English
Related papers

Related papers: Symbol repetition in interstellar communications: …

200 papers

Interstellar communication transmitters, intended to be discovered and decoded to information bits, are expected to transmit signals that contain message symbols quantized in at least one of the degrees of freedom of the transmitted signal.…

Signal Processing · Electrical Eng. & Systems 2022-03-21 William J. Crilly

Interstellar communication signals have been conjectured to be present, albeit difficult to identify. Experiments conducted since 2018 indicate an anomalous presence of a type of speculated interstellar signal, delta-t delta-f polarized…

Signal Processing · Electrical Eng. & Systems 2024-07-02 William J. Crilly

Extraterrestrial communication signals are hypothesized to be present in an extensive search space. Using principles of communication theory and system design, methods are studied and implemented to reduce the signal search space, while…

Signal Processing · Electrical Eng. & Systems 2024-04-16 William J. Crilly

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…

Signal Processing · Electrical Eng. & Systems 2021-06-21 William J. Crilly

Prior work using synchronized, geographically spaced radio telescopes, and a radio interferometer, suggests that narrow-bandwidth polarized pulse pair measurements repeatedly falsify a noise-cause hypothesis, given a prior celestial…

Signal Processing · Electrical Eng. & Systems 2024-12-10 William J. Crilly

In prior work, conducted since 2017, two celestial pointing directions have been observed to be associated with the measurement of anomalous high counts of narrow bandwidth, short duration, polarized radio frequency pulse pairs. The prior…

Signal Processing · Electrical Eng. & Systems 2025-04-29 William J. Crilly

Experiments conducted since 2018, using three geographically spaced synchronized radio telescopes, and a radio interferometer, indicate the presence of anomalous narrow bandwidth pulse pairs, conjectured to be sourced from a celestial…

Signal Processing · Electrical Eng. & Systems 2024-11-05 William J. Crilly

A system of synchronized radio telescopes is utilized to search for hypothetical wide bandwidth interstellar communication signals. Transmitted signals are hypothesized to have characteristics that enable high channel capacity and minimally…

Signal Processing · Electrical Eng. & Systems 2022-03-01 William J. Crilly

Pulsar radio emission undergoes dispersion due to the presence of free electrons in the interstellar medium (ISM). The dispersive delay in the arrival time of pulsar signal changes over time due to the varying ISM electron column density…

A search for pulse signals was carried out in a new sky area included in the monitoring program for the search for pulsars and transients. Processing of several months data recorded in six frequency channels with a total bandwidth of 2.5…

High Energy Astrophysical Phenomena · Physics 2022-07-20 V. A. Samodurov , S. A. Tyul'bashev , M. O. Toropov , S. V. Logvinenko

Signals from radio pulsars show a wavelength-dependent delay due to dispersion in the interstellar plasma. At a typical observing wavelength, this delay can vary by tens of microseconds on five-year time scales, far in excess of signals of…

Pulsars with periods more than 0.4 seconds in the declination range -9o < decj < 42o and in the right ascension range 0h < r.a.< 24h were searched in parallel with the program of interplanetary scintillations monitoring of a large number of…

We consider interstellar scintillations as a cause of intermittency in radio signals from extraterrestrial intelligence (ETI). We demonstrate that scintillations are very likely to allow initial detections of narrowband signals from distant…

Astrophysics · Physics 2009-10-30 James M. Cordes , T. Joseph W. Lazio , Carl Sagan

Dispersion in the interstellar medium is a well known phenomenon that follows a simple relationship, which has been used to predict the time delay of dispersed radio pulses since the late 1960s. We performed wide-band simultaneous…

Synchronized radio telescope-based experiments conducted since 2017, together with subsequent interferometer experiments, provide evidence of an anomalous source of 3.7 Hz bandwidth pulses, sourced from near the direction of the star Rigel.…

Signal Processing · Electrical Eng. & Systems 2026-04-16 William J. Crilly

Diffuse radio recombination lines (RRLs) in the Galaxy are possible foregrounds for redshifted 21~cm experiments. We use EDGES drift scans centered at $-26.7^o$~declination to characterize diffuse RRLs across the southern sky. We find RRLs…

The cosmological reionization can be studied in the radio through the tomographic view offered by the redshifted 21-cm line and the integrated information carried out by the diffuse free-free emission, coupled to the Comptonization…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 T. Trombetti , C. Burigana

We have made observations of 98 low-Galactic-latitude pulsars to measure pulse broadening caused by multipath propagation through the interstellar medium. Data were collected with the 305-m Arecibo telescope at four radio frequencies…

We are performing a transient, microsecond timescale radio sky survey, called "Astropulse," using the Arecibo telescope. Astropulse searches for brief (0.4 {\mu}s to 204.8 {\mu}s), wideband (relative to its 2.5 MHz bandwidth) radio pulses…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 J. Von Korff , P. Demorest , E. Heien , E. Korpela , D. Werthimer , J. Cobb , M. Lebofsky , D. Anderson , B. Bankay , A. Siemion

Results of experimental investigations of a new assumed interaction in nature with the aid of high-current magnets, torsion and piezoresonance balances, high-precision gravimeter, fluctuations in intensity of betta-decay of radioactive…

General Physics · Physics 2008-08-21 Yu A. Baurov
‹ Prev 1 2 3 10 Next ›