20-44 GHz Mismatch Tolerant Programmable Dynamic Range with Inherent CMRR Square Law Detector for AGC Applications

This paper describes the design and measurement of a programmable dynamic range square-law power detector (PD) for a wideband mm-Wave transceiver operating at (20-44 GHz) frequency range. The PD is designed and fabricated in TSMC 0.18um BiCMOS technology. Theoretical analysis and CAD harmonic balance simulation were performed to show the detector performance. This detector is designed for AutomaticGain-control (AGC) for optimizing transceivers performance by setting the received and transmitted power to the required sweet operating spot range. The proposed square-law detector uses programmable resistance to switch between the available detection range, current subtraction technique to increase the available output voltage range, resistor degeneration to reduce the mismatches, and finally input cross capacitors to absorb the conversion gain reduction due to the degeneration and to provide high common mode rejection (CMR). In the matched frequency range, the measured input dynamic range has increased by 7 dB switchable range. The detector response is varying by around ±1 dBV for a given input RF power, as the RF frequency is swept across the operating frequency range. Static power consumption is 5.2mW from a 3.3 V supply.