Apple Inc.
FREQUENCY TRACKING FOR BEAMFORMED SYSTEMS

Abstract:

Systems, methods, and baseband processors are provided to generate or process symbols in a synchronization subframe. In one example, a method includes selecting non-consecutive orthogonal frequency division multiplexing (OFDM) symbols in a synchronization subframe. A transmitter is instructed to transmit demodulation reference symbols (DM-RS) on identical first sets of subcarriers in respective OFDM symbols of the selected non-consecutive OFDM symbols for a Physical Broadcast Channel (PBCH) using a same transmit beam, wherein a gap between two subcarriers in a respective set of the identical first sets of subcarriers is three subcarriers. The transmitter is instructed to transmit the PBCH on identical second sets of subcarriers in respective OFDM symbols in the selected non-consecutive OFDM symbols.