Efficient SER Estimation for MIMO Detectors via Importance Sampling Schemes

TitleEfficient SER Estimation for MIMO Detectors via Importance Sampling Schemes
Publication TypeConference Paper
Year of Publication2019
AuthorsElvira, V., and I. Santamaría
Conference NameAsilomar Conference on Signals, Systems, and Computer
Pagination712-716
Month PublishedNovember
Conference LocationPacific Grove, CA, USA
AbstractIn this paper we propose two importance sampling methods for the efficient symbol error rate (SER) estimation of maximum likelihood (ML) multiple-input multiple-output (MIMO) detectors. Conditioned to a given transmitted symbol, computing the SER requires the evaluation of an integral outside a given polytope in a high-dimensional space, for which a closed-form solution does not exist. Therefore, Monte Carlo (MC) simulation is typically used to estimate the SER, although a naive or raw MC implementation can be very inefficient at high signal-to-noise-ratios or for systems with stringent SER requirements. A reduced variance estimator is provided by the Truncated Hypersphere Importance Sampling (THIS) method, which samples from a proposal density that excludes the largest hypersphere circumscribed within the Voronoi region of the transmitted vector. A much more efficient estimator is provided by the existing ALOE (which stands for ``At Least One rare Event'') method, which samples conditionally on an error taking place. The paper describes in detail these two IS methods, discussing their advantages and limitations, and comparing their performances.