Mungara, Ratheesh K.George, GeordieLozano Solsona, Angel2015-04-132015-04-132014Mungara R, George G, Lozano A. Overhead and spectral efficiency of pilot-assisted interference alignment in time-selective fading channels. IEEE Transactions on Wireless Communications. 2014 Sep 08; 13(9): 4884-95. DOI 10.1109/TWC.2014.23272171536-1276http://hdl.handle.net/10230/23408The spectral efficiency achievable by IA (interfer-/nence alignment) in a/nK/n-user MIMO (multiple-input multiple-/noutput) interference channel is studied in the face of time-/nselective continuous fading explicitly estimated through pilot-/nsymbol observations. The robustness of IA in such operationally/nrelevant conditions is assessed through a joint optimization/nof the pilot overhead and the IA update interval, which are/ncharacterized—in high-power conditions—as solutions of a fixed-/npoint equation. Variations of the formulation are given for/nboth FDD (frequency-division duplexing) and TDD (time-division/nduplexing), the former requiring explicit feedback of the fading/nestimates and the latter relying on fading reciprocity. For the/nFDD variation, analog feedback is considered. In addition to/narbitrary numbers of users and antennas, and arbitrary tem-/nporal fading correlation functions, the derivations accommodate/nforward and reverse links with asymmetric power levels.application/pdfeng© 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works./nThe final published article can be found at http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6822579info:eu-repo/semantics/articlehttp://dx.doi.org/10.1109/TWC.2014.2327217Interference alignmentTime-selective fadingPilot-assisted transmissionSpectral efficiencyPilot overheadPrecoder update intervalinfo:eu-repo/semantics/openAccess