EP 1090371 A1 20010411 - DUAL MODE TRACKING SYSTEM
Title (en)
DUAL MODE TRACKING SYSTEM
Title (de)
DUALMODE NACHFÜHRSYSTEM
Title (fr)
SYSTEME DE REPERAGE BIMODE
Publication
Application
Priority
- US 9914325 W 19990624
- US 9055698 P 19980624
- US 24460099 A 19990204
- US 13016399 P 19990420
Abstract (en)
[origin: WO9967737A1] System for tracking mobile tags. Cell controllers with multiple antenna modules generate a carrier signal which is received by the tags. Tags shift the frequency of the carrier signal, modulate an identification code onto it, and transmit the resulting tag signal at randomized intervals. The antennas receive and process the response, and determine the presence of the tags by proximity and triangulation. The recursive-least squares (RLS) technique is used in filtering received signals. Distance of a tag from an antenna is calculated by measuring the round trip signal time. The cell controllers send data from the antenna to a host computer. The host computer collects the data and resolves them into positional estimates. Data are archived in a data warehouse, such as an SQL Server. Also disclosed is an article tracking system that supports both active and passive tags with a cell controller able to read both passive and active tag signals.
IPC 1-7
IPC 8 full level
G06K 7/00 (2006.01)
CPC (source: EP)
G06K 7/0008 (2013.01); G06K 7/10059 (2013.01); G06K 7/10356 (2013.01)
Citation (search report)
See references of WO 9967737A1
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
WO 9967737 A1 19991229; WO 9967737 A9 20000330; AU 4715999 A 20000110; EP 1090371 A1 20010411
DOCDB simple family (application)
US 9914325 W 19990624; AU 4715999 A 19990624; EP 99930669 A 19990624