About: http://webisa.webdatacommons.org/404223396

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Signal distortion and attenuation, due to e.g. reflections, is less critical than in a signal using just one- (e.g. Phase shift keying) or two frequencies to modulate/encode the data.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com