An efficient data transmission policy in an integrated voice-data ds-cdma network

CDMA schemes appear to be promising access techniques for coping with the requirements of third-generation mobile systems, mainly because of their flexibility. This paper proposes an adaptive S-ALOHA DS-CDMA access scheme as a method for integrating non-real time (i.e. Internet applications) and real-time (i.e. voice) services, by exploiting the potentials of CDMA under time-varying conditions. The adaptive component terminals autonomously change their transmission rate according to the total (voice+data) channel occupancy, so that the minimum possible data delay is almost always achieved.Peer ReviewedPostprint (published version

A survey of self organisation in future cellular networks

This article surveys the literature over the period of the last decade on the emerging field of self organisation as applied to wireless cellular communication networks. Self organisation has been extensively studied and applied in adhoc networks, wireless sensor networks and autonomic computer networks; however in the context of wireless cellular networks, this is the first attempt to put in perspective the various efforts in form of a tutorial/survey. We provide a comprehensive survey of the existing literature, projects and standards in self organising cellular networks. Additionally, we also aim to present a clear understanding of this active research area, identifying a clear taxonomy and guidelines for design of self organising mechanisms. We compare strength and weakness of existing solutions and highlight the key research areas for further development. This paper serves as a guide and a starting point for anyone willing to delve into research on self organisation in wireless cellular communication networks

Characterizing CDMA downlink feasibility via effective interference

This paper models and analyses downlink power assignment feasibility in Code Division Multiple Access (CDMA) mobile networks. By discretizing the area into small segments, the power requirements are characterized via a matrix representation that separates user and system characteristics. We obtain a closed-form analytical expression of the so-called Perron-Frobenius eigenvalue of that matrix, which provides a quick assessment of the feasibility of the power assignment for each distribution of calls over the segments. Although the obtained relation is non-linear, it basically provides an effective interference characterisation of downlink feasibility. Our results allow for a fast evaluation of outage and blocking probabilities, and enable a quick evaluation of feasibility that may be used for Call Acceptance Control. \u

Cell sleeping for energy efficiency in cellular networks: Is it viable?

An approach advocated in the recent literature for reducing energy consumption in cellular networks is to put base stations to sleep when traffic loads are low. However, several practical considerations are ignored in these studies. In this paper, we aim to raise questions on the feasibility and benefits of base station sleeping. Specifically we analyze the interference and capacity of a coverage-based energy reduction system in CDMA based cellular networks using a simple analytical model and show that sleeping may not be a feasible solution to reduce energy consumption in many scenarios. © 2012 IEEE

Adaptive schemes for packet data in a ds-cdma environment

This paper presents a novel adaptive DS-CDMA slotted-ALOHA packet random access scheme for improving the throughput of the conventional DS-CDMA slotted-ALOHA system. For this purpose a mobile-assisted algorithm is envisaged to control the change of the transmission rate according to the traffic load. This algorithm revealed that the optimum behavior may be almost reached at a low complexity cost. Moreover, the proposed algorithm was found to be robust to intercell interferencePeer ReviewedPostprint (published version