
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:title>Ground Monitors to Support Navigation Operations of ARAIM and GBAS</dc:title>
  <dc:creator>Patel, Jaymin Harshadkumar</dc:creator>
  <dc:subject>Aerospace engineering</dc:subject>
  <dc:subject>ARAIM</dc:subject>
  <dc:subject>clocks</dc:subject>
  <dc:subject>GBAS</dc:subject>
  <dc:subject>Global positioning system</dc:subject>
  <dc:subject>ionospheric faults</dc:subject>
  <dc:subject>orbits</dc:subject>
  <dc:description>Receiver Autonomous Integrity Monitoring (RAIM) currently provides safehorizontal navigation guidance to en route civil aircraft using the GPS L1 frequency.
As an evolution of RAIM, Advanced RAIM (ARAIM) is being developed to provide
vertical guidance in addition to horizontal using multiple constellations and dual frequency
thus facilitating precision approach without ground support for civil aircraft.
However, navigation guidance during zero-visibility (Category III) precision landing
requires an additional support in real time from a Ground Based Augmentation
System (GBAS). To improve the aircraft navigation solution, GBAS broadcasts a
differential correction and monitors any failure on transmitted satellite signals. This
dissertation contributes to ARAIM and GBAS to improve existing navigation operations
in order to enable precision approach and landing.The achievable performance of ARAIM is highly dependent on the assumptionson a constellation’s nominal Signal-In-Space (SIS) error models and a priori
fault probability. In the framework of ARAIM, an Integrity Support Message (ISM)
is envisioned to carry the required SIS error-model parameters and fault statistics
for users. The ISM is generated and validated through offline monitoring, and disseminated
along the navigation message. The first dissertation contribution is to
provide necessary satellite positions and clock biases as a truth product to evaluate
nominal SIS range errors (SISREs). An estimator is developed to generate accurate
ephemeris parameters to provide these truth products. The estimator’s performance
is demonstrated for the Global Positioning System (GPS) constellation by utilizing
the International GNSS Service (IGS) ground network to collect dual-frequency raw
GPS code and carrier phase measurements. The resulting SISREs from the estimator
are predicted to have a standard deviation of 0.5 m. When estimated ephemeris
parameters and clock biases are compared with precise IGS orbit and clock products, the resulting SISREs are within ±2! at all times. In the second contribution,
a new approach is proposed to generate the ISM by modeling the ephemeris parameter
errors directly. In preliminary analysis, an ephemeris parameter error model is
developed for the broadcast GPS legacy navigation message (LNAV) under nominal
conditions. Then, the proposed approach is demonstrated to provide the nominal
bias and standard deviation on GPS SISREs.As a part of fault monitoring in the GBAS, a ground monitor is developedto detect ephemeris failures, incorrect broadcast satellite positions, and hazardous
ionosphere storms using either single- or dual frequency. The monitor also addresses
the challenge of fault-free differential correction when satellites are rising, newly acquired,
and re-acquired. The monitor utilizes differential code and carrier phase
measurements across multiple reference receiver antennas as the basis for detection.
Finally, the analytical performance of the monitor is demonstrated to meet Category
III precision approach and landing requirements.</dc:description>
  <dc:contributor>Pervan, Boris S.</dc:contributor>
  <dc:date>2023</dc:date>
  <dc:type>Dissertation</dc:type>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>islandora:1025154</dc:identifier>
  <dc:identifier>http://hdl.handle.net/10560/islandora:1025154</dc:identifier>
  <dc:source></dc:source>
  <dc:source>Illinois Institute of Technology</dc:source>
  <dc:source>MMAE / Mechanical, Materials, and Aerospace Engineering</dc:source>
  <dc:source></dc:source>
  <dc:language>en</dc:language>
  <dc:rights>In
                Copyright</dc:rights>
  <dc:rights>http://rightsstatements.org/page/InC/1.0/</dc:rights>
  <dc:rights>Restricted Access</dc:rights>
</oai_dc:dc>
