Passive ranging system utilizing range tone signals
US5173690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1991 |
| Grant date | Dec 22, 1992 |
| Priority date | — |
| Expiry date | Jul 11, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S11/026
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A passive ranging system for determining the slant range from a ground station to a drifting radiosonde. In one embodiment, the ground station receives meteorological data ranging and internal temperature signals from the radiosonde. The data signals are read out as ambient conditions of the atmosphere and the range signal is phase-compared to a reference signal at periodic intervals. Changes in frequency due to temperature fluctuations in the radiosonde components are factored into the phase-comparison, and the resultant change in phase represents movement of the radiosonde. In another embodiment the range tone from a remote broadcast station is retransmitted by the radiosonde and received at the ground station simultaneously with the same tone directly from the broadcast station. The phase lag is measured and coupled with measurements of direction from the ground station to the radiosonde, and with the distance between the ground station and the broadcast station for determining the slant range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.