Throughput Enhancement Using Multiple Antennas in OFDM-based Ad Hoc Networks under Transceiver Impairments

Hoc Networks under Transceiver Impairments Pengkai Zhao, and Babak Daneshrad Wireless Integrated Systems Research (WISR) Group, Electrical Engineering Department, University of California, Los Angeles, CA 90095 USA (e-mail: [email protected]; [email protected]) Abstract Transceiver impairments, including phase noise, residual frequency offset, and imperfect channel estimation, significantly affect the performance of Multiple-Input Multiple-Output (MIMO) system. However, these impairments are not well addressed when analyzing the throughput performance of MIMO Ad Hoc networks. In this paper, we present an analytical framework to evaluate the throughput of MIMO OFDM system under the impairments of phase noise, residual frequency offset, and imperfect channel estimation. Using this framework, we evaluate the Maximum Sum Throughput (MST) in Ad Hoc networks by optimizing the power and modulation schemes of each user. Simulations are conducted to demonstrate not only the improvement in the MST from using multiple antennas, but also the loss in the MST due to the transceiver impairments. The proposed analytical framework is further applied for the distributed implementation of MST in Ad Hoc networks, where the loss caused by impairments is also evaluated. Index Terms MIMO, OFDM, Ad Hoc, phase noise, residual frequency offset, imperfect channel estimation, link adaptation