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Mobile Radio and Personal Communications, 1991., Sixth International Conference on

Date 9-11 Dec 1991

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Displaying Results 1 - 25 of 51
  • Improved adaptive Viterbi detectors for fast-varying mobile-radio channels

    Publication Year: 1991, Page(s):21 - 25
    Cited by:  Papers (2)  |  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (312 KB)

    The use of adaptive Viterbi detectors on fast-varying mobile-radio channels is studied. The main objective is to propose two new methods that may significantly improve the performance of the detector. The first method is to use prediction to combat the inherent delay of the channel estimates. The second method is to use so-called leaky algorithms in the channel estimator. This will make the detect... View full abstract»

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  • Cellular radio-telephone simulator

    Publication Year: 1991, Page(s):121 - 125
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (256 KB)

    Describes the cellular radio-telephone simulator which is being enveloped at BNR Europe Limited (which incorporates STL) as part of a DTI LINK programme. In order to illustrate some of the features of the simulator, two forms of channel allocation strategy and power control are considered, and results are presented View full abstract»

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  • Microcellular radio modelling

    Publication Year: 1991, Page(s):182 - 190
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (320 KB)

    First generation cellular radio systems are now failing to support the increased demand from all sectors of the public. The problem of congestion is at its most severe in dense urban areas such as city centres, and on some motorways. A promising idea that has the potential to provide a solution is the microcellular approach. The authors describe the development of a microcellular propagation model... View full abstract»

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  • An analytical model for indoor multipath propagation in the picocellular environment

    Publication Year: 1991, Page(s):1 - 8
    Cited by:  Papers (6)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (416 KB)

    Presents a deterministic algorithm for the prediction of channel characteristics for small cell radio systems. This is achieved through the application of ray tracing techniques on a simplified 3-D description of a given environment. The model has been shown to agree well with wideband measurements made at the University of Bristol. The model has been used to generate narrowband data, Doppler scat... View full abstract»

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  • Diversity signal processing requirements of direct sequence CDMA networks in cellular and micro-cellular environments

    Publication Year: 1991, Page(s):68 - 73
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (92 KB)

    The diversity signal processing requirements versus bandwidth efficiency of CDMA are examined for various mobile operational environments. An analytical performance model is employed to assess the spectrum efficiency aspects of various CDMA transceiver architectures operating in both rural and urban cellular environments, as well as micro-cellular network topologies. From the results presented, it... View full abstract»

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  • Study into the use of search, vote and lock for Metropolitan Police personal radio systems

    Publication Year: 1991, Page(s):197 - 202
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (296 KB)

    The Metropolitan Police Service intends to replace its current VHF network of divisional and specialist personal radio systems with a network operating on UHF assignments. The re-engineering program involves over 10000 handheld radios and fixed equipment at over 400 sites. The authors reports on recent work carried out to assess the operational and engineering aspects concerned with achieving wide... View full abstract»

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  • DCS1800-the standard for PCN

    Publication Year: 1991, Page(s):175 - 181
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (400 KB)

    The new standard known as Digital Cellular System at 1800 MHz (DCS 1800) was developed within ETSI GSM and Phase I was approved in February 1991. Subsequently work has continued on a combined DCS/GSM work programme in order to provide improved features and techniques based on a merged set of recommendations. The authors describe enhancements incorporated into the new standard to support PCN (perso... View full abstract»

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  • Low-cost direct conversion receiver structures for TDMA mobile communications

    Publication Year: 1991, Page(s):143 - 150
    Cited by:  Papers (5)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (380 KB)

    Future public land mobile telecommunication systems (FPLMTS) with robust digital transmission will require cheap, small, and low-power mobile terminals. This goal can be reached by a receiver architecture which lends itself to VLSI and which does not require any adjustments during the production process. The authors have studied a number of direct-conversion receiver structures. A receiver based o... View full abstract»

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  • The performance of DECT in the outdoor 1.8 GHZ radio channel

    Publication Year: 1991, Page(s):300 - 307
    Cited by:  Papers (25)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (612 KB)

    The authors looks at the application of the DECT standard to outdoor public access systems (e.g. cordless access and telepoint) and the technical issues raised by its deployment in outdoor environments. They aim to fully characterise propagation conditions in a typical telepoint area and then to accurately predict the DECT link performance for such an environment. Conclusions are drawn as to the m... View full abstract»

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  • Experimental results from the UK test-bed on the DCS1800 radio channel

    Publication Year: 1991, Page(s):9 - 15
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (304 KB)

    A collaborative LINK research project has been in progress since early 1990 to develop the DCS1800 test bed and use this equipment to investigate the radio path performance of a GSM-type TDMA system at 1.8 GHz. Prior to this programme, Orbitel possessed a 900 MHz digital cellular radio test-bed to verify the operation of the GSM system to be implemented throughout Europe. This test-bed was upgrade... View full abstract»

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  • Driver information systems-a new market?

    Publication Year: 1991, Page(s):267 - 271
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (300 KB)

    The author provides an overview of some of the key technological issues and market constraints affecting the growth of driver information and navigation systems in the short to medium term. He covers trends in relevant technologies, generic markets for driver information systems, technical constraints on product development, issues affecting user demand, directions of growth, and identifies some k... View full abstract»

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  • A spectrum efficient cellular base-station antenna architecture

    Publication Year: 1991, Page(s):272 - 279
    Cited by:  Patents (25)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (600 KB)

    A multiple beam adaptive base-station antenna is proposed to complement other solutions, such a spectrum efficient modulation, currently being developed to meet the proliferating demands for enhanced capacity in mobile communications. This novel approach employs an antenna array capable of resolving the angular distribution of the mobile users as seen at the base-station site, and then utilising t... View full abstract»

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  • The regulation of mobile communications

    Publication Year: 1991, Page(s):131 - 135
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (352 KB)

    Mobile communications are at the forefront of changes in the telecommunications regulatory environment, and are also affected in more ways than any other service. The following topics are discussed: use of the spectrum; regulation for competition; personal communications; regulation in practice; and the regulator's role View full abstract»

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  • Transmission planning for mobile telecommunication systems

    Publication Year: 1991, Page(s):126 - 130
    Cited by:  Papers (4)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (332 KB)

    Describes the various transmission planning parameters and how they are apportioned within mobile communications systems. The limits that are set on these parameters to provide acceptable speech quality for the customer, be he a fixed or mobile subscriber, are discussed. In some areas the limits are well defined in European and global standards. However, mobile communications networks are introduc... View full abstract»

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  • Delivering cordless telephony in the access network using `fibre-radio'

    Publication Year: 1991, Page(s):45 - 48
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (184 KB)

    A method of delivering cordless access is described, in which a radio distribution point (DP) is fed by an analogue optical link. Using sub-carrier multiplexing the radio path between the handset and the cordless fixed part is extended over single-mode optical fibre, in a system known as `fibre-radio'. The call processing and other functions such as frequency conversion may therefore be located at... View full abstract»

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  • Simulation of man-made noise in 100 MHz to 3 GHz band

    Publication Year: 1991, Page(s):255 - 260
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (336 KB)

    The authors describe the physical nature of impulsive noise and its simulation. The RF part and digital part of the simulator are described. Man-made impulsive noise environments were simulated and output impulsive noise was measured using noise amplitude distribution (NAD) measuring equipment. The results were in excellent agreement with measured results. The simulator was used to assess the perf... View full abstract»

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  • Link control in terrestrial/satellite mobile communication systems

    Publication Year: 1991, Page(s):77 - 81
    Cited by:  Patents (8)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (484 KB)

    Algorithms and signalling requirements of procedures for link selection and handover are discussed, both for terrestrial and satellite land mobile communications. For terrestrial cellular systems the methods are well known in principle, it is argued that similar procedures could also be employed in satellite multi-beam systems. Choice of terrestrial or satellite links in integrated dual mode syste... View full abstract»

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  • Analysis of decision-aided DPSK in the presence of multipath fading

    Publication Year: 1991, Page(s):157 - 162
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (272 KB)

    A decision-aided DPSK receiver scheme is proposed, which can achieve channel equalization using data symbols alone (i.e. no additive reference information is required). It makes use of the fact that for a typical irreducible error rate of 1%, 99% of the received symbols are correctly demodulated. Using this information to remove the modulation from the incoming radio signal effectively results in ... View full abstract»

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  • The application of 16APSK to mobile fading channels

    Publication Year: 1991, Page(s):233 - 240
    Cited by:  Papers (8)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (456 KB)

    Data transmission in the mobile environment is particularly susceptible to the distortion introduced by the propagating channel. The authors concentrated on 16APSK, which utilises two concentric 8-PSK rings to greatly simplify the process of differential reception. Both differentially encoded and differentially demodulated 16APSK are examined (16DEAPSK and 16DAPSK respectively) together with metho... View full abstract»

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  • Introducing personal communications in the developing countries: alternatives and issues

    Publication Year: 1991, Page(s):208 - 211
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (212 KB)

    In planning services in developing countries, the major issues that need to be tackled are: rapid technological growth, a large number of standards and regulatory/financial constraints. The authors touch upon the alternatives and various issues involved in introducing personal communication services in developing countries for both mobile communication and rural/remote area communication through f... View full abstract»

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  • Aspects of combined coding and linear modulation and its application to future personal communication systems

    Publication Year: 1991, Page(s):87 - 92
    Cited by:  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (272 KB)

    The possibility of applying MECLCs (M-ary error correcting line codes) in conjunction with SSB transmission and linear modulation schemes is examined. Such schemes are considered to be potentially of interest for future personal communication systems. A new class of error correcting codes with defined spectra was introduced; such codes provide error control as well as a null at DC and suppressed l... View full abstract»

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  • Fast VQ-CELP-a speech coder for mobile radio

    Publication Year: 1991, Page(s):280 - 285
    Cited by:  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (244 KB)

    The currently emerging generation of mobile radio systems employs digital speech transmission techniques to achieve higher system capacity than analogue systems. Therefore methods of transmitting high quality digital speech signals at low bit rates are of great interest in such applications. The CELP (code excited linear prediction) algorithm is a good basis for meeting this requirement. However, ... View full abstract»

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  • Tree attenuation measurements at 1-4 GHz for mobile radio systems

    Publication Year: 1991, Page(s):16 - 20
    Cited by:  Papers (5)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (164 KB)

    Reports measurements of the attenuation induced by trees on satellite-like paths over a wide range of frequencies (1-4 GHz). These measurements can be used to evaluate the comparable performance of mobile satellite systems at different elevation angles and over a wide frequency range. They can also provide a further insight into the applicability of the empirical formula on vegetation effects quot... View full abstract»

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  • Frame by frame transmission and detection techniques for a mobile radio channel

    Publication Year: 1991, Page(s):101 - 107
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (400 KB)

    Considers packet data transmission over radio channels. A worst case model of a mobile radio channel is used. A useful adaptive matched-filter detection technique useful for this kind of channel with several independent fading paths has been used and found to work satisfactorily Two methods of frame by frame detection are presented. It has also been found that if the stored vectors in the modified... View full abstract»

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  • A 1.8 GHz synthesiser for use in mobile radio

    Publication Year: 1991, Page(s):136 - 142
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (400 KB)

    Presents the design of a synthesiser based on a single phase locked loop, and capable of output frequencies of over 2 GHz, aimed at the portable radio market. Experimental results are presented for a prototype unit demonstrating the success of techniques to reduce the levels of phase noise and sidebands. These techniques are outlined and the results are analysed in detail. A new circuit configurat... View full abstract»

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