Title :
On the Degrees of Freedom of K-User SISO Interference and X Channels With Delayed CSIT
Author :
Abdoli, Mohammad Javad ; Ghasemi, Abdorasoul ; Khandani, Amir K.
Author_Institution :
Huawei Technol. Canada Co., Ltd., Kanata, ON, Canada
Abstract :
The K-user single-input single-output (SISO) additive white Gaussian noise (AWGN) interference channel and 2×K SISO AWGN X channel are considered, where the transmitters have delayed channel state information (CSI) through noiseless feedback links. Multiphase transmission schemes are proposed for both channels which possess novel ingredients, namely, multiphase partial interference nulling, distributed interference management via user scheduling, and distributed higher order symbol generation. The achieved degree-of-freedom (DoF) values are greater than the best previously known DoFs for both channels with delayed CSI at the transmitters.
Keywords :
AWGN channels; interference suppression; radio links; radio transmitters; radiofrequency interference; AWGN interference channel; CSI; DoF value; K-user SISO interference; K-user single-input single-output additive white Gaussian noise channel; X channel; channel state information; degree-of-freedom value; delayed CSIT; distributed higher order symbol generation; distributed interference management; multiphase partial interference nulling; multiphase transmission scheme; noiseless feedback link; transmitter; user scheduling; Fading; Integrated circuits; Interference; MIMO; Receivers; Redundancy; Transmitters; Degrees of freedom (DoF); X channel; delayed CSIT; interference channel (IC); retrospective interference alignment (IA);
Journal_Title :
Information Theory, IEEE Transactions on
DOI :
10.1109/TIT.2013.2268154
