Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6754502 | Geolocation of cellular phone using supervisory audio tone transmitted from single base station | Robert C. Hildebrand, Julian Bartow Willingham, Robert W. Boyd | 2004-06-22 |
| 6292665 | Geolocation of cellular phone using supervisory audio tone transmitted from single base station | Robert C. Hildebrand, Julian Bartow Willingham, Robert W. Boyd | 2001-09-18 |