A technique for testing space object receivers using global navigation satellite system （GNSS） signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the ...A technique for testing space object receivers using global navigation satellite system （GNSS） signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the scenario of reciprocal displacement of the receiver relative to navigation satellites and their signals. In the first block, according to the known coordinates of the receiver which are specified in tabular form or analytically, the distances between the receiver and the navigation satellites are calculated as well as their relative velocities. According to these data, the second block synthesizes the signals of navigational travelers with the specified characteristics which are transmitted via the air or cable with a given attenuation to the receiver. This allows testing on the earth receivers for airplanes and space objects under different scenarios of their movement, which not only reduces the risk of problems during the flight, but also avoids significant economic costs. Based on real data obtained by approaching two spacecraft using a simulator, the receiver was tested, which shows the promise of the proposed technology.展开更多
When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered...When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered, earth-fixed (ECEF) co- ordinate, and attitude angles could be obtained through the rotation matrix between the body frame (BF) and the local level frame (LLF). Different from the conventional methods, a hybrid algorithm is presented to resolve attitude parameters utilizing the single differencing (SD) carrier phase equations established in LLF. Assuming that the cycle integer ambiguity is known, the measure- ment equations have attitude analytical resolutions by using simultaneous single difference equations for two in-view satellites. In addition, the algorithm is capable of reducing the search integer space into countable 2D discrete points and the ambiguity function method (AFM) resolves the ambiguity function within the analytical solutions space. In the case of frequency division multiple access (FDMA) for the Russian Global Orbiting Navigation Satellite System (GLONASS), a receiver clock bias estimation is employed to evaluate its carrier phase. An evaluating variable and a weighted factor are introduced to assess the integer ambiguity initialization. By static and dynamic ground experiments, the results show that the proposed approach is effective, with enough accuracy and low computation. It can satisfy attitude determination in cases of GPS alone and combined with GLONASS.展开更多
文摘A technique for testing space object receivers using global navigation satellite system （GNSS） signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the scenario of reciprocal displacement of the receiver relative to navigation satellites and their signals. In the first block, according to the known coordinates of the receiver which are specified in tabular form or analytically, the distances between the receiver and the navigation satellites are calculated as well as their relative velocities. According to these data, the second block synthesizes the signals of navigational travelers with the specified characteristics which are transmitted via the air or cable with a given attenuation to the receiver. This allows testing on the earth receivers for airplanes and space objects under different scenarios of their movement, which not only reduces the risk of problems during the flight, but also avoids significant economic costs. Based on real data obtained by approaching two spacecraft using a simulator, the receiver was tested, which shows the promise of the proposed technology.
文摘When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered, earth-fixed (ECEF) co- ordinate, and attitude angles could be obtained through the rotation matrix between the body frame (BF) and the local level frame (LLF). Different from the conventional methods, a hybrid algorithm is presented to resolve attitude parameters utilizing the single differencing (SD) carrier phase equations established in LLF. Assuming that the cycle integer ambiguity is known, the measure- ment equations have attitude analytical resolutions by using simultaneous single difference equations for two in-view satellites. In addition, the algorithm is capable of reducing the search integer space into countable 2D discrete points and the ambiguity function method (AFM) resolves the ambiguity function within the analytical solutions space. In the case of frequency division multiple access (FDMA) for the Russian Global Orbiting Navigation Satellite System (GLONASS), a receiver clock bias estimation is employed to evaluate its carrier phase. An evaluating variable and a weighted factor are introduced to assess the integer ambiguity initialization. By static and dynamic ground experiments, the results show that the proposed approach is effective, with enough accuracy and low computation. It can satisfy attitude determination in cases of GPS alone and combined with GLONASS.
