A seismic measuring system including gps receivers

2004.07.15, US, 10 / 891,800 (41) Alm.tilgj 2006.03.15 (71) Seeking (72) Inventor (74) Proxy

NovAtel Inc, 1120-68th Avenue North East, ABT2E8S5 CALGARY, CA Patrick C Fenton, 304 Sandringham Court, ABT3K3V6 CALGARY, CA Tandberg Patent Office AS, PO Box 7085 Majorstua, 0306 OSLO, NO (54) Name Seismic Measurement System with GPS Receivers (57 ) Summary

System (100) for analysis of three-dimensional seismic data, with multiple digitizers (7) and each with a configuration of geophones (8), a central (12) for data recording and control, a GPS base receiver (3) with associated antenna (5 ) and with substantially unobstructed view to the sky, and low power GPS slave receivers (6) near the respective units (7) and arranged to retrieve GPS satellite signals (9) using tracking assist information from the base receiver (3). Thereby, they can receive GPS satellite signals which are relatively weak, for example due to trees (11) which block the view. The information from the slave receivers (6) extends over a period of time which allows them to accurately position them. even if they can only retrieve data through satellites over only three or four relatively short time intervals at different sky positions. The slave receivers generate local time signals for the units (7), based on the GPS codes and synchronization in the system (100). If a given slave receiver (6) cannot follow any satellite signal for a particular period, a nearby such receiver (6) may transmit the time information needed for the collection of geophone data.

<img file="NO20060752A_D0001.tif" />