Title
Power allocation and subcarrier assignment for joint delivery of unicast and broadcast transmissions in OFDM systems.
Abstract
Most existing studies on broadcast services in orthogonal frequency division multiplexing (OFDM) systems have focused on how to allocate the transmission power to the subcarriers. However, because a broadcasting system must guarantee quality of service to all users, the performance of the broadcast service dominantly depends on the channel state of the user who has the lowest received signal-to-noise ratio among users. To reduce the effect of the worst user on the system performance, we propose a joint delivery scheme of unicast and broadcast transmissions in OFDM systems with broadcast and unicast best-effort users. In the proposed joint delivery scheme, the BS delivers the broadcast information using both the broadcast and unicast subcarriers at the same time in order to improve the performance of the broadcast service. The object of the proposed scheme is to minimize the outage probability of the broadcast service while maximizing the sum-rate of best-effort users. For the proposed joint delivery scheme, we develop an adaptive power and subcarrier allocation algorithm under the constraint of total transmission power. This paper shows that the optimal power allocation over each subcarrier in the proposed scheme has a multi-level water filling form. Because the power allocation and the subcarrier assignment problems should be jointly solved, we develop an iterative algorithm to find the optimal solution. Numerical results show that the proposed joint delivery scheme with adaptive power and subcarrier allocation outperforms the conventional scheme in terms of the outage probability of the broadcast service and the sum-rate of best-effort users.
Year
DOI
Venue
2016
10.1109/JCN.2016.000053
JOURNAL OF COMMUNICATIONS AND NETWORKS
Keywords
Field
DocType
Broadcast/multicast service,enhanced-multimedia broadcast multicast service (E-MBMS),joint delivery,orthogonal frequency division multiplexing (OFDM),resource and power allocation
Subcarrier,Multimedia Broadcast Multicast Service,Broadcasting,Computer science,Signal-to-noise ratio,Computer network,Quality of service,Unicast,Broadcast radiation,Orthogonal frequency-division multiplexing
Journal
Volume
Issue
ISSN
18
3
1229-2370
Citations 
PageRank 
References 
0
0.34
0
Authors
3
Name
Order
Citations
PageRank
DeokHui Lee121.39
Jae Woo So2115.74
Seong Ro Lee315226.32