Delay-Constrained Energy-Efficient Scheduling over a Multihop Link

This paper focuses on delay-constrained energy-efficient packet transmission over a static multihop link. Optimal offline scheduling (vis-a-vis total transmission energy), assuming information of all packet arrivals before scheduling, is derived. The optimal offline schedule relies on a simple delay budget allocation scheme, which allocates the delay budget to the first hop (from source to the first relaying node) as much as possible. All the relaying nodes simply perform buffer-clearing during any transmission opportunities. The total transmission energy and average packet delay are analyzed and characterized. It is demonstrated that energy savings via multihopping are possible, but depend heavily on factors such as multihop resource orthogonalization mode, delay constraints, and SNR operating regimes.