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Fumiyuki Adachi - One of the best experts on this subject based on the ideXlab platform.

  • Impact of Shadowing Correlation on Reverse Link Capacity of DS-CDMA Cellular System
    IEICE Transactions on Communications, 2006
    Co-Authors: Arif Junaidi, Eisuke Kudoh, Fumiyuki Adachi
    Abstract:

    Independent shadowing losses are often assumed for evaluating the Link Capacity of direct sequence code division multiple access (DS-CDMA) cellular system. However, shadowing losses may be partially correlated since the obstacles surrounding a mobile station block similarly the desired signal and the interfering signals. In this letter, we discuss how the shadowing correlation impacts the reverse Link Capacity of a power-controlled DS-CDMA cellular system, by numerical analysis.

  • theoretical analysis of reverse Link Capacity for an sir based power controlled cellular cdma system in a multipath fading environment
    IEEE Transactions on Vehicular Technology, 2001
    Co-Authors: Duk Kyung Kim, Fumiyuki Adachi
    Abstract:

    Capacity estimation in a code-division multiple-access system is closely related to power control schemes, which complicates the analysis due to the interaction between the signal power and the interference from other users and from other paths. For a signal-to-interference ratio (SIR)-based power control scheme, most previous work has been restricted to a single-cell system or to a multiple-cell system neglecting the effect of multipath fading. This paper is to give a theoretical foundation to the possible reverse Link Capacity of a multiple-cell system with perfect SIR-based power control, assuming two different multipath Rayleigh fading channel models: uniform and exponential power delay profiles. The effects of the numbers of resolvable propagation paths and RAKE fingers, and other system parameters such as the required E/sub b//I/sub 0/, the processing gain, and the maximum allowable transmit power of a mobile station, are investigated. The results are compared between single- and multiple-cell systems. When the number of resolvable paths is one or the number of Rake fingers is one, the Link Capacity becomes zero in a multiple-cell environment. This can be avoided by the use of antenna diversity. Antenna diversity reception is found to linearly increase the Link Capacity as the number of antennas increases.

Brenda Cheang - One of the best experts on this subject based on the ideXlab platform.

  • an investigation into the vehicle routing problem with time windows and Link Capacity constraints
    Omega-international Journal of Management Science, 2012
    Co-Authors: Brenda Cheang, Andrew Lim, Lei Zhang, Yi Zhu
    Abstract:

    Abstract In this work, we investigate a new, yet practical, variant of the vehicle routing problem called the vehicle routing problem with time windows and Link Capacity constraints (VRPTWLC). The problem considers new constraints imposed on road Links with regard to vehicle passing tonnage, which is motivated by a business project with a Hong Kong transportation company that transports hazardous materials (hazmats) across the city and between Hong Kong and mainland China. In order to solve this computationally challenging problem, we develop a tabu search heuristic with an adaptive penalty mechanism (TSAP) to help manage the company's vehicle fleet. A new data set and its generation scheme are also presented to help validate our solutions. Extensive computational experiments are conducted, showing the effectiveness of the proposed solution approach.

Yi Zhu - One of the best experts on this subject based on the ideXlab platform.

  • an investigation into the vehicle routing problem with time windows and Link Capacity constraints
    Omega-international Journal of Management Science, 2012
    Co-Authors: Brenda Cheang, Andrew Lim, Lei Zhang, Yi Zhu
    Abstract:

    Abstract In this work, we investigate a new, yet practical, variant of the vehicle routing problem called the vehicle routing problem with time windows and Link Capacity constraints (VRPTWLC). The problem considers new constraints imposed on road Links with regard to vehicle passing tonnage, which is motivated by a business project with a Hong Kong transportation company that transports hazardous materials (hazmats) across the city and between Hong Kong and mainland China. In order to solve this computationally challenging problem, we develop a tabu search heuristic with an adaptive penalty mechanism (TSAP) to help manage the company's vehicle fleet. A new data set and its generation scheme are also presented to help validate our solutions. Extensive computational experiments are conducted, showing the effectiveness of the proposed solution approach.

P.t. Mathiopoulos - One of the best experts on this subject based on the ideXlab platform.

  • Reverse Link Capacity analysis of cellular CDMA systems with controlled power disparities and successive interference cancellation
    IEEE Transactions on Wireless Communications, 2006
    Co-Authors: Hong Nie, P.t. Mathiopoulos, George K. Karagiannidis
    Abstract:

    This paper presents a new approach in analyzing the reverse Link Capacity performance of cellular CDMA systems employing successive interference cancellation (SIC). Due to the controlled power disparity present in such systems previous methods cannot precisely model their inter-cell interference. We first introduce a novel model which allows the accurate analysis and evaluation of the inter-cell interference of cellular CDMA systems with controlled power disparity. Its validity is verified by means of theoretical analysis and computer simulations. Secondly, by using this new inter-cell interference model, a theoretical analysis of the CDMA reverse Link Capacity is presented. In terms of evaluation results, we focus on the performance improvements SIC offers as compared to single user detection (SUD). Analytical results complemented by equivalent computer simulated performance evaluation results have shown that SIC significantly increases the reverse Link Capacity of cellular CDMA systems operating in realistic controlled power disparity environments

  • Reverse Link Capacity analysis for cellular CDMA systems employing combining macrodiversity
    International Conference on Communication Technology Proceedings 2003. ICCT 2003., 1
    Co-Authors: Hong Nie, P.t. Mathiopoulos
    Abstract:

    In the open technical literature, all the papers investigating the reverse Link Capacity of the combining macrodiversity simplified their analysis by assuming that the radio signals received by all the base stations in the cellular CDMA system are combined to detect mobile users. Therefore, their analysis results are actually an upper bound of the real reverse Link Capacity. In this paper, by assuming that only the radio signals received by the base stations in the vicinity of the mobile user are combined to detect the mobile user, we have theoretically analyzed the reverse Link Capacity of cellular CDMA systems employing the combining macrodiversity. Furthermore, by taking a pedestrian application in cdma2000 as an example, computer simulations are performed, and the obtained simulation results have confirmed our theoretical analysis.

  • VTC Spring - Analysis of Reverse Link Capacity for Cellular CDMA Systems Employing Group Successive Interference Cancellation
    2006 IEEE 63rd Vehicular Technology Conference, 1
    Co-Authors: A.-m. Silvester, Robert Schober, P.t. Mathiopoulos
    Abstract:

    The reverse Link Capacity of a cellular code division multiple access (CDMA) network employing group successive interference cancellation (GSIC) is studied. By extending a model previously applied to successive interference cancellation (SIC), we analytically evaluate the outage performance of GSIC. Numerical and simulation results demonstrate that without a large reduction in reverse Link Capacity the GSIC scheme can significantly reduce detection delay and hardware complexity as compared to conventional SIC.

Andrew Lim - One of the best experts on this subject based on the ideXlab platform.

  • an investigation into the vehicle routing problem with time windows and Link Capacity constraints
    Omega-international Journal of Management Science, 2012
    Co-Authors: Brenda Cheang, Andrew Lim, Lei Zhang, Yi Zhu
    Abstract:

    Abstract In this work, we investigate a new, yet practical, variant of the vehicle routing problem called the vehicle routing problem with time windows and Link Capacity constraints (VRPTWLC). The problem considers new constraints imposed on road Links with regard to vehicle passing tonnage, which is motivated by a business project with a Hong Kong transportation company that transports hazardous materials (hazmats) across the city and between Hong Kong and mainland China. In order to solve this computationally challenging problem, we develop a tabu search heuristic with an adaptive penalty mechanism (TSAP) to help manage the company's vehicle fleet. A new data set and its generation scheme are also presented to help validate our solutions. Extensive computational experiments are conducted, showing the effectiveness of the proposed solution approach.