05796827 is referenced by 247 patents and cites 7 patents.

An apparatus and method are disclosed for encoding and transferring data from a transmitter to a receiver, using the human body as a transmission medium. The transmitter includes an electric field generator, a data encoder which operates by modulating the electric field, and electrodes to couple the electric field through the human body. The receiver includes electrodes, in physical contact with, or close proximity to, a part of the human body, for detecting an electric field carried through the body, and a demodulator for extracting the data from the modulated electric field. An authenticator, connected to the receiver, processes the encoded data and validates the authenticity of the transmission. The apparatus and method are used to identify and authorize a possessor of the transmitter. The possessor then has secure access to, and can obtain delivery of, goods and services such as the distribution of money, phone privileges, building access, and commodities. Encryption provides rapid transmission and authentication of the transmitter, and a plurality of similar transmitters, with minimum vulnerability to counterfeit. Signal processing and digital communication components accommodate variations in location and orientation of the transmitter and receiver, and provide transmitters with long life times and high reliability.

Title
System and method for near-field human-body coupling for encrypted communication with identification cards
Application Number
8/749865
Publication Number
5796827
Application Date
November 14, 1996
Publication Date
August 18, 1998
Inventor
Thomas G Zimmerman
Cupertino
CA, US
Prabhakar Raghavan
Saratoga
CA, US
Don Coppersmith
Ossining
NY, US
Agent
Khanh Q Tran
Assignee
International Business Machines Corporation
NY, US
IPC
H04L 9/00
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