A full duplex microwave front end (300, 400, 500, 600, 800) for the communication system of an unmanned aerial vehicle such as a drone, comprising: —a transmitter module (310, 410, 510, 610, 710, 810) capable of selecting an antenna (311, 312, 411, 412, 511, 512, 611, 612, 711, 712), the most appropriate one at a given time, in order to emit and/or receive a signal, —a filter module (320, 420, 520, 620, 720, 820), capable of insulating the emission function from the reception function in order to emit the signal or insulating the reception function from the emission function in order to receive the signal, and —an amplifier module (340, 440, 540, 640, 740, 840), capable of amplifying the weak signal received in order to demodulate it, or capable of amplifying the power of the modulated signal intended to be emitted, characterized in that it comprises, —a switch module (330, 430, 530, 630, 730, 830) capable of switching the frequency bands B1 and B2 used for emitting and receiving the said signal respe