TY - GEN
T1 - DoF analysis of the K-user MISO broadcast channel with hybrid CSIT
AU - Rassouli, Borzoo
AU - Hao, Chenxi
AU - Clerckx, Bruno
N1 - Publisher Copyright:
© 2015 IEEE.
PY - 2015/9/9
Y1 - 2015/9/9
N2 - We consider a K-user multiple-input single-output (MISO) broadcast channel (BC) where the channel state information (CSI) of user i(i = 1, 2,⋯, K) may be either instantaneously perfect (P), delayed (D) or not known (N) at the transmitter with probabilities λPi, λDi and λNi, respectively. In this setting, according to the three possible CSIT for each user, knowledge of the joint CSIT of the K users could have at most 3K states. Although the results by Tandon et al. show that for the symmetric two user MISO BC (i.e., λQi = λQ, ∀i ∈ {1, 2}, Q ∈ {P, D, N}), the Degrees of Freedom (DoF) region depends only on the marginal probabilities, we show that this interesting result does not hold in general when K ≥ 3. In other words, the DoF region is a function of all the joint probabilities. In this paper, given the marginal probabilities of CSIT, we derive an outer bound for the DoF region of the K-user MISO BC. Subsequently, we investigate the achievability of the outer bound in some scenarios. Finally, we show the dependence of the DoF region on the joint probabilities.
AB - We consider a K-user multiple-input single-output (MISO) broadcast channel (BC) where the channel state information (CSI) of user i(i = 1, 2,⋯, K) may be either instantaneously perfect (P), delayed (D) or not known (N) at the transmitter with probabilities λPi, λDi and λNi, respectively. In this setting, according to the three possible CSIT for each user, knowledge of the joint CSIT of the K users could have at most 3K states. Although the results by Tandon et al. show that for the symmetric two user MISO BC (i.e., λQi = λQ, ∀i ∈ {1, 2}, Q ∈ {P, D, N}), the Degrees of Freedom (DoF) region depends only on the marginal probabilities, we show that this interesting result does not hold in general when K ≥ 3. In other words, the DoF region is a function of all the joint probabilities. In this paper, given the marginal probabilities of CSIT, we derive an outer bound for the DoF region of the K-user MISO BC. Subsequently, we investigate the achievability of the outer bound in some scenarios. Finally, we show the dependence of the DoF region on the joint probabilities.
UR - http://www.scopus.com/inward/record.url?scp=84953723962&partnerID=8YFLogxK
U2 - 10.1109/ICC.2015.7248982
DO - 10.1109/ICC.2015.7248982
M3 - Conference contribution
AN - SCOPUS:84953723962
T3 - IEEE International Conference on Communications
SP - 4199
EP - 4204
BT - 2015 IEEE International Conference on Communications, ICC 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - IEEE International Conference on Communications, ICC 2015
Y2 - 8 June 2015 through 12 June 2015
ER -