TY - GEN

T1 - New relay-based transmission protocols for wireless distributed storage systems

AU - Hollanti, Camilla

AU - Lu, Francis

AU - Karpuk, David

AU - Barreal, Amaro

PY - 2014/12/8

Y1 - 2014/12/8

N2 - Communication over a fading channel in a wireless storage system makes repair transmissions prone to physical layer errors. The repair transmission can be modeled as a multiple access channel (MAC), where multiple helpers are simultaneously communicating to the newcomer node. The existing optimal MAC space-time (ST) codes are, however, practically useless due to exponentially high decoding complexity when the number of helper nodes is big and the number of antennas at the newcomer node is low. To tackle this problem, two new repair transmission protocols based on ST-coding and relaying strategies are given in this paper. The diversity-multiplexing gain tradeoff (DMT) of the system together with sphere-decodability and low transmitter and receiver complexity in terms of the number of antennas required at each end are used as the main design criteria, thus naturally establishing a tradeoff between DMT, complexity, and the decoding delay. Both schemes are converting the MAC into a relay channel by increasing the decoding delay, which enables them to outperform the DMT of a simple time sharing protocol and the MAC DMT for certain multiplexing gains.

AB - Communication over a fading channel in a wireless storage system makes repair transmissions prone to physical layer errors. The repair transmission can be modeled as a multiple access channel (MAC), where multiple helpers are simultaneously communicating to the newcomer node. The existing optimal MAC space-time (ST) codes are, however, practically useless due to exponentially high decoding complexity when the number of helper nodes is big and the number of antennas at the newcomer node is low. To tackle this problem, two new repair transmission protocols based on ST-coding and relaying strategies are given in this paper. The diversity-multiplexing gain tradeoff (DMT) of the system together with sphere-decodability and low transmitter and receiver complexity in terms of the number of antennas required at each end are used as the main design criteria, thus naturally establishing a tradeoff between DMT, complexity, and the decoding delay. Both schemes are converting the MAC into a relay channel by increasing the decoding delay, which enables them to outperform the DMT of a simple time sharing protocol and the MAC DMT for certain multiplexing gains.

UR - http://www.scopus.com/inward/record.url?scp=84920546228&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:84920546228

T3 - Proceedings of 2014 International Symposium on Information Theory and Its Applications, ISITA 2014

SP - 585

EP - 589

BT - Proceedings of 2014 International Symposium on Information Theory and Its Applications, ISITA 2014

PB - Institute of Electrical and Electronics Engineers Inc.

T2 - 2014 International Symposium on Information Theory and Its Applications, ISITA 2014

Y2 - 26 October 2014 through 29 October 2014

ER -