Multipoint data transmission

摘要

A semi-single frequency network (SFN) concept is presented. According to the SFN concept, the same data signal is transmitted from multiple base stations to a mobile terminal simultaneously on the same frequency band. Accordingly, the transmitted signals are combined in the radio channel and the mobile terminal experiences the transmitted signals as one signal propagated through a multipath channel. Additionally, each base station transmits a base station specific pilot signal. The mobile terminal carries out a channel estimation procedure for each received pilot signal and combines the channel estimates to obtain information how to equalize the received data signal. Then, the mobile terminal calculates equalization weights from the combined channel estimates and equalizes the received data signal.

主权项

1. A method, comprising:
receiving a multicast data transmission comprising a transmission by a first base station and a transmission by at least a second base station and a plurality of different pilot sequences transmitted from the base stations, wherein a different one of the pilot sequence is transmitted from each of the base stations; receiving a unicast data transmission from the first base station; calculating a plurality of radio channel estimates wherein each of the plurality of radio channel estimates is calculated for a radio channel for a portion of a transmission, contributed by one of the base stations to the multicast data transmission, and wherein the radio channel estimate for a base station is calculated from the pilot sequence received from that base station; equalizing the received multicast data transmission by utilizing the calculated plurality of radio channel estimates; and equalizing the received unicast data transmission from the radio channel estimate utilizing the pilot sequence transmission by the first base station, wherein the pilot sequence transmission by the first base station is the same pilot sequence used in calculating the radio channel estimate for transmission of the multicast data transmission from the first base station; combining the plurality of radio channel estimates; wherein equalizing the received multicast data transmission comprises equalizing the received multicast data transmission with weights calculated from the combined radio channel estimates by multiplying frequency components of the received multicast data transmission with a component of the combined radio channel estimates.