  In this study, a channel estimator for millimeter wave (mmWave) systems is
proposed. By considering the sparse nature of channels in millimeter wave band,
the channel estimation problem formulated as an atomic norm minimization
problem. Previous studies on mmWave channel estimation have focused on
frequency flat channels. However, in this study the work is based on a
frequency selective channel and adopted atomic norm minimization and reweighed
atomic norm minimization technique for channel estimation in the frequency
domain. Simulation results verify the accuracy of the atomic and reweighted
atomic norm minimization techniques.
