Multisource Self-calibration for Sensor Arrays
arXiv:1003.1892 · doi:10.1109/TSP.2009.2022894
Abstract
Calibration of a sensor array is more involved if the antennas have direction dependent gains and multiple calibrator sources are simultaneously present. We study this case for a sensor array with arbitrary geometry but identical elements, i.e. elements with the same direction dependent gain pattern. A weighted alternating least squares (WALS) algorithm is derived that iteratively solves for the direction independent complex gains of the array elements, their noise powers and their gains in the direction of the calibrator sources. An extension of the problem is the case where the apparent calibrator source locations are unknown, e.g., due to refractive propagation paths. For this case, the WALS method is supplemented with weighted subspace fitting (WSF) direction finding techniques. Using Monte Carlo simulations we demonstrate that both methods are asymptotically statistically efficient and converge within two iterations even in cases of low SNR.
11 pages, 8 figures
References in corpus (1)
Cited by in corpus (27)
- LOFAR: The LOw-Frequency ARray
- Observing pulsars and fast transients with LOFAR
- Calibration Requirements for Detecting the 21 cm Epoch of Reionization Power Spectrum and Implications for the SKA
- Systematic biases in low frequency radio interferometric data due to calibration: the LOFAR EoR case
- Calibration Challenges for Future Radio Telescopes
- Measuring a Cherenkov ring in the radio emission from air showers at 110-190 MHz with LOFAR
- Fast gain calibration in radio astronomy using alternating direction implicit methods: Analysis and applications
- Calibration artefacts in radio interferometry. I. Ghost sources in WSRT data
- Quantifying Suppression of the Cosmological 21-cm Signal due to Direction Dependent Gain Calibration in Radio Interferometers
- Robust Calibration of Radio Interferometers in Non-Gaussian Environment
- Redundancy Calibration of Phased Array Stations
- A Generic and Efficient E-field Parallel Imaging Correlator for Next-Generation Radio Telescopes
- Probing early universe through redshifted 21-cm signal: Modelling and observational challenges
- Calibration Requirements for Epoch of Reionization 21-cm signal observations -- I. Effect of time-correlated gains
- An Efficient Feedback Calibration Algorithm for Direct Imaging Radio Telescopes
- Asymptotically Optimal Blind Calibration of Uniform Linear Sensor Arrays for Narrowband Gaussian Signals
- The AARTFAAC 60 MHz transients survey
- Calibration requirements for Epoch of Reionization 21-cm signal observations -- II. Analytical estimation of the bias and variance with time-correlated residual gains
- Statistical Performance of Radio Interferometric Calibration
- Apparent radio transients mapping the near-Earth plasma environment
- A tensor model for the calibration of air-coupled ultrasonic sensor arrays in 3D imaging
- Self-Calibration of Radio Astronomical Arrays With Non-Diagonal Noise Covariance Matrix
- Parallel Calibration for Sensor Array Radio Interferometers
- Tied-array holography with LOFAR
- Robust distributed calibration of radio interferometers with direction dependent distortions
- Removing systematics-induced 21-cm foreground residuals by cross-correlating filtered data
- Self Calibration of Scalar and Vector Sensor Arrays