Star Student Project adopts the sparse channel estimator as described in for multiuser channel estimation, with the following modifications. The Doppler search ranges for different data streams are different. For each user, the dominant Doppler scale due to platform motion can be estimated, e.g., by preamble preceding data transmission or training sequences embedded in the transmission. On the first iteration of the iterative receiver, the Star Student Project data symbols are unknown, and the measurements on pilot subcarriers are severely contaminated by ICI.
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