Power amplification system (S) for radio frequency communications, comprising: - at least one input port (IN) of an input radio frequency signal (RF IN); - at least one output port (OUT) of an output radio frequency signal (RF OUT); - at least one digital predistortion unit (DPD) operatively interposed between said input port (IN) and said output port (OUT); - quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) operatively interposed between said digital predistortion unit (DPD) and between at least one of said input port (IN) and said output port (OUT); at least one observation port (OBS) connected to said output port (OUT) and to said quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) and adapted to receive an observed radio frequency signal (RF OBS); and in that said quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) comprises: - at least one input correction unit (QMC IN) operatively interposed between said input port (IN) and said digital predistortion unit (DPD) - at least one output correction unit (QMC OUT) operatively interposed between said digital predistortion unit (DPD) and said output port (OUT); - at least one observation correction unit (QMC OBS) operatively interposed between said observation port (OBS) and said digital predistortion unit (DPD); wherein the power amplification system (S) further comprises: - at least one switch (RF SW) positionable between a first configuration, wherein it connects said input port (IN) to an intermediate frequency, IF, conversion unit (CNV IF), and a second configuration, wherein it connects said observation port (OBS) to said IF conversion unit (CNV IF); - the IF conversion unit (CNV IF) connected to said quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) and adapted to convert said input radio frequency signal (RF IN) into a respective intermediate frequency input signal in said first configuration, and adapted to convert said observed radio frequency signal (RF OBS) into a respective observed intermediate frequency signal in said second configuration. - at least one input port (IN) of an input radio frequency signal (RF IN); - at least one output port (OUT) of an output radio frequency signal (RF OUT); - at least one digital predistortion unit (DPD) operatively interposed between said input port (IN) and said output port (OUT); - quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) operatively interposed between said digital predistortion unit (DPD) and between at least one of said input port (IN) and said output port (OUT); - at least one input correction unit (QMC IN) operatively interposed between said input port (IN) and said digital predistortion unit (DPD) - at least one output correction unit (QMC OUT) operatively interposed between said digital predistortion unit (DPD) and said output port (OUT); - at least one observation correction unit (QMC OBS) operatively interposed between said observation port (OBS) and said digital predistortion unit (DPD); - at least one switch (RF SW) positionable between a first configuration, wherein it connects said input port (IN) to an intermediate frequency, IF, conversion unit (CNV IF), and a second configuration, wherein it connects said observation port (OBS) to said IF conversion unit (CNV IF); - the IF conversion unit (CNV IF) connected to said quadrature modulation correction means (QMC IN, QMC OUT, QMC OBS) and adapted to convert said input radio frequency signal (RF IN) into a respective intermediate frequency input signal in said first configuration, and adapted to convert said observed radio frequency signal (RF OBS) into a respective observed intermediate frequency signal in said second configuration. <EOS>