Patent ID: 11881877
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A method for calibration of a transceiver (TRX) comprising a transmitter (TX) and a measurement receiver (MRX), the method comprising:
producing a plurality of TX local oscillator (LO) signals by a first LO generator comprising a first frequency doubler and a first frequency divider, the first frequency doubler being configured to receive a voltage controlled oscillator (VCO) signal having a first frequency and generate a first signal fed into the first frequency divider, the first signal having a second frequency that is twice the first frequency;
producing a plurality of MRX LO signals by a second LO generator comprising a second frequency doubler and a second frequency divider, the second frequency doubler being configured to receive the VCO signal and generate a second signal fed into the second frequency divider, the second signal having the second frequency;
in a calibration mode, configuring the TX and the MRX to operate at a same LO frequency;
producing measurement signals including a second order counter-intermodulation (CIM2) signal caused by asymmetry of the first frequency doubler; and
generating a symmetry adjustment code based on the measurement signals; and
adjusting symmetry of the first frequency doubler based on the symmetry adjustment code.