Method for downlink communication by means of a downlink superimposed radio signal, a base station and a user terminal therefor

A base station (BS) for downlink communication with a user terminal (LP-UE) by means of a downlink superimposed radio signal comprising downlink data for the user terminal (LP-UE) and for at least one further user terminal (ImP-UE, HP-UE) that are transmitted using the same radio resources, said base station (BS) comprising at least one processing means adapted to

• transmit the downlink data for the user terminal (LP-UE) with lower power than the downlink data for the at least one further user terminal (ImP-UE, HP-UE),
• and send control information in downlink to the user terminal (LP-UE) that enables the user terminal (LP-UE) to decode the downlink data for the at least one further user terminal (ImP-UE, HP-UE).

A user terminal (LP-UE) for downlink communication with a base station (BS) by means of a downlink superimposed radio signal comprising downlink data for the user terminal (LP-UE) and for at least one further user terminal (ImP-UE, HP-UE) that are transmitted using the same radio resources, said user terminal (LP-UE) comprising at least one processing means adapted to

• successively reduce the superimposed radio signal by decoding the downlink data for the at least one further user terminal (ImP-UE, HP-UE) in the order of the downlink transmission power starting with the highest one, reconstructing a radio signal of the downlink data for the at least one further user terminal (ImP-UE, HP-UE), and subtracting the radio signal of the downlink data for the at least one further user terminal (ImP-UE, HP-UE) from the superimposed radio signal,
• and decode its own downlink data using the superimposed radio signal that has been reduced by the radio signal for the at least one further user terminal (ImP-UE, HP-UE).