Ad Hoc mmWave Systems
Ad hoc networks provide a flexible, infrastructure-free means to communicate between soldiers in war zones, aid workers in disaster areas, or consumers in device-to-device (D2D) applications. Ad hoc networks, however, are still plagued by interference caused by uncoordinated transmissions which leads to poor scaling due to distributed coordination. Communication with millimeter-wave (mmWave) devices offers hope to ad hoc networks through higher bandwidth, reduced interference due to directional antennas, and weaker interference power due to building blockage.
In our group, we used a stochastic geometry approach to characterize the one-way and two-way signal-to-interference ratio (SINR) distribution of a mmWave ad hoc network with directional antennas, random blockages, and ALOHA channel access. The effect of random receiver location is quantified which shows that random receiver distances do not alter the SINR distribution beyond knowledge of the mean receiver position. A method for computing the distribution of mmWave ad hoc interference-to-noise ratio which shows that mmWave ad hoc networks can still be interference limited. Several reasonable simplifications are used to derive the transmission capacity and area spectral efficiency. The performance of mmWave is then analyzed in terms of rate coverage. The results show that mmWave networks can support higher densities and larger spectral efficiencies, even in the presence of blockage, compared with lower frequency communication for certain link distances. Due to the increased bandwidth, the rate coverage of mmWave can be much greater than lower frequency devices.
A. Thornburg, Robert Daniels, and R. W. Heath, Jr., “Capacity and Scaling Laws of Dense mmWave and Interference Alignment Ad Hoc Networks”, to appear in Proc. of the IEEE Military Communications Conference, Baltimore, MD, October 1-3, 2016.
A. Thornburg and R. W. Heath, Jr., “Capacity and Coverage in Clustered LOS mmWave Ad Hoc Networks”, to appear in Proc. of IEEE Global Communications Confererence (GLOBECOM), Washington DC, December 4-8, 2016.
A. Thornburg, T. Bai, and R. W. Heath, Jr., “Interference Statistics in a Random mmWave Ad Hoc Network”, in Proc. of the IEEE Int. Conf. on on Acoustics, Speech, and Signal Processing, Brisbane, AUS, April 19-24, 2015. Video of presentation.
A. Thornburg and R. W. Heath, Jr., “Ergodic Capacity in mmWave Ad Hoc Networks with Imperfect Beam Alignment”, in Proc. of the IEEE Military Communications Conference, Tampa, FL, October 26-28, 2015. Video of presentation.
The work was supported Army Research Labs under Grant No. W911NF-12-R-0011 and the National Science Foundation under Grant No. 1218338.