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Emilio G. Piracci - One of the best experts on this subject based on the ideXlab platform.

  • Separation of SSR Signals by Array Processing in Multilateration Systems
    IEEE Transactions on Aerospace and Electronic Systems, 2009
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Location and identification of cooperating aircraft in the airport area (and beyond) may be implemented by multilateration (MLAT) systems using the Secondary Surveillance Radar (SSR) Mode S signals. Most of these signals, spontaneously emitted from on-board Mode S transponders at a fixed carrier frequency, arrive randomly at the receiving station, as well as many Mode A/C replies from legacy transponders still in use. Several SSR signals are, then, overlapped in multiple aircraft situations. Therefore, the aim of this work is the separation of overlapped SSR signals, i.e. signals superimposed in time at receiving stations. We improve the MLAT receiving station by replacing the single antenna by an array of m elements and using array signal processing techniques. In the literature, several algorithms address the general source separation problem, but a very few of them are specifically designed for a mixture of overlapping SSR replies. Unfortunately, all of them have either some shortcomings, or an expensive computational cost, or no simple practical implementation. In this paper, we use the time sparsity property of the sources to propose more reliable, simpler, and more effective algorithms based on projection techniques to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of our method.

  • Secondary Surveillance Radar: Sparsity-based sources separation in a real Environment
    2008 Tyrrhenian International Workshop on Digital Communications - Enhanced Surveillance of Aircraft and Vehicles, 2008
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today [1], [2]. We proposed several new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works [3], [4], [5], [6], other solutions were also proposed in the literature [7], [8], [9]. Unfortunately, a rare event, but important, has not yet been resolved: the impinging of more sources than sensors with an approximate similar time of arrival. This preliminary work studies the use of the SSR sources sparsity property, as in [10], [11], [12]. Real recorded signals in a Live Environment will be used to demonstrate the effectiveness of the proposed techniques.

  • separation of multiple secondary surveillance radar sources in a real Environment by a novel projection algorithm
    International Symposium on Signal Processing and Information Technology, 2005
    Co-Authors: N. Petrochilos, Gaspare Galati, L. Mene, Emilio G. Piracci
    Abstract:

    Multilateration systems based on secondary surveillance radar (SSR) and omni-directional antennae are operational today (P. Bezousek, 1998) with expected capacity limitations due to the increase of the air traffic. Assuming the replacement of the omni-directional antenna by an array, we proposed new algorithms in previous works (N. Petrochilos, July 2002), (N. Petrochilos, et al., May 2004). Unfortunately, they have some shortcomings, an expensive computational cost, and a not-so simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms such as the one we present here to separate multiple SSR signals. Real signals (as recorded in a Live Environment) are used to demonstrate the effectiveness of the proposed algorithm

  • Projection Techniques for Separation of Multiple Secondary Surveillance Radar Sources in a Real Environment
    Fourth IEEE Workshop on Sensor Array and Multichannel Processing 2006., 1
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today. We proposed new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works, other solutions were also proposed in the literature. Unfortunately, all have either some shortcomings, or an expensive computational cost, or no simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of the proposed techniques

N. Petrochilos - One of the best experts on this subject based on the ideXlab platform.

  • Separation of SSR Signals by Array Processing in Multilateration Systems
    IEEE Transactions on Aerospace and Electronic Systems, 2009
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Location and identification of cooperating aircraft in the airport area (and beyond) may be implemented by multilateration (MLAT) systems using the Secondary Surveillance Radar (SSR) Mode S signals. Most of these signals, spontaneously emitted from on-board Mode S transponders at a fixed carrier frequency, arrive randomly at the receiving station, as well as many Mode A/C replies from legacy transponders still in use. Several SSR signals are, then, overlapped in multiple aircraft situations. Therefore, the aim of this work is the separation of overlapped SSR signals, i.e. signals superimposed in time at receiving stations. We improve the MLAT receiving station by replacing the single antenna by an array of m elements and using array signal processing techniques. In the literature, several algorithms address the general source separation problem, but a very few of them are specifically designed for a mixture of overlapping SSR replies. Unfortunately, all of them have either some shortcomings, or an expensive computational cost, or no simple practical implementation. In this paper, we use the time sparsity property of the sources to propose more reliable, simpler, and more effective algorithms based on projection techniques to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of our method.

  • Secondary Surveillance Radar: Sparsity-based sources separation in a real Environment
    2008 Tyrrhenian International Workshop on Digital Communications - Enhanced Surveillance of Aircraft and Vehicles, 2008
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today [1], [2]. We proposed several new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works [3], [4], [5], [6], other solutions were also proposed in the literature [7], [8], [9]. Unfortunately, a rare event, but important, has not yet been resolved: the impinging of more sources than sensors with an approximate similar time of arrival. This preliminary work studies the use of the SSR sources sparsity property, as in [10], [11], [12]. Real recorded signals in a Live Environment will be used to demonstrate the effectiveness of the proposed techniques.

  • separation of multiple secondary surveillance radar sources in a real Environment by a novel projection algorithm
    International Symposium on Signal Processing and Information Technology, 2005
    Co-Authors: N. Petrochilos, Gaspare Galati, L. Mene, Emilio G. Piracci
    Abstract:

    Multilateration systems based on secondary surveillance radar (SSR) and omni-directional antennae are operational today (P. Bezousek, 1998) with expected capacity limitations due to the increase of the air traffic. Assuming the replacement of the omni-directional antenna by an array, we proposed new algorithms in previous works (N. Petrochilos, July 2002), (N. Petrochilos, et al., May 2004). Unfortunately, they have some shortcomings, an expensive computational cost, and a not-so simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms such as the one we present here to separate multiple SSR signals. Real signals (as recorded in a Live Environment) are used to demonstrate the effectiveness of the proposed algorithm

  • Projection Techniques for Separation of Multiple Secondary Surveillance Radar Sources in a Real Environment
    Fourth IEEE Workshop on Sensor Array and Multichannel Processing 2006., 1
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today. We proposed new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works, other solutions were also proposed in the literature. Unfortunately, all have either some shortcomings, or an expensive computational cost, or no simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of the proposed techniques

Gaspare Galati - One of the best experts on this subject based on the ideXlab platform.

  • Separation of SSR Signals by Array Processing in Multilateration Systems
    IEEE Transactions on Aerospace and Electronic Systems, 2009
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Location and identification of cooperating aircraft in the airport area (and beyond) may be implemented by multilateration (MLAT) systems using the Secondary Surveillance Radar (SSR) Mode S signals. Most of these signals, spontaneously emitted from on-board Mode S transponders at a fixed carrier frequency, arrive randomly at the receiving station, as well as many Mode A/C replies from legacy transponders still in use. Several SSR signals are, then, overlapped in multiple aircraft situations. Therefore, the aim of this work is the separation of overlapped SSR signals, i.e. signals superimposed in time at receiving stations. We improve the MLAT receiving station by replacing the single antenna by an array of m elements and using array signal processing techniques. In the literature, several algorithms address the general source separation problem, but a very few of them are specifically designed for a mixture of overlapping SSR replies. Unfortunately, all of them have either some shortcomings, or an expensive computational cost, or no simple practical implementation. In this paper, we use the time sparsity property of the sources to propose more reliable, simpler, and more effective algorithms based on projection techniques to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of our method.

  • Secondary Surveillance Radar: Sparsity-based sources separation in a real Environment
    2008 Tyrrhenian International Workshop on Digital Communications - Enhanced Surveillance of Aircraft and Vehicles, 2008
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    Secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today [1], [2]. We proposed several new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works [3], [4], [5], [6], other solutions were also proposed in the literature [7], [8], [9]. Unfortunately, a rare event, but important, has not yet been resolved: the impinging of more sources than sensors with an approximate similar time of arrival. This preliminary work studies the use of the SSR sources sparsity property, as in [10], [11], [12]. Real recorded signals in a Live Environment will be used to demonstrate the effectiveness of the proposed techniques.

  • separation of multiple secondary surveillance radar sources in a real Environment by a novel projection algorithm
    International Symposium on Signal Processing and Information Technology, 2005
    Co-Authors: N. Petrochilos, Gaspare Galati, L. Mene, Emilio G. Piracci
    Abstract:

    Multilateration systems based on secondary surveillance radar (SSR) and omni-directional antennae are operational today (P. Bezousek, 1998) with expected capacity limitations due to the increase of the air traffic. Assuming the replacement of the omni-directional antenna by an array, we proposed new algorithms in previous works (N. Petrochilos, July 2002), (N. Petrochilos, et al., May 2004). Unfortunately, they have some shortcomings, an expensive computational cost, and a not-so simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms such as the one we present here to separate multiple SSR signals. Real signals (as recorded in a Live Environment) are used to demonstrate the effectiveness of the proposed algorithm

  • Projection Techniques for Separation of Multiple Secondary Surveillance Radar Sources in a Real Environment
    Fourth IEEE Workshop on Sensor Array and Multichannel Processing 2006., 1
    Co-Authors: N. Petrochilos, Gaspare Galati, Emilio G. Piracci
    Abstract:

    secondary surveillance radar (SSR) based on multilateration principle and omni-directional antennae are operational today. We proposed new algorithms to separate a mixture of overlapping SSR replies on a M-elements antenna in previous works, other solutions were also proposed in the literature. Unfortunately, all have either some shortcomings, or an expensive computational cost, or no simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms to separate multiple SSR signals. Real recorded signals in a Live Environment are used to demonstrate the effectiveness of the proposed techniques

Mohammad Davarpanah Jazi - One of the best experts on this subject based on the ideXlab platform.

  • Constructing user requirements: a social process for a social context
    Information Systems Journal, 1998
    Co-Authors: Donal J. Flynn, Mohammad Davarpanah Jazi
    Abstract:

    We discuss our approach to constructing user requirements whereby users build requirements models themselves. The approach, termed user-led requirements construction (ULRC), is a social process that addresses a major problem: the user-developer culture gap. An important feature of the approach is that we have conducted, with users, an interpretivist empirical evaluation study of its constituent event flow diagram (EFD) modelling method and associated training. The ULRC has also been used in a Live Environment. The results are that users regard the EFD as effective for the requirements process, the EFD may be used for further studies to deepen our knowledge of the requirements process and the results contribute towards a set of public results for general evaluation and improvement.

L. Mene - One of the best experts on this subject based on the ideXlab platform.

  • separation of multiple secondary surveillance radar sources in a real Environment by a novel projection algorithm
    International Symposium on Signal Processing and Information Technology, 2005
    Co-Authors: N. Petrochilos, Gaspare Galati, L. Mene, Emilio G. Piracci
    Abstract:

    Multilateration systems based on secondary surveillance radar (SSR) and omni-directional antennae are operational today (P. Bezousek, 1998) with expected capacity limitations due to the increase of the air traffic. Assuming the replacement of the omni-directional antenna by an array, we proposed new algorithms in previous works (N. Petrochilos, July 2002), (N. Petrochilos, et al., May 2004). Unfortunately, they have some shortcomings, an expensive computational cost, and a not-so simple practical implementation. Therefore, there is a need for reliable, simple, effective algorithms such as the one we present here to separate multiple SSR signals. Real signals (as recorded in a Live Environment) are used to demonstrate the effectiveness of the proposed algorithm

  • Analysis of SSR signals by super resolution algorithms
    Proceedings of the Fourth IEEE International Symposium on Signal Processing and Information Technology 2004., 1
    Co-Authors: G. Galati, S. Bartolini, L. Mene
    Abstract:

    A new method for SSR (secondary surveillance radar) signal analysis, in particular SSR Mode S replies, can be obtained exploiting the super resolution algorithms capability to discriminate signals in the frequency domain. This work summarises the results obtained by the application of Tufts-Kumaresan, Music, Esprit and Unitary Esprit algorithms to decode Mode S replies and squitters acquired in a Live Environment. Hence, we propose 16 possible processing schemes which, compared to conventional schemes, have shown sensible improvements. It results that the main limit is represented by the quality of the on board transponder local oscillator which causes a too small spectral separation between two overlapped signals.