A multiband RF transmitting and receiving apparatus and a method therefore
is capable of using a control voltage from a phase locked loop (PLL) to
control other components, as well as a voltage controlled oscillator
(VCO), of a multiband RF transceiver. The multiband transmitting and
receiving apparatus adjusts a capacitance value of a varactor in a power
amplifier (PA) and a low noise amplifier (LNA) including an LC parallel
resonance circuit, respectively, using the control voltage from the PLL
and controls a current flowing to a mixer. Accordingly, the components in
the multiband RF transceiver are able to operate a greater number of
frequency bands than a single frequency band, thereby reducing the number
of components required to design the multiband RF transceiver.