GARCIA ORDEIG Rodrigo

Abstract: This PhD thesis focuses on the design of low-power integrated radio-frequency front-ends for multistandard wireless receivers implemented in advanced CMOS technologies. Modern wireless communication systems increasingly rely on multistandard operation and Software Defined Radio (SDR) architectures, requiring broadband and reconfigurable RF front-ends capable of supporting several communication standards within the same hardware platform. In parallel, the continuous scaling of CMOS technologies has significantly increased transistor transition frequencies (fT), enabling the implementation of complex RF architectures operating up to several gigahertz in highly scaled integrated processes. The objective of this thesis is the co-design and possible integration of a Low Noise Amplifier (LNA) and an N-Path mixer for multistandard receiver applications. Unlike conventional approaches where both blocks are designed independently, this work proposes a global design methodology where the LNA and N-Path mixer are considered as a unified system. The research will investigate the interactions between both blocks, including dynamic impedance matching, switching-induced folding noise, wideband stability, and the management of periodic signals injected into the receiver chain. Several advanced circuit techniques will be explored to improve performance, power efficiency, and tunability. These include current reuse architectures, noise and distortion cancellation techniques, current-mode operation, and programmable gain approaches. Additional tunability mechanisms will also be investigated to complement the intrinsic frequency selectivity of N-Path mixers. Particular attention will be given to techniques inspired by continuous-time analog filters for adaptive tuning of input impedance, noise cancellation, and linearity optimization. The use of active inductors for frequency-band tuning in LNAs will also be studied. The research will additionally explore compact-model and look-up-table-based design methodologies, leveraging the experience of both collaborating research groups in advanced analog and RF circuit design techniques. Another important aspect of the thesis is the operation of RF front-ends under low supply voltages, which is increasingly important in deeply scaled CMOS technologies and low-power applications.