LESSONS LEARNED FROM MOBILE SATCOM PROPAGATION MEASUREMENT CAMPAIGNS AT C, S, AND K-BAND

摘要

In the last few years Joanneum Research has carried out several measurement campaigns within ESA/ESTECcontracts. The campaigns focused on both the satellite-to-indoor and the satellite-to-mobile channel. Measurementshave been carried out at S-, C-, and K- bands. Both continuous wave and wideband data (from a PropSound channelsounding device) have been measured. All measurement campaigns have used aircraft as platform for the transmitter.The measurements delivered unprecedented datasets that allowed determining path loss and delay- and anglespreadingof the received signal, which are the main parameters when modeling the channel, and indeed channelmodels have already been developed. This study, however, not only presents the main findings of the campaigns, butalso looks "behind the stage" of the measurement setup and the logistics of such measurements and addresses thelessons learned. When carrying out measurement campaigns with mobile transmitters and/or receivers, it is also therecorded auxiliary data that plays an important role. The exact position of the Tx and Rx, their attitude, the directionsof pointing antennas, and the surroundings of the Rx have to be available with high accuracy and rapid succession inorder to gain valuable data. In the presented campaigns the aircraft have been equipped with GPS sensors and inertialmeasurement units. These datasets were also recorded for the analysis and the data post processing in order to have aprecise view on the signal path geometry. With the knowledge of this geometry the buildings' entry losses could berelated to the structures and materials they penetrated (glass, metal facades, concrete structures, etc.). Equivalently,also in the mobile satellite case the attenuation of various types of roadside vegetation could be determined from theknowledge of the signal path geometry. Surveillance cameras with fish-eye-lenses have been used to document thedirect surrounding of the Rx in both the satellite to indoor case and the mobile satellite case. With all additionalinformation it was possible to explain certain effects in the signal caused by moving persons in the indoor case andby shadowing or reflections due to buildings, vegetation and traffic the mobile case.