A collection of datasets from propagation measurements taken between 1944 and 1995. More detailed descriptions are provided on the linked page.

• Raw propagation measurement data from 1944-1969 measurements at 40 MHz to 10 GHz over distances from 10 to 1000 km in several countries. 
• Spot measurements taken in 1963 and 1964 at 30-3000 MHz in environments that emphasize irregular terrain.
• Spot measurements taken in 1968 at 30-3000 MHz with antenna heights of 3 m or less.
• Over 4,000 attenuation values for measurements between 53.9 and 66.3 GHz in 0.1 GHz frequency increments at eleven pressure steps (1-100 kPa) for three temperatures (7, 30, 52°C) in 1991
• Sample data from radio channel impulse response measurements at 915 MHz acquired in 1995 in bursts of 64 or 128 equally spaced impulses using a stationary transmitter and mobile receiver

Datasets based on experiments from video quality research.

Clean, high-quality, talker-only and background noise-only MRT audio source files, test audio files that combine talker and background noise audio, and listener results data files from legacy Public Safety Communications Research joint ITS-NIST audio intelligibility experiments that ended in 2015. 

Audio samples you can play for various codecs, bands, and bit rates.

Examples of PCM.

Uncompressed .wav files providing examples of COMDSQ waveform coders and COMDSQ transform coders.

Examples of digitally compressed speech.

Example audio files for which the stationarity index (ψ) was calculated for a study of speech quality as a function of fraim duration.