Service outage based power and rate allocation for parallel fading channels

• Published in: IEEE transactions on information theory Vol. 51; no. 7; pp. 2594 - 2611
• Main Authors: Jianghong Luo, Yates, R., Spasojevic, P.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.07.2005; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive transmission; Allocations; Boundaries; Capacity; Capacity planning; Channel capacity; Channels; Communication channels; Computational complexity; Delay; ergodic capacity; Ergodic processes; Fading; fading channel; Information theory; Optimization; outage capacity; Outages; power allocation; Power supply; Real time; Resource management; service outage; System performance; Time-varying channels; Wireless communications
• ISSN: 0018-9448; 1557-9654
• DOI: 10.1109/TIT.2005.850099

The service outage based allocation problem explores variable-rate transmission schemes and combines the concepts of ergodic capacity and outage capacity for fading channels. A service outage occurs when the transmission rate is below a given basic rate r/sub o/. The allocation problem is to maximize the expected rate subject to the average power constraint and the constraint that the outage probability is less than /spl epsi/. A general class of probabilistic power allocation schemes is considered for an M-parallel fading channel model. The optimum power allocation scheme is derived and shown to be deterministic except at channel states of a boundary set. The resulting service outage achievable rate ranges from 1-/spl epsi/ of the outage capacity up to the ergodic capacity with increasing average power. Two near-optimum schemes are also derived by exploiting the fact that the outage probability is usually small. The second near-optimum scheme significantly reduces the computational complexity of the optimum solution; moreover, it has a simple structure for the implementation of transmission of mixed real-time and non-real-time services.