Browse Prior Art Database

IMPLICIT GPS POSITIONING CALCULATION FOR MOBILE MESSAGING DEVICES

IP.com Disclosure Number: IPCOM000004741D
Original Publication Date: 2001-Apr-25
Included in the Prior Art Database: 2001-Apr-25
Document File: 1 page(s) / 6K

Publishing Venue

Motorola

Related People

S. Andrew Hopper: AUTHOR

Abstract

IMPLICIT GPS POSITIONING CALCULATION FOR MOBILE MESSAGING DEVICES

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IMPLICIT GPS POSITIONING CALCULATION FOR MOBILE MESSAGING DEVICES

by S. Andrew Hopper

Mobile cellular subscribers are increasingly reliant upon messaging as a medium of communication to both stationary individuals as well as mobile users.

Unfortunately, current textual messaging schemes can prove problematic for the exchange of positional descriptions.

Because of the high latency inherent in textual messaging services (primarily because of slow "numeric keypad typists"), this particular medium is typically not conducive to an interactive conversation.

Even less hostile interfaces, however, do not facilitate the transfer of positional data: mobile visitors unfamiliar with a geographic area either are not capable of accurately describing their position to the receiver of the message, or can forget to include relevant positional information within the communiqué.

Furthermore, the inclusion of a lengthy textual description of positional data within every message would be problematic in terms of bandwidth and wireless infrastructure capacity. For these reasons, relating relative positional information between users can be cumbersome at best.

To accommodate this deficiency, messaging devices that are equipped with Global Position Service (GPS) receivers could include positioning information to the "headers" of all messages and the calculation of the relative position of two mobile subscribers could be effected implicitly.

By comparing the GPS position of the reader of a message with that of the sender of the message, the relative offset could then be made available to the reader through a query or configurable interface scheme.

This implicit inclusion of GPS positional information within all messages would alleviate the aforementioned difficulties since such positional information does not impact the sender (in terms of responsibility) and is succinct enough to have a minimal impact upon the capacity of the cellular network.

Highly accurate positional data can be captured in 18 bytes (9 digits per parallel/meridian), which can easily be compressed to 1 digit per nibble and thus transferred in a 9 byte format (note that further compression of this data is certainly possible).

By utilizing this technique, users can determine exact relative offset to other stations. For instance, upon a newly received message Mobile Subscriber (MS) A may now be aware that he is only 1/2 mile south of MS B.

Additionally, this technique allows users to make informed decisions regarding future action: if MS A and MS B are planning on a rendezvous for lunch and MS A is 10 miles from MS B and traveling toward him at 40 MPH, B may elect to wait before leaving for the restaurant that is 2 miles away. Finally, advanced wireless devices could actually determine the exact location of users upon highways or relative to landmarks by correlating the positional data with stored maps.