By exploiting multiple transmissions of orthogonal coding signal and single reception

a new GMTI processing scheme for ground moving targets detection with low velocity in space-borne multiple input and single output (MISO) radar systems is presented in the paper.Firstly

the requirements of multiple orthogonal coding waveform for the MISO radar system is analysed in detail. Focusing on this new scheme

an orthogonal waveform optimization design method is also proposed.In this GMTI processing scheme

different satellites independently transmit the optimized orthogonal waveform and one of the transmission satellites acts as the receiver and matches the received echo signal with each of the transmission signal

respectively.Detection of ground moving targets with low velocity can be achieved by joint adaptive two-dimension processing of multi-channel and multi-pixel on image domain.In this way

data communications among multiple satellites is not necessary and hence real time processing capability of the whole system can be improved.The performance of one-dimension image after matching by the receiving satellite

i.e.the shape of its mainlobe and the performance of its sidelobe is considered as the optimization criteria in the proposed waveform design method.Simulations and analysis are performed to testify the feasibility and effectiveness of the proposed system and waveform design method

in terms of the orthogonality of waveform

convergence of the design algorithm

clutter cancellation

and detection performance of targets.