  This paper investigates the problem of link scheduling to meet traffic
demands with minimum airtime in a multi-transmit-receive (MTR) wireless
network. MTR networks are a new class of networks, in which each node can
simultaneously transmit to a number of other nodes, or simultaneously receive
from a number of other nodes. The MTR capability can be enabled by the use of
multiple directional antennas or multiple channels. Potentially, MTR can boost
the network capacity significantly. However, link scheduling that makes full
use of the MTR capability must be in place before this can happen. We show that
optimal link scheduling can be formulated as a linear program (LP). However,
the problem is NP-hard because we need to find all the maximal independent sets
in a graph first. We propose two computationally efficient algorithms, called
Heavy-Weight-First (HWF) and Max-Degree-First (MDF) to solve this problem.
Simulation results show that both HWF and MDF can achieve superior performance
in terms of runtime and optimality.
