U.S. patent number D574,369 [Application Number D/303,658] was granted by the patent office on 2008-08-05 for broken-loop rfid reader antenna for near field and far field uhf rfid tags.
This patent grant is currently assigned to Impinj, Inc.. Invention is credited to Ronald A. Oliver.
United States Patent |
D574,369 |
Oliver |
August 5, 2008 |
Broken-loop RFID reader antenna for near field and far field UHF
RFID tags
Claims
CLAIM The ornamental design for a broken-loop RFID reader antenna
for near field and far field UHF RFID tags, as shown.
Inventors: |
Oliver; Ronald A. (Seattle,
WA) |
Assignee: |
Impinj, Inc. (Seattle,
WA)
|
Appl.
No.: |
D/303,658 |
Filed: |
February 14, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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29265163 |
Aug 25, 2006 |
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Current U.S.
Class: |
D14/230;
D14/233 |
Current International
Class: |
1403 |
Field of
Search: |
;D14/138,230-238,299,358
;D12/42,43
;343/700MS,700R-705,711-713,741,748,767,795,819,840,846,866,871-908
;455/90.2,90.3,91,128,269,344,347,562.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Zarfas; Louis S
Assistant Examiner: Windmuller; John
Attorney, Agent or Firm: Adorno & Yoss, LLC Turk; Carl
K. Kavounas; Gregory T.
Description
An article in which the design is embodied is an antenna for a
Radio Frequency Identification (RFID) reader system, as it would be
used for reading Ultra High Frequency (UHF) RFID tags.
The design includes one or more conductive loops, at least one of
which is broken into segments. The segments can be electrically
driven at feedpoints by an electrical signal alternating at the
proper frequency, which can be around 900 MHz.
In the far field, an electromagnetic pattern is formed that is
equivalent to, and sometimes indistinguishable from, that of a
dipole. This way RFID tags can be read as known.
In the near field, each segment generates an individual magnetic
field. Plus, the segments are so arranged that the individual
magnetic fields are cumulated, to form an aggregate magnetic field
that can be used for reading the UHF RFID tags. The magnetic field
can read RFID tags better than an electromagnetic field, in some
instances that involve fluids or metals with which the RFID tags
can be associated.
Advantageously, the segments of the broken loop(s) are further
arranged so that not all of them need be electrically driven. Only
some need be driven; and the driving field couples also into the
others. By proper geometry, dimensioning, and the like, the phase
difference of each field propagating within a segment can be
substantially matched to that of coupling to another segment, so
that the generated individual magnetic fields are cumulated.
The FIGURE is a top plan view of a broken-loop RFID reader antenna
for near field and far field UHF RFID tags showing my new design.
It is understood that the broken line segments in the drawing form
no part of the claimed design.
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