A pair of patch antennas are used to form a null slit antenna pattern for receiving GPS signals from at least three GPS satellites functioning as pseudo stars for spin rate and spin axis attitude determination for a spinning space vehicle in an earth orbit below the GPS satellites.
                                                                               Keywords:  GPS,  antenna
            
      
                                                                                                                                                                                                                                                                                                           International Class:  B64G1/24,  B64G1/36,  B64G1/66,  G01S1/00,  G01S5/02,  H01Q1/22,  H01Q1/28,  H01Q9/04,  H01Q21/28,  H01Q25/02,  G01S19/53,  G01S5/14