Space vehicle inspection device based on GNSS reflection signal

The invention discloses a space aircraft detecting device based on GNSS reflected signals, comprising a computer, a right-hand antenna, a left-hand antenna, a Doppler relay mapping receiver and an inversion target position resolving unit; the right-hand antenna and the left-hand antenna are respectively connected with an input interface of the Doppler relay mapping receiver and the computer is connected with an output interface of the Doppler relay mapping receiver; the inversion target position resolving unit is stored in the computer. The detecting device comprehensively makes use of the received direct signals emitted by GNSS and the received direct signals emitted by GNSS which are reflected by the space aircraft to acquire the coordinates (X0, Y0 and Z0) of the space aircraft under a geocentric rectangular coordinate.