Browse Prior Art Database

# RF Based User Authentication

IP.com Disclosure Number: IPCOM000245643D
Publication Date: 2016-Mar-23
Document File: 4 page(s) / 373K

## Publishing Venue

The IP.com Prior Art Database

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 55% of the total text.

Page 01 of 4

RF Based User Authentication

3. Passwords can be tiringly complex (capital, lower case, number, symbol)

Solution Summary:

Capitalize on the unique geometry of a person's hand as detected by its perturbation of a 3D RF sphere. The sphere is created by 3 or more RF oscillators susceptible to detuning.

RF sphere generation and measurement

Two RF oscillators GS, and GREF are running at the same frequency (0.2MHZ-20MHZ, for example). GS also has receiver antenna which is mounted on one corner of the device. A conductive body such as a hand approaching the antenna will cause the output frequency of GS to diverges from G REF.

GS, and GREF outputs are mixed to yield sum and difference terms, of which the high frequency additive term is filtered to leave only the differential measurement. This preconditioned analog signal is digitized and fed to a DSP. The DSP input signal is defined by Equation 1.

A sin(ωSt) + A sin(ωREFt) = 2A sin((ωSREF)t/2) cos ((ωS REF)t/2)

= 2A cos (Δωt/2) sin(ωt), where Δω = (ωS REF)/2 and ωS ≈ ωREF ≈ ω

= 2A cos (Δωt/2), after low pass filtering. Equation 1.

 One measurement oscillator GS1 provides proximity measurement, R in polar coordinates.
 Two measurement oscillators GS1 and GS2 provide measurement which can also translate to a position along a line on a 2D display.

 The preferred embodiment, Three measurement oscillators GS1 ,GS2 and GS3 provide measurement which can also translate to a position within an area on a 3D Space.

Problem:

Page 02 of 4

Figure 2. illustrates the preferred embodiment with a minimum of at least...