Phase-rotated reference signals for multiple antennas

摘要

Systems, methods, and apparatuses for phase-rotated reference signals are provided. In accordance with one implementation, phase-rotated reference signals are transmitted from multiple transmit antennas on the same reference signal (RS) resource elements. The receiver may determine channel coefficients for links corresponding to the multiple antennas, based on the received signals at the RS resource elements. Time-domain filtering or frequency-domain orthogonal codes may be used to determine the channel coefficients for links corresponding to the multiple antennas. The phase-rotation information may be broadcasted in a system information block (SIB) message or signaled in a radio resource control (RRC) message.

主权项

1. A method of wireless communication in an Orthogonal Frequency Division Multiplexing (OFDM) system, comprising:
receiving a plurality of signals at a receive antenna on a plurality of reference signal (RS) resource elements of the OFDM system, the plurality of received signals each comprising one of a first set of reference signals transmitted from a first transmit antenna and one of a second set of reference signals transmitted from a second transmit antenna, wherein the one of the second set of reference signals transmitted from the second transmit antenna is identical to a first phase rotation of the one of the first set of reference signals transmitted from the first transmit antenna in a frequency domain; executing a Fast Fourier Transform (FFT) operation based on the plurality of received signals; calculating a plurality of frequency domain channel weights based on the FFT operation; and determining a first set of channel coefficients between the first transmit antenna and the receive antenna, and a second set of channel coefficients between the second transmit antenna and the receive antenna, based at least in part, on the plurality of frequency domain channel weights.