Abstract: A method is disclosed to correct the IQ mismatch of an RF transceiver. The method generates a reference signal down a transmitting-receiving loop and measures the received signals SDTA-1 and SDTA-2, respectively dominated by their desired component and image component, under two programmed mixer settings of operating mode and LOF. The method then calculates a system image rejection ratio (IRRsys) with SDTA-1 and SDTA-2, systematically adjusts the amplitude and phase pre-distortion of the transmitting baseband signals till IRRsys is maximized thus correcting for the transmitter IQ mismatch. The now-corrected transmitter IQ mismatch is then used to correct receiver IQ mismatch by reprogramming the first setting and measuring mismatches in amplitude ?A and phase ?? between received baseband IQ signals, corrects for ?A and ?? accordingly and stores the corrective values for future compensation of receiver IQ mismatch.

Abstract: A Wireless LAN (WLAN) receiver with packet level Automatic Gain Control (AGC) is disclosed for receiving and converting an RF packet signal, conforming to the open standard IEEE 802.11, into recovered digital data. The receiver comprises a switchably coupled antenna, an analog signal processing circuitry for conditioning and selective frequency down-converting the RF signal into amplified, under a controllable analog gain G1A, video signals VSI and VSQ, an Analog to Digital Converter (ADC) for converting VSI and VSQ into digital outputs IADC and QADC and an AGC subsystem for effecting an adjustment of G1A and for digitally scaling, under a controllable digital gain G2D, the digital outputs LADC and QADC before final digital data recovery. The AGC subsystem further comprises a Calibration and Gain Setting firmware for measuring the preambles of each RF packet and responsively adjusting both G1A and G2D.

Abstract: A configurable dual-band RF transceiver with a cascaded frequency conversion scheme (DBXVR) is disclosed for the processing of any selected RF channel signal specified by the open standard IEEE 802.11 a/b/g for Wireless LAN. The DBXVR comprises two switchably connected antennae for receiving and transmitting any selected RF channel signal and two subsets of signal processing hardware. The first signal processing subset is designed to perform all related frequency conversion, signal filtering and amplification between the b/g-band and its corresponding Baseband Inphase (I) and Quadrature (Q) signals.