3623160 is referenced by 93 patents and cites 4 patents.

Multitone data-transmitting apparatus employing sinusoidal synthesis with harmonic cancellation. A multitone data transmitter employs relative phase displacements between plural digital waveforms all of which are representative of a tone to be transmitted and a weighted summing network for summing the plural waveforms so as to cancel undesirable harmonics of the frequency tone to be transmitted. In the illustrated FSK modulator, four square waves having relative phase shifts of .pi./4 radians are given suitable summing weights so as to cancel the third and fifth harmonic of any selected one of the FSK tones.

Title
Data modulator employing sinusoidal synthesis
Application Number
04/858,721
Publication Number
3623160
Application Date
September 17, 1969
Publication Date
November 23, 1971
Inventor
MacDavid Kenneth R
Shuda Donald G
Giles George R
Assignee
Sanders Associates
IPC
H03k 13/02
H04L 25/49
H04L 27/26
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