Patent ID: 8891646

Claim:
A method performed by a transmitting node of a wireless communication system, the transmitting node being capable of multi-antenna transmission, the method comprising: transmitting a plurality of common pilot signals from a plurality of antennas; determining whether a data demodulation at a receiving node can be enhanced; transmitting data to the receiving node during a data transmission time; and transmitting one or more demodulation pilot signals to the receiving node when it is determined that the data demodulation at the receiving node can be enhanced, wherein each common pilot signal is transmitted from one antenna, and no antenna transmits more than one common pilot signal, wherein the plurality of common pilot signals include one or more legacy common pilot signals and one or more non-legacy common pilot signals, each legacy common pilot signal being transmitted at a higher power than each non-legacy common pilot signal, and wherein each legacy common pilot signal is understood by both legacy receiving nodes and non-legacy receiving nodes, and each non-legacy common pilot signal is understood by non-legacy receiving nodes but is not understood by legacy receiving nodes.