John Wiley & Sons
This paper presents a study of the Mean-Squared Error (MSE) and throughput performance of Superimposed Pilots (SP) for the estimation of a Multiple-Input Multiple-Output (MIMO) wireless channel. The Cramer-Rao Bound (CRB) is derived for SP based estimation of the MIMO channel matrix. Employing the CRB analysis, it is proved that the asymptotic MSE bound is potentially 3 dB lower than the MSE performance of the existing SP Mean based Estimation (SPME) schemes. Motivated by this observation, a novel SP semi-blind scheme is presented for MIMO channel estimation. This scheme asymptotically achieves the CRB and hence has a lower MSE of estimation when compared with SPME schemes.