C. Donnelly

The SERENDIP piggyback SETI project

The SERENDIP project is an ongoing program of monitoring and processing broadband radio signals acquired by existing radio astronomy observatories. SERENDIP operates in a piggyback mode: it makes use of whatever observing plan (sequence of frequencies, sky coordinates, and polarizations) is under way at its host observatory. Moreover, the SERENDIP data acquisition system, once installed, operates autonomously. This approach makes it possible to obtain large amounts of high quality observing time in a manner that is economical and that does not adversely affect ongoing radio astronomy survey work. The SERENDIP II system has been installed at the NRAO 300-foot telescope at Green Bank, West Virginia, and has operated there for several thousand hours. In this report, we summarize our findings from these observations and describe the present status of the project. Two key elements of SERENDIP are the automated data acquisition system that uses adaptive thresholds and logs only statistically significant peaks in the real-time power spectra, and the subsequent off-line analysis programs that identify and reject a variety of interference signals. Several specific correlations have been identified that offer promise. At present, the development and testing of these interference rejection algorithms is the main thrust of our work.

SERENDIP SETI project: new instrumentation for SETI and results of the recent Arecibo sky survey

The SERENDIP SETI group is currently conducting search operations on the worlds largest radio telescope at the Arecibo Observatory in Puerto Rico. The third generation SERENDIP system, SERENDIP III, is a 4 million channel Fast Fourier Transform-based spectrum analyzer with 0.6 Hz frequency resolution. In this talk we will discuss results of our recent 3.5 year sky survey. SERENDIP has looked at 95 percent of the sky visible from Arecibo in the range from 424 to 436 MHz, analyzed 1.5 X 1014 spectral bins, and logged information on over 300 million signals. The fourth generation SERENDIP system expands on the SERENDIP III design. SERENDIP IV computes 200 billion operations each second providing spectral analysis on 168 million channels every 1.7 seconds. We will also discuss the design and use of the SERENDIP IV system and future observing plans.