Abstract: An apparatus for envelope tracking calibration for use in a wireless communication is provided. The apparatus includes a transmission signal path configured to carry a transmission signal to an antenna. An envelope signal path configured to feed an envelope signal with an envelope tracking power amplifier. A controller is configured to transmit a normal envelope signal being generated in a normal operation mode and measure a first Adjacent Channel Leakage Ratio (ACLR) corresponding to the normal envelope signal. The controller is further configured to transmit a comparison envelope signal being generated in a comparison operation mode and measure a second ACLR corresponding to the comparison envelope signal. The controller is configured to calculate a time misalignment between the transmission signal path and the envelope signal path based on a difference between the first and second ACLRs.

Abstract: An apparatus for matching impedance for use in a wireless communication is provided. The apparatus includes a forward path carrying a transmission signal to an antenna. The apparatus further comprises a quadrature feedback path configured to extract and feed back in-phase and quadrature phase components from each of a forward signal being transmitted toward the antenna and a reverse signal reflected from the antenna. A tunable matching network (TMN) is coupled to the forward path, having a plurality of tunable elements for matching an internal impedance to an impedance of the antenna. A controller is configured to calculate TMN input impedance's amplitude and phase based on the in-phase and quadrature phase components from each of the forward signal and the reverse signal.

Abstract: An apparatus for envelope tracking calibration for use in a wireless communication is provided. The apparatus includes a transmission signal path configured to carry a transmission signal to an antenna. An envelope signal path configured to feed an envelope signal with an envelope tracking power amplifier. A controller is configured to transmit a normal envelope signal being generated in a normal operation mode and measure a first Adjacent Channel Leakage Ratio (ACLR) corresponding to the normal envelope signal. The controller is further configured to transmit a comparison envelope signal being generated in a comparison operation mode and measure a second ACLR corresponding to the comparison envelope signal. The controller is configured to calculate a time misalignment between the transmission signal path and the envelope signal path based on a difference between the first and second ACLRs.