A radio-frequency receiver for, e.g., receiving GPS signals in a cellular
telephone has an input, a first gain stage in the form of a linear low
noise amplifier with voltage-voltage feedback and a resonant load, and a
second gain stage based on a common source input transconductor.
Associated with the input and the first gain stage is a filter comprising
a notch filter part for rejecting an interfering signal, e.g. a cell
phone transmitter signal, and, connected between the parallel resonant
circuit and the input, a series capacitance which, in combination with
the inductor of the parallel-resonant circuit, forms a series-resonant
circuit to provide a low impedance path at a wanted signal frequency.