The present invention is related to low power low noise amplifiers (LNA)
including on/off switching capability, which are preferably used for
impulse radio (IR) ultra-wideband (UWB) receivers. In the invention a
very low power and high-gain Common-Gate Capacitive Cross Coupling
Cascaded LNA is proposed, to provide an optimum gain for large ON times.
The invention provides also a Common-Source Cascoded LNA for shorter
received pulse widths, with the aim of implementing a fast ON/OFF
switching. An input signal is applied to a first amplifying stage and the
switching means are coupled to a second amplifying stage so that they do
not interfere with the matching network of the first stage. The invention
is also related to a method of amplifying a radio frequency signal using
a plurality of low noise amplifying elements.