The present invention discloses radio frequency transmitting and receiving devices and an unmanned aerial vehicle system. The radio frequency transmitting device comprises: a first crystal oscillator, configured to provide a first clock signal with a frequency f; a reference signal receiving circuit, configured to receive a reference signal with a frequency (N−1)×f transmitted by a radio frequency receiving device; a frequency mixer, configured to perform frequency mixing processing on the first clock signal and the reference signal to obtain a carrier signal with a frequency N×f; a modulating circuit, configured to load a signal to be transmitted on the carrier signal, to obtain a frequency band signal; and a first transmitting circuit, configured to transmit the frequency band signal to the radio frequency receiving device. The radio frequency transmission performed according to the present invention has higher resistance to instantaneous vibration.