Radio frequency tunable polyphase filter design

Polyphase filters are widely used in radio frequency (RF) receivers either to generate accurate quadrature signals or to reject the image. Analytical modeling of passive polyphase filter suitable for RF front-end applications is exposed. This analytical study has been used to calibrate the optimal values of passive components in order to obtain the maximum image rejection ratio (IRR). Component matching and parasitics reduction techniques have been taken into account. Tunable RC polyphase filter, suitable for multi-standard applications, has been fabricated in 0.13-µm CMOS technology.