Communications: directive radio wave systems and devices (e.g. – Directive – Position indicating
Reexamination Certificate
2005-01-04
2005-01-04
Issing, Gregory C. (Department: 3662)
Communications: directive radio wave systems and devices (e.g.,
Directive
Position indicating
Reexamination Certificate
active
06839027
ABSTRACT:
A process for measuring the location of people and objects carrying radio frequency (RF) transmitters (TXs) that transmit messages to a plurality of RF receivers (RXs) located in a space. Each RX is in communication with a computer of a computer network and forwards data received from the TXs to the network via its associated computer, along with a value indicating the signal strength of the received TX transmission. The signal strengths attributable to the same transmission are used to form a locating signal strength vector which is then compared to exemplary vectors generated from signal strength readings gathered in a calibration procedure from a set of representative locations in the space. In comparing the locating vector to the exemplary vectors, constraints are enforced on movements between locations (e.g., cannot pass through walls) and to probabilistically enforce expectations on transitions between locations.
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Krumm John
Smith Gregory
Issing Gregory C.
Lyon Richard T.
Lyon & Harr LLP
Microsoft Corporation
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