Abstract
Optimisation of average spectral efficiency for adaptive multilevel quadrature amplitude modulation (MQAM) with service outage and instantaneous bit error rate constraints is studied over fading channels with variations in two time-scales. The authors obtain the corresponding optimal schemes for power and rate adaptation based on signal-to-noise ratio for continuous and discrete rate conditions. For continuous rate MQAM they show that the optimal power allocation scheme is a combination of generalised water-filling and channel inversion. For discrete rate MQAM the optimal power will be piecewise channel inversion. The authors also show that using discrete-rate adaptation with five different rates around 1 dB power is lost compared with continuous rate adaptation scenario. In the optimisation problems, they consider block flat fading channels with Nakagami-distributed variations within each block.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
