Pub Date : 1982-05-23DOI: 10.1109/VTC.1982.1623028
R. A. Isberg, J. C. Cawley, R. Chufo
The Bureau of Mines (BOM) has established a project to demonstrate means for improving underground communications in metal/nonmetal room and pillar mines. The Black River Mine, a large limestone mine near Butler, Kentucky, was selected for conducting propagation tests on 466 and 812 MHz and to develop a practical operating system. Tests of communications between handheld 2 watt ultra high frequency (UHF) transceivers in the mine proved satisfactory for approximately 2,000 feet (610 m) through straight and level haulageways but the range of communication into intersecting crosscuts was quite limited. It was evident that radiation from the transceivers was not being efficiently reflected by limestone pillars into the intersecting crosscuts. Two passive aluminum reflectors, each four feet (1.22 m) square, were installed near the roof and positioned 45° with respect to the axis at an intersection of two haulageways and the range of communications down the intersecting haulageways was significantly extended. Two distributed antenna and base station systems, each feeding four antennas located at principal intersections of haulage and travel roads, were installed and signal or fade margins above 20 dB quieting were measured to determine where reflectors were needed. The reflectors were very effective when they were within direct line of sight and less than 1,000 feet (305 m) from an antenna. The two antenna systems provided satisfactory coverage along the principal travel and haulageways in approximately 70 percent of the central portion of the mine but coverage was unreliable in the active mining areas around the perimeter of the mine. The alternatives of either installing four additional base station and distributed antenna systems or extending the original distributed antenna systems by adding two-way multichannel signal boosters to compensate for cable attenuation were evaluated. The signal booster concept was selected because it is less expensive, simpler to control, avoids hetrodyne interference and communications can be readily extended as the mined area is expanded.
矿务局制定了一个项目，以示范改善金属/非金属室矿和柱矿地下通讯的方法。肯塔基州巴特勒附近的一个大型石灰石矿Black River Mine被选中进行466和812 MHz的传播测试，并开发一个实用的操作系统。在矿井中进行的手持式2瓦超高频(UHF)收发器之间的通信测试证明，在大约2000英尺(610米)的范围内，通过笔直和水平的运输通道是令人满意的，但进入相交横断面的通信范围相当有限。很明显，从收发机发出的辐射没有被石灰石柱子有效地反射到相交的十字路口。两个被动铝反射器，每个四英尺(1.22米)的正方形，安装在屋顶附近，在两条轨道的交叉处与轴线呈45°角，并且在相交的轨道上的通信范围显着扩展。安装了两个分布式天线和基站系统，每个系统为位于运输和旅行道路主要十字路口的四个天线供电，并测量信号或衰减余量超过20 dB，以确定需要反射器的位置。当反射器处于直接瞄准线内且距离天线小于1000英尺(305米)时，反射器非常有效。这两种天线系统在矿井中央大约70%的主要旅行和运输道上提供了令人满意的覆盖，但在矿井周围的活跃矿区的覆盖不可靠。评估了安装四个额外的基站和分布式天线系统或通过增加双向多通道信号增强器来补偿电缆衰减来扩展原有分布式天线系统的替代方案。选择信号增强概念是因为它更便宜，更容易控制，避免外差干扰，并且随着雷区的扩大，通信可以很容易地扩展。
{"title":"The design and implementation of a UHF radio system using distributed antennas, passive reflectors and two-way signal boosters in a room and pillar limestone mine","authors":"R. A. Isberg, J. C. Cawley, R. Chufo","doi":"10.1109/VTC.1982.1623028","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623028","url":null,"abstract":"The Bureau of Mines (BOM) has established a project to demonstrate means for improving underground communications in metal/nonmetal room and pillar mines. The Black River Mine, a large limestone mine near Butler, Kentucky, was selected for conducting propagation tests on 466 and 812 MHz and to develop a practical operating system. Tests of communications between handheld 2 watt ultra high frequency (UHF) transceivers in the mine proved satisfactory for approximately 2,000 feet (610 m) through straight and level haulageways but the range of communication into intersecting crosscuts was quite limited. It was evident that radiation from the transceivers was not being efficiently reflected by limestone pillars into the intersecting crosscuts. Two passive aluminum reflectors, each four feet (1.22 m) square, were installed near the roof and positioned 45° with respect to the axis at an intersection of two haulageways and the range of communications down the intersecting haulageways was significantly extended. Two distributed antenna and base station systems, each feeding four antennas located at principal intersections of haulage and travel roads, were installed and signal or fade margins above 20 dB quieting were measured to determine where reflectors were needed. The reflectors were very effective when they were within direct line of sight and less than 1,000 feet (305 m) from an antenna. The two antenna systems provided satisfactory coverage along the principal travel and haulageways in approximately 70 percent of the central portion of the mine but coverage was unreliable in the active mining areas around the perimeter of the mine. The alternatives of either installing four additional base station and distributed antenna systems or extending the original distributed antenna systems by adding two-way multichannel signal boosters to compensate for cable attenuation were evaluated. The signal booster concept was selected because it is less expensive, simpler to control, avoids hetrodyne interference and communications can be readily extended as the mined area is expanded.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131650261","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 : 1982-05-23DOI: 10.1109/VTC.1982.1622996
G. Brusaglino
Fiat Research Center is developing, since several years, activities on electric and hybrid apparatuses. These has been applied on vehicles manufactured either for experimental or for pratical operation purposes. The development has been performed with particular consideration to energetical effectiveness, driving response and maintenance requirements, taking into account the economical aspect. The efficiency is achieved both through the drive system concept and the energy management strategy. The drive system for present applications are based on separately excited d.c. motors fed by electronic power conditioners. The particular features of the traction motors and the controllers with the possible diversified version for various applications are discussed in the paper. In the field of future technology, the approach with permanent magnets has been considered. Results on a permanent magnet d.c. motor are presented. The system development and integration as well as the control strategy is explained with reference to the Fiat 900E/E2 and the Iveco Daily E2 electric vans, having a payload of 1/2 ton and 1 ton respectively. The energy consumption of these vehicles measured at the mains is some 160 Wh/ton in urban operation. The operational aspect is discussed referred to driving response and maintenance. In the field of hybrids, the propulsion apparatus and the energy control strategy is described for a hybrid electric bus, developed in a program supported by the Italian National Research Council. It consists of a diesel electric generator unit, storage batteries and a separately excited d.c. motor with electronic controller. The system optimization strategy allowed an improvement of fuel economy in hybrid mode operation in urban areas in terms of 27% in comparison with the conventional version of the bus operating in the same conditions of payload and driving pattern.
{"title":"Operational and energetical effectiveness of road electric and hybrid propulsion","authors":"G. Brusaglino","doi":"10.1109/VTC.1982.1622996","DOIUrl":"https://doi.org/10.1109/VTC.1982.1622996","url":null,"abstract":"Fiat Research Center is developing, since several years, activities on electric and hybrid apparatuses. These has been applied on vehicles manufactured either for experimental or for pratical operation purposes. The development has been performed with particular consideration to energetical effectiveness, driving response and maintenance requirements, taking into account the economical aspect. The efficiency is achieved both through the drive system concept and the energy management strategy. The drive system for present applications are based on separately excited d.c. motors fed by electronic power conditioners. The particular features of the traction motors and the controllers with the possible diversified version for various applications are discussed in the paper. In the field of future technology, the approach with permanent magnets has been considered. Results on a permanent magnet d.c. motor are presented. The system development and integration as well as the control strategy is explained with reference to the Fiat 900E/E2 and the Iveco Daily E2 electric vans, having a payload of 1/2 ton and 1 ton respectively. The energy consumption of these vehicles measured at the mains is some 160 Wh/ton in urban operation. The operational aspect is discussed referred to driving response and maintenance. In the field of hybrids, the propulsion apparatus and the energy control strategy is described for a hybrid electric bus, developed in a program supported by the Italian National Research Council. It consists of a diesel electric generator unit, storage batteries and a separately excited d.c. motor with electronic controller. The system optimization strategy allowed an improvement of fuel economy in hybrid mode operation in urban areas in terms of 27% in comparison with the conventional version of the bus operating in the same conditions of payload and driving pattern.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132753617","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623007
R. Uppal, G. Edwards
This paper presents the results of a propagation study done in a treed rural environment, and compares the coverage areas in the 150, 410 and 850 MHz bands. The field measurements were done in Alberta utilizing one of Alberta Government Telephones radio relay sites, as the transmitting site. Initial tests in 1979 were limited to less than 20 km distance due to the non-availability of high power transmitting equipment in the 850 MHz band. Established computer projection programs were therefore utilized to project the coverage beyond that range. These computer projections were later verified by the use of high power transmitters in 1981. The results indicated a significant coverage penalty for the use of 850 MHz instead of 410 MHz. Optimum coverage was achieved at 150 MHz.
{"title":"Comparison of signal coverage for mobile radio systems in the 150, 410 and 850 MHz bands","authors":"R. Uppal, G. Edwards","doi":"10.1109/VTC.1982.1623007","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623007","url":null,"abstract":"This paper presents the results of a propagation study done in a treed rural environment, and compares the coverage areas in the 150, 410 and 850 MHz bands. The field measurements were done in Alberta utilizing one of Alberta Government Telephones radio relay sites, as the transmitting site. Initial tests in 1979 were limited to less than 20 km distance due to the non-availability of high power transmitting equipment in the 850 MHz band. Established computer projection programs were therefore utilized to project the coverage beyond that range. These computer projections were later verified by the use of high power transmitters in 1981. The results indicated a significant coverage penalty for the use of 850 MHz instead of 410 MHz. Optimum coverage was achieved at 150 MHz.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116828163","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623003
W. Fleming
Various methods of torque measurement which are utilized in the automotive industry are reviewed. Seven different methods are described in order of usage, starting with the most frequently used types and continuing to less frequently used types of torque measurement. Performance limitations for each method of torque measurement are also summarized in this paper.
{"title":"Automotive torque measurement: A summary of seven different methods","authors":"W. Fleming","doi":"10.1109/VTC.1982.1623003","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623003","url":null,"abstract":"Various methods of torque measurement which are utilized in the automotive industry are reviewed. Seven different methods are described in order of usage, starting with the most frequently used types and continuing to less frequently used types of torque measurement. Performance limitations for each method of torque measurement are also summarized in this paper.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128642697","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623052
J. A. Humphry, S.E. Smith
Redundancy and fault-tolerant computer technology are being applied to the development of a command and control system for automated vehicles. An ultrareliable command and control system is described which meets the availability and safety requirements for an automated transit system. The technology presented is applicable to a wide variety of computer-based controls where safety is involved or where interruption of the control process cannot be tolerated. High-performance computer-based controls are being developed by OTIS-TTD and Del Rey Systems to control the operation of automated transit systems. The command and control system will allow economical, flexible, personalized service while operating a large number of closely spaced (short headway) vehicles. The requirements for flexible service and short headway operation preclude the use of traditional failsafe design practices and components. To achieve the required performance, reliability, and safety, redundancy and fault-tolerant computer techniques are used. This paper describes how the reliability requirements for command and control systems are achieved through the application of fault tolerant computing. Three alternative computer architectures are described. Reliability analyses have been performed for each candidate architecture, and the results are presented. Based on the reliability analyses, a triple redundant computer is selected. Automatic failure detection and recovery is accomplished by software, thus allowing off-the-shelf hardware to be used.
{"title":"A fault-tolerant/fail-safe command and control system for automated vehicles","authors":"J. A. Humphry, S.E. Smith","doi":"10.1109/VTC.1982.1623052","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623052","url":null,"abstract":"Redundancy and fault-tolerant computer technology are being applied to the development of a command and control system for automated vehicles. An ultrareliable command and control system is described which meets the availability and safety requirements for an automated transit system. The technology presented is applicable to a wide variety of computer-based controls where safety is involved or where interruption of the control process cannot be tolerated. High-performance computer-based controls are being developed by OTIS-TTD and Del Rey Systems to control the operation of automated transit systems. The command and control system will allow economical, flexible, personalized service while operating a large number of closely spaced (short headway) vehicles. The requirements for flexible service and short headway operation preclude the use of traditional failsafe design practices and components. To achieve the required performance, reliability, and safety, redundancy and fault-tolerant computer techniques are used. This paper describes how the reliability requirements for command and control systems are achieved through the application of fault tolerant computing. Three alternative computer architectures are described. Reliability analyses have been performed for each candidate architecture, and the results are presented. Based on the reliability analyses, a triple redundant computer is selected. Automatic failure detection and recovery is accomplished by software, thus allowing off-the-shelf hardware to be used.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115661703","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623041
G. Hess
This paper discusses procedures for estimating the peak loads of trunked repeater systems. In addition to nominal peak load prediction, two aspects of overload are addressed: (1) system-to-system variation and (2) day-to-day variation. The procedures allow one to estimate the maximum communication load to be expected during a specified time interval for a specified fraction of trunked systems with equal mobile counts. One application of these procedures concerns the recent proposal of trunking at the 3 channel level. The results indicate that for most such systems to have viable grades-of-service, appreciably lower loading standards than exist today at the 5 channel level are necessary.
{"title":"Estimation of peak load on trunked repeater systems","authors":"G. Hess","doi":"10.1109/VTC.1982.1623041","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623041","url":null,"abstract":"This paper discusses procedures for estimating the peak loads of trunked repeater systems. In addition to nominal peak load prediction, two aspects of overload are addressed: (1) system-to-system variation and (2) day-to-day variation. The procedures allow one to estimate the maximum communication load to be expected during a specified time interval for a specified fraction of trunked systems with equal mobile counts. One application of these procedures concerns the recent proposal of trunking at the 3 channel level. The results indicate that for most such systems to have viable grades-of-service, appreciably lower loading standards than exist today at the 5 channel level are necessary.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116957070","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623012
D. Jansky
This paper sets forth the technical, policy, and regulatory framework in which the future of land mobile will be decided. It discusses the questions which must be answered, and makes several proposals on how to answer the questions.
{"title":"National directions in mobile communications","authors":"D. Jansky","doi":"10.1109/VTC.1982.1623012","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623012","url":null,"abstract":"This paper sets forth the technical, policy, and regulatory framework in which the future of land mobile will be decided. It discusses the questions which must be answered, and makes several proposals on how to answer the questions.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115031995","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623022
J. Durkin, D. Barnes
Details of user evaluation trials of a vhf 5 kHz single sideband (ssb) radio system are given together with an analysis of the results obtained. Details are also given of a subjective assessment of the performance of the system under co-channel interference conditions along with an objective comparison of the adjacent channel performance of the ssb equipment with existing am equipment in the United Kingdom.
{"title":"An evaluation of single sideband radio for use in VHF private land mobile radio services","authors":"J. Durkin, D. Barnes","doi":"10.1109/VTC.1982.1623022","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623022","url":null,"abstract":"Details of user evaluation trials of a vhf 5 kHz single sideband (ssb) radio system are given together with an analysis of the results obtained. Details are also given of a subjective assessment of the performance of the system under co-channel interference conditions along with an objective comparison of the adjacent channel performance of the ssb equipment with existing am equipment in the United Kingdom.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"211 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123018142","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623042
S. Ahmed, P. Constantinou
In this paper, a mathematical model is proposed to compute the duration of interference into a TV receiver, from a land mobile transmitter in the busy hour. Our objective is to determine how various parameters such as mobile density, traffic density, and distance will affect the probability that a transmitting mobile will degrade the picture quality of a TV receiver.
{"title":"A mobile interference model into UHF television receivers","authors":"S. Ahmed, P. Constantinou","doi":"10.1109/VTC.1982.1623042","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623042","url":null,"abstract":"In this paper, a mathematical model is proposed to compute the duration of interference into a TV receiver, from a land mobile transmitter in the busy hour. Our objective is to determine how various parameters such as mobile density, traffic density, and distance will affect the probability that a transmitting mobile will degrade the picture quality of a TV receiver.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123734765","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 : 1982-05-23DOI: 10.1109/VTC.1982.1623031
M. Sakamoto, S. Kozono, T. Hattori
A commercial service for an 800 MHz band fully automatic land mobile telephone system was initiated in Japan in 1979, and the number of subscribers is now over ten thousand. As the use of in-car mobile telephones become more wide spread, the demand for portable telephones will necessarily appear in the near future. Portable telephones can be introduced early and economically, if the service areas are outdoors and common mobile system base station equipment is utilized. In this paper, propagation characteristics for outdoor service portable telephones are first discussed. Diversity improvements of signal to noise ratio are shown for various combining methods, to compensate for portable telephone excess propagation loss. Using these results, portable telephone service quality is discussed when it is used with common mobile telephone system base station equipment. A new diversity antenna is proposed for base station diversity reception.
{"title":"Basic study on portable radio telephone system design","authors":"M. Sakamoto, S. Kozono, T. Hattori","doi":"10.1109/VTC.1982.1623031","DOIUrl":"https://doi.org/10.1109/VTC.1982.1623031","url":null,"abstract":"A commercial service for an 800 MHz band fully automatic land mobile telephone system was initiated in Japan in 1979, and the number of subscribers is now over ten thousand. As the use of in-car mobile telephones become more wide spread, the demand for portable telephones will necessarily appear in the near future. Portable telephones can be introduced early and economically, if the service areas are outdoors and common mobile system base station equipment is utilized. In this paper, propagation characteristics for outdoor service portable telephones are first discussed. Diversity improvements of signal to noise ratio are shown for various combining methods, to compensate for portable telephone excess propagation loss. Using these results, portable telephone service quality is discussed when it is used with common mobile telephone system base station equipment. A new diversity antenna is proposed for base station diversity reception.","PeriodicalId":230854,"journal":{"name":"32nd IEEE Vehicular Technology Conference","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124673389","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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