The Capacity of Wireless Networks: Information-Theoretic and Physical Limits

• Published in: IEEE transactions on information theory Vol. 55; no. 8; pp. 3413 - 3424
• Main Authors: Franceschetti, M., Migliore, M.D., Minero, P.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-08-2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Ad hoc networks; Applied sciences; Attenuation; capacity; Channels; Detection, estimation, filtering, equalization, prediction; Exact sciences and technology; Fading; Information theory; Information, signal and communications theory; Inverse; Mathematical analysis; Mobile ad hoc networks; network information theory; Networks; Physics; scaling laws; Signal and communications theory; Signal, noise; Solid modeling; Stochastic models; Stochastic processes; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Wavelengths; Waves; Wireless communication; Wireless communications; Wireless networks; Fading channels; Fading; Stochastic model; Parameter estimation; Wireless telecommunication; wireless networks; Two dimensional model; Ad hoc networks; capacity; Scaling law; network information theory; Channel estimation; scaling laws; Wireless network; Ad hoc network; Information theory
• ISSN: 0018-9448; 1557-9654
• DOI: 10.1109/TIT.2009.2023705

It is shown that the capacity scaling of wireless networks is subject to a fundamental limitation which is independent of power attenuation and fading models. It is a degrees of freedom limitation which is due to the laws of physics. By distributing uniformly an order of n users wishing to establish pairwise independent communications at fixed wavelength inside a two-dimensional domain of size of the order of n , there are an order of n communication requests originating from the central half of the domain to its outer half. Physics dictates that the number of independent information channels across these two regions is only of the order of radicn , so the per-user information capacity must follow an inverse square-root of n law. This result shows that information-theoretic limits of wireless communication problems can be rigorously obtained without relying on stochastic fading channel models, but studying their physical geometric structure.