"Compact RF circuit modules using multilayered printed circuit boards (M-PCBs) are described. The theoretical analysis of split-ring resonators and spiral inductors, fundamental RF circuits elements embedded in M-PCBs, is presented. RF circuit modules, such as a frequency synthesizer, a phase-locked loop modulator, an up-converter, and a receiver front-end are demonstrated to be applicable to land mobile communication equipment. RF circuit modules using M-PCBs have a structure suitable for excellent antivibration characteristics, and the size of the newly developed modules has been reduced to one-quarter of that of conventional modules designed by surface-mount technology.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"42 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":"133957993","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.1990.110377
S. Ariyavisitakul
A low-complexity equalization technique for improving the reliability of portable radio links in the presence of multipath time delay spread is described. A technique that operates on hard-limited received signals, with only the phase information available, is presented. The use of passband hard-limiters in radio front end circuits reduces the complexity of portable radio receivers. An adaptive phase equalizer structure using decision-directed phase tracking which does not require the multiplication operations required in most conventional equalization algorithms is proposed. A receiver that includes a time-reversal structure and a joint estimator for optimum timing recovery and equalizer training is described. The time-reversal structure plays a crucial role in maximizing the compensation capability of the phase equalizer. The combined use of phase equalization and diversity reception is also considered. Computer simulations confirm the feasibility of the proposed receiver structure.<>
{"title":"Equalization of a hard-limited slowly-fading multipath signal using a phase equalizer with a time-reversal structure","authors":"S. Ariyavisitakul","doi":"10.1109/VETEC.1990.110377","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110377","url":null,"abstract":"A low-complexity equalization technique for improving the reliability of portable radio links in the presence of multipath time delay spread is described. A technique that operates on hard-limited received signals, with only the phase information available, is presented. The use of passband hard-limiters in radio front end circuits reduces the complexity of portable radio receivers. An adaptive phase equalizer structure using decision-directed phase tracking which does not require the multiplication operations required in most conventional equalization algorithms is proposed. A receiver that includes a time-reversal structure and a joint estimator for optimum timing recovery and equalizer training is described. The time-reversal structure plays a crucial role in maximizing the compensation capability of the phase equalizer. The combined use of phase equalization and diversity reception is also considered. Computer simulations confirm the feasibility of the proposed receiver structure.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"247 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":"134486447","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.1990.110379
H. Zhou, S. Yoshida, T. Takeuchi
An antenna pattern diversity reception (APDR) system with a selection strategy based on the measurement of cross-channel-interference which has been confirmed to be a linear function of the multipath RMS delay spread, assuming BPSK as an example, is proposed. Theoretical analysis and computer simulation have been performed to study the effects of an APDR system with minimum RMS delay spread branch-selection strategy. It is confirmed that such a system is more effective in reducing the RMS delay spread, broadening the coherence bandwidth, and decreasing bit error ratio (BER) than a system with a conventional maximum signal strength branch-selection strategy in severe frequency-selective fading environments. A field experiment was carried out. Based on the measured data and computer simulation, the proposed system is shown to work well, even in a real urban area.<>
{"title":"Selection diversity reception based on cross-channel-interference measurement for digital mobile radio","authors":"H. Zhou, S. Yoshida, T. Takeuchi","doi":"10.1109/VETEC.1990.110379","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110379","url":null,"abstract":"An antenna pattern diversity reception (APDR) system with a selection strategy based on the measurement of cross-channel-interference which has been confirmed to be a linear function of the multipath RMS delay spread, assuming BPSK as an example, is proposed. Theoretical analysis and computer simulation have been performed to study the effects of an APDR system with minimum RMS delay spread branch-selection strategy. It is confirmed that such a system is more effective in reducing the RMS delay spread, broadening the coherence bandwidth, and decreasing bit error ratio (BER) than a system with a conventional maximum signal strength branch-selection strategy in severe frequency-selective fading environments. A field experiment was carried out. Based on the measured data and computer simulation, the proposed system is shown to work well, even in a real urban area.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"38 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":"132195829","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.1990.110320
M.E. Margoudakis, T. Switzer
Northern Telecom has successfully demonstrated the operation of a time division multiple access (TDMA) demonstration system using six channels multiplexed onto a single RF carrier frequency and utilizing a nominal RF bandwidth of 30 kHz. This matches the analog FM bandwidth, and permits simple transition from existing RF channel assignments to digital channels. The architecture and operation of the digital cellular demonstration system are described. The demonstrations included two digital mobile units making simultaneous use of the system in either or both of two cells. Call set-up, hand-off, and disconnect were demonstrated by interfacing to the DMS-MTX, a standard configuration cellular switching system. Subscriber data transmission over the mobile radio channel at a rate of 9.6 kbit/s was also included as part of the demonstrations.<>
{"title":"Northern Telecom TDMA digital cellular demonstration system","authors":"M.E. Margoudakis, T. Switzer","doi":"10.1109/VETEC.1990.110320","DOIUrl":"https://doi.org/10.1109/VETEC.1990.110320","url":null,"abstract":"Northern Telecom has successfully demonstrated the operation of a time division multiple access (TDMA) demonstration system using six channels multiplexed onto a single RF carrier frequency and utilizing a nominal RF bandwidth of 30 kHz. This matches the analog FM bandwidth, and permits simple transition from existing RF channel assignments to digital channels. The architecture and operation of the digital cellular demonstration system are described. The demonstrations included two digital mobile units making simultaneous use of the system in either or both of two cells. Call set-up, hand-off, and disconnect were demonstrated by interfacing to the DMS-MTX, a standard configuration cellular switching system. Subscriber data transmission over the mobile radio channel at a rate of 9.6 kbit/s was also included as part of the demonstrations.<<ETX>>","PeriodicalId":366352,"journal":{"name":"40th IEEE Conference on Vehicular Technology","volume":"95 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":"132320222","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：