Title :
Joint multi-cell processing for downlink channels with limited-capacity backhaul
Author :
Shamai, Shlomo ; Simeone, Osvaldo ; Somekh, Oren ; Poor, H. Vincent
Author_Institution :
Dept. of Electr. Eng., Technion - Israel Inst. of Technol., Haifa
fDate :
Jan. 27 2008-Feb. 1 2008
Abstract :
Multicell processing in the form of joint encoding for the downlink of a cellular system is studied under the realistic assumption that the base stations (BSs) are connected to a central unit via finite-capacity links (finite-capacity backhaul). Three scenarios are considered that present different trade-offs between global processing at the central unit and local processing at the base stations and different requirements in terms of codebook information (CI) at the BSs: 1) local encoding with CI limited to a subset of nearby BSs; 2) mixed local and central encoding with only local CI; 3) central encoding with oblivious cells (no CI). Three transmission strategies are proposed that provide achievable rates for the considered scenarios. Performance is evaluated in asymptotic regimes of interest (high backhaul capacity and extreme signal-to-noise ratio, SNR) and further corroborated by numerical results. The major finding of this work is that central encoding with oblivious cells is a very attractive option for both ease of implementation and performance, unless the application of interest requires high data rate (i.e., high SNR) and the backhaul capacity is not allowed to increase with the SNR. In this latter cases, some form of CI at the BSs becomes necessary.
Keywords :
cellular radio; channel capacity; channel coding; base station; cellular system; central unit-local processing; codebook information; downlink channel capacity; encoding; finite-capacity backhaul; global processing; joint multicell processing; transmission strategy; Base stations; Cellular networks; Character generation; Decoding; Downlink; Encoding; Message passing; Performance analysis; Signal processing; Signal to noise ratio;
Conference_Titel :
Information Theory and Applications Workshop, 2008
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4244-2670-6
DOI :
10.1109/ITA.2008.4601071