Radio frequency front-end unit of portable communication and navigation tester

The utility model discloses a radio frequency front end unit of a portable communication and navigation tester. The frequency synthesizer comprises three local oscillator generators, three filters, amultiplier, ten switches, an attenuator, a high-power attenuator, a frequency mixer, two AM modulation modules, five couplers, three amplifiers, a power measurement unit, a radio frequency I/O connector, a protection circuit, a voltage standing-wave ratio circuit unit, an intermediate frequency output unit, a frequency divider and an antenna connector. Compared with the prior art, according to theutility model, the mixer and the two radio frequency switches are added to a three-mode output circuit; the radio frequency front-end unit is capable of outputting intermediate frequency signals, that is, a receiving circuit is integrated on the radio frequency transmitting circuit, and the radio frequency front-end unit has a transmitting mode and a receiving mode, so that the portable communication and navigation tester