TY - JOUR N2 - The cold start of the space GPS receiver, i.e. the start without any information about the receiver position, satellite constellation, and time, is complicated by a large Doppler shift of a navigation signal caused by the satellite movement on the Earth orbit. That increases about five times the search space of the navigation signals compared to the standard GPS receiver. The paper investigates a method of the acceleration of the GPS receiver cold start time designed for the pico- and femto-satellites. The proposed method is based on a combination of the parallel search in Doppler frequency and PRN codes and the serial search in code phase delay. It can shorten the cold start time of the GPS receiver operating on LEO orbit from about 300 to 60 seconds while keeping the simplicity of FPGA signal processor and low power consumption. The developed algorithm was successfully implemented and tested in the piNAV GPS receiver. The energy required for the obtaining of the position fix was reduced five times from 36 on to 7.7 Joules. This improvement enables applications of such receiver for the position determination in smaller satellites like Pocket Cube or femto-satellites with a lower energy budget than the Cube Satellite. L1 - http://www.czasopisma.pan.pl/Content/117131/PDF/100_2473_Kovar_skl.pdf L2 - http://www.czasopisma.pan.pl/Content/117131 PY - 2020 IS - No 4 EP - 752 DO - 10.24425/ijet.2020.134036 KW - FPGA KW - navigation KW - low earth orbit KW - acquisition accelerator A1 - Kovář, Pavel PB - Polish Academy of Sciences Committee of Electronics and Telecommunications VL - vol. 66 DA - 2020.12.02 T1 - Start Acceleration of the Space GPS Receiver SP - 745 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/117131 T2 - International Journal of Electronics and Telecommunications ER -