04034160 is referenced by 12 patents and cites 4 patents.

A speech bandwidth compression system uses a first set of filters to separate the speech signal into baseband (300-800 hz) and highband (800-3200 hz) signals. The baseband (first formant or fundamental pitch frequency) is transmitted directly, and is also rectified to form harmonics which are mixed with the highband signals in a second set of (paired digital) filters which form sine and cosine forms (amplitude and phase information) of the harmonic components, which are then multiplexed for transmission to a receiver which provides the corresponding bandwidth expansion system to reconstruct the original speech signal.

Title
System for the transmission of speech signals
Application Number
5/664409
Publication Number
4034160
Application Date
March 5, 1976
Publication Date
July 5, 1977
Inventor
Petrus Josephus Van Gerwen
Eindhoven
NL
Agent
Henry I Steckler
Frank R Trifari
Assignee
U S Philips Corporation
NY, US
IPC
H04B 1/66
G10L 1/00
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