An entire radio transceiver can be completely integrated into one IC chip. In order to integrate the IF filters on the chip, a heterodyne architecture with a low IF is used. A single, directly modulated VCO is used for both up-conversion during transmission, and down-conversion during reception. Bond-wires...http://www.google.fr/patents/US6477148?utm_source=gb-gplus-shareBrevet US6477148 - Radio transceiver on a chip
