By Topic

IEEE 39th Vehicular Technology Conference

1-3 May 1989

Filter Results

Displaying Results 1 - 25 of 141
  • 39th IEEE Vehicular Technology Conference (IEEE Cat. No.89CH2739-1)

    Publication Year: 1989
    Request permission for commercial reuse | PDF file iconPDF (41 KB)
    Freely Available from IEEE
  • The performance of GTFM in a frequency-selective Rayleigh fading channel

    Publication Year: 1989, Page(s):878 - 883 vol.2
    Cited by:  Papers (1)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (513 KB)

    Generalized tamed frequency modulation (GTFM) is a bandwidth-efficient digital modulation technique suitable for use in land mobile radio systems. The authors examine the influence of both frequency-flat and frequency-selective Rayleigh fading on GTFM with discriminator detection. In addition, the effects of cochannel and adjacent channel interference are considered in the frequency-flat fading ch... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Short-block equalization techniques employing channel estimation for fading time-dispersive channels

    Publication Year: 1989, Page(s):142 - 146 vol.1
    Cited by:  Papers (10)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (452 KB)

    The objective of the present study is reliable digital communications over fading channels with severe time-dispersion. The authors present three short-block equalization techniques based on linear, nonlinear decision-directed, and maximum-likelihood estimation principles. Short alternating blocks of data and training symbols are used. In contrast to the recursive symbol-by-symbol equalization app... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • System design for portable telephones: methods to enable initiating and receiving calls from a vehicle

    Publication Year: 1989, Page(s):136 - 141 vol.1
    Cited by:  Papers (3)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (448 KB)

    The author proposes the application of the small zone format which adapts the microcell for plural position-registration as one step in realizing a portable telephone set method for communicating at any time, at any place, and to anywhere by using cordless telephones with small (10 mW) output power. Another proposal is to install cordless-telephone key service units on poles along the streets in s... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimum pre-emphasis for FM transmission with frequency-domain voice scrambling

    Publication Year: 1989, Page(s):206 - 211 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (376 KB)

    Optimum pre- and de-emphasis are theoretically investigated for FM and PM transmission, including frequency-domain scrambling for voice security. Using a linear system model, the optimum frequency characteristics for pre- and de-emphasis filters are given as functions of the voice signal spectrum, demodulator output noise spectrum, and the scrambling method. Comparisons of the maximum attainable S... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Cellular models and hand-off criteria

    Publication Year: 1989, Page(s):128 - 135 vol.1
    Cited by:  Papers (10)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (456 KB)

    The authors consider methods of improving the hand-off process in current cellular systems, particularly in large cities where the cell size is smaller, in order to increase the capacity and service high subscriber traffic density. In this case, the mobiles will cross all boundaries more often, leading to a high number of hand-offs; a hand-off based only on the strongest received signal is not nec... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application engineering considerations for cellular repeaters

    Publication Year: 1989, Page(s):532 - 534 vol.2
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (164 KB)

    The author presents some real-life examples demonstrating the system engineering used in installing cellular repeaters. The examples given includes stretches of freeway, golf courses, tunnels and convention centers. It is concluded that cellular repeaters can be used to improve coverage on a cost-effective basis in rural areas, downtown in major cities and in all types of environments from desert ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Management standards for communication sites

    Publication Year: 1989, Page(s):201 - 205 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (392 KB)

    The authors attempts to define all components of quality for the communication site and describes how they lead to site standards and management techniques. The site standards include location of antennas, installation of jacketed coax, double-shielded pigtails, connectors, isolators, cavities, preselectors, combining of frequencies, grounding, and adopting a management standards policy. The prima... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comparison of different hand-over strategies for high capacity cellular mobile radio systems

    Publication Year: 1989, Page(s):122 - 127 vol.1
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (384 KB)

    Preliminary results are presented for a computer program, which has already been used for spectrum efficiency evaluations, that starting from a dynamic traffic model gives interesting information on system performance when different hand-over criteria are used. The proposed simulation program is able to evaluate hand-over characteristics for strategies based on field strength, distance, and C/I (c... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A high efficiency 835 MHz linear power amplifier for digital cellular telephony

    Publication Year: 1989, Page(s):17 - 18 vol.1
    Cited by:  Papers (18)  |  Patents (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (120 KB)

    The authors describe an approach to linear power amplification for digital cellular telephony which exploits the high efficiency of a class-C amplifier. An average efficiency exceeding 50%, with third-order intermodulation products 30 dB down, has been demonstrated. Low cost, moderate complexity, conventional RF technology was used in the amplifier circuitry. A block diagram of the 835 MHz linear ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application of second-order statistics for an indoor radio channel model

    Publication Year: 1989, Page(s):888 - 892 vol.2
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (436 KB)

    The secondary statistics for an indoor radio impulse response model in the factory environment are investigated. Under the assumption that multipath signal amplitudes are jointly log-normally distributed over local areas and excess delay, the application of second-order statistics (correlation) is presented. In addition, the distributions of received power within a particular excess delay interval... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On frequency radio (OFR) repeater as fade filler

    Publication Year: 1989, Page(s):528 - 531 vol.2
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (284 KB)

    The on-frequency radio repeater is proposed as a solution to the problem of filling in coverage holes in mobile (particularly portable) communications. The basic conceptual design of the OFR repeater is described; its limitations are discussed; and some of its typical applications (building coverage and outside fade filler) are noted View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Quality antenna site management [land mobile radio]

    Publication Year: 1989, Page(s):195 - 200 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (992 KB)

    The author provides a fairly nontechnical portrayal of his experience in managing an antenna site in Jacksonville. The company's strategy to achieve business success through quality is outlined. The following elements of the strategy are described in detail: (1) premium site, (2) master antenna system, (3) quality installation, (4) resident site manager, and (5) control of interference View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Trends of digital signal processing in automotive

    Publication Year: 1989, Page(s):613 - 624 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (644 KB)

    The author first discusses digital signal processing (DSP) characteristics. After reviewing historical digital signal processing solutions, he focuses on single-chip programmable digital signal processors and compares their architectural designs to those of general-purpose microprocessors and microcontrollers. Deficiencies of early digital signal processors are discussed and trends of DSP are expl... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Differential detection of partial response continuous phase modulation with index 0.5

    Publication Year: 1989, Page(s):115 - 121 vol.1
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (412 KB)

    The author presents a method for the design of an MMSE (minimum mean-squared error) optimum receiver filter for the differentially coherent detection of CPM (continuous phase modulation) with modulation index 0.5. The receiver filter is equivalent to the cascade of a matched filter and an equalizer, to reduce inherent intersymbol interference (ISI). The performance can be improved when the delay b... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evaluate digital cellular systems

    Publication Year: 1989, Page(s):7 - 10 vol.1
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (192 KB)

    It is suggested that, to evaluate digital cellular systems, it is necessary to agree upon a general standard environment for testing. The speech quality is the major factor to be evaluated. Based on speech recognition and speaker recognition, the speech quality should be evaluated by an established evaluation center. Based on a standard speech quality, the required carrier-to-interference ratio (C... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Feasibility of robotic cleaning of the undersides of Toronto subway cars

    Publication Year: 1989, Page(s):884 - 887 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    A description is given of a feasibility study which clearly indicated that robotics for undercar cleaning is indeed viable, both technically and economically. The proposed final system will combine water and air cleaning in the existing degreasing bay suitably modified by the addition of a second platform and appropriate walls and doors. Three robots will be used (one in the center and two on the ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Propagation considerations of low power cellular boosters and case histories

    Publication Year: 1989, Page(s):523 - 527 vol.2
    Cited by:  Papers (3)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (528 KB)

    Booster site selection often has tighter constraints placed upon it than cell site selection. Low-power 800-MHz cellular boosters usually provide a 250 mW ERP (effective radiated power) and are located several miles from the donor cell site. Two propagation problems must be analyzed, the donor-to-booster path loss and the booster coverage contour. In either case, the typical propagation model (e.g... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Driver guidance-an enhancement or a requirement in automatic vehicle location (AVL) systems

    Publication Year: 1989, Page(s):192 - 194 vol.1
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (256 KB)

    Arguments are presented to show why driver guidance (DG) should be a requirement for AVL systems. The navigator functions and cost-effectiveness of DG are described. It is concluded that AVL with driver guidance provides direct benefits to the driver, thus making the AVL system perceivable as a tool to make the job easier, not as a management method of `spying' and that driver guidance saves time,... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Noncoherent detection of π/4-QPSK systems in a CCI-AWGN combined interference environment

    Publication Year: 1989, Page(s):83 - 94 vol.1
    Cited by:  Papers (26)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (708 KB)

    The performance of π/4-QPSK modems in a cochannel interference (CCI) and additive white Gaussian noise (AWGN) environment is studied. Three differential detection models are described and modified to improve the BER (bit error rate) performance of the detector: (1) baseband differential detection, (2) IF (intermediate frequency) band differential detection, and (3) FM-discrimination detection. ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Correlation properties of antenna diversity in indoor mobile communication environments

    Publication Year: 1989, Page(s):446 - 451 vol.2
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (324 KB)

    The correlation properties of polarization diversity in indoor environments are investigated theoretically and experimentally. A statistical distribution model of incident waves which is uniform in azimuth and Gaussian in elevation is assumed and typical correlation characteristics of cross dipole antennas are described theoretically. The values for the propagation parameters which provide for low... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Cummins electronic controls for heavy duty diesel engines

    Publication Year: 1989, Page(s):595 - 612 vol.2
    Cited by:  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1304 KB)

    Heavy-duty diesel engines with the PACE limited-authority electronic control are on the road in some quantity, while Cummins is also introducing the Electronically Controlled Injection full-authority system on its engines. The authors describe these engine controls and show how a family of products concept is resulting in a smooth introduction of this technology into the heavy-duty diesel-powered ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Human factor design criteria for ATCS onboard terminals

    Publication Year: 1989, Page(s):701 - 707 vol.2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (500 KB)

    Human factor activities for the development of MMI (man-machine interface) equipment and related displays are suggested with emphasis on the equipment's applicability to the railroad industry. The author provides the framework for the application of human factors principles and criteria during progressing stages of system development. He summarizes the present state of the art methods for human fa... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Radio channel structure for QPSK digital mobile radio

    Publication Year: 1989, Page(s):220 - 223 vol.1
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (336 KB)

    Experiments on QPSK (quadrature phase-shift keying) signal transmission and 8 kb/s TC-WVQ (transform coding with weighted vector quantization) speech coding are presented. Computer simulation of the TC-WVQ speech codec has shown that the subjective quality is comparable to that of 5-bit log PCM (pulse code modulation) at a channel bit error rate of 10-2. Computation complexity can be gr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Hybrid trellis-coded 8/4-PSK systems

    Publication Year: 1989, Page(s):106 - 114 vol.1
    Cited by:  Papers (2)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (664 KB)

    It is shown how trellis-coded 8-PSK (phase-shift-keying) signals can be modified to become more robust against carrier phase variations, thus allowing more stable carrier recovery. A more robust performance can be achieved by using rate 2/3 trellis-coded 8-PSK and 4-PSK signals in a time-varying manner. In its simplest form, trellis-coded 8-PSK and 4-PSK signals alternate in time. The distance spe... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.