CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit under 35 U.S.C. § 119 of U.S. Provisional Application No. 60/070,444, filed Jan. 5, 1998 and U.S. Provisional Application Serial No. 60/103,304, filed Oct. 6, 1998. Said U.S. Provisional Application No. 60/070,444 and U.S. Provisional Application Serial No. 60/103,304 are herein incorporated by reference in their entirety.

INCORPORATION BY REFERENCE

The following U.S. Patents and Patent Applications are hereby incorporated herein by reference in their entirety:

U.S. Pat. Nos.

U.S. Pat. No.

Issue Date

Filing Date

Attorney Docket No.

5,521,601

05/28/96

04/21/95

YO995-0088

5,528,222

06/18/96

09/09/94

YO994-180

5,538,803

07/23/96

11/23/94

YO994-0073

5,550,547

08/27/96

09/12/94

YO994-185

5,552,778

09/03/96

11/23/94

YO994-0232

5,554,974

09/10/96

11/23/94

YO994-0071

5,563,583

10/08/96

11/23/94

YO994-070

5,565,847

10/15/96

11/23/94

YO994-0072

5,606,323

02/25/97

08/31/95

YO995-157

5,635,693

06/03/97

02/02/95

YO994-0215

5,673,037

09/30/97

09/09/94

YO994-184

5,680,106

10/21/97

10/27/95

YO995-0219

5,682,143

10/28/97

09/09/94

YO994-170

5,729,201

03/17/98

06/29/95

YO995-109

5,729,697

03/17/98

04/24/95

YO995-076

5,736,929

04/07/98

06/07/96

YO996-085

5,777,561

07/07/98

09/30/96

YO996-178

U.S. Nonprovisional patent applications Ser. Nos.

Application Ser. No.

Filing Date

Attorney Docket No.

08/681,741

07/29/96

YO996-037

08/660,249

06/07/96

YO996-084

(allowed 4-28-98)

08/621,784

03/25/96

YO996-031

08/626,820

04/03/96

YO995-158

08/646,539

05/08/96

YO996-068

08/681,741

07/29/96

YO996-037

08/694,606

08/09/96

YO995-218

08/790,639

01/29/97

YO997-024

08/790,640

01/29/97

YO997-023

08/733,684

10/17/96

YO996-195

08/862,149

05/23/97

YO997-116

08/862,912

05/23/97

YO997-115

08/862,913

05/23/97

YO997-114

08/909,719

08/12/97

YO995-109B

(allowed)

08/935,989

10/23/97

YO997-310

U.S. Nonprovisional patent applications Ser. Nos.

Application Ser. No.

Filing Date

Attorney Docket No.

08/681,741

07/29/96

YO996-037

08/660,249

06/07/96

YO996-084

(allowed 4-28-98)

08/621,784

03/25/96

YO996-031

08/626,820

04/03/96

YO995-158

08/646,539

05/08/96

YO996-068

08/681,741

07/29/96

YO996-037

08/694,606

08/09/96

YO995-218

08/790,639

01/29/97

YO997-024

08/790,640

01/29/97

YO997-023

08/733,684

10/17/96

YO996-195

08/862,149

05/23/97

YO997-116

08/862,912

05/23/97

YO997-115

08/862,913

05/23/97

YO997-114

08/909,719

08/12/97

YO995-109B

(allowed)

08/935,989

10/23/97

YO997-310

The following further documents are also incorporated herein by reference in their entirety:

IBM Technical Disclosure Bulletin

IBM Technical Disclosure Bulletin: Vol. 38 No. 08, August 1995, page 17, “Multifunction Credit Card Package,” by Brady, Moskowitz, and Murphy (published anonymously).

Literature Reference

D. Friedman, H. Heinrich, D. Duan, “A low-power CMOS integrated circuit for field-powered radio frequency identification (RFID) tags,” 1997 Digest of Technical Papers of the IEEE International Solid-State Circuits Conference (ISSCC), San Francisco, Calif., February 1997.

PCT Published International applications Ser. Nos.

Application Ser. No.

Filing Date

Attorney Docket No.

PCT/GB96/00061

01/15/96

UK 9-94-066 PCT

PCT/EP95/03703

10/20/95

YO994-242 PCT

PCT Published International applications Ser. Nos.

Application Ser. No.

Filing Date

Attorney Docket No.

PCT/GB96/00061

01/15/96

UK 9-94-066 PCT

PCT/EP95/03703

10/20/95

YO994-242 PCT

FIELD OF THE INVENTION

The present invention relates generally to radio frequency identification (RFID) systems, and more specifically to RFID tags integrated into electronic assets.

BACKGROUND OF THE INVENTION

Radio Frequency Identification (RFID) is becoming an important identification technology in applications such as inventory management, security access, personnel identification, factory automation, automotive toll debiting, and vehicle identification to name just a few. RFID systems utilize an RFID transmitter-receiver unit (usually referred to as a base station or interrogator) to query an RFID transponder or tag which may be located at a distance from the transmitter-receiver unit. The RFID tag detects the interrogating signal and transmits a response signal containing encoded data back to the receiver.

RFID systems provide identification functions not found in identification technologies such as optical indicia (e.g., bar code) recognition systems. For example, RFID systems may employ RFID tags containing read/write memory of several kilobytes or more. The RFID tags may be readable at a distance and do not require direct line-of-sight view by the reading apparatus (e.g., base station or interrogator). Further, several such RFID tags may be read by the RFID system at one time.

Manufacturers and users of assets such as electronic components, devices, and systems have a need for an efficient means of tracking information about these assets in order to, for example, verify ownership, provide warranty information, prevent counterfeiting of parts, and provide theft recovery. Presently, such information is tracked by placing a serial number on the asset and storing this serial number along with information about the asset in a large, centralized database, typically the database of the manufacturing entity. However, due to the often large size of such a database or a use's inability to efficiently access the database, essential information such as identification (i.e., serial number) for inventory tracking or theft recovery, servicing information (i.e., time of assembly and/or sale, date of last service, date when next service is due, etc) and the like may be difficult to access and track.

Consequently, it would be desirable to apply RFID technology to electronically store information about an asset such as an electronic component, device, or system within the asset in order to provide functions such as, for example, assuring security of the assets, inventory tracking of the assets, identification of the assets, and short distance communication between the assets.

SUMMARY OF THE INVENTION

Accordingly, the present invention employs RFID technology to store and provide information about assets such as electronic components, devices, and systems in order to provide functions such as, for example, assuring security of the assets, inventory tracking of the assets, identification of the assets, and short distance communication between the assets. The present invention may be applied at the component level (i.e., circuit chip, circuit board, drive, motherboard, etc.), the device level (i.e., box, computer, monitor, server, etc.), or the system level (i.e., network system, computer system, etc.).

In accordance with a first aspect of the present invention, RFID technology is applied at the chip level. An electronic component such as a packaged integrated circuit (IC) includes an integrated RF transponder for communicating information about the component to an RFID system. The packaged IC comprises a package having a plurality of external leads or pins electrically coupled to one or more integrated circuits contained therein. One or more host or primary integrated circuit chips are housed within the package and electrically coupled to the leads as necessary. A radio frequency integrated circuit (RFID IC) comprising memory for storing information about the electronic component and an RF transmitter and receiver section for communicating the information to the RFID system is housed within the package. The RF transmitter and receiver section may operate by modulating a reflected RF signal. The RFID IC may be a separate chip housed within the package and electrically coupled to at least one of the leads (for connection of an antenna) of the package, or alternatively, may be integrated monolithically with the primary IC.

The present invention may similarly be applied at the circuit board level. An electronic component comprising a circuit board may include an integrated RF transponder for communicating information about the component to an RFID system. The circuit board comprises a substrate having mounted thereon one or more packaged IC's operable to provide the functions of the component. An RF transponder circuit is mounted to the substrate. The RF transponder circuit includes memory for storing information about the electronic component and an RF transmitter and receiver section for communicating the information to the RFID system. The RF transponder circuit may be a packaged IC mounted to the substrate and coupled to an antenna formed on the substrate, or to an externally supplied antenna, pluggable antenna, detachable antenna, etc. via a connector. Alternatively, one or more of the IC's mounted to the substrate may include an integrated RFID IC. Each of these RFID IC's may be coupled to a separate antenna or may be coupled to and share a common antenna via a switching circuit.

According to a further aspect of the present invention, RFID technology is applied at the device level. An electronic device includes electronic components (i.e., a circuit board, a motherboard, a disc drive, etc.) configured to provide a function of the electronic device and an RF transponder. The RF transponder may be mounted to the electronic component or to the device's housing. The RF transponder includes memory forstoring information about the electronic device and an RF transmitter and receiver section for providing communication of the information with the RFID system. The RF transponder may be programmed with information about the device and/or, optionally, components within the device.

In accordance with yet another aspect of the present invention, RFID technology is applied to the system level to provide an information handling system capable of communicating information to an RFID system. The information handling system includes a plurality of electronic devices each configured to provide one or more of the functions of the information handling system. An RF transponder is provided by at least one of said electronic devices. The RF transponder includes memory for storing information about the information handling system, an RF transmitter and receiver section for providing communication of the information with the RFID system, and an antenna coupled to the RF transmitter and receiver section. The RF transponder may then be programmed with information about the system, devices within the system, and components within each device of the system.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The numerous objects and advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which:

FIG. 1

is a block diagram depicting of a typical radio frequency identification (RFID) system;

FIGS. 2A and 2B

are top plan views illustrating the application of the present invention at the chip level;

FIG. 2A

depicts a host integrated circuit (IC) chip and radio frequency identification integrated circuit (RFID IC) chip packaged together in a plastic-molded package;

FIG. 2B

depicts an integrated circuit (IC) chip which includes a radio frequency identification (RFID) circuit integrated monolithically therein wherein the IC is packaged in a plastic-molded package;

FIGS. 3A

,

3

B,

3

C, and

3

D are top plan views illustrating the application of the present invention at the component (i.e., circuit board) level;

FIG. 3A

depicts a printed circuit board comprising an RF transponder including an RFID IC and an antenna which is formed as an integral part of the circuit board;

FIG. 3B

depicts a printed circuit board comprising an RF transponder including an RFID IC mounted thereon and interconnected to an externally provided antenna via a circuit board mounted coupling device;

FIG. 3C

depicts a printed circuit board comprising an RF transponder including an RFID IC and an antenna which is formed as an integral part of the circuit board, wherein the RFID IC is inter-connected with electronic elements and circuits mounted on the circuit board;

FIG. 3D

depicts a printed circuit board including multiple integrated circuits having integral RFID IC's;

FIGS. 4A

,

4

B,

4

C,

4

D, and

4

E are isometric views illustrating the application of the present invention at the device or “box” level;

FIG. 4A

depicts an electronic device comprising a plurality of electronic components (i.e., circuit boards) wherein one or more of the components includes an integral RFID transponder;

FIG. 4B

depicts an electronic device having a single RF transponder mounted therein;

FIG. 4C

depicts an electronic device having a primary circuit board or “motherboard” which comprises an integral RF transponder including an RFID IC and an antenna integrally formed on the motherboard;

FIG. 4D

depicts an electronic device having a primary circuit board or “motherboard” wherein the RF front-end section and antenna of the RF transponder are mounted on the device's housing while the remaining RFID circuits are mounted on the motherboard;

FIG. 4E

depicts an electronic device comprising a primary circuit board or “motherboard” and RF transponder including an RFID IC mounted to the motherboard and coupled to an externally provided antenna via a connector;

FIG. 4F

depicts an electronic device wherein the RF transponder is coupled directly to an interrogator via a connector and cable;

FIG. 4G

depicts an electronic device comprising a primary circuit board or “motherboard,” RF transponder, and dual antenna assembly;

FIG. 4H

is a cross-sectional side elevational view of the dual antenna assembly.

FIGS. 5A and 5B

are isometric views illustrating the application of present invention at the system level;

FIG. 5A

depicts a system wherein each electronic device includes at least one RF transponder mounted thereto; and

FIG. 5B

depicts a system utilizing a single system level RF transponder.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the presently preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings.

Referring now to

FIG. 1

, a typical RFID system is shown. The RFID system

100

includes an interrogator or base station

112

communicating an RF signal to an RFID transponder

114

. The interrogator

112

preferably includes RF transmitter and a receiver sections

116

&

118

for providing two way communication with the RFID transponder

114

. The transmitter section

116

preferably includes an RF source

120

and RF amplifier

122

which send RF power to an antenna

124

. The transmitter section

116

transmits an RF signal with a transmitter carrier frequency. The transmitter carrier also has a transmitting carrier frequency bandwidth referred to as a transmitting bandwidth. The transmitting bandwidth is preferably wide enough to transmit data at a desired rate.

The RFID transponder

114

comprises an antenna

126

and an RFID circuit

128

including an RF processing section (typically referred to as a front end)

130

and a signal processing section

132

. The front end

130

can be any known front end design used with an antenna. The front end

130

may include a transmitter

134

and a receiver

136

. Examples of front ends are well known. See, for example, the Hewlett Packard “Communications Components GaAs & Silicon Products Designees Catalog” (i.e., page 2-15) which is herein incorporated by reference in its entirety. A typical front end is also described in U.S. patent application Ser. No. 08/790,639 to Duan, et al. filed Jan. 29, 1997 which is herein incorporated by reference in its entirety. The signal processing section

132

may include logic circuits and memory for processing and storing information.

The present invention employs RFID technology to store and provide information about assets such as electronic components, devices, and systems. In this manner, functions such as, for example, security of the assets, inventory tracking of the assets, identification of the assets, and short distance communication between the assets. The present invention may be applied at the component level (i.e., circuit chip, circuit board, drive, motherboard, etc.), the device level (i.e., box, computer, monitor, server, etc.), or the system level (i.e., network system, computer system, etc.).

Referring now to

FIGS. 2A and 2B

, application of the present invention at the chip level is shown. A packaged integrated circuit (IC)

200

includes an integrated RFID circuit

212

for communicating information about the IC

200

to an RFID system (such as the RFID system shown in FIG.

1

). The packaged IC

200

preferably comprises a host IC chip (i.e., a micro-processor, a micro-controller, a video codec, a memory device, etc.)

214

encapsulated within a plastic-molded package

216

. The package

216

may be a single in-line package (SIP), dual in-line package, or flat pack (shown). The preferred package is determined mostly by the host IC

214

. Typical IC packages include, but are not limited to SOP, MSOP, SOIC, PBGA, TQFP, LQFP, MQFP, PQFP, PLCC, TSSOP, SSOP, QSOP, MICRO, PDIP, and POWER packages. Preferably, the package

216

includes a plurality of external leads or pins

218

which are electrically coupled as required by the IC design to the host IC chip

214

via conventional techniques such as wire bonding or the like.

As shown in

FIG. 2A

, the RFID circuit

212

may be a radio frequency identification integrated circuit (RFID IC)

220

. The RFID IC

220

preferably comprises an RF processing section (e.g., a front end) and a signal processing section including logic circuits and memory for storing information about the packaged IC

200

. In this manner, information may be transmitted to the RFID IC

220

where it is written to the memory and stored. When the RFID IC

220

is later interrogated by the RFID system, the stored information may be recalled from memory to be read by the interrogator or base station (see FIG.

1

).

The RFID IC

220

may be a separate chip, as shown in

FIG. 2A

, which is encapsulated within the package

216

adjacent to the host IC chip

214

to form a multi-chip module. The RFID IC

220

may be electrically coupled to at least one of the leads

218

of the package

216

(e.g., for connection to an antenna, a power source, etc.). Preferably, the RFID IC

220

is electrically coupled to the host IC chip

214

via conventional techniques such as wire bonding. This allows the RFID IC

220

to communicate information directly with, and to receive electrical power via the host IC chip

214

. The RFID IC

220

may alternately operate separately from the host IC

214

(e.g., the RFID IC

220

is not electrically coupled to the host IC chip

214

). One or more leads

218

may to which the RFID IC

220

is connected, may couple the front end of the RFID IC to an externally provided antenna (see FIG.

3

A). Alternatively, an antenna may be formed in the host IC chip

214

, package

216

, or RFID IC

220

.

As shown in

FIG. 2B

, the RFID circuit

212

may alternatively be integrated monolithically within the host IC chip

214

. One or more leads

218

to which the host IC chip

212

is connected, may be dedicated to coupling the RFID circuit

212

to an externally provided antenna (see FIG.

3

A). Alternatively, an antenna may be formed in the host IC chip

214

or the package

216

.

The RFID equipped packaged IC

200

may provide functions such as, for example, assuring security of the assets, inventory tracking of the assets, identification of the assets, and short distance communication between the assets. For example, the host IC chip

214

of the packaged IC

200

may be a microprocessor of a personal computer system. Such a microprocessor, if it possesses desirable characteristics (i.e., high speed, efficient design, etc.) and is in limited supply, may be highly desirable and subject to theft. An RFID system (see

FIG. 1

) may be utilized to prevent removal of the microprocessorfrom the premises (i.e., factory, warehouse, office, etc.) where it is stored, or used. For example, an office employing a large number of advanced computer systems equipped with the described microprocessor may utilize interrogators located near exits to warn if a microprocessor is being removed. Similarly, the micro-processor may be designed so that it will not function properly unless it is enabled or “activated” in the manufacturer's facility. In an exemplary embodiment, the microprocessor may be activated by a base station which transmits an “unlock” command to the RFID circuit

212

. The unlock command may flip the state of a locklunlock bit within the microprocessor or the RFID IC which controls the activities of other circuits within the microprocessor. Alternatively, sophisticated keyed encryption architectures may be used to secure the transactions between the authorizing base station and the RFID IC.

Referring now to

FIGS. 3A through 3D

, application of the present invention at the circuit board level is shown. An electronic component (i.e., an expansion board for a computer, a disk drive, a hard disk drive, etc) may comprise a printed circuit board

300

containing an integrated RFID transponder

312

for communicating information about the electronic component to the RFID system (see FIG.

1

). The circuit board

300

preferably includes a substrate

314

formed from a phenolic, epoxy, or similar dielectric material, on which electrical and electronic elements (i.e. integrated circuits (IC), transistors, resistors, capacitors, etc.)

316

are mounted in the construction of a circuit. The circuit board

300

may have an etched copper foil pattern

318

on one (single sided), both sides (double sided), and/or between layers of dielectric material of the substrate

314

for the purpose of interconnection of elements

316

mounted to the substrate

314

.

Electronic elements

316

mounted on the circuit board

300

may include one or more packaged integrated circuits (IC)

320

. As described, supra, in connection with the description of

FIGS. 2A and 2B

, each packaged IC

320

preferably comprises at least one IC chip (i.e., a micro-processor, a micro-controller, a video codec, a memory device, etc.) encapsulated within a plastic-molded package

322

. The package

322

may be a single in-line package (SIP), dual in-line package, or preferably a flat pack (shown). Typical flat pack IC packages which may be utilized by the present invention include, but are not limited to SOP, MSOP, SOIC, PBGA, TQFP, LQFP, MQFP, PQFP, PLCC, TSSOP, SSOP, QSOP, MICRO, PDIP, and POWER packages. Preferably, the package

322

includes a plurality of external leads or pins

340

which electrically couple the packaged IC

320

to the copper foil pattern

318

.

As shown in

FIGS. 3A

,

3

B, and

3

C, the RFID transponder

312

preferably includes a packaged radio frequency identification integrated circuit (RFID IC)

324

mounted to the substrate

314

of the circuit board

300

. The package

326

of the RFID IC

324

may be a single in-line package (SIP), dual in-line package, or preferably a flat pack (shown). Typical, packages which may be utilized by the present invention include, but are not limited to SOC, MSOP, SOIC, PBGA, TQFP, LQFP, MQFP, PQFP, PLCC, TSSOP, SSOP, QSOP, MICRO, PDIP, and POWER packages. The RFID IC

324

comprises an RF processing section (e.g., a front end) and a signal processing section including logic circuits and memory for storing information about the electronic component. In this manner, information may be transmitted to the RFID transponder

312

where it is written to the memory of the RFID IC

324

and stored. When the RFID transponder

312

is later interrogated by the RFID system, the stored information may be recalled from memory to be read by the interrogator or base station (see FIG.

1

).

As shown in

FIGS. 3A and 3C

, the RFID IC

324

may be interconnected with an antenna

328

integrally formed on the substrate

314

of the circuit board

300

. Preferably, the antenna

328

comprises thin, typically

18

to

35

micron thick, lines formed of a conductive metal such as copper. These lines may be formed by plating, adhering orscreening a thin layerofcopper(orotherconductive metal) onto to the substrate

314

. This layer may then be etched to form the specific geometric configuration (i.e., monopole, dipole, folded dipole, meander dipole, patch, slot, loop, spiral, etc.) of the antenna

328

. One or more impedance adjustment elements

330

&

332

may be integrally formed on the substrate

314

to modify the impedance of the antenna

328

. The impedance adjustment elements

330

&

332

may be lumped circuit elements, distributed microwave circuit elements, or parasitic elements that are electromagnetically coupled to the antenna (i.e., not electrically connected). For example, the antenna

328

may include a tuning stub

330

having a length and width adjusted to tune the impedance of the antenna

328

. The tuning stub

330

acts as a two conductor transmission line and may be terminated either in a short-circuit or open-circuit. A short circuited stub acts as a lumped inductor while an open-circuit stub acts as a lumped capacitor. The magnitude of the reactance of the stub is affected by the stub's length, width, and spacing. Similarly, one or more impedance loading bars

332

may be positioned on the substrate

314

adjacent to the antenna

328

. Use of impedance adjustment elements such as tuning stubs and impedance loading bars to adjust the impedance of an antenna is described in detail in U.S. patent application Ser. No. 08/790,639 to Duan, et al. filed Jan. 29, 1997 which is herein incorporated by reference in its entirety.

As shown in

FIG. 3B

, the RFID IC

324

may alternatively be mounted to the substrate

314

and coupled to a detachable externally provided antenna

334

via a coupling device or connector

336

. The externally provided antenna

328

may, for example, be formed on another circuit card, mounted to a device containing the circuit card

300

holding the RF transponder

312

, or remotely located (i.e., attached to the roof of a building housing an electronic device containing the circuit card

300

). Preferably, the coupling device

336

is also mounted to the substrate

314

.

As shown in

FIG. 3C

, the RFID IC

324

may be electrically interconnected to other electronic elements or circuits

316

mounted to the circuit board

300

. When the RFID IC

324

is not inter-connected to other electronic elements or circuits

316

(as shown in FIG.

3

A), it will typically contain only a unique identification number and perhaps some information about the circuit board

300

being identified. However, when the RFID IC

324

is inter-connected one or more electronic elements

316

, it may provide additional functions such as identification of electronic elements

316

mounted to the circuit board

300

. For example, two or more versions of a processor may be mounted to the same type of circuit board. An RFID IC mounted to the circuit board and interconnected with the processor may receive information, from the processor identifying which version it is, via the interconnection. The RFID IC may then transmit this information to the RFID system in real time via, for example, a base station to identify the version of the processor mounted on the board during the inventory or assembly processes.

In an alternative embodiment shown in

FIG. 3D

, one or more packaged IC's

320

may include an RFID IC

324

integrated therein as described in the discussion of

FIGS. 2A and 2B

. For example, the RFID IC

324

may comprise a separate IC chip encapsulated within the package

322

adjacent to a host IC chip to form a multi-chip module (see FIG.

2

A). The RFID IC chip may be electrically coupled to at least one of the leads

340

of the package (e.g., for connection of an external antenna, power, etc.). Preferably, the RFID IC

324

is electrically coupled to the host IC via conventional techniques such as wire bonding or the like. The RFID IC

324

may also operate separately from the host IC (e.g., the RFID IC is not electrically coupled to the host IC). Alternatively, the RFID IC

324

may comprise a circuit integrated monolithically within the host IC chip (see FIG.

2

B). Specified leads

340

to which the host IC chip is coupled may be dedicated to coupling the RFID circuit to an antenna assembly

338

.

Wherein more than one packaged IC

320

mounted to the circuit board

314

contains an RFID IC

324

, the antenna assembly may include a separate antenna for each RFID IC

324

. These antennas may be mutually coupled, or decoupled (e.g., independent) if sufficient space is provided between them on the circuit board. Alternatively, one or more of the RFID IC's

324

may share a common antenna. A switching network, which may be built into the antenna assembly

338

, and a switch algorithm may be used to schedule usage of the antenna by the various RFID IC's

324

.

Referring now to

FIGS. 4A through 4F

, application of the present invention at the device or “box” level is shown. An electronic device

400

such as a computer, network server, etc. may include a plurality of electronic components

412

. The electronic components

412

are preferably configured to provide functions of the device

400

. Typical electronic components

412

which may be contained in an electronic device in accordance with the present invention include, but are not limited to, circuit boards (shown in FIG.

4

A through

4

G), primary circuit cards or “motherboards” (shown in FIGS.

4

B through

4

G), power supplies, memory devices (i.e., a magnetic disk drive, an optical disc drive, etc.), ports, displays, and data entry devices (i.e., keyboards, keypads, pointing devices, etc.).

The electronic device

400

may include a means of interconnection (e.g., a primary circuit board or “motherboard”)

430

to which other electronic components

412

(and various electronic elements, such as processors, memory IC's, etc.) may be mounted and electrically connected (FIGS.

4

B through

4

F). RFID transponders

414

&

420

may be useful during assembly, inventory, and delivery (including loading and receiving) of such electronic devices. For example, the RFID transponder may be programmed to contain the serial number, part number, and warranty information of the electronic device

400

. Optionally, the RFID IC's memory may also contain part numbers, serial numbers, installation dates, warranty and information for components

412

contained within the device

400

.

Turning now to

FIG. 4A

, one or more of the electronic components

412

contained within the device

400

may include an RFID transponder

414

. For example, for electronic components

412

comprising circuit boards

416

(shown) the RFID transponder

414

may be integrated within the circuit board

416

as described in the discussion of

FIGS. 3A through 3D

, supra. For other types of electronic components

412

(i.e., disc drives, power supplies, etc. not shown), the RFID transponder

414

may be attached to the component via a fastener such as an adhesive, rivets, screws, and the like. Altematively, these components may include a circuit board having an integrated RFID transponder (see

FIGS. 2A through 2D

, supra).

The RFID transponder

414

of each RFID equipped electronic component

412

may include a radio frequency identification integrated circuit (RFID IC)

416

and antenna

418

. The RFID IC

416

preferably comprises an RF processing section (e.g., a front end) and a signal processing section including logic circuits and memory for storing information. Each RFID transponder

414

may in this manner be programmed with information about the electronic device

400

and, optionally, the electronic components

412

within the device

400

. This information may be transmitted to the RFID system (see

FIG. 1

) via an interrogator or base station using an antenna which probes the interior of the device's housing, or using an antenna placed outside of the housing which communicates with the RFID transponders

414

within the device

400

via a frequency selected surface (FSS). See U.S. Pat. No. 5,767,789 to Afzali-Ardakani et al., issued Jun. 16, 1998, which is herein incorporated by reference in its entirety.

Alternatively, as shown in

FIGS. 4B through 4E

, a single “device-level” RFID transponder

420

may be mounted within the housing

422

of the electronic device

400

. The device-level RFID transponder

420

may function in place of or in conjunction with the circuit board mounted RFID transponders described in the discussion of FIG.

4

A. Preferably, the device-level RFID transponder

420

is configured to communicate with an RFID system via the system's base unit or a handheld interrogator (see FIG.

1

).

As shown in

FIG. 4B

, the RFID transponder

420

may be attached to an interior surface of the housing

422

via a fastener such as an adhesive, double sided tape, rivets, bolts, or the like. The RFID transponder

420

preferably includes a packaged radio frequency identification integrated circuit (RFID IC)

424

mounted to a substrate

426

and bonded to an antenna

428

. Preferably, the RFID IC

424

comprises an RF processing section (e.g., a front end) and a signal processing section including logic circuits and memory for storing information. The RFID transponder

420

may be electrically interconnected to the motherboard

430

of the electronic device via a wire, cable, flexible circuit, or the like. In this manner, the RFID transponder

424

may be programmed with information about the electronic device

400

and, optionally, the electronic components

412

within the device

400

. This information may be transmitted to the RFID system (see

FIG. 1

) via an interrogator or base station using an antenna which probes the interior of the device's housing, or using an antenna placed outside of the housing which communicates with the RFID transponders

420

within the device

400

via a frequency selected surface (FSS). See U.S. Pat. No. 5,767,789 to Afzali-Ardakani et al., supra.

Substrate materials on which the RFID IC

424

may be mounted include polyester, polyimide, ceramics, FR-4 epoxy, phenolic, and like dielectric materials. The packaged RFID IC

424

preferably comprises an RFID IC chip encapsulated within a plastic-molded package. The package may be a single in-line package (SIP), dual in-line package, or a flat pack. Typical flat pack IC packages which may be employed by the present invention include, but are not limited to SOC, MSOP, SOIC, PBGA, TQFP, LQFP, MQFP, PQFP, PLCC, TSSOP, SSOP, QSOP, MICRO, PDIP, and POWER packages. Preferably, the package includes a plurality of external leads or pins (not shown). Two of the leads may electrically couple the RFID IC

424

to the antenna

428

formed on the substrate

426

(i.e., the leads may be soldered to the antenna

428

using conventional soldering techniques). Alternatively, a non-packaged RFID IC chip (not shown) may be directly mounted to the substrate

426

and bonded to the antenna

428

. The non-packaged RFID IC chip may be coated with an encapsulant, such as a “glob-top” epoxy, or the like and/or laminated with a laminate to protect the chip (and bonds between the antenna and chip) from damage.

The antenna

428

may be integrallyformed on the substrate

426

. Preferably, the antenna

428

comprises thin, typically

18

to

35

micron thick, lines formed of a conductive metal such as copper. These lines may be formed by plating, adhering or screening a thin layer of copper (or other conductive metal) onto to the substrate

426

. This layer may then be etched to form the specific geometric configuration (i.e., monopole, dipole, folded dipole, meander dipole, patch, slot, loop, spiral, etc.) of the antenna

428

. One or more impedance adjustment elements (see

FIG. 3A

) may be integrally formed on the substrate

426

to modify the impedance of the antenna

428

. The impedance adjustment elements may be lumped circuit elements, distributed microwave circuit elements, or a parasitic element that is electromagnetically coupled to the antenna (i.e., not electrically connected).

As shown in

FIG. 4C

, the RF transponder

420

including the RFID IC

424

and antenna

428

may alternatively be integrated on the motherboard

430

. This may be accomplished by using the methods and apparatus for mounting an RFID transponder onto a printed circuit board as described in the discussion of

FIGS. 3A through 3D

, supra. Preferably, the RFID transponder

420

is electrically interconnected with other electronic elements and components

412

coupled to the motherboard

430

. The RFID transponder

424

may be programmed with information about the electronic device

400

and, optionally, the electronic components

412

within the device

400

. This information may be transmitted to the RFID system (see

FIG. 1

) via an interrogator or base station using an antenna which probes the interior of the device's housing, or using an antenna placed outside of the housing which communicates with the RFID transponders

414

within the device

400

via a frequency selected surface (FSS). See U.S. Pat. No. 5,767,789 to Afzali-Ardakani et al., supra.

Turning now to

FIG. 4D

, an embodiment of the present invention is shown wherein the RF front-end

432

and antenna

438

of the RFID transponder

420

are mounted on the electronic device's housing

422

while the signal processing section

434

while other circuits of the RFID transponder

420

are mounted on the motherboard

430

. The RF front-end

432

and the signal processing section

434

of the RFID transponder

420

may, for example, be separately packaged (i.e., in a single in-line package (SIP), dual in-line package, flat pack, etc.). The front-end

432

may be mounted to a circuit board or substrate

436

and interconnected with an antenna

438

. The antenna

438

may be integrally formed on the substrate

436

(i.e., via etching, screening, etc.) or may be externally provided. The substrate

436

may be secured to the housing

422

via a fastener such as adhesive, rivets, screws, etc., or, alternatively, mounted separately from the motherboard

430

within the housing

422

and interconnected to the signal processing section

434

mounted to the motherboard

430

via a wire or cable

440

.

As shown in

FIGS. 4E and 4F

, the RFID transponder

420

may have only its antenna

442

externally mounted, while its RFID IC

424

is mounted to the motherboard

430

of the electronic device

400

. As shown in

FIG. 4E

, an RF cable (i.e., a coaxial cable)

444

may interconnect the RF front-end of the RFID IC

424

to an antenna

442

mounted to the device's housing