Mr. Alexis Tejada Profile

Alexis Tejada

at Princetel Inc

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 23 July 2014 Paper

Detecting loss of coherence based on telescope calibration results in ALMA

A. Saez, A. Tejada, D. Herrera, Jorge Sepulveda

Proceedings Volume 9153, 91532I (2014) https://doi.org/10.1117/12.2056298

KEYWORDS: Calibration, Antennas, Telescopes, X band, Signal attenuation, Polarization, Error analysis, Signal detection, Signal processing, Fused deposition modeling

Read Abstract +

The ALMA telescope will be composed of 66 high precision antennas; each antenna producing 8 times 2GHz bandwidth signals (4 pairs or orthogonal linear polarizations signals). Detecting the root cause of a loss of coherence issue between pairs of antennas can take valuable time which could be used for scientific purposes. This work presents an approach for quickly determining, in a systematic fashion, the source of this kind of issues. Faulty sub-system can be detected using the telescope calibration software and the granularity information. In a complex instrument such as the ALMA telescope, finding the cause of a loss of coherence issue can be a cumbersome task due to the several sub-systems involved on the signal processing (Frequency down-converter, analog and digital filters, instrumental delay), the interdependencies between sub-systems can make this task even harder. A method based on the information provided by the TelCal¹ sub-system (in specific the Delay Measurements) will be used to help identify either the faulty unit or the wrong configuration which is causing the loss of coherence issue. This method uses granularity information to help find the cause of the problem.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years