METHOD AND APPARATUS FOR CHANNEL ESTIMATION IN DISTRIBUTED TRANSMIT DIVERSITY SYSTEMS

摘要

A distributed transmit diversity system based on OFDM signaling transmits a broadcast/multicast service signal from one or more first base stations and from one or more second base stations, wherein the first and second base stations transmit orthogonalized pilots. Correspondingly, a remote receiver, e.g., a mobile station, resolves the orthogonal pilots and makes independent channel estimates relative to the first and second base stations for improved diversity reception. Pilots are orthogonalized between the first and second base stations by using orthogonal space-time or space-frequency block coding. For example, in one embodiment, a first pilot tone pair is interleaved with data tones in the OFDM data blocks being transmitted from the first base stations, while an orthogonal second pilot tone pair is interleaved with data tones in the same OFDM data blocks being synchronously transmitted from the second base stations.