On the multi-resolution ESPRIT algorithm

Multi-resolution ESPRIT is an extension of the ESPRIT direction finding algorithm to antenna arrays with multiple baselines. A short (half-wavelength) baseline is necessary to avoid aliasing, a long baseline is preferred for accuracy. The MR-ESPRIT algorithm allows us to combine both estimates. The ratio of the longest baseline to the shortest one is a measure of the gain in resolution. We show that, because of various factors, including noise, signal bandwidth and measurement error, the achievable gain in resolution is bounded.