RF circuit (HF-S) for Tx Carrier Aggregation, comprising - a
diplexer (DI) with a first port (P1), a common port (PG) and a second port (P2), - a first
duplexer (DU-HB-1) for a first
frequency band with a transmit port (TX), a common port (PG) and a receive port (RX), - a first
duplexer (DU-LB-1) for a second
frequency band with a transmit port (TX), a common port (PG) and a receive port (RX), wherein the first
frequency band is the 2 GHz band or the 2.5 GHz band and the second frequency band is the 1 GHz band, - a first
signal path (SP1) between the common port (PG) of the first
duplexer (DU-HB-1) of the first frequency band and the first port (P1) of the
diplexer (DI), wherein the first
signal path (SP1) connects the common port (PG) of the first duplexer (DU-HB-1) of the first frequency band to the first port (P1) of the
diplexer (DI), - a second
signal path (SP2) between the common port (PG) of the first duplexer (DU-LB-1) of the second frequency band and the second port (P2) of the diplexer (DI), - in the second signal path (SP2) a phase shifter (PS) which is designed to match the impedances of the first duplexer (DU-LB-1) of the second frequency band and the diplexer (DI) for at least one
harmonic of one of the frequency bands in such a way that at least one
intermodulation product is reduced, wherein the phase shifter (PS) is tunable in its
phase offset.