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Issue 3 • Date March 2000

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Displaying Results 1 - 21 of 21
  • Field trial results for high-speed wireless indoor data communications

    Publication Year: 2000 , Page(s): 297 - 309
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (350 KB)  

    This paper reports on the development of a flexible 5-MBd equalized M-QAM testbed for high-speed wireless data communications. The unit operates in real time and was field tested in typical indoor environments. A total of 3600 independent experiments were conducted using the testbed where one of 4-, 16-, 64-QAM constellations were transmitted, and the performance as a function of adaptive equalization and antenna selection diversity was studied. The experimental results presented here help put previous simulation and analytical results into perspective and demonstrate some of the performance bounds associated with a practical implementation. The field trial results show that with only 10-mW of transmit power, reliable 10-Mbit/s data communication can take place in between rooms with a coverage radius of 17 m, and better than 15% outage at an uncoded bit error rate (BER) of 10/sup -3/. The addition of two-branch antenna selection diversity to the system would allow 10-Mbit/s transmission at better than 3% outage and 20-Mbit/s transmission at 10% outage in the same environment. Moreover, 30-Mbit/s data transmission is feasible when both the transmitter and receiver are located within the same room, albeit at higher outage levels. In general, the results demonstrate the tremendous impact that adaptive equalization can have on the achievable performance of indoor links. Average SNR was improved anywhere from 8 dB to 12 dB depending on the particular environment and data rate. The impact on the outage performance, however, was much more dramatic. View full abstract»

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  • Measurements and models for 38-GHz point-to-multipoint radiowave propagation

    Publication Year: 2000 , Page(s): 310 - 321
    Cited by:  Papers (32)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB)  

    This article presents results of a wide-band measurement campaign conducted at 38 GHz. The objective of the research was to determine multipath and time varying channel behavior of short-hop millimeter-wave point-to-multipoint radio links during various weather events. 73963 power delay profiles (PDPs) were captured on three links, each comparable to proposed local multipoint distribution systems (LMDS) in a campus environment. Multipath was observed in unobstructed LOS links during rain but not during clear weather. Short-term variation of the received signal over 1-2 min observation periods is described by a Rician distribution with a K factor which varies as a function of rain rate. Measured rain attenuation exceeds Crane's (1996) model predictions by several decibels. A novel prediction technique is presented that applies canonical antenna patterns and site specific information to estimate worst case multipath channel characteristics including relative power, time of arrival (TOA), and angle of arrival (AOA) of each multipath component. New metrics, the excess delay zone and relative power zone, are defined and contour plots are developed to determine potential reflectors from an area site map. These results and models provide useful guidelines for the design of millimeter-wave wireless communication systems. View full abstract»

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  • A microcellular ray-tracing propagation model and evaluation of its narrow-band and wide-band predictions

    Publication Year: 2000 , Page(s): 322 - 335
    Cited by:  Papers (60)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (476 KB)  

    Due to the site specific nature of microcellular operational environments, propagation models are required to take into account the exact position, orientation and electrical properties of individual buildings, and hence, ray-tracing techniques have emerged as the dominant methods to predict propagation in such environments. A novel hybrid three-dimensional (3-D) ray-tracing algorithm which can evaluate scenarios incorporating many thousands of objects by utilising the concept of "illumination zones," is presented. In order to evaluate the accuracy of the presented model, comparisons of narrow-band and wide-band predictions with measurements are performed for a variety of scenarios. First, power comparisons show that very accurate predictions can be achieved (RMS errors less than 3.7 dB). Then, wide-band analysis shows that since the RMS delay spread for systems with finite bandwidth is a function of the multipath phase, only average measured and predicted RMS delay spread values can be compared and as a result, limited averaging can produce large RMS errors. With sufficient averaging the achieved wide-band accuracy in terms of the predicted RMS delay spread, is adequate for most planning purposes. View full abstract»

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  • Prediction of multipath delay profiles in mountainous terrain

    Publication Year: 2000 , Page(s): 336 - 346
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (374 KB)  

    Measurements of the complex impulse response of 900 MHz radio channels in mountainous terrain in British Columbia, Canada, are used to quantify values for the normalized scattering cross section /spl sigma//sup 0/ for mountains covered with evergreen trees. The bistatic radar equation is then used in a propagation model to predict characteristics of the impulse response in similar terrain from topographical data. Three-dimensional (3-D) propagation models for mountainous areas are important, because such areas stress to the limit the multipath handling capabilities of most air interfaces. /spl sigma//sup 0/ is related to a more fundamental characteristic /spl gamma/ of the surface via Lambert's law. The measured value of /spl gamma/ is -21.1 /spl plusmn/2.9 dB, which is similar to some of the very few other values found in the literature. Using this value of /spl gamma/, the predicted multipath delay profiles correspond well with measurements. The results can be used to predict complex impulse responses in mountainous terrain which may be convolved with a simulated data stream to predict error rate, outage or other aspects of wireless system performance. View full abstract»

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  • Modeling the statistical time and angle of arrival characteristics of an indoor multipath channel

    Publication Year: 2000 , Page(s): 347 - 360
    Cited by:  Papers (241)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (245 KB)  

    Most previously proposed statistical models for the indoor multipath channel include only time of arrival characteristics. However, in order to use statistical models in simulating or analyzing the performance of systems employing spatial diversity combining, information about angle of arrival statistics is also required. Ideally, it would be desirable to characterize the full spare-time nature of the channel. In this paper, a system is described that was used to collect simultaneous time and angle of arrival data at 7 GHz. Data processing methods are outlined, and results obtained from data taken in two different buildings are presented. Based on the results, a model is proposed that employs the clustered "double Poisson" time-of-arrival model proposed by Saleh and Valenzuela (1987). The observed angular distribution is also clustered with uniformly distributed clusters and arrivals within clusters that have a Laplacian distribution. View full abstract»

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  • Some simple bounds on the symmetric capacity and outage probability for QAM wireless channels with Rice and Nakagami fadings

    Publication Year: 2000 , Page(s): 361 - 368
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (243 KB)  

    In this article, quickly computable upper and lower bounds are presented on the symmetric capacity of flat-faded Rice and Nakagami channels with side information (SI) for data-transmissions via finite-size quadrature amplitude modulation (QAM) constellations. The proposed bounds exhibit the appealing feature to be tight and asymptotically exact both for high and low signal-to-noise ratios (SNRs). Furthermore, exponentially tight Chernoff-like formulas are also presented for an analytical evaluation of the resulting system outage probabilities when interleaved packet transmissions are carried out. View full abstract»

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  • Random coding error exponents for flat fading channels with realistic channel estimation

    Publication Year: 2000 , Page(s): 369 - 379
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (235 KB)  

    There has been a considerable interest in determining the limits to communications over multipath fading channels. However, most studies have assumed that the channel is perfectly known at the receiver. In this paper, the random coding error exponent for flat fading channels with realistic channel state information (CSI) is studied. It is assumed that the CSI is obtained via some practical technique which utilizes a linear estimation scheme. Two commonly used techniques for channel estimation are considered in this paper, namely pilot tone extraction and pilot symbol transmission. The degradation in the achievable performance due to partial CSI is assessed and comparison of the different channel estimation methods is made. The focus of this paper is on the Jake's mobile Rayleigh flat fading model. Although Jake's model does not have a Markov property, such as that found in the commonly used exponential correlation model, which is usually attractive from the mathematical tractability point of view, Jake's model has a physical basis. Also, this model is considered herein from the standpoint of the random coding exponent. The results in this paper shed light on the amount of degradation in the achievable performance that is expected when the receiver has partial CSI. Finally, the sensitivity of the loss in achievable performance for the various channel estimation techniques with respect to channel parameters, such as Doppler spread and signal-to-noise ratio (SNR), is studied. View full abstract»

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  • A sub-burst DFT scheme for CW burst detection in mobile satellite communication

    Publication Year: 2000 , Page(s): 380 - 390
    Cited by:  Papers (2)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (333 KB)  

    This paper presents a new idea to detect a continuous-wave (CW) burst with unknown frequency using the discrete Fourier transform. Given a CW burst of certain length, an obvious detection scheme would be to compute the DFT power over the whole burst and in the given frequency bins that cover the total frequency uncertainty range. This may result in poor performance when the CW frequency is not exactly in one of the DFT bins. The new scheme divides the CW burst into L sub-bursts and computes the summation of the DFT power in each sub-burst. With very little increase on the DFT computation complexity, the overall detection performance can he greatly improved. The analysis employs a unified approach to derive the expressions of probabilities of false alarm and miss detection for both the conventional and the new schemes over the additive white Gaussian noise (AWGN) channel. Simulations are done for both the AWGN channel and the satellite fading channel. View full abstract»

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  • Decision-feedback differential detection based on linear prediction for MDPSK signals transmitted over Ricean fading channels

    Publication Year: 2000 , Page(s): 391 - 402
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (449 KB)  

    In this paper, linear prediction-based decision-feedback differential detection (DF-DD) for M-ary differential phase-shift keying (MDPSK) signals transmitted over Ricean fading channels is proposed. This scheme can improve conventional DD significantly for a multitude of frequency-nonselective channels, as shown analytically and by computer simulations. Prediction-based DF-DD is particularly well suited for application in mobile communications since the predictor coefficients may be updated regularly using the recursive least squares (RLS) algorithm. Here, adaptation can start blind, i.e., no training sequence and no a prior knowledge about the channel statistics are required. A further important characteristic of the proposed detection scheme is that no degradation occurs under frequency offset. The bit error rate (BER) performance of QDPSK with genie-aided prediction-based DF-DD is analyzed, and it is shown under which conditions the irreducible error floor of conventional DD can be removed entirely. In addition, the influence of Doppler shift is discussed. Last, the proposed scheme is compared with a second DF-DD scheme, which is based on multiple-symbol detection. View full abstract»

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  • Narrow-band interference excision in spread-spectrum systems using self-orthogonalizing transform-domain adaptive filters

    Publication Year: 2000 , Page(s): 403 - 406
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (73 KB)  

    Among many transform-domain interference excision techniques, transform-domain adaptive filtering has many advantages. It is based on a true optimization of some particular performance parameters such as the bit-error rate (BER). Moreover, it is insensitive to jammer frequency. However, transform-domain adaptive filtering also has the drawback of being incapable of tracking a rapidly changing interference because most adaptive algorithms require time to converge to the optimal solution. In this paper, a self-orthogonalizing transform-domain least mean square (SO-TRLMS) algorithm is used to speed up the convergence. Compared to a traditional transform-domain least mean square (TRLMS) algorithm, the SO-TRLMS algorithm can significantly improve the convergence rate of the LMS algorithm, thus making the transform-domain adaptive filtering technique more suitable for real-time processing. In order to show how the system performance is affected by various factors such as interference power and the transform used, this paper presents an analytical result for the BER performance that is applicable for arbitrary orthogonal linear transforms. Simulation results are also presented to demonstrate the validity of the analysis. View full abstract»

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  • Transmitter-based multiuser interference rejection for the down-link of a wireless CDMA system in a multipath environment

    Publication Year: 2000 , Page(s): 407 - 417
    Cited by:  Papers (51)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (187 KB)  

    In wireless code division multiple access (CDMA) communications systems, there has been interest in processing the transmitted down-link signal in order to shift signal processing to the transmitter where power and computational resources are plentiful, thus simplifying receiver operation and reducing the power it requires. Multiuser interference (MUI) and multipath effects observed by the receiver are anticipated and suppressed at the transmitter; channel equalization and multiuser detection are therefore not required. This paper introduces two methods that are able to combat both degradations, yet allow the receiver to remain as simple as a single user receiver for a perfect channel. For mild multipath channels, the performance of the algorithms is excellent, within a few decibels of the single user ideal channel case, at the cost of additional computation at the base station at which complete knowledge of the channels and the receiver codewords is required. One method, the decorrelating prefilter, is most flexible and applicable to existing systems yet less powerful than other previously published methods. The second, the jointly optimized sequences algorithm, has a performance on average superior to published methods. In addition to theoretical analysis and simulation of the algorithms' potential, these algorithms have also been implemented and tested on a software radio testbed and experimental data are shown. The jointly optimized sequences performed particularly well even in severe multipath and multiuser interference environments. View full abstract»

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  • Protocol-aided channel equalization in wireless ATM

    Publication Year: 2000 , Page(s): 418 - 435
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (350 KB)  

    We study the equalization problem in time division multiple access wireless asynchronous transfer mode (ATM) systems. Aiming at minimizing the overhead associated with equalization, we propose a protocol-aided channel equalization (PACE) approach for wireless ATM. Specifically, the medium access control (MAC) and data link control (DLC) protocols are exploited to provide known ATM cell headers to the receiver at the base station. A blind channel estimation-decision feedback equalizer (BCE-DFE) algorithm is developed for uplink data transmissions. There are two advantages of the BCE-DFE algorithm: the elimination of training symbols for uplink data bursts and the removal of channel estimation error propagation suffered by conventional block equalization schemes. Simulation results show the BCE-DFE has a robust performance for wireless ATM uplink data transmissions over fast time-varying channels. View full abstract»

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  • Analysis of a class of distributed asynchronous power control algorithms for cellular wireless systems

    Publication Year: 2000 , Page(s): 436 - 446
    Cited by:  Papers (33)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB)  

    In cellular wireless communication systems, uplink power control is needed to provide each mobile user with an acceptable signal to interference ratio (SIR) while simultaneously minimizing transmit power levels. We consider a class of distributed asynchronous power control algorithms based on the schemes used in IS-95 inner loop power control. Each user's received SIR is measured (using possibly outdated information) and compared to a threshold, and a single control bit is then sent to the user, indicating whether its power level should be increased or decreased. The SIR measurements and power updates do not require synchronization. We show that under certain conditions, this class of algorithms is stable and converges to a region around the optimal power assignment. We characterize this region and show that it can be made as small as desired by choosing the algorithm parameters appropriately. For an appropriate choice of algorithm parameters, we show that convergence occurs in a finite number of iterations and derive an upper bound. To illustrate our general results, we apply them to systems with fixed base station assignment, dynamic base station assignment, and macrodiversity. Finally, we give an example to illustrate the algorithm's robustness to errors in the power control commands. View full abstract»

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  • Second-order power control with asymptotically fast convergence

    Publication Year: 2000 , Page(s): 447 - 457
    Cited by:  Papers (54)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (203 KB)  

    This paper proposes a distributed power control algorithm that uses power levels of both current and previous iterations for power update. The algorithm is developed by applying the successive overrelaxation method to the power control problem. The gain from such a second-order algorithm is in faster convergence. Convergence analysis of the algorithm in case of feasible systems is provided in this paper. Using the distributed constrained power control (DCPC) as a reference algorithm, we carried out computational experiments on a DS-CDMA system. The results indicate that our algorithm significantly enhances the convergence speed of power control. A practical version of the proposed algorithm is provided and compared with the bang-bang type algorithm used in the IS-95 and the WCDMA systems. The results show that our algorithm also has a high potential for increasing the radio network capacity. Our analysis assumes that the system is feasible in the sense that we can support every active user by an optimal power control. When the system becomes infeasible because of high traffic load, it calls for other actions such as transmitter removal, which is beyond the scope of the present paper. View full abstract»

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  • Traffic improvements in wireless communication networks using antenna arrays

    Publication Year: 2000 , Page(s): 458 - 471
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB)  

    A wireless network with beamforming capabilities at the receiver is considered that allows two or more transmitters to share the same channel to communicate with the base station. A novel approach is introduced, which combines the effects of the digital signal processing (adaptive beamforming) at the physical layer with the traffic policies at the network layer on the overall queuing model of a cell. The effect of signal processing on the queuing model of the cell is represented by a parameter in the final cell model. Each cell is modeled by a multiuser/multiserver service facility, where each server is a beamformed channel formed by the cell's base station. From this effective cell model, we find the closed form solutions for blocking probabilities of the calls and total carried traffic in a wireless network with adaptive arrays. Our analytical as well as numerical results show that adaptive beamforming at the receiver reduces the blocking probability of the calls and increases the total carried traffic in the system. View full abstract»

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  • A high-capacity wireless network by quad-sector cell and interleaved channel assignment

    Publication Year: 2000 , Page(s): 472 - 480
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (279 KB)  

    We propose an improved sectorization scheme, called narrow-beam quad-sector cell (NBQC) for cellular networks, in which each cell is divided into four sectors and each sector is covered by a 60/spl deg/ antenna. The NBQC structure allows easy implementation of the concept of interleaved channel assignment (ICA), which can take full advantage of antenna directivity. With ICA, the NBQC system can enhance the system performance from several perspectives. First, the NBQC has better coverage performance than the current three-sector cellular architecture. Second, we demonstrate that in a typical radio environment, the NBQC system ran achieve a reuse cluster size N=2 with the signal-to-interference ratio (SIR) as high as 11 dB in 90% of the cell area, which is a 3-5-dB improvement over the existing cellular architectures. Third, as compared to the most advanced three-sector clover-leaf cell architecture with reuse cluster size N=3, the NBQC system with ICA can achieve reuse cluster size N=2 with very slight degradation in SIR performance, thereby still improving the system capacity by about 10% over a wide range of ninetieth percentile SIR requirements. View full abstract»

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  • A code-division switch architecture for satellite applications

    Publication Year: 2000 , Page(s): 481 - 495
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (289 KB)  

    This paper introduces a code-division methodology into switching applications. The proposed method is applied in satellite-switched code-division multiple-access (SS/CDMA) systems for routing CDMA traffic channels on board the multibeam satellites. We present code-division switch (CDS) architectures, analyze the CDS performance, and assess its complexity. The CDS has been shown to route CDMA user channels without introducing interference. The proposed CDS architecture is nonblocking, and its hardware complexity and speed are proportional to the size of the switch. We also examine the amplitude distribution of the combined signal in the CDS bus and the interference evaluation of the end-to-end link in the proposed applications. Then we consider the problem of switch control under an optimum or a random algorithm and compare its complexity with the equivalent problem in time-multiplexed switching methods. View full abstract»

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  • Performance analysis of path rerouting algorithms for handoff control in mobile ATM networks

    Publication Year: 2000 , Page(s): 496 - 509
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (283 KB)  

    This paper studies the effects of user mobility and handoff path rerouting on the traffic distributions in a mobile network environment. In mobile ATM networks, extra traffic load may be added to network links due to user mobility and handoff path rerouting. This requires higher network link capacity and possible topology reengineering in order to support the same quality of service (QoS) for mobile services. To capture the dynamic variations in mobile ATM networks, we propose to use a flow model. The model represents the mobile-generated traffic as a set of stochastic flows over a set of origin-destination (OD) pairs. The user mobility is defined by transfer probabilities of the flows and the handoff path rerouting algorithm is modeled by a transformation between the routing functions for traffic flows. The analysis shows that user mobility may cause temporal variations as well as smoothing effects on the network traffic. Using the flow network model, typical handoff path rerouting algorithms are evaluated through both analytical and experimental approaches. The evaluation methodology can be used for either redesigning the network topology for a given path rerouting algorithm or selecting a path rerouting algorithm for a given network topology under a specific mobile service scenario. View full abstract»

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  • Predictive schemes for handoff prioritization in cellular networks based on mobile positioning

    Publication Year: 2000 , Page(s): 510 - 522
    Cited by:  Papers (73)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (176 KB)  

    We propose and evaluate new schemes for channel reservation motivated by the rapidly evolving technology of mobile positioning. The schemes, called predictive channel reservation (PCR), work by sending reservation requests to neighboring cells based on extrapolating the motion of mobile stations (MSs). A number of design enhancements are incorporated to minimize the effect of false reservations and to improve the throughput of the cellular system. These enhancements include: (1) reservation pooling; (2) queuing of reservation requests; (3) hybrid approach for integrating guard channels (GCs); and (4) using a threshold distance (TD) to control the timing of reservation requests. The design enhancements have produced a set of highly efficient schemes that achieve significant reduction in handoff blocking rates while only incurring remarkably small increases in the new call blocking rates. The PCR approach has also been used to solve the MINBLOCK optimization problem and has given significant improvement over the fractional guard channel (FGC) protocol. Detailed performance results of the different variations of the PCR scheme and comparisons with conventional channel reservation schemes are presented. An analytical Markov model for the hybrid predictive version of the scheme is developed and its applicability and numerical results are discussed. View full abstract»

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  • Predictive QoS-based admission control for multiclass traffic in cellular wireless networks

    Publication Year: 2000 , Page(s): 523 - 534
    Cited by:  Papers (51)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (213 KB)  

    We develop the notion of quality of service (QoS) for multimedia traffic in terms of maximum call dropping probabilities independent of system load and a predefined call blocking probability profile for the different traffic classes for wireless networks of arbitrary shape and dimension. We describe two distributed predictive admission control algorithms, independent multiclass one-step prediction (IMOSP-CS and IMOSP-RES), which provide each traffic class with a given call dropping probability and a desired call blocking probability profile. Both algorithms may be seen as extensions of the multimedia one-step prediction (MMOSPRED) algorithm previously reported, which uses prediction of the overload probability in the home and neighbor cells in deciding whether to admit new users into a multiclass cellular system. The two algorithms differ in their approach to handoff call admission. The first algorithm completely shares the bandwidth among the entering handoff users while the second implements a partition-based reservation scheme. In this paper, we additionally impose a call blocking criterion that ensures a system-imposed call priority independent of the traffic in the system and which adapts to changes in the offered load. In comparing these algorithms to each other, we focus on system throughput and class independence. Both algorithms provide appropriate throughput under both homogeneous and heterogeneous traffic loading conditions while maintaining steady call dropping probabilities for each traffic class. View full abstract»

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  • Performance analysis of the IEEE 802.11 distributed coordination function

    Publication Year: 2000 , Page(s): 535 - 547
    Cited by:  Papers (2673)  |  Patents (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (305 KB)  

    The IEEE has standardized the 802.11 protocol for wireless local area networks. The primary medium access control (MAC) technique of 802.11 is called the distributed coordination function (DCF). The DCF is a carrier sense multiple access with collision avoidance (CSMA/CA) scheme with binary slotted exponential backoff. This paper provides a simple, but nevertheless extremely accurate, analytical model to compute the 802.11 DCF throughput, in the assumption of finite number of terminals and ideal channel conditions. The proposed analysis applies to both the packet transmission schemes employed by DCF, namely, the basic access and the RTS/CTS access mechanisms. In addition, it also applies to a combination of the two schemes, in which packets longer than a given threshold are transmitted according to the RTS/CTS mechanism. By means of the proposed model, we provide an extensive throughput performance evaluation of both access mechanisms of the 802.11 protocol. View full abstract»

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Aims & Scope

IEEE Journal on Selected Areas in Communications focuses on all telecommunications, including telephone, telegraphy, facsimile, and point-to-point television, by electromagnetic propagation.

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Editor-in-Chief
Muriel Médard
MIT