The University of Southampton
University of Southampton Institutional Repository

Phase and baseline calibration for microwave interferometric radiometers using beacons

Phase and baseline calibration for microwave interferometric radiometers using beacons
Phase and baseline calibration for microwave interferometric radiometers using beacons
Relative phase and amplitude calibration between individual receiving elements is one of the key challenges in interferometric microwave radiometry. For monolithic interferometers, e.g., the Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) on board the Soil Moisture and Ocean Salinity (SMOS) mission, the calibration of these two parameters is accomplished by correlated noise injection, where a noise signal from a central noise source is distributed to multiple elements in phase, and any measured phase and amplitude differences can be measured and compensated. As new multi-satellite interferometers are being proposed, a new strategy capable of calibrating these errors between the free-flying antennas as well as any antenna position errors is required. In this work, a new calibration scheme is proposed which uses a set of microwave beacons in place of the central noise source, placed at known locations within the interferometer’s field of view. The visibility function produced by these point-sources can be pre-calculated, and any errors between the calculated and the measured visibility samples can be attributed to the errors to be determined. Since the phase of the measured visibility is a function of phase and antenna position errors, this technique is capable of calibrating these two parameters simultaneously. Calibration equations for far- and near-field beacons are presented. Using these expressions, five interferometric calibration routines are proposed and examined for geostationary formation flight microwave radiometers. While this technique is ideal for multi-satellite interferometers with variable antenna positions, it is also applicable to monolithic interferometers that can undergo substantial array deformation.
0196-2892
Sugihara El Maghraby, Ahmed Kiyoshi
2908d60c-5467-460b-b1a4-b76ea694f453
Park, Hyuk
f36e1bb5-e2fe-4fcd-80c7-d423f09da87b
Camps, Adriano
99a7e182-48de-4b44-9862-d78eda637336
Grubisic, Angelo
a4cab763-bbc0-4130-af65-229ae674e8c8
Colombo, Camilla
595ced96-9494-40f2-9763-ad4a0f96bc86
Tatnall, Adrian
2c9224b6-4faa-4bfd-9026-84e37fa6bdf3
Sugihara El Maghraby, Ahmed Kiyoshi
2908d60c-5467-460b-b1a4-b76ea694f453
Park, Hyuk
f36e1bb5-e2fe-4fcd-80c7-d423f09da87b
Camps, Adriano
99a7e182-48de-4b44-9862-d78eda637336
Grubisic, Angelo
a4cab763-bbc0-4130-af65-229ae674e8c8
Colombo, Camilla
595ced96-9494-40f2-9763-ad4a0f96bc86
Tatnall, Adrian
2c9224b6-4faa-4bfd-9026-84e37fa6bdf3

Sugihara El Maghraby, Ahmed Kiyoshi, Park, Hyuk, Camps, Adriano, Grubisic, Angelo, Colombo, Camilla and Tatnall, Adrian (2019) Phase and baseline calibration for microwave interferometric radiometers using beacons. IEEE Transactions on Geoscience and Remote Sensing. (Submitted)

Record type: Article

Abstract

Relative phase and amplitude calibration between individual receiving elements is one of the key challenges in interferometric microwave radiometry. For monolithic interferometers, e.g., the Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) on board the Soil Moisture and Ocean Salinity (SMOS) mission, the calibration of these two parameters is accomplished by correlated noise injection, where a noise signal from a central noise source is distributed to multiple elements in phase, and any measured phase and amplitude differences can be measured and compensated. As new multi-satellite interferometers are being proposed, a new strategy capable of calibrating these errors between the free-flying antennas as well as any antenna position errors is required. In this work, a new calibration scheme is proposed which uses a set of microwave beacons in place of the central noise source, placed at known locations within the interferometer’s field of view. The visibility function produced by these point-sources can be pre-calculated, and any errors between the calculated and the measured visibility samples can be attributed to the errors to be determined. Since the phase of the measured visibility is a function of phase and antenna position errors, this technique is capable of calibrating these two parameters simultaneously. Calibration equations for far- and near-field beacons are presented. Using these expressions, five interferometric calibration routines are proposed and examined for geostationary formation flight microwave radiometers. While this technique is ideal for multi-satellite interferometers with variable antenna positions, it is also applicable to monolithic interferometers that can undergo substantial array deformation.

Text
TGRS-2018_Sugihara - Author's Original
Download (5MB)

More information

Submitted date: 21 January 2019

Identifiers

Local EPrints ID: 429067
URI: http://eprints.soton.ac.uk/id/eprint/429067
ISSN: 0196-2892
PURE UUID: 5d3aca6b-9679-4062-a834-08b7c17a265b
ORCID for Ahmed Kiyoshi Sugihara El Maghraby: ORCID iD orcid.org/0000-0001-9183-1317
ORCID for Camilla Colombo: ORCID iD orcid.org/0000-0001-9636-9360

Catalogue record

Date deposited: 20 Mar 2019 17:30
Last modified: 27 Jan 2020 13:30

Export record

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×