David W Vaness from Chandler, AZ, age 71

Delta-Sigma Signal Density Modulation For Optical Transducer Control
view source
US Patent:

7915838, Mar 29, 2011
Filed:

Jun 29, 2007
Appl. No.:

11/823904
Inventors:

David VanEss - Arlington WA, US
Assignee:

Cypress Semiconductor Corporation - San Jose CA
International Classification:

H05B 37/02
H03M 3/00
US Classification:

315302, 341143
Abstract:

A controller for optical transducers uses delta-sigma signal density modulation to reduce electromagnetic interference.

Decoding Of Signals Using Cophase And Differentiating Signal Detection
view source
US Patent:

50070690, Apr 9, 1991
Filed:

Nov 13, 1987
Appl. No.:

7/120594
Inventors:

David W. VanEss - Arlington WA
Assignee:

Talkie Tooter Inc. - Sedro Woolley WA
International Classification:

H04L 2714
H04L 2716
US Classification:

375 80
Abstract:

The disclosed decoder (14) produces an output signal when a receiver (12) signal contains frequencies that are sequentially within a predetermined passband surrounding detection frequencies f. sub. 1 and f. sub. 2. The receiver signal is mixed at exclusive-OR logic gates (52, 54) with cophase reference signals R1 and R2, which are produced by a reference tone generator (18) and have a frequency f. sub. r that corresponds to the desired tone detection frequency f. sub. 1 and f. sub. 2 and a phase difference of 90. degree. The outputs of gates (52, 54) are applied to low pass filters (56, 58), which produce outputs having a frequency. DELTA. f equal to the absolute value of the difference between the input and reference frequencies f. sub. i and f. sub. r, provided that. DELTA. f is below the filter's cutoff frequency f. sub. c1.