About: http://webisa.webdatacommons.org/231346979

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	Beat frequencies generated by the mixer can only be 0, 2, 4, 6, 8...KHZ. Thus, if the Doppler filter 28 removes all frequencies including 2 KHZ and above, the unwanted beat frequencies are eliminated.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com