Design and development of compact and monolithic direct conversion receivers

In this work, we study the direct down conversion (DDC) receiver architecture as an alternative to the common heterodyne topologies. A thorough analysis is performed to identify the advantages and disadvantages of direct conversion and to distinguish the challenges for a monolithic implementation of such topology. A subharmonic even-order frequency conversion scheme and several performance enhancement techniques are developed and thoroughly described by theoretical derivation. The developed theory and enhancement techniques are validated through experimental measurements and analysis.; Several integrated receiver MMICs are designed and fabricated in a commercial GaAs MESFET process for 5 to 6 GHz broadband wireless applications. Our experimental results show successful integration of RF and analog receiver building blocks in compact and low-power MMICs.