Joined: 13 Feb 99
In radio astronomy, a "birdie" is an artificial signal added to the input data, for the purpose of verifying that the data processing system works correctly.
For example, in SETI@home we have periodically added a fixed-frequency sine wave to the analog radio telescope signal, then verified (by looking at spike signals computed by the client) that we're detecting it, and that the frequency is correct. This checks several parts of the system: signal digitization at the telescope, splitting, and most of the client logic.
This type of birdie, however, isn't useful for checking RFI removal, scoring, and the rest of Nebula. For that we need a much more sophisticated type of birdie: one that mimics an actual ET signal coming from a particular point in the sky. Such a signal would be detected only while the telescope is pointed close to that location.
It would be difficult to add such birdies into the raw time-domain data. Instead, we're planning to inject them at the start of the Nebula pipeline by adding signal records (spikes, Gaussians, etc.). Eric Korpela and I have begun working on this. For starters we're adding birdies that are always-on narrow-band signals. The basic idea is:
©2021 University of California
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.