Satellite-based Localization of IoT Devices using Joint Doppler and Angle-of-Arrival Estimation

While   global   navigation   satellite   system   (GNSS)technologies have always been the go-to solution for localizationproblems, they may not be the best choice for some Internet-of-Things (IoT) applications due to the incurred power consumptionand cost. In this paper, we present an alternative satellite-basedlocalization method exploiting the signature of Doppler shifts andangle  of  arrival  measurements  as  seen  by  a  receiving  satellite.We first derive the joint likelihood function of the measurements,which  is  represented  as  a  combination  of  three  Gaussian  distri-butions.  Then,  we  show  that  the  maximum  likelihood  problemreduces  to  a  more-efficient  mean  squared  error  minimizationin  the  Gaussian  case  as  inferred  from  real  measurements  wecollected  from  low-earth-orbit  satellite  using  a  tracking  groundstation.  Thus,  we  propose  utilizing  a  stochastic  optimizer  tosearch for the global minimum of the mean squared error whichrepresents the location of the ground IoT device as estimated bythe  satellite  platform.  The  emulated  results  show  that  the  IoTdevice localization, under such realistic model, can be performedwith  sufficient  accuracy  for  IoT  applications.