This paper derives the outage probability and transmission capacity of ad hoc wireless networks with nodes employing multiple antenna diversity techniques, for a general class of signal distributions. This analysis allows system performance to be quantified for fading or non-fading environments. The transmission capacity is given for interference-limited uniformly random networks on the entire plane with path loss exponent α > 2 in which nodes use: (1) static beamforming through M sectorized antennas, for which the increase in transmission capacity is shown to be Θ(M 2 ) if the antennas are without sidelobes, but less in the event of a nonzero sidelobe level; (2) dynamic eigen-beamforming (maximal ratio transmission/combining), in which the increase is shown to be Θ(M 2 α ); (3) various transmit antenna selection and receive antenna selection combining schemes, which give appreciable but rapidly diminishing gains; and (4) orthogonal space-time block coding, for which there is only a small gain due to channel hardening, equivalent to Nakagami-m fading for increasing m. It is concluded that in ad hoc networks, static and dynamic beamforming perform best, selection combining performs well but with rapidly diminishing returns with added antennas, and that space-time block coding offers only marginal gains.

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Multiple antennas have become a common component of wireless networks, improving range, throughput, and spatial reuse, both at the link and network levels. At the same time, carrier sensing is a widely used method of improving spatial reuse in distributed wireless networks, especially when there is limited coordination among non-communicating nodes. While the combination of carrier sensing and multiple antennas has been considered in the literature, physical layer spatial models and the attendant consequences have not been included. The primary reason for this has been the difficulty of analyzing functionals of interacting point processes. Having developed new methods of quantifying physical layer performance with robust spatial network models, we use these techniques to address the following questions: What multiple antenna techniques produce the best network performance, and what is the performance gain? And, how should multiple antennas interact with carrier sensing parameters? Overall, the analysis confirms the significant benefit of multiple antennas in distributed wireless networks.

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Abstract-This paper presents analysis results of synchronized phasor data from 10 disturbance events recorded in the US Eastern Interconnection (EI). The phasor data covers a wide region in the EI, allowing for the study of disturbance propagation, interarea modes, and oscillations in voltages and currents. The analysis is not straightforward because the EI is a meshed system with adequate interarea mode damping. Disturbances involving tripping a single large generator unit produce very short interarea swing responses. Islanding events involving regions at the perimeter, however, provide more prominent responses for analysis.