L band

About: L band is a research topic. Over the lifetime, 674 publications have been published within this topic receiving 4570 citations.

Monitoring of mining induced surface deformation using L-band SAR interferometry

Abstract: In the mining context there is a specific interest in monitoring temporally non-uniform high deformation rates with high spatial gradients. In recent years land surface deformation monitoring with SAR data reached some maturity. Mainly C-band SAR data were used. Nevertheless, there remain important limitations to the availability of the interferometry based deformation information. Reasons include incomplete spatial coverage with information gaps for low coherence areas, problems in resolving high deformation gradients, and problems in resolving temporally non-uniform deformation. The objective of our contribution is to demonstrate that these limitations are significantly reduced at L-band. In vegetated areas and for fast deformations a good applicability of Lband INSAR was found.

Frequency sharing between satellite and terrestrial systems in the Ka band: A database approach

Abstract: Broadband access by satellite in Ka band is currently constrained by spectrum availability. In this context, the EU FP7 project CoRaSat is examining the possible ways in which improved frequency utilization could be possible in Ka band via the use of cognitive mechanisms. A database approach utilizing spectrum scenarios between Fixed Satellite Services (FSS), Fixed Services (FS) and Broadcast Satellite Service (BSS) feeder links are considered. Interference in the downlink from BSS and FS are evaluated using real data bases and propagation models. Data base statistics for several EU countries are also evaluated. The importance of using correct terrain profiles and accurate propagation models is shown. For the case of the BSS interference to the FSS downlink it is demonstrated that for the UK an area of less than 2% is affected and thus the additional 400 MHz spectrum band (17.3 to 17.7 GHz) can be used by FSS over the majority of the country. The operational challenges of the database approach across the EU are also discussed.

Effect of the 24 September 2011 solar radio burst on precise point positioning service

Abstract: An intense solar radio burst occurred on 24 September 2011, which affected the tracking of Global Navigation Satellite Systems’ (GNSS) signals by receivers located in the sunlit hemisphere of the Earth. This manuscript presents for the first time the impacts of this radio burst on the availability of Fugro’s real-time precise point positioning service for GNSS receivers and on the quality of the L band data link used to broadcast this service. During the peak of the radio burst (12:50–13:20 UT), a reduction in the L band signal-to-noise ratio (SNR) is observed. For some receiver locations, a reset in the position filter is observed, which can be either due to the reduction in the L band SNR or the reduction in the number of tracked GNSS satellites. This reset in the position filter is accompanied by degradation in the positioning accuracy, which is also discussed herein.