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Description  |
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TECHNICAL FIELD
The present invention relates generally to enclosed electronic apparatus
and to housings that provide circuit connections.
BACKGROUND
As one example of an enclosed electronic apparatus, consider a system for
handling baggage in an airport terminal. Such a system incorporates radio
frequency identification (RFID) between interrogators and transceivers. In
such a system, each baggage tag is an enclosed, battery operated
transceiver.
In the field of radio frequency identification (RFID), communication
systems have been developed utilizing relatively large packages whose size
is on the order of that of a cigarette package or a substantial fraction
thereof, and generally speaking, have been fabricated using hybrid circuit
fabrication techniques. These relatively large electronic packages have
been affixed, for example, to railroad cars to reflect RF signals in order
to monitor the location and movement of such cars.
Other smaller passive RFID packages have been developed for applications in
the field of transportation, including the tracking of automobiles. These
packages include reflective systems of the type produced by Amtech Inc. of
Dallas, Tex. However, these reflective passive RFID packages which operate
by modulating the impedance of an antenna are inefficient in operation,
require large amounts of power to operate, and have a limited data
handling capability.
In still other applications of article location and tracking, such as in
the postal service or in the field of airline baggage handling and
transport, it has not been practical or feasible to use the above
relatively large and expensive RFID hybrid packages on smaller articles of
transport such as letters, boxed mail shipments or airline luggage.
Accordingly, in these latter areas of transport monitoring, as well as
many other areas such as inventory control of stored articles, article
location and tracking methods have traditionally employed bar code
identification and optical character recognition (OCR) techniques which
are well known in the art.
Bar code identification and OCR techniques are labor intensive and may, for
example, require several airline employees or postal workers to physically
manipulate the article and/or the bar code readers to read these bar codes
before the transported article reaches its final destination. In addition,
the cost of bar code readers and optical character readers is high,
limiting the number of locations at which these readers can be used.
Furthermore, both bar code readers and optical character readers tend to
be highly unreliable.
In yet further and somewhat unrelated fields of: (1) animal tracking and
(2) plant tracking, other types of passive RFID tags have been developed
by Hughes/IDI/Destron of Irvine, Calif. These tags utilize a coil wrapped
around a ferrite core. Such passive RFID tags have a very limited range,
on the order of nine (9) inches, have a very limited data handling
capability, and are not field programmable. In addition, these tags are
limited in data storage capacity and are slow in operation.
In view of the problems described above and related problems that
consequently become apparent to those skilled in the applicable arts, the
need remains for enclosed electronic apparatus including transceivers
wherein the enclosure is inexpensive, readily manufactured in high volume,
appropriate in size for use as a stamp, label, or tag, and, in the case of
transceivers, operable over distances of several hundred feet without
regard for the spacial orientation of the enclosure.
SUMMARY
The general purpose and principal object of the present invention is to
provide a novel alternative approach to all of the above prior art RFID,
OCR, and bar code type location tracking and data storage systems. This
new approach as described and claimed herein represents a fundamental
breakthrough in the field of article transport control in a wide variety
of fields, of which the fields of airline baggage transport, delivery of
parcels and mail, and inventory control are only three examples.
To accomplish this purpose and object, we have invented and developed a new
and improved radio frequency identification device, an associated
electrical system, and a method for communicating with a remote RFID
device from a local interrogator and controller. The size of this new
device will typically be on the order of one inch square and 0.03 inches
thick, or only slightly larger and slightly thicker than a postage stamp.
This device includes, in combination, an integrated circuit (IC) which is
mounted in an approximately one inch square package and is encapsulated,
for example laminated, in a flexible or rigid thin film material. This
material may also include a suitable adhesive backing for reliably
securing the package to an outer surface or printed label of an article of
interest. The IC includes therein a receiver section for driving suitable
control logic and memory for decoding and storing input information such
as an identification number, the baggage owner's name, point of origin,
weight, size, route, destination, and the like. This memory includes, but
is not limited to, PROMs, EPROMs, EEPROMs, SRAMs, DRAMs, and ferroelectric
memory devices. The IC also includes a transmitter section therein
operative for transmitting this information to an interrogator upon
subsequent IC interrogation. An RF antenna is placed in a desired
geometrical configuration (for example, monopole, dipole, loop, bow-tie,
or dual-dipole) and incorporated within or on the thin film material and
adjacent to the IC in an essentially two dimensional structure, neglecting
the approximately 30 mil thickness dimension of the completed structure.
Advantageously, a thin battery is connected to the IC for providing power
to the IC. The IC also incorporates circuitry to allow for operation in a
sleep mode during transit and in storage in order to conserve power. Thus,
at shipment points of origin, destination, and locations in transit, an
operator may encode data into the IC or interrogate the IC by signaling
the IC from a remote location to thereby "wake up" the IC without engaging
in any hands-on operation.
In a preferred embodiment of the invention, the integrated circuit receiver
and transmitter are operated in a spread spectrum mode and in the
frequency range of 200 Mhz to 10 GHz, with the range of 800 MHz to 8 GHz
being the range of most importance. This operation has the effect of
avoiding errors or improper operation due to extraneous signal sources and
other sources of interference, multipathing, and reflected radiation from
the surrounding environment.
Accordingly, it is a further object of this invention to provide an RFID
electronic device of the type described and method of fabricating such
device.
Another object of this invention is to provide an RFID system and method of
operation of the type described which utilizes RF transmitting and
receiving sections on a single IC. Such a system has applications for
tracking people or articles in both storage and transit.
Another object of this invention is to provide an electronic device of the
type described which does not include bulky hybrid circuits, use
modulation techniques described above for passive RFID tags, nor require
scanning of bar codes, bar code readers, optical character readers, or
especially clean operating environments.
Another object of this invention is to provide an electronic device of the
type described which may be manufactured using integrated circuit
fabrication and packaging processes.
Another object of this invention is to provide an electronic device of the
type described which may be reliably and economically manufactured at high
yields and at a high performance to price figure of merit.
Another object of this invention is to provide an RFID device of the type
described which is field writable and has a transmission range greater
than five (5) feet.
Another object of this invention is to provide a novel assembly process for
manufacturing the RFID electronic device described herein.
Another object is to provide a manufacturing process of the type described
which is conducive to high speed automation.
Another object is to provide an enclosed electronic device of the type
described which is further conducive to high speed product usage, since
these RFID devices may be supplied to the customer in a tape and reel
format, a fan fold format, or a sheet format.
Another object of this invention is to provide an RFID device of the type
described which may be powered with the use of an RF coil and capacitor
and without the use of a battery. Such device is also referred to herein
as the "passive" device embodiment. However, the term "passive" refers
only to the fact that no battery is used, whereas the electrical circuitry
on the IC is indeed active while being powered by the RF coil and
capacitor combination.
Another object of this invention is to provide a non-contact method of
object and person detection and location which can serve as a replacement
for metal-to-metal contact in smart card applications and as a replacement
for magnetic strip, bar code, and other types of contact-powered
electronics. This novel method of object detection and location represents
a significant saving of time and manual effort. For example, consider the
time and effort involved when a person must first remove a smart card from
a pocket or billfold and then insert the card in a card reader device
before being allowed entry into a secured area within a building.
Another object of this invention is to provide an electronic device,
system, and communication method of the type described which represents,
in novel combination, a fundamental breakthrough in many diverse fields of
article shipment, including the parcel post and postal fields, the airline
industry, inventory control for many manufacturing industries, security,
waste management, personnel, and the like.
Accordingly, an enclosed electrical assembly of the present invention
includes: a rigid or flexible thin film support member having an
integrated circuit (IC) disposed thereon and an antenna incorporated
within the IC or positioned adjacent to the IC within a predetermined area
of the thin support member; means on the IC for receiving and encoding
data relating to the article being stored or shipped; and means on the IC
for reading the stored data and transmitting this data to an operator at a
remote location.
According to a first aspect of such an assembly, a base member and a cover
member each having conductive patterns developed thereon connect the IC in
series with two thin film batteries. By arranging two batteries with the
IC, no substantial current flows through a laminated or folded portion of
the assembly. Smaller signal levels, lower power operation, and longer
useful life of the assembly results.
According to another aspect, antenna coupling is also provided to the IC
without current flow through a laminated or folded portion of the
assembly. Greater sensitivity in receiving and lower losses in
transmitting result.
According to another aspect of the present invention, an RFID device has
two modes of operation are provided with a wake-up circuit. The wake-up
circuit senses in-band energy and switches from a sleep mode to an
operating (waked) mode. The sleep mode being useful during transit and
storage of the RFID device to conserve battery power.
According to another aspect of such an RFID device, the IC includes
receiver and transmitter sections characterized by spread spectrum
modulation. Use of spread spectrum modulation reduces data transmission
and reception errors, reduces the possibility of improper operation in
response to extraneous signal sources, reflected radiation from a
surrounding noisy environment, and other interference. Battery power is
thereby conserved.
According to another aspect of the present invention, the enclosure
includes an adhesive on an outer surface thereof. The adhesive permits
reliable and convenient securing of a device of the present invention to
an article being transported or stored.
According to yet another aspect of the present invention, by enclosing a
transceiver in film, an extremely light weight, durable, and thin package
results. Such a package is appropriate for use in replacement of or in
conjunction with the conventional handwritten label, conventional
hand-cancelled or postage-metered stamp, and the conventional baggage tag.
According to another aspect of the present invention, the frequencies of
radio communication, modulation scheme, geometry of the antenna, capacity
of the battery, and electrical properties of the enclosure cooperate for
omnidirectional communication between an enclosed transceiver of the
present invention and a distant interrogator. No manual manipulation of
the interrogator or transceiver is required for area-wide communication
such as confirming the contents of a delivery vehicle or verifying
inventory in place, to name a few examples.
According to an aspect of another embodiment of the present invention, a
plurality of transceivers are enclosed and laminated between a pair of
films. One side of one of the films has adhesive capability. The
transceivers are separated and arranged on a backing. A roll or tape of
the backing having transceivers removably attached thereto is enclosed in
an RF tight dispenser. The dispenser provides convenient access to
unprogrammed transceivers for use on articles to be shipped. When removed
from the dispenser, a transceiver communicates with an interrogator in the
area for establishing transceiver identity, shipping authorization,
destination or storage criteria, date of issue, and similar information.
By shielding transceivers within the dispenser from wake-up signals,
battery power is conserved.
These and other embodiments, aspects, advantages, and features of the
present invention will be set forth in part in the description which
follows, and in part will become apparent to those skilled in the art by
reference to the following description of the invention and referenced
drawings or by practice of the invention. The aspects, advantages, and
features of the invention are realized and attained by means of the
instrumentalities, procedures, and combinations particularly pointed out
in the appended claims.
DESCRIPTION OF THE DRAWINGS
FIG. 1A and FIG. 1B are functional block diagrams of enclosed transceivers
of the present invention.
FIG. 2 is a perspective view of an enclosed transceiver as shown in FIG.
1A.
FIG. 3 is a plan view showing the conductive patterns on the base and cover
members used in FIG. 2, including dotted line outlines of the locations
for the IC and batteries.
FIG. 4A through FIG. 4D are cross sectional views taken along lines 4--4 of
FIG. 3 showing four processing steps used in constructing the enclosed
transceiver shown in FIG. 3.
FIG. 5A is a perspective view of an alternate embodiment of the invention
wherein the IC is mounted on a parallel plate capacitor which in turn is
mounted on a battery.
FIG. 5B is an enlarged portion of FIG. 5A.
FIG. 6A through FIG. 6E are cross sectional views taken along lines 6--6 of
FIG. 5 showing five processing steps used in constructing the embodiment
shown in FIG. 5.
FIG. 7 is a cross-sectional view showing an arrangement of battery and
capacitor alternate to the embodiment shown in FIG. 5.
FIG. 8 is a perspective view of another alternate | | |
