One of the significant features that makes Indian Regional Navigation Satellite System(IRNSS)distinct from most of the other satellite navigation systems is the use of S band signal along with the L-band signals.The f...One of the significant features that makes Indian Regional Navigation Satellite System(IRNSS)distinct from most of the other satellite navigation systems is the use of S band signal along with the L-band signals.The fact that S-band signals experience lesser ionospheric delays and therefore lesser ionospheric gradients than L-band signals is of great advantage,more-so in ionospheric storm conditions.The advantage of using IRNSS S-band signal under ionospheric storm conditions for Ground Based Augmentation System(GBAS)applications is investigated in this paper.The analysis is carried out by computing a GBAS parameter namely sigma-vertical-ionospheric-gradient(σvig)using data from low-latitude stations in Hyderabad,India(17.3850°N,78.4867°E)under both quiet and storm ionospheric conditions and then estimating vertical protection levels(VPLs).It is observed that even in storm conditions,σvig is only 5.08 mm/km with S1 as against 22.80 mm/km due to L5.Also,the VPLs are 0.65 m less than those with L5 and are well within the alert limits.This work carries significance in view of GBAS being planned at several low-latitude airports.展开更多
基金the project sponsored by Space Application Centre(SAC),Indian Space Research Organization(ISRO),Ahmedabad,vide sanction letter dated 23 Jan 2017(Project ID.NGP-11),under NAVICGAGAN Utilization programme.
文摘One of the significant features that makes Indian Regional Navigation Satellite System(IRNSS)distinct from most of the other satellite navigation systems is the use of S band signal along with the L-band signals.The fact that S-band signals experience lesser ionospheric delays and therefore lesser ionospheric gradients than L-band signals is of great advantage,more-so in ionospheric storm conditions.The advantage of using IRNSS S-band signal under ionospheric storm conditions for Ground Based Augmentation System(GBAS)applications is investigated in this paper.The analysis is carried out by computing a GBAS parameter namely sigma-vertical-ionospheric-gradient(σvig)using data from low-latitude stations in Hyderabad,India(17.3850°N,78.4867°E)under both quiet and storm ionospheric conditions and then estimating vertical protection levels(VPLs).It is observed that even in storm conditions,σvig is only 5.08 mm/km with S1 as against 22.80 mm/km due to L5.Also,the VPLs are 0.65 m less than those with L5 and are well within the alert limits.This work carries significance in view of GBAS being planned at several low-latitude airports.
