By Topic

Personal, Indoor and Mobile Radio Communications, 1992. Proceedings, PIMRC '92., Third IEEE International Symposium on

Date 19-21 Oct. 1992

Filter Results

Displaying Results 1 - 25 of 132
  • Proceedings of 2nd International Symposium on Personal, Indoor and Mobile Radio Communications

    Publication Year: 1992
    Request permission for commercial reuse | PDF file iconPDF (69 KB)
    Freely Available from IEEE
  • Equalizer performance with diversity for U.S. digital cellular

    Publication Year: 1992, Page(s):255 - 259
    Cited by:  Papers (4)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (376 KB)

    In mobile communications, the receiver must mitigate severe signal impairments arising from multipath and Rayleigh fading. Multipath produces intersymbol interference (ISI), necessitating the use of an equalizer in the receiver. The performance of the equalizer can be significantly improved using antenna diversity, thereby allowing the use of lower C/I values. This C/I reduction offers potential f... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance analysis of a digital mobile communication system

    Publication Year: 1992, Page(s):189 - 193
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (300 KB)

    The aauthors present a performance study of a digital mobile communication system (DMCS) which is a two-way radio frequency data communication network. The purpose of this modeling (multi-server queueing) effort is to provide the mean inbound and outbound message delays under different traffic intensities. Due to the acknowledgement and retransmission mechanism, the inbound and outbound traffic in... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An adaptive maximum-likelihood sequence estimation receiver with dual diversity combining/selection

    Publication Year: 1992, Page(s):245 - 249
    Cited by:  Papers (7)  |  Patents (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (380 KB)

    An adaptive maximum-likelihood sequence estimation (MLSE) receiver with dual diversity combining/selection is studied. The proposed receiver employs two independent channel impulse response estimators, with each estimator estimating one channel only. The likelihood metrics are calculated from the received signals by using independently estimated channel parameters. In diversity combining, metrics ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Propagation over buildings for paths oblique to the street grid

    Publication Year: 1992, Page(s):75 - 79
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (364 KB)

    Prediction of cell shape is important for proposed microcellular systems employing base station antennas at or below the surrounding rooftops. For residential and commercial areas, where the buildings are of nearly uniform height, prediction of cell shape will require knowledge of how the average signal received by street level mobiles depends on the direction of propagation relative to the rows o... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance of direct sequence CDMA orthogonal codes over measured indoor radio channels

    Publication Year: 1992, Page(s):470 - 475
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (320 KB)

    Direct sequence code division multiple access (CDMA) with orthogonal codes is under consideration for use in indoor radio communications. Spread spectrum with its inherent resistance to multipath and orthogonal codes for increased bandwidth efficiency make this implementation attractive. This paper analyzes the performance of such a system using actual channel measurements rather than the usual as... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A framework for specifying a physical layer and medium for wireless local area networks

    Publication Year: 1992, Page(s):149 - 152
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (404 KB)

    A conceptual framework for specifying a physical layer and a medium for a wireless local area network is detailed. This framework defines a physical layer entity consisting of a medium independent sublayer, a physical convergence sublayer and a medium dependent sublayer. The action of this physical layer entity is to provide a bidirectional mapping between the information present at the media acce... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The generation of bandwidth efficient modulation schemes using direct digital synthesis

    Publication Year: 1992, Page(s):393 - 396
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (236 KB)

    This paper describes the generation of bandwidth efficient modulation techniques for indoor wireless communication and other applications using direct digital synthesis. Direct digital synthesis is an attractive alternative to traditional implementation methods. It allows the generation of efficient and easily modifiable modulation schemes. The Hewlett Packard Frequency Agile Signal Simulator (HPF... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pitch-tracked CELP speech coding with transparent DTMF signaling

    Publication Year: 1992, Page(s):670 - 674
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (452 KB)

    A diagnostic analysis was conducted on code-excited linear prediction (CELP)-coded speech at 4.8 kbit/s for mobile radio communications. The occasional roughness in CELP-coded speech was traced to pitch contour infidelity, as well as the discontinuity of speech spectra. The use of a first-order integer-valued pitch filter also degraded the coded speech. A pitch-tracked CELP (PT-CELP) coding scheme... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A multiple access protocol for indoor wireless communications in factories

    Publication Year: 1992, Page(s):296 - 302
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (504 KB)

    The authors propose an architecture for incorporating mobile data users into an existing MAP/TOP system. The scheme involves attaching a small number of radio base stations to the TOP network through which the mobiles may access the system. The system's central feature is a new distributed, multi-receiver, multiple access protocol used by the mobiles to access the bases. The protocol permits users... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Soft decision decoding of a bit-interleaved convolutionally encoded code division multiple access system over Rayleigh fading channels

    Publication Year: 1992, Page(s):128 - 132
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (324 KB)

    The author investigates the performance of a bit-interleaved convolutionally encoded code division multiple access (CDMA) communication system with feedback power control over mobile radio channels. The analytical formulas for both optimal and suboptimal bit likelihood ratios, to be used as soft decision metrics for the decoder, are derived for noncoherent detection, with and without diversity rec... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evaluating pay-telephone service on coastal ferries

    Publication Year: 1992, Page(s):69 - 74
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (424 KB)

    Reports the statistical results of RMS delay spreads obtained from the impulse response measurements on the propagation channels of two ferry routes. Some interesting impulse responses measured as the ferry was passing through regions where multipath echoes are known to be very active are also presented. The two ferry routes measured were F2 and F1 in Vancouver. Route F2 runs from Horseshoe Bay to... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evolving the personal communicator

    Publication Year: 1992, Page(s):339 - 343
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (332 KB)

    Given that the vision for the future is of personal communicators providing ubiquitous access to telephony and other services, this paper proposes a strategy which enables the initial evolutionary steps to be made from a wireline subscriber base-the situation in which the majority of telecommunications service providers find themselves. The concept presented facilitates the next step, beyond simpl... View full abstract»

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

    Publication Year: 1992, Page(s):377 - 381
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (344 KB)

    In next generation mobile satellite systems very high spectrum efficiency will be a primary objective. High spectrum efficiency is often related to a significant amount of co-channel and/or adjacent channel interference. Therefore, system design should in general include consideration of both interference and noise effects. Interference evaluation in a mobile satellite cellular system is different... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bit error rate in FH/BFSK system under jamming environments

    Publication Year: 1992, Page(s):465 - 469
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (208 KB)

    The BER (bit error rate) is measured for an estimation of the performance of the frequency hopping systems under partial band jamming and single tone jamming signals, and a real system is made for the purpose of measurement. The FH/BFSK communication technology is used for the computer simulation and the real system. The performance of the actual frequency hopping system is tested and also the cap... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The capacity region for the Gaussian channel with random multipath

    Publication Year: 1992, Page(s):483 - 487
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (368 KB)

    In order to provide the decoder with essential information on the channel state, and improve the effectiveness of the communication, a probabilistic analysis of the communication channel is needed. Such modeling must include fading and multipath, as well as interference. An insight into the behavior of the channel can be gained by attempting an information theoretical approach for the multipath mo... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Hand-off analysis for an integrated satellite and terrestrial mobile system over a fading channel

    Publication Year: 1992, Page(s):397 - 401
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (280 KB)

    An integrated satellite and terrestrial mobile system enables the satellite mobile terminal (MT) to access the land mobile satellite system (LMSS) inside the coverage of a terrestrial network. When the MT operates inside an urban area, base stations of the terrestrial network will act as relay stations for the LMSS. The hand-off analysis for the two systems is an important issue. A mathematical mo... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reed-Solomon coded QAM modulation on a Rayleigh fading channel

    Publication Year: 1992, Page(s):591 - 595
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (344 KB)

    The authors propose the design of a coded transmission system for the terrestrial urban radio channel, with a 4 bit-spectral efficiency. They evaluated the performances of a Reed-Solomon coded 64-QAM modulation on a Rayleigh fading channel. Three decoding algorithms are considered: a hard decision and an erasure Berlekamp-Massey decoding algorithm and a soft decision maximum likelihood decoding al... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical power budget on quasi-diffuse IR WLANs

    Publication Year: 1992, Page(s):159 - 163
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (280 KB)

    Current activities for wireless indoor networks are concerned with wireless LANs (WLANs). Two technologies are suitable for WLAN systems: RF signals and IR. Focusing on IR WLANs, quasidiffuse links work with a point-to-point link from the IR emitter to the passive reflector and with a diffuse link from this reflector. The authors deal with the study of an IR Q-diffuse system for data transmission.... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A proposed access method for the wireless LAN standard

    Publication Year: 1992, Page(s):145 - 148
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (208 KB)

    The attempt by the IEEE802.11 wireless LAN standard to fulfil the user anticipated performance expectations has imposed a challenging demand on its access method selection. To utilize the valuable shared spectrum resources effectively, a demand assigned multiple access method is proposed to meet this goal. The method is tailored to suit the key requirement specifications which are at present being... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Coexistence of DS CDMA PCN and analog FM: performance degradation of the SSSC-FM channels due to spread spectrum overlay

    Publication Year: 1992, Page(s):665 - 669
    Cited by:  Papers (3)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (312 KB)

    The spectrum overlay of a CDMA PCN on a preexisting narrowband, analog, corrupted by AWGN FM channel is considered. This overlay can increase communications capacity, within a geographical area, and spectral efficiency. The overlayed PCN is assumed to employ DS spreading, using maximal length pseudorandom sequences. The interference the FM channel experiences is estimated, and an extremely severe ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A full digital modem for offset type modulation schemes

    Publication Year: 1992, Page(s):596 - 599
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (280 KB)

    This paper proposes a full digital modem employing a reverse-modulation type carrier recovery scheme for offset type modulation schemes. The full digital modem employs a wave forming filter for reverse-modulation of offset type modulated signals to increase the extracted carrier signal-to-noise ratio. The proposed modem achieves both high speed carrier acquisition and low carrier slipping rate sim... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Packet synchronization and identification for incremental redundancy transmission in FH-CDMA systems

    Publication Year: 1992, Page(s):292 - 295
    Cited by:  Patents (56)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (264 KB)

    Incremental redundancy transmission is an efficient data communication technique in a frequency hopping code division multiple access system. However, there are some difficulties in practical implementation of this technique such as synchronization of packets of different sizes and identification between regular and subpackets. This paper describes these problems and suggests practical solutions t... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Techniques for cellular networks incorporating microcells

    Publication Year: 1992, Page(s):169 - 173
    Cited by:  Papers (5)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (356 KB)

    A layered radio cell architecture is described for high capacity cellular networks, such as PCN, in which the microcells are used to increase the capacity of the system. Alternative frequency assignment schemes which support this approach are considered. A technique for handling high speed mobiles is proposed. This scheme effectively prevents handover between layers for mobiles moving too fast for... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A multipath channel model for mobile-radio communications

    Publication Year: 1992, Page(s):92 - 97
    Cited by:  Papers (3)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (384 KB)

    A model for the mobile radio channel is proposed that is intended to apply to wideband signals in the 900 MHz band. The model is specified by a two-variable impulse response hx(t), where x represents the location of the receiver. The model consists of two submodels, one describing the direct line-of-sight path, and the other the signal that reaches the receiver over simple reflections. ... View full abstract»

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