Design And Implementation Of Low-power Multi-mode GNSS Receiver For Pico-satellite

With the rapid development of aviation technology,Pico-satellites which have lots of superiorities such as short development cycle,low cost,miniature volume,light weight,flex-ible launch method and so on,have become a trend of the development of artificial satellites.In particular,the formation of Pico-satellites is favored by countries with the powerful ad-vantages which a single ordinary satellite can not be matched.The great advantages of the formation of Pico-satellites also drive the development of GNSS receiver constantly towards miniaturization and low power consumption.The current onboard GNSS receivers are mainly GPS-based that seriously restricts the development of the space industry of China.As the construction of Beidou navigation system,research and implementation of multi-mode and multi-frequency GNSS receiver onboard,which is low-power and compatible with GPS and Beidou,has become more and more important research topics in the development and appli-cation of Pico-satellite.Aming at the Chinese onboard GNSS receivers existing shortcomings such as high power consumption,limited processing capacity and so on,this paper proposes the overall design of the low-power GNSS receiver which can work at dual-mode four-frequency or sin-gle-mode dual-frequency mode,with the actual demands for onboard GNSS receivers,based on the single-mode dual-frequency GNSS receiver,a payload of the ZDPS-2(A/B),designed by Zhejiang University.At the same time,considering the scalability and flexibility of the GNSS receiver platform,the whole hardware of the receiver is divided into three parts:RF amplification and shunt module,RF front-end module,baseband processing and calculation module.The chips are selected according to power consumption and other performance indi-cators of the receiver.Then the characteristics of the chips are analyzed in detail.The system software codes are simulated modularly and ultimately integrated into the hardware platform.Finally,the realized multi-mode GNSS receiver has advantages of small size,light weight,low power consumption,flexible working mode,and powerful baseband processing capabil-ity and so on,which fulfill the application requirements of the Pico-satellite well.The low-power multi-mode GNSS receiver designed and implemented for Pico-satellite in this paper can receive the navigation signals of GPS(L1 and L2)and the Beidou naviga-tion system(B1 and B3)at the same time.The receiver is compatible with GLONASS navi-gation system.It also can receive the navigation signal of one system alone in a specific task with lower power consumption.The experiments demonstrate that the low-power multi-mode GNSS receiver can meet all the requirements well.The size of the receiver is only 12cm×8cm X 2.5cm.The whole board power can be controlled within 4.4 watts in the dual-mode four-frequency with 48 channels working mode.Respectively,the positioning accuracies on the x-axis,y-axis and z-axis are 1.39m(1σ),4.76m(1σ)and 1.58m(1σ),and its receive sen-sitivity can achieve-132dBm.It can basically satisfy the practical engineering application requirements of the specific Pico-satellite missions.