High dynamic range receiver front-end with q-enhancement

Abstract

A preselect circuit maintains the dynamic range of a received RF input signal during bandpass filtering of the received RF input signal. The preselect circuit includes a Q-deficient passive bandpass filter for coupling to an antenna to receive a received RF input signal. The preselect circuit further includes a Q-enhancement circuit coupled to the Q-deficient passive bandpass filter, wherein the Q-enhancement circuit increases a Q-value of the Q-deficient passive bandpass filter by compensating for resistive inductive losses in the bandpass filter.

What is claimed is: 
     
         1 . A method, comprising:
 receiving an RF input signal from an antenna;   passively bandpass filtering the RF input signal in a Q-deficient passive bandpass filter prior to the RF input signal being subjected to any active circuit elements; and   enhancing a deficient Q-value of the Q-deficient passive bandpass filter.   
     
     
         2 . The method of  claim 1 , wherein the passively bandpass filtering the RF input signal further comprises maintaining a dynamic range of the RF input signal during the passively bandpass filtering. 
     
     
         3 . The method of  claim 1 , further comprising impedance transforming the RF input signal prior to passively filtering the RF input signal. 
     
     
         4 . A circuit, comprising:
 means for receiving an RF input signal from an antenna;   means for passively bandpass filtering the RF input signal in a Q-deficient passive bandpass filter prior to the RF input signal being subjected to any active circuit elements; and   means for enhancing a deficient Q-value of the Q-deficient passive bandpass filter.   
     
     
         5 . The method of  claim 4 , further comprising means for impedance transforming the RF input signal prior to passively filtering the RF input signal.