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Vehicular Technology, IEEE Transactions on

Issue 2 • Date May 1998

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Displaying Results 1 - 25 of 32
  • Mobility of queued call requests of a new call-queueing technique for cellular systems

    Publication Year: 1998 , Page(s): 480 - 488
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (340 KB)  

    A queueing algorithm for new call requests has been proposed to increase the system capacity of traditional fixed channel allocation (FCA) handoff channel reservation schemes. However, mobility of queued call requests was ignored in previous literature. In this paper, a detailed analysis on the effects of the mobility of queued call requests is included in the analytic model. This is important because we found that the mobiles with queued call requests are very likely to leave the cell before granted a free channel. Computer simulation is performed and the results are compared with the numerical ones. It is found that the mobility of the queued new call requests reduces the average queueing delay, but increases blocking probability generally. View full abstract»

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  • Hypergraph models for cellular mobile communication systems

    Publication Year: 1998 , Page(s): 460 - 471
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB)  

    Cellular systems have hitherto been modeled mostly by graphs for the purpose of channel assignment. However, hypergraph modeling of cellular systems offers a significant advantage over graph modeling in terms of the total traffic carried by the system. For example, we show that a 37-cell system when modeled by a hypergraph carries around 30% more traffic than when modeled by a graph. We study the performance of channelized cellular systems modeled by hypergraphs in comparison with those modeled by graphs. For this purpose, we have evaluated the capacities of these cellular networks defined in McEliece and Sivarajan (1994). Evaluation of the capacity necessitates generation of maximal independent sets of hypergraphs. We describe some new algorithms that we have developed for this purpose View full abstract»

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  • On channel estimation and sequence detection of interleaved coded signals over frequency nonselective Rayleigh fading channels

    Publication Year: 1998 , Page(s): 558 - 565
    Cited by:  Papers (10)  |  Patents (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (220 KB)  

    Due to the receiver complexity introduced by interleaving, the implementation of maximum likelihood (IML) decoding of interleaved coded signals transmitted over frequency nonselective Rayleigh fading channels has been shown to be practically impossible. As an alternative, a two-stage receiver structure has been proposed, where the channel estimation and sequence decoding are done separately. The channel estimation issue in a two-stage receiver is examined in detail in this paper. It is shown that although an optimum (maximum a posteriori (MAP)) channel estimation is not possible in practice, it can be approached asymptotically by joint MAP estimation of the channel and the coded data sequence. The implementation of the joint MAP estimation is shown to be an ML sequence estimator followed by an minimum mean-square error (MMSE) channel estimator. Approximate fill sequence estimation using pilot symbol interpolation is also studied, and through computer simulations, its performance is compared to receivers using hit sequence estimation. The effect of decision delay (DD), prediction order, and pilot insertion rate (PIR) on the reduced complexity ML sequence estimation is investigated as well. Finally, a practical receiver is proposed that makes the best compromise among the error performance, receiver complexity, DD, and power (or bandwidth) expansion due to pilot insertion View full abstract»

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  • Cumulant-based adaptive multichannel filtering for wireless communication systems with multipath RF propagation using antenna arrays

    Publication Year: 1998 , Page(s): 377 - 391
    Cited by:  Papers (12)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (648 KB)  

    A method based on high-order statistics is proposed to mitigate the performance degradation caused by multipath RF propagation in a mobile radio communication system using a linear antenna array at the base-station receiver. It is shown that an overdetermined system of linear equations (involving only cumulants of the received baseband digitized signal) can be obtained to perform noniterative deconvolution. An efficient adaptive algorithm based on square-root decomposition is proposed to avoid numerical problems when real-time tracking of moving transmitters is needed View full abstract»

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  • Quotient coding for fading channels

    Publication Year: 1998 , Page(s): 499 - 505
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (216 KB)  

    Multiplicative Rayleigh fading is a frequent problem in wireless communications. If the channel is relatively benign and fading is not severe, one may obtain higher bit rates for an equivalent bandwidth by using M-ary QAM modulation (MQAM). A variation, used to combat channel fading while still retaining MQAM, is differential MQAM (i.e., DQAM). The term differential refers to the phase which is coded exactly as in DPSK, however, the amplitude is still subject to distortion by the fading channel. In this paper, we propose a technique called quotient coding, which is designed to remove channel effects from the symbol amplitude as well as its phase. In particular, we shall apply it to MQAM resulting in modulation which we term QQAM. In contrast to DQAM, QQAM is just as effective at suppressing the effects of channel fading with respect to the entire symbol as DPSK is for the phase alone. In fact, the scaling of the amplitude at the receiver is entirely irrelevant to QQAM View full abstract»

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  • Subscriber location in CDMA cellular networks

    Publication Year: 1998 , Page(s): 406 - 416
    Cited by:  Papers (187)  |  Patents (48)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (264 KB)  

    Subscriber radio location techniques are investigated for code-division multiple-access (CDMA) cellular networks. Two methods are considered for radio location: measured times of arrival (ToA) and angles of arrival (AoA). The ToA measurements are obtained from the code tracking loop in the CDMA receiver, and the AoA measurements at a base station (BS) are assumed to be made with an antenna array. The performance of the two methods is evaluated for both ranging and two-dimensional (2-D) location, while varying the propagation conditions and the number of BS's used for the location estimate View full abstract»

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  • An efficient borrowing channel assignment scheme for cellular mobile systems

    Publication Year: 1998 , Page(s): 602 - 608
    Cited by:  Papers (23)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (164 KB)  

    In this paper, we propose a new efficient borrowing channel assignment (BCA) scheme, which consists of two phases. The first ordinary channel allocation phase borrows a channel from neighboring cells by an impact-based borrowing strategy. The second channel reallocation phase has a reallocation procedure for locked-channel utilization and a reallocation procedure for efficient channel reuse. Simulation results show that in both uniform and nonuniform traffic cases, our schemes significantly reduce the system blocking probability over the other existing schemes. Furthermore, one of our schemes has a much smaller number of reallocations than other compared schemes View full abstract»

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  • Performance of an S-CDMA system with noncoherent spread-spectrum MSK modems

    Publication Year: 1998 , Page(s): 591 - 601
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (548 KB)  

    Simplified noncoherent and differentially coherent spread-spectrum (SS) minimum shift keying (MSK) receiver structures are presented. It is shown that an optimal noncoherent SS receiver for pure (with rectangular baseband pulses) offset QPSK signals can serve as a suboptimal (performance loss ≃0.9 dB) noncoherent receiver for SS MSK signals. The conditions of orthogonality of SS MSK signals are derived in synchronous and quasi-synchronous code-division multiple-access (CDMA) systems. Computer simulation results evaluate the performance of the CDMA system with suggested receivers under certain conditions View full abstract»

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  • Performance of trellis-coded direct-sequence spread spectrum with noncoherent reception in a fading environment

    Publication Year: 1998 , Page(s): 579 - 590
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (628 KB)  

    In this paper, we consider the performance of different coding schemes for direct-sequence spread spectrum (DS-SS) in a nonselective Rician faded channel. The Nordstrom-Robinson (NR) code, a nonlinear code that has a large distance for a given rate combined with a trellis code, is examined. A bound is developed on the error probability for this trellis-coded NR (TCNR) code with noncoherent reception over a frequency-nonselective Rayleigh or Rician fading channel with additive white Gaussian noise (AWGN). This bound is tighter than the standard union bound. Our results indicate that the standard union bound can be significantly different from the more accurate results obtained from the improved union bound. In addition, there is a considerable coding gain at high signal-to-noise ratio (SNR) for the TCNR code over the conventional DS-SS code at the same data rate View full abstract»

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  • An extended Suzuki model for land mobile satellite channels and its statistical properties

    Publication Year: 1998 , Page(s): 617 - 630
    Cited by:  Papers (53)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (648 KB)  

    This paper deals with the statistical characterization of a stochastic process which is a product of a Rice and lognormal process. Thereby, we consider the more general case where the two Gaussian noise processes describing the Rice process are correlated. The resulting process are named as extended Suzuki process, which can be used as a suitable statistical model for describing the fading behavior of large classes of frequency nonselective land mobile satellite channels. In particular, the statistical properties (e.g., probability density function (pdf) of amplitude and phase, level-crossing rate, and average duration of fades) of the Rice process with cross-correlated components as well as of the proposed extended Suzuki process are investigated. Moreover, all statistical model parameters are optimized numerically to fit the cumulative distribution function and the level-crossing rate of the underlying analytical model to measured data collected in different environments. Finally, an efficient simulation model is presented which is in excellent conformity with the proposed analytical model View full abstract»

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  • CDMA cellular systems performance with fading, shadowing, and imperfect power control

    Publication Year: 1998 , Page(s): 450 - 459
    Cited by:  Papers (47)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (392 KB)  

    This paper addresses capacity estimation for cellular code-division multiple-access (CDMA) systems, assuming the IS-95 standard as a reference. Extending a previous analytical method (Viterbi et al., 1994), we obtain a sequence of bounds on capacity, and then we introduce an accurate approximation to reduce computation complexity. The analysis accounts for interference internal and external to the reference cell, fading, shadowing, and imperfect power control. Outage probability is expressed in terms of the characteristic functions (cf's) of the interference and imperfect power control random variables (RV's). The interference contributions are computed on the basis of a Poisson distribution for the number of users in a lognormally shadowed channel. Results are provided for different channel conditions and are validated against Monte Carlo simulations. A comparison against previously published CDMA capacity estimates is carried out, aimed at clarifying some controversial issues. It is also confirmed that large system capacity is achievable under tight power control View full abstract»

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  • An algorithm for short-block data detection in the near-to-Toeplitz case

    Publication Year: 1998 , Page(s): 566 - 578
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (444 KB)  

    Crozier et al. (1990, 1992) have developed schemes for estimating transmitted data on a block-by-block rather than symbol-by-symbol basis. In general, this requires the solution of a linear system of equations with a near-to-Toeplitz structure. In this paper, we apply the algorithm of Cybenko and Berry (1990) for the efficient solution of near-to-Toeplitz linear systems of equations to the data detection problem of Crozier et al. The algorithm of Cybenko and Berry is based upon the use of hyperbolic Householder transformations and is asymptotically more efficient in terms of the number of operations than a direct method of solution based, say, upon the use of a general Cholesky linear system solver. Because near-to-Toeplitz matrices can be very ill conditioned, even when the matrix is small, the application of Bischof's (1990) incremental condition estimator (ICE) algorithm is shown to be useful in detecting such ill conditioning View full abstract»

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  • Improving the capacity in wireless networks through integrated channel base station and power assignment

    Publication Year: 1998 , Page(s): 417 - 427
    Cited by:  Papers (20)  |  Patents (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (236 KB)  

    The limited availability of radio frequency spectrum will require future wireless systems to use more efficient and sophisticated resource allocation methods to increase network capacity. In this work, we propose a joint resource allocation algorithm (JRAA) that makes the channel base station and power assignment in a wireless network with an arbitrary number of base stations and mobiles attempting to minimize the number of channels needed to provide each user in the system with an acceptable radio connection. We compare the performance of the JRAA for both the forward (downstream) and reverse (upstream) directions, in terms of the achievable traffic capacity, with some bounds on the performance of the maximum packing (MP), clique packing (CP), and reuse partitioning (RP) techniques, which are usually used as benchmarks on the capacity that can be achieved by any traffic-adaptive dynamic channel assignment strategy, where the quality is guaranteed by the reuse distance. Those performance results verify the improvement that can be achieved by the integration of the channel base station and power assignment. Finally, several versions of the two-way channel assignment problem are studied and evaluated View full abstract»

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  • Performance evaluation and application of channel offset schemes in indoor channel assignments

    Publication Year: 1998 , Page(s): 609 - 616
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB)  

    We deal with channel offset schemes and their application in three-dimensional (3-D) frequency reuse environments with ideal cubic microcells. Formulas are derived to calculate channel reuse distances (CRDs) and interchannel usage distances (IUDs) for a given offset degree. For an indoor personal communication network (PCN), an algorithm is proposed for fixed channel assignment with channel offset. The spectral efficiency of channel offset schemes is discussed and the results show that compared to the channel offsetless scheme, channel offset schemes make more efficient use of limited spectrum resources View full abstract»

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  • Space diversity antenna arrangements mounted on a metal pole for illuminating a street cell

    Publication Year: 1998 , Page(s): 531 - 536
    Cited by:  Papers (3)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (136 KB)  

    Two-branch vertical space diversity (V-SD) and horizontal space diversity (H-SD) antenna arrangements mounted on a metal pole to illuminate a street cell are investigated. Measurement results taken in a Japanese suburban area are also presented. These results clarify the required arrangements for both V-SD and H-SD configurations. Measured results show that the optimum arrangement of the H-SD configuration depends on the diameter of the pole on which the antennas are mounted View full abstract»

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  • A simple analytical framework for location management in personal communication systems

    Publication Year: 1998 , Page(s): 428 - 439
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (260 KB)  

    Efficient mobility management for portable stations (PS's)-handoff, channel assignment and locating-will play an important role in future personal communication systems (PCS's). Among these tasks, location management plays a critical role for wide-area roaming. The key elements of locating are location registration/updating and paging. Due to the smaller cell size in PCS, the high boundary crossing rate of PS will result in more frequent location area (LA) updating. This, in turn, will result in more interrogations with location registers, which will generate a higher volume of access and signaling traffic (SS7 traffic). One solution to this problem is to increase the size of LA, which, unfortunately, also increases paging traffic. Efficient paging algorithms may generate relatively less paging traffic such that larger LA's may become plausible. Depending on the call-arrival rate to the cell, boundary crossing rate, optimum size of LA, and paging technique used, the overall cost could vary substantially. The paging techniques considered in this paper are simultaneous paging and sequential paging. The two schemes are studied in detail in order to understand the problems associated with location management in the PCS environment. In the authors' opinion, this paper provides, for the first time, a simple yet powerful analytical framework which can be used to analyze “intelligent” paging schemes as well as simultaneous and sequential paging View full abstract»

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  • A transportable neural-network approach to autonomous vehicle following

    Publication Year: 1998 , Page(s): 694 - 702
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (216 KB)  

    This paper presents the development and testing of a neural-network module for autonomous vehicle following. Autonomous vehicle following is defined as a vehicle changing its own steering and speed while following a lead vehicle. The strength of the developed controller is that no characterization of the vehicle dynamics is needed to achieve autonomous operation. As a result, it can be transported to any vehicle regardless of the nonlinear and often unobservable dynamics. Data for the range and heading angle of the lead vehicle were collected for various paths while a human driver performed the vehicle following control function. The data was collected for different driving maneuvers including straight paths, lane changing, and right/left turns. Two time-delay backpropagation neural networks were then trained based on the data collected under manual control-one network for speed control and the other for steering control. After training, live vehicle following runs were done under the neural-network control. The results obtained indicate that it is feasible to employ neural networks to perform autonomous vehicle following View full abstract»

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  • Video camera method for moving-vehicle location

    Publication Year: 1998 , Page(s): 686 - 693
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (148 KB)  

    A method has been developed for determining vehicle coordinates (position, yaw, pitch and roll) during test track runs of light vehicles subjected to large roll maneuvers. This procedure is based on the fact that if three prominent features on the vehicle, such as outrigger corners, are recorded simultaneously and matched with two synchronized video cameras, all six coordinates are uniquely determined. Details of the method are presented along with results from two different methods of verification View full abstract»

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  • On the minimization of overhead in channel impulse response measurement

    Publication Year: 1998 , Page(s): 631 - 636
    Cited by:  Papers (2)  |  Patents (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (260 KB)  

    This paper presents a new method for channel impulse response measurement with a suitably designed binary sounding sequence. This method minimizes the system overhead and results in ideal channel estimation using three correlators instead of one. This system complexity can be easily overcome by the present technologies. The class of sounding sequences used in this method is the training sequence for channel impulse response measurement with the zero values of the autocorrelation function at all shifts except zero and middle shifts in European digital cellular mobile telephone systems based on the global system for mobile communication (GSM). Computer searches are carried out to find the suitable sounding sequences View full abstract»

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  • Analysis of a CDMA soft-handoff algorithm

    Publication Year: 1998 , Page(s): 710 - 714
    Cited by:  Papers (34)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (148 KB)  

    This paper analyzes the performance of a soft-handoff algorithm of the type that has been proposed in IS-95 for a code-division multiple access (CDMA) system. While the analysis is stimulated by IS-95, the focus is more on developing applicable analysis methodology rather than on specifically modeling the present IS-95 algorithm. In the soft-handoff scheme, multiple base stations are involved in the communication to and from one mobile station to improve the handoff performance on the boundaries between two base stations by providing channel diversity. On the other hand, there are additional resources used during soft-handoff. There is, thus, a tradeoff between diversity advantage and resource utilization. The analysis provides quantification for this tradeoff. The analysis is validated with simulation. The analytical results can be used to gain insight and help select the appropriate handoff thresholds View full abstract»

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  • Mobility and traffic analyses in three-dimensional PCS environments

    Publication Year: 1998 , Page(s): 537 - 545
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB)  

    We need to solve various mobility/traffic problems in one-dimensional (1-D), two-dimensional (2-D), and three-dimensional (3-D) micro or picocell environments to efficiently plan future personal communications services (PCS). However, mobility/traffic problems have thus far primarily been studied in 1-D and 2-D cell structures. We extend the previous mobility modeling from 1-D or 2-D space to 3-D unbounded indoor building environments having staircase regions by analytically modeling the mobility to estimate the number of handoffs. We also characterize the blocking probability of each cell according to the mobility by predicting the equivalent input traffic per cell. Based on the blocking probability model, we obtain the required number of channels per cell under the given blocking probability constraint. For example, 13 channels per cell are required to be assigned in order to meet the requirement that the blocking probability does not exceed 0.02 in the case where the number of radio ports (RPs) (cells) is four and 180 users are moving with a mean velocity of 2 km/h (horizontal motion) and 2/3 km/h (vertical motion) on each floor. The computer simulation results are also close to the analytical ones. These results can be utilized in the network planning of future PCS View full abstract»

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  • Modeling of the handover dwell time in cellular mobile communications systems

    Publication Year: 1998 , Page(s): 489 - 498
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB)  

    Handover request queueing has been extensively analyzed as a handover protection scheme for future cellular networks. In this frame, however, while channel holding time distribution and cell boundary crossing rate have been modeled, the distribution of the allowed queue waiting time-i.e., the handover dwell time-has remained an open question from the modeling standpoint. In this frame, this paper proposes a model of the handover dwell time in circular cells' coverage. The agreement between modeling and simulation results is very satisfactory. A fitting of an asymptotic behavior of the handover dwell-time distribution with a truncated Gaussian function is also provided, measuring the fitting goodness in various test cases. The practical insights the model can provide are also outlined in the paper View full abstract»

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  • Rain attenuation statistics useful for the design of mobile satellite communication systems

    Publication Year: 1998 , Page(s): 637 - 648
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (268 KB)  

    We have investigated how rain attenuation statistics, necessary to design fixed satellite systems working at frequencies greater than 10 GHz, are transformed to those applicable to the design of mobile satellite systems working in the same frequency bands and weather conditions in the special case of vehicles driven in zig-zag patterns to simulate city streets. The vehicles' speed has been modeled as a lognormal random variable, a mathematical model derived from measurements performed in freeways or in city traffic. We have used a large number of rain-rate time series collected in Italy (Gera Lario and Fucino) and in Canada (Montreal) to simulate rain-rate spatial fields and radio links at 19.77 GHz along a 30.6° slant path. The simulations have shown that a receiving or transmitting terminal moving in zig-zag patterns may experience, in the long term and for a given attenuation, a smaller outage probability, compared to the fixed terminal. For a given rain attenuation, the ratio between the outage probability of the mobile system and that of the fixed system (probability extrapolation factor ξ) is estimated to be around 0.2-0.3 in the optimistic case in which the probability of encountering rain is the same for all observers (fixed or in motion)-a less optimistic estimate shows that the probability of encountering rain might be twice as large and that, as a consequence, the values of ξ mentioned must be doubled. Conservative values of ξ can be calculated by using average values of rain storm speed and vehicles and average distances covered in the rain by fixed and mobile terminals. The results are less sensitive to changes in the geometrical or other parameters of the simulations View full abstract»

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  • Fairness in wireless microcellular networks

    Publication Year: 1998 , Page(s): 472 - 479
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB)  

    In the design of cellular and microcellular telecommunication networks, it is common to consider service to subscribers in specific regions by more than a single base station. Although the service overlap provides certain advantages, such as performance improvement achieved in dynamic channel assignment, it results in a large variance in the quality of service across the cells. In this paper, we introduce channel restriction to achieve fairness in the network quality of service. We develop analytical and simulation models for network performance and examine the advantages gained in increased system throughput and reduced probability of handover failure. The numerical results indicate that restricting the number of available channels to users in the overlap region results in considerable improvement in the carried traffic and mean probability of blocking. Finally, we discuss the possibility of substituting or scaling down the guard channels with channel restriction to achieve the desired effect of reduced forced termination View full abstract»

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  • Analysis of course errors on CVOR antennas (including effects of mutual coupling between elements)

    Publication Year: 1998 , Page(s): 392 - 405
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (428 KB)  

    A VHF omnidirectional radio range (VOR) is a navigation aid radio beacon facility, which provides aircraft with azimuth information relative to the VOR station in question as the origin. In Japan, two types of VOR-the conventional type (referred to as a CVOR) and the Doppler type (referred to as a DVOR)-are currently in use. An element known as the Alford loop antenna (ALA), which changes the loading reactance, is used for the VOR because the horizontally polarized wave and nondirectivity in the horizontal plane are preferred. A VOR antenna consists of a carrier antenna and a sideband antenna-an aircraft receives separate signals from these two antennas and compares them to obtain azimuth information. The mutual coupling between the elements forming the carrier and the sideband antenna affects the directivity of the single elements, resulting in errors in azimuth information. With the mutual coupling between the antenna elements being taken into consideration, a quantitative calculation was made by using the moment method-the results of the calculation made it clear that a loading reactance value of -320 Ω is better to make not mutually coupled elements nondirectional while a loading reactance value of -600 Ω is optimum to minimize the azimuth error of a CVOR View full abstract»

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Aims & Scope

IEEE Transactions on Vehicular Technology covers land, airborne, and maritime mobile services, vehicular electrotechnology, equipment, and systems identified with the automotive industry.

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Meet Our Editors

Editor-in-Chief
Yuguang Michael Fang
University of Florida