The utility model discloses an enough realize low costization, miniaturization, low power dissipation, simultaneously the higher crashproof millimeter wave radar system of car initiative of transmitter -receiver isolation degree. This system is including receiving and dispatching antenna module, radio frequency transmiting receiving component, data processing module, power supply, and radio frequency transmiting receiving component includes transmitting circuit and receiving circuit, the transmitting circuit includes phase locking frequency synthesizer, a low -pass filter, the frequency divider, voltage -controlled oscillator, a power distribution unit, the 2nd power distribution unit, power amplifier, the power frequency multiplier, receiving circuit includes low -noise amplifier, the 3rdpower distribution unit, fourth power distribution unit, the first looks ware that moves, the second moves the looks ware, first first detector, the second first detector, a frequency selective amplifier, the 2nd frequency selective amplifier, a R4 wave filter, the 2nd R4 wave filter, this radio frequency transmiting receiving component realizes the low costization under the system of assurance index prerequisite, it is miniaturized, the consumption has been reduced, the transmitter -receiver isolation degree has been improved simultaneously. Be fit for popularizing and applying at radar system.