TY - GEN
T1 - Instantaneous degrees of freedom of downlink interference channels with multiuser diversity
AU - Kim, Taejoon
AU - Love, David J.
AU - Clerckx, Bruno
PY - 2011
Y1 - 2011
N2 - Independent channel fading across different users in a wireless network enables the system to exploit multiuser diversity. In this paper, we investigate the impact of user scheduling on the instantaneous degrees of freedom of multiple interfering cellular networks. Particularly, we consider a homogeneous multiple cellular downlink scenario with multiple users per cell. We show that if the number of users in a cell scales faster than linearly with SNR, the instantaneous degrees of freedom with multiuser diversity increases and converges to L in both mean-square (m.s.) sense and almost sure (a.s.) sense for an L-cell downlink interference channel, even though very limited channel feedback is needed. Each user is equipped with L-1 antennas to capture the multidimensional out-of-cell interference from other base stations, while the base station has a single antenna. The user scheduling strategy that achieves L instantaneous degrees of freedom is to poll users experiencing only a small amount of out-of-cell interference. The instantaneous degrees of freedom with multiuser diversity and its convergence mode are compared to those of conventional interference alignment. Furthermore, the user scaling law is relaxed when ergodic throughout is analyzed.
AB - Independent channel fading across different users in a wireless network enables the system to exploit multiuser diversity. In this paper, we investigate the impact of user scheduling on the instantaneous degrees of freedom of multiple interfering cellular networks. Particularly, we consider a homogeneous multiple cellular downlink scenario with multiple users per cell. We show that if the number of users in a cell scales faster than linearly with SNR, the instantaneous degrees of freedom with multiuser diversity increases and converges to L in both mean-square (m.s.) sense and almost sure (a.s.) sense for an L-cell downlink interference channel, even though very limited channel feedback is needed. Each user is equipped with L-1 antennas to capture the multidimensional out-of-cell interference from other base stations, while the base station has a single antenna. The user scheduling strategy that achieves L instantaneous degrees of freedom is to poll users experiencing only a small amount of out-of-cell interference. The instantaneous degrees of freedom with multiuser diversity and its convergence mode are compared to those of conventional interference alignment. Furthermore, the user scaling law is relaxed when ergodic throughout is analyzed.
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U2 - 10.1109/ACSSC.2011.6190225
DO - 10.1109/ACSSC.2011.6190225
M3 - Conference contribution
AN - SCOPUS:84861321817
SN - 9781467303231
T3 - Conference Record - Asilomar Conference on Signals, Systems and Computers
SP - 1293
EP - 1297
BT - Conference Record of the 45th Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2011
T2 - 45th Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2011
Y2 - 6 November 2011 through 9 November 2011
ER -