The Experts below are selected from a list of 13152 Experts worldwide ranked by ideXlab platform

Yeoujyh Tsai - One of the best experts on this subject based on the ideXlab platform.

  • wide area augmentation of the global positioning system
    Proceedings of the IEEE, 1996
    Co-Authors: Per Enge, Todd Walter, Sam Pullen, Changdon Kee, Yichung Chao, Yeoujyh Tsai
    Abstract:

    The Wide Area Augmentation System (WAAS) is being deployed by the Federal Aviation Administration (FAA) to augment the Global Positioning System (GPS). The WAAS will aid GPS with the following three services. First, it will broadcast spread-spectrum ranging signals from communication satellites. The airborne WAAS receiver will add these new ranging signals to the GPS constellation of measurements. By so doing, the augmented position fix will be less sensitive to the failure of individual system components, thus improving time availability and continuity of service. Second, the WAAS will use a nationwide ground network to monitor the health of all satellites over our airspace and flag situations which threaten flight safety. This data will be modulated on to the WAAS ranging signals and broadcast to the users, thereby guaranteeing the integrity of the airborne position fix. Third, the WAAS will use the ground network to develop corrections for the errors which currently limit the accuracy of unaugmented GPS. This data will also be included on the WAAS broadcast and will improve position accuracy from approximately 100 m to 8 m. When complete, the augmented system will provide an accurate position fix from satellites to an unlimited number of aircraft across the nation. It will be the Primary Navigation system for aircraft in oceanic routes, enroute over our domestic airspace, in crowded metropolitan airspaces, and on airport approach.

S C Rathnakara A S Ganeshan - One of the best experts on this subject based on the ideXlab platform.

  • Modernized IRNSS Broadcast Ephemeris Parameters
    Control Theory and Informatics, 2015
    Co-Authors: M V Chandrasekhar D.rajarajan, G Satyanarayana Neetha Tirmal, S C Rathnakara A S Ganeshan
    Abstract:

    India has successfully stepped into satellite Navigation system with the launch of its first three IRNSS satellites IRNSS 1A, 1B and 1C.  IRNSS provides two types of services, Standard Posting Service (SPS), which is open for civilian use and the Restricted Service (RS), for authorized users.  The system is set to change the facet of Navigation, surveying, transportation, precision agriculture, disaster management and telecommunication in India. In any Navigation system, broadcast Navigation parameters are of paramount importance in arriving user position solution at user receiver end. IRNSS Navigation data is classified as Primary and secondary Navigation parameters. Primary Navigation data of a satellite principally represents its own orbit and onboard clock offset in the form of quasi-keplerian elements and clock coefficients (Bias, Drift and Drifts rate) respectively. Whereas secondary Navigation parameters includes satellite almanac, ionosphere delay correction messages, differential corrections, Earth orientation parameters and  IRNSS Time offset with respect to other GNSS. In existing IRNSS system satellite ephemeris of Primary Navigation parameters are broadcast in the form of 15 quasi-keplerian elements valid for a period of 2 hours or more. Spacecraft ephemeris which represents orbit in the form of 9 parameters, i.e., position, velocity and acceleration component of spacecraft in Cartesian coordinate system are chosen from Russian Global Navigation satellite system (Glonass) to improve Time to First Fix (TTFF) of IRNSS system with similar existing orbit accuracy. In addition, two models of user receiver orbit propagation algorithms with proposed ephemeris are briefed and their results are compared with standalone Glonass model. Generation of IRNSS ephemeris in Cartesian coordinate system and description of user receiver orbit propagation algorithms using new type of ephemeris to get user position solution is the scope of this paper.. Keywords: IRNSS, TTFF (Time to First Fix), Broadcast ephemeris

A S Ganeshan - One of the best experts on this subject based on the ideXlab platform.

  • Modernized IRNSS Broadcast Ephemeris Parameters
    2016
    Co-Authors: M V Chandrasekhar, S C Rathnakara, Rajarajan D. G Satyanarayana, Neetha Tirmal, A S Ganeshan
    Abstract:

    India has successfully stepped into satellite Navigation system with the launch of its first three IRNSS satellites IRNSS 1A, 1B and 1C. IRNSS provides two types of services, Standard Posting Service (SPS), which is open for civilian use and the Restricted Service (RS), for authorized users. The system is set to change the facet of Navigation, surveying, transportation, precision agriculture, disaster management and telecommunication in India. In any Navigation system, broadcast Navigation parameters are of paramount importance in arriving user position solution at user receiver end. IRNSS Navigation data is classified as Primary and secondary Navigation parameters. Primary Navigation data of a satellite principally represents its own orbit and onboard clock offset in the form of quasi-keplerian elements and clock coefficients (Bias, Drift and Drifts rate) respectively. Whereas secondary Navigation parameters includes satellite almanac, ionosphere delay correction messages, differential corrections, Earth orientation parameters and IRNSS Time offset with respect to other GNSS. In existing IRNSS system satellite ephemeris of Primary Navigation parameters are broadcast in the form of 15 quasi-keplerian elements valid for a period of 2 hours or more. Spacecraft ephemeris which represents orbit in the form of 9 parameters, i.e., position, velocity and acceleration component of spacecraft in Cartesian coordinate system are chosen from Russian Global Navigation satellite system (Glonass) to improve Time to First Fix (TTFF) o

Per Enge - One of the best experts on this subject based on the ideXlab platform.

  • wide area augmentation of the global positioning system
    Proceedings of the IEEE, 1996
    Co-Authors: Per Enge, Todd Walter, Sam Pullen, Changdon Kee, Yichung Chao, Yeoujyh Tsai
    Abstract:

    The Wide Area Augmentation System (WAAS) is being deployed by the Federal Aviation Administration (FAA) to augment the Global Positioning System (GPS). The WAAS will aid GPS with the following three services. First, it will broadcast spread-spectrum ranging signals from communication satellites. The airborne WAAS receiver will add these new ranging signals to the GPS constellation of measurements. By so doing, the augmented position fix will be less sensitive to the failure of individual system components, thus improving time availability and continuity of service. Second, the WAAS will use a nationwide ground network to monitor the health of all satellites over our airspace and flag situations which threaten flight safety. This data will be modulated on to the WAAS ranging signals and broadcast to the users, thereby guaranteeing the integrity of the airborne position fix. Third, the WAAS will use the ground network to develop corrections for the errors which currently limit the accuracy of unaugmented GPS. This data will also be included on the WAAS broadcast and will improve position accuracy from approximately 100 m to 8 m. When complete, the augmented system will provide an accurate position fix from satellites to an unlimited number of aircraft across the nation. It will be the Primary Navigation system for aircraft in oceanic routes, enroute over our domestic airspace, in crowded metropolitan airspaces, and on airport approach.

M V Chandrasekhar D.rajarajan - One of the best experts on this subject based on the ideXlab platform.

  • Modernized IRNSS Broadcast Ephemeris Parameters
    Control Theory and Informatics, 2015
    Co-Authors: M V Chandrasekhar D.rajarajan, G Satyanarayana Neetha Tirmal, S C Rathnakara A S Ganeshan
    Abstract:

    India has successfully stepped into satellite Navigation system with the launch of its first three IRNSS satellites IRNSS 1A, 1B and 1C.  IRNSS provides two types of services, Standard Posting Service (SPS), which is open for civilian use and the Restricted Service (RS), for authorized users.  The system is set to change the facet of Navigation, surveying, transportation, precision agriculture, disaster management and telecommunication in India. In any Navigation system, broadcast Navigation parameters are of paramount importance in arriving user position solution at user receiver end. IRNSS Navigation data is classified as Primary and secondary Navigation parameters. Primary Navigation data of a satellite principally represents its own orbit and onboard clock offset in the form of quasi-keplerian elements and clock coefficients (Bias, Drift and Drifts rate) respectively. Whereas secondary Navigation parameters includes satellite almanac, ionosphere delay correction messages, differential corrections, Earth orientation parameters and  IRNSS Time offset with respect to other GNSS. In existing IRNSS system satellite ephemeris of Primary Navigation parameters are broadcast in the form of 15 quasi-keplerian elements valid for a period of 2 hours or more. Spacecraft ephemeris which represents orbit in the form of 9 parameters, i.e., position, velocity and acceleration component of spacecraft in Cartesian coordinate system are chosen from Russian Global Navigation satellite system (Glonass) to improve Time to First Fix (TTFF) of IRNSS system with similar existing orbit accuracy. In addition, two models of user receiver orbit propagation algorithms with proposed ephemeris are briefed and their results are compared with standalone Glonass model. Generation of IRNSS ephemeris in Cartesian coordinate system and description of user receiver orbit propagation algorithms using new type of ephemeris to get user position solution is the scope of this paper.. Keywords: IRNSS, TTFF (Time to First Fix), Broadcast ephemeris