This paper deals with a Software Defined Radio (SDR) receiver capable to process GPS and Galileo ... more This paper deals with a Software Defined Radio (SDR) receiver capable to process GPS and Galileo signals jointly. A large set of possible solution can be implemented, with the main aim of assessing the performance of the receiver for the considered architectures. For this reason, software receivers, either real-time or non-real-time, are fundamental tools to enable research and new developments in the field of GNSSs. In this paper our intent is to discuss some of the choices one can face when implementing an SDR GNSS receiver, switching from the theory to the practice. We focus our attention on the pseudorange construction and the Position, Velocity and Time (PVT) estimation stage, discussing different algorithms to implement these blocks. Our aim is to offer an insight on the options to implement those stages of the receiving chain, in a practical vision which is difficult to find in the available literature.
This paper shows the design and development of a truly low cost attitude determination and naviga... more This paper shows the design and development of a truly low cost attitude determination and navigation system based primarily on non-dedicated mass market GNSS receivers and antennas, aided by MEMS inertial sensors. GNSS/INS integration combines the advantages of absolute satellite-based positioning with the high dynamic performance and data rates of inertial sensors, having become the standard approach in navigation systems for Unmanned Aerial Vehicles (UAV) among other applications. We have used a Tightly-Coupled (TC) algorithm aimed at the integration of GPS and INS devices, designed to exploit the measurements provided by four GNSS receivers and a MEMS IMU. This task is accomplished by forming double differences (DD) of carrier-phase measurements and properly solving the ambiguities on-the-fly. The robustness of the algorithm is enhanced by exploiting unambiguous DD of code-phase observables or un-differenced pseudoranges when carrier phase ambiguity fix is not reliable. In order...
U nmanned aerial vehicles (UAV) are finding increased application in both domestic and government... more U nmanned aerial vehicles (UAV) are finding increased application in both domestic and governmental applications. Small UAVs (maximum take off weight less than 20 kilograms) comprise the category of the smallest and lightest platforms that also fly at lower altitudes (under less than 150 meters). Designs for this class of device have focused on creating UAVs that can operate in urban canyons or even inside buildings, fly along hallways, and carry listening and recording devices, transmitters , or miniature TV cameras. Operational requirements for these kinds of UAVs typically encompass flying close to the ground and in relatively narrow spaces with a lot of obstacles. This introduces problems for a simplistic application of technologies used in larger UAVs. In particular, the rotary wing UAV platforms used in those scenarios provide vertical takeoff and landing and hovering capability, but they are intrinsically unstable systems requiring high-rate and accurate attitude and position...
The advent of the first two satellites of the final Galileo constellation launched by Soyuz from ... more The advent of the first two satellites of the final Galileo constellation launched by Soyuz from Europe’s spaceport in French Guiana on October 21st is a major milestone for the European as well as global satellite navigation field. In fact, these two satellites pave the way for a much awaited set of experiments testing the benefits brought about by an additional constellation in orbit, Galileo. The European constellation formed by last generation satellites carrying very precise hydrogen maser clocks, and transmitting sophisticated navigation payloads, is expected to increase positioning availability and improve satellite geometry so far as to decrease positioning errors with respect to the use of GPS satellites exclusively. In this paper, signal acquisition, tracking and demodulation of the signal broadcast by the first Galileo satellite (the so-called IOV-PFM Galileo satellite) in the E1 bandwidth is performed. Starting to monitor this satellite from December 2011, we were able t...
2012 IEEE International Geoscience and Remote Sensing Symposium, 2012
ABSTRACT As more and more attention is received by the underlying passive potential of Global Nav... more ABSTRACT As more and more attention is received by the underlying passive potential of Global Navigation Satellite Systems (GNSS) signals, reflectometry and scatterometry are visited in this paper in order to assess water surface identification and aircraft altimetry performance. This is possible thanks to the high reflectivity of Global Positioning System (GPS) signals in the L-Band frequency range on water as well as ice and snow covered surfaces which compensates for the otherwise low signal intensity. Indeed, GNSS reflectometry belongs to the class of bistatic radar systems where transmitter and receiver reside at different locations and signals pass through a reflecting surface. Code phase and carrier phase based time delay measurements between the direct path and reflected signals, are used to determine the small aircraft's height with respect to the reflecting surface. On the other hand, specular reflection points are computed, and a comparison of the reflected power to the direct received power is shown to yield a good water surface identification performance. Code and carrier phase measurements are implemented in this paper to obtain cm level height estimates.
The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combin... more The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combination to overcome the limits of INS only and have a reduced error in position, velocity and attitude computation. We explore the feasibility of an integrated positioning system using a Differential GPS (DGPS) and an Inertial Navigation System (INS). The work is aimed at a development of a low-cost multi sensor device that will equip every machine and vehicle in a coal mining in order to monitor their movements in real time and avoid possible ...
The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combin... more The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combination to overcome the limits of INS only and have a reduced error in position, velocity and attitude computation. Accurate analysis of inertial sensor error is essential to ensuring the effectiveness of the optimal GPS/INS integration and set the states variables of a Kalman filter properly. In this paper Allan Variance has been selected as the technique to investigate all the types of noise in a low-cost IMU system. The work at first presents the details of this ...
Europe's GNSS program-Galileo-entered a new phase of development with the recent launch of t... more Europe's GNSS program-Galileo-entered a new phase of development with the recent launch of two in-orbit validation satellites, which comprise the first elements of the system's full operational constellation. In this article, a team of italian researchers present the initial results of their analysis of the Galileo signals
This paper deals with a Software Defined Radio (SDR) receiver capable to process GPS and Galileo ... more This paper deals with a Software Defined Radio (SDR) receiver capable to process GPS and Galileo signals jointly. A large set of possible solution can be implemented, with the main aim of assessing the performance of the receiver for the considered architectures. For this reason, software receivers, either real-time or non-real-time, are fundamental tools to enable research and new developments in the field of GNSSs. In this paper our intent is to discuss some of the choices one can face when implementing an SDR GNSS receiver, switching from the theory to the practice. We focus our attention on the pseudorange construction and the Position, Velocity and Time (PVT) estimation stage, discussing different algorithms to implement these blocks. Our aim is to offer an insight on the options to implement those stages of the receiving chain, in a practical vision which is difficult to find in the available literature.
This paper shows the design and development of a truly low cost attitude determination and naviga... more This paper shows the design and development of a truly low cost attitude determination and navigation system based primarily on non-dedicated mass market GNSS receivers and antennas, aided by MEMS inertial sensors. GNSS/INS integration combines the advantages of absolute satellite-based positioning with the high dynamic performance and data rates of inertial sensors, having become the standard approach in navigation systems for Unmanned Aerial Vehicles (UAV) among other applications. We have used a Tightly-Coupled (TC) algorithm aimed at the integration of GPS and INS devices, designed to exploit the measurements provided by four GNSS receivers and a MEMS IMU. This task is accomplished by forming double differences (DD) of carrier-phase measurements and properly solving the ambiguities on-the-fly. The robustness of the algorithm is enhanced by exploiting unambiguous DD of code-phase observables or un-differenced pseudoranges when carrier phase ambiguity fix is not reliable. In order...
U nmanned aerial vehicles (UAV) are finding increased application in both domestic and government... more U nmanned aerial vehicles (UAV) are finding increased application in both domestic and governmental applications. Small UAVs (maximum take off weight less than 20 kilograms) comprise the category of the smallest and lightest platforms that also fly at lower altitudes (under less than 150 meters). Designs for this class of device have focused on creating UAVs that can operate in urban canyons or even inside buildings, fly along hallways, and carry listening and recording devices, transmitters , or miniature TV cameras. Operational requirements for these kinds of UAVs typically encompass flying close to the ground and in relatively narrow spaces with a lot of obstacles. This introduces problems for a simplistic application of technologies used in larger UAVs. In particular, the rotary wing UAV platforms used in those scenarios provide vertical takeoff and landing and hovering capability, but they are intrinsically unstable systems requiring high-rate and accurate attitude and position...
The advent of the first two satellites of the final Galileo constellation launched by Soyuz from ... more The advent of the first two satellites of the final Galileo constellation launched by Soyuz from Europe’s spaceport in French Guiana on October 21st is a major milestone for the European as well as global satellite navigation field. In fact, these two satellites pave the way for a much awaited set of experiments testing the benefits brought about by an additional constellation in orbit, Galileo. The European constellation formed by last generation satellites carrying very precise hydrogen maser clocks, and transmitting sophisticated navigation payloads, is expected to increase positioning availability and improve satellite geometry so far as to decrease positioning errors with respect to the use of GPS satellites exclusively. In this paper, signal acquisition, tracking and demodulation of the signal broadcast by the first Galileo satellite (the so-called IOV-PFM Galileo satellite) in the E1 bandwidth is performed. Starting to monitor this satellite from December 2011, we were able t...
2012 IEEE International Geoscience and Remote Sensing Symposium, 2012
ABSTRACT As more and more attention is received by the underlying passive potential of Global Nav... more ABSTRACT As more and more attention is received by the underlying passive potential of Global Navigation Satellite Systems (GNSS) signals, reflectometry and scatterometry are visited in this paper in order to assess water surface identification and aircraft altimetry performance. This is possible thanks to the high reflectivity of Global Positioning System (GPS) signals in the L-Band frequency range on water as well as ice and snow covered surfaces which compensates for the otherwise low signal intensity. Indeed, GNSS reflectometry belongs to the class of bistatic radar systems where transmitter and receiver reside at different locations and signals pass through a reflecting surface. Code phase and carrier phase based time delay measurements between the direct path and reflected signals, are used to determine the small aircraft's height with respect to the reflecting surface. On the other hand, specular reflection points are computed, and a comparison of the reflected power to the direct received power is shown to yield a good water surface identification performance. Code and carrier phase measurements are implemented in this paper to obtain cm level height estimates.
The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combin... more The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combination to overcome the limits of INS only and have a reduced error in position, velocity and attitude computation. We explore the feasibility of an integrated positioning system using a Differential GPS (DGPS) and an Inertial Navigation System (INS). The work is aimed at a development of a low-cost multi sensor device that will equip every machine and vehicle in a coal mining in order to monitor their movements in real time and avoid possible ...
The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combin... more The accuracy of INS degrades with time and therefore GPS/INS integration provides an ideal combination to overcome the limits of INS only and have a reduced error in position, velocity and attitude computation. Accurate analysis of inertial sensor error is essential to ensuring the effectiveness of the optimal GPS/INS integration and set the states variables of a Kalman filter properly. In this paper Allan Variance has been selected as the technique to investigate all the types of noise in a low-cost IMU system. The work at first presents the details of this ...
Europe's GNSS program-Galileo-entered a new phase of development with the recent launch of t... more Europe's GNSS program-Galileo-entered a new phase of development with the recent launch of two in-orbit validation satellites, which comprise the first elements of the system's full operational constellation. In this article, a team of italian researchers present the initial results of their analysis of the Galileo signals
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Papers by Gianluca Falco