Semi-sequential transmission method and system using simultaneously several radio transmission frequencies for connecting a seismic reception assembly to a central control and recording laboratory
US4908803A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 21, 1989 |
| Grant date | Mar 13, 1990 |
| Priority date | — |
| Expiry date | Feb 21, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/223
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A semi-sequential transmission method and system are provided making it possible for successive groups of seismic acquisition apparatus to communicate simultaneously, using several transmission frequencies, with a central seismic laboratory. Each of said apparatus comprises a frequency synthesizer capable, by means of switches, of setting itself to any one of different frequencies, and means for automatic distribution of the frequencies between the apparatus of the same group. Each of the apparatus, being given an order number dependent on its position along a seismic profile to be studied, determines the difference between its own order number and an order number which it receives by radio and which is that assigned to the first acquisition apparatus of its group. Depending on the difference measured and respecting certain limitations, each acquisition apparatus attributes to itself its own transmission frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.