Abstract:
Dynamic DC offset is one of the biggest problems preventing the implementation of
single chip receivers. This thesis presents a 2.4GHz downconversion mixer designed to
work with adaptive DC offset cancellation for a fully integrated direct conversion
receiver. Offset can be removed by dynamically changing the PFET load bias in a
Gilbert Cell type mixer. A dual-loop algorithm, which was developed in separate work,
controls a current-steering DAC that dynamically changes the PFET load bias of the
mixer. The mixer has a gain of 8dB, an IIP3 of l7dBm, and a noise figure of 15dB. In
addition a CMOS RF Front-End incorporating the offset cancellation mixer is presented
that meets the specifications for Bluetooth.
