Polynomial-time Capacity Calculation and Scheduling for Half-Duplex 1-2-1 Networks

Yahya H. Ezzeldin; Martina Cardone; Christina Fragouli; Giuseppe Caire

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arXiv · 1901.02933

Polynomial-time Capacity Calculation and Scheduling for Half-Duplex 1-2-1 Networks

Yahya H. Ezzeldin·Martina Cardone·Christina Fragouli·Giuseppe Caire

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Abstract

This paper studies the 1-2-1 half-duplex network model, where two half-duplex nodes can communicate only if they point `beams' at each other; otherwise, no signal can be exchanged or interference can be generated. The main result of this paper is the design of two polynomial-time algorithms that: (i) compute the approximate capacity of the 1-2-1 half-duplex network and, (ii) find the network schedule optimal for the approximate capacity. The paper starts by expressing the approximate capacity as a linear program with an exponential number of constraints. A core technical component consists of building a polynomial-time separation oracle for this linear program, by using algorithmic tools such as perfect matching polytopes and Gomory-Hu trees.

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Yahya H. Ezzeldin, Martina Cardone, Christina Fragouli, Giuseppe Caire. 2019-01-09. Polynomial-time Capacity Calculation and Scheduling for Half-Duplex 1-2-1 Networks. https://arxiv.org/abs/1901.02933

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