Electronic direction finder
Patent 5146231 Issued on September 8, 1992. Estimated Expiration Date: 
October 4, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 4, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesVHF Directional receiver Attitude sensing system Apparatus for and a method of determining compass headings Land vehicle navigation system Patent #: 4949268 InventorsAssigneeApplicationNo. 770850 filed on 10/04/1991US Classes:342/419, Portable342/357.08, Determining relative position (e.g., distance or direction)342/439Including combined effect indicatorExaminersPrimary: Blum, Theodore M.Attorney, Agent or FirmInternational ClassG01S 005/02AbstractAn electronic direction finder (10), having a housing (11) with a major axis (18), has a GPS receiver (28) and directional (31) and omnidirectional (30) antennas and provides an electrical signal (angle A) indicative of the direction of the housing axis (18) with respect to a predetermined compass heading (North). The electrical signal (angle A) is provided by using determined positions of the GPS receiver (28) and one GPS satellite to calculate a compass bearing from the receiver (28) to the one satellite and using the directional antenna (31) to determine the orientation of the housing axis (18) with respect to the satellite. This eliminates using electrical output terrestrial magnetism sensing devices to sense direction finder/receiver orientation with respect to compass direction, and therefore avoids the inaccuracies and costs associated with such magnetism sensing devices.Other References
| |
