TY - JOUR
T1 - Downlink and Uplink Decoupling in Two-Tier Heterogeneous Networks with Multi- Antenna Base Stations
AU - Bacha, Mudasar
AU - Wu, Yueping
AU - Clerckx, Bruno
N1 - Funding Information:
Manuscript received March 5, 2016; revised August 29, 2016 and January 17, 2017; accepted January 23, 2017. Date of publication March 17, 2017; date of current version May 8, 2017. This work was supported by the EPSRC of U.K., under Grant EP/N015312/1. The associate editor coordinating the review of this paper and approving it for publication was C. Tepedelenlioglu.
Publisher Copyright:
© 2002-2012 IEEE.
PY - 2017/5
Y1 - 2017/5
N2 - In order to improve the uplink performance of future cellular networks, the idea to decouple the downlink (DL) and uplink (UL) association has recently been shown to provide significant gain in terms of both coverage and rate performance. However, all the works are limited to a single input single output (SISO) network. Therefore, to study the gain provided by the DL and UL decoupling in multi-antenna base stations (BSs) setup, we study a two tier heterogeneous network consisting of multi-antenna BSs, and single antenna user equipments (UEs). We use maximal ratio combining (MRC) as a linear receiver at the BSs and tools from stochastic geometry, and we derive tractable expressions for both signal-to-interference ratio (SIR) coverage probability and rate coverage probability. We observe that as the disparity in the beamforming gain of both tiers increases, the gain in terms of SIR coverage probability provided by the decoupled association over non-decoupled association decreases. We further observe that when there is asymmetry in the number of antennas of both tiers, then we need further biasing toward femto-tier on the top of decoupled association to balance the load and get optimal rate coverage probability.
AB - In order to improve the uplink performance of future cellular networks, the idea to decouple the downlink (DL) and uplink (UL) association has recently been shown to provide significant gain in terms of both coverage and rate performance. However, all the works are limited to a single input single output (SISO) network. Therefore, to study the gain provided by the DL and UL decoupling in multi-antenna base stations (BSs) setup, we study a two tier heterogeneous network consisting of multi-antenna BSs, and single antenna user equipments (UEs). We use maximal ratio combining (MRC) as a linear receiver at the BSs and tools from stochastic geometry, and we derive tractable expressions for both signal-to-interference ratio (SIR) coverage probability and rate coverage probability. We observe that as the disparity in the beamforming gain of both tiers increases, the gain in terms of SIR coverage probability provided by the decoupled association over non-decoupled association decreases. We further observe that when there is asymmetry in the number of antennas of both tiers, then we need further biasing toward femto-tier on the top of decoupled association to balance the load and get optimal rate coverage probability.
KW - Stochastic geometry
KW - heterogeneous networks
KW - maximal ratio combining
KW - multiple antennas
KW - uplink analysis
UR - http://www.scopus.com/inward/record.url?scp=85028718255&partnerID=8YFLogxK
U2 - 10.1109/TWC.2017.2665466
DO - 10.1109/TWC.2017.2665466
M3 - Article
AN - SCOPUS:85028718255
VL - 16
SP - 2760
EP - 2775
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
SN - 1536-1276
IS - 5
M1 - 7880671
ER -