Patent attributes
A calibration architecture that enables accurate calibration of radio frequency (RF) integrated circuits (ICs) chips used in transceiver RF systems in a relatively simple testing environment. Embodiments of the invention include one or more on-chip switchable internal calibration paths that enable direct coupling of a portion of the on-chip circuit to an RF test system while isolating other circuitry on the chip. Some embodiments allow interconnection of switchable internal calibration paths between separate IC chips. Still other embodiments utilize internal switches and antenna mutual coupling to provide over-the-air calibration, alone or in combination with direct signal coupling via internal calibration paths. Periodic self-calibration of an RF IC can be performed after initial factory calibration, so that adjustments in desired performance parameters can be made while such an IC is embedded within a final system, and/or to take into account component degradation due to age or other factors.