Radio frequency seismic gathering system employing an airborne blimp
US4236234A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1979 |
| Grant date | Nov 25, 1980 |
| Priority date | — |
| Expiry date | Jul 25, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/223
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The central station of a radio-connected seismic surveying system uses a tethered blimp carrying an antenna and an electronics package including a dc voltage/rf decoupler, a variable dc controlled preamplifier, a P-I-N diode switch for changing the antenna from receive to transmit operation, a transmitter and modulator and a battery. An rf coaxial cable to ground provides means for controlling the preamplifier gain and for switching the central station to the transmit mode by using appropriate dc signals. In the receive mode, the cable carries detected field unit seismic signals, which are detected by the blimp-carried antenna and preamplified by the blimp preamplifier, to the ground for suitable recording and further processing in the ground portion of the central station. An audio channel can also be modulated onto the transmit carrier of approximately 70 MHz to provide voice communications via the blimp electronics, if desired. Both the ground portion and the blimp portion of the central station are packaged for helicopter transporting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.