Radio interference reduction in interstellar communications: methods and observations

Abstract: The discovery of interstellar communication signals is complicated by the presence of radio interference. Consequently, interstellar communication signals are hypothesized to have properties that favor discovery in high levels of local planetary radio interference. A hypothesized type of interstellar signal, delta-t delta-f polarized pulse pairs, has properties that are similar to infrequent elements of random noise, while dissimilar from many types of known radio interference. Discovery of delta-t delta-f polarized pulse pairs is aided by the use of interference-filtered receiver systems that are designed to indicate anomalous presence of delta-t delta-f polarized pulse pairs, when pointing a radio telescope to celestial coordinates of a hypothetical transmitter. Observations reported in previous work (ref. arXiv:2105.03727) indicate an anomalous celestial pointing direction having coordinates 5.25 +- 0.15 hours Right Ascension and -7.6 +- 1 degrees Declination. Augmented interference reduction mechanisms used in the current work are described, together with reports of follow-up radio telescope beam transit measurements during 40 days. Conclusions and further work are proposed.