A User Equipment in a wireless communication network includes a multiplicity of antennas, from which a subset of antennas is selected using a selection scheme synchronized to the network. A set of sub-carriers is selected from a plurality of sub-carriers using a selection scheme synchronized to the network. The UE receives a plurality of known reference symbols over the selected set of sub-carriers and through the selected subset of antennas. A frequency response for each selected sub-carrier is estimated over only the selected subset of antennas. The results are quantized and transmitted to the network on an uplink control channel.

The present invention provides a method of transmitting broadcast signals. The method includes, formatting, by an input formatting block, input streams into plural PLPs (Physical Layer Pipes); encoding, by an encoder, data in the plural PLPs; processing, by a framing and interleaving block, the encoded data in the plural PLPs to output at least one signal frame; and waveform modulating, by a waveform generation block, data in the at least one signal frame and transmitting, by the waveform generation block, broadcast signals having the waveform modulated data.

Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.

Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.

Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.