- 专利标题: Location system adapted for use in multipath environments
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申请号: US252842申请日: 1994-06-02
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公开(公告)号: USRE36791E公开(公告)日: 2000-07-25
- 发明人: Alan C. Heller
- 申请人: Alan C. Heller
- 申请人地址: TX Dallas
- 专利权人: Precision Tracking FM, Inc.
- 当前专利权人: Precision Tracking FM, Inc.
- 当前专利权人地址: TX Dallas
- 主分类号: G01S5/06
- IPC分类号: G01S5/06 ; G06K7/00 ; G07C9/00 ; G01S3/02 ; H04L27/30
摘要:
A radiolocation system for multipath environments, such as for tracking objects in a semiconductor fabrication facility (FIGS. 1a-1b), includes an array of receivers (20) distributed within the tracking area, coupled to a system processor (40) over a LAN. A TAG transmitter (30) located with each object transmits, at selected intervals, spread spectrum TAG transmissions including at least a unique TAG ID. In a high resolution embodiment, object location is accomplished by time-of-arrival (TOA) differentiation, with each receiver (FIG. 2b) including a TOA trigger circuit (64) for triggering on arrival of a TAG transmission, and a time base latching circuit (65) for latching the TOA count from an 800 MHz time base counter. In a low resolution embodiment, each receiver of the array is assigned a specific location-area, and receives TAG transmissions almost exclusively from TAGs located in that area, thereby eliminating the need for any time-of-arrival circuitry.
公开/授权文献
- US4891719A Fast closure method for a data signal channel 公开/授权日:1990-01-02
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