HK1159327B - An inverted-f antenna and a handheld electronic device - Google Patents

Description

inverted-F antenna and handheld electronic device

Since apple iPhone 4 prototype, an engineer, 3.25.2010, was stolen (as known by apple), the invention to be disclosed and protected by this application was prematurely disclosed to the public and not authorized by apple. The U.S. priority application on which this application is based is filed after a theft event known to apple inc.

Technical Field

The present invention relates generally to wireless communication circuits, and more particularly to electronic devices having wireless communication circuits.

Background

Electronic devices such as computers and handheld electronic devices are becoming increasingly popular. Such devices are typically provided with wireless communication capabilities. For example, the electronic device may communicate using long range wireless communication circuitry, such as cellular telephone circuitry using cellular telephone frequency bands. The electronic device may handle communications with nearby equipment using a short-range wireless communication link. For example, the electronic device can be used at 2.4GHz and 5GHz(IEEE 802.11) frequency band and at 2.4GHzFrequency bands to communicate. Some devices also incorporate wireless circuitry that receives Global Positioning System (GPS) signals at 1575 MHz.

To meet consumer demand for miniaturized wireless devices, manufacturers are continually striving to implement wireless communication circuits, such as antenna assemblies, in compact configurations. Also, device housing assemblies that contain conductor structures, such as metals, may be desirable in electronic devices. Because conductor components can affect radio frequency performance, care must be taken when incorporating antennas into electronic devices containing conductor structures.

Accordingly, there is a need for improved wireless communication circuitry for wireless electronic devices.

Disclosure of Invention

An electronic device having an antenna structure is provided. The inverted-F antenna may be configured to operate on the first and second communication bands. The electronic device may include radio-frequency transceiver circuitry coupled to an antenna using a transmission line. The transmission line may have a positive conductor and a ground conductor. The antenna may have a positive antenna feed terminal and a ground antenna feed terminal and be coupled to the positive conductor and the ground conductor of the transmission line, respectively.

The electronic device may have a rectangular outer perimeter. A rectangular display may be mounted on the front of the electronic device. The conductive sidewall structure may surround the outer perimeter of the housing and display of the electronic device. The conductive sidewall structure may serve as a bezel for the display.

The bezel may include at least one notch. The gap may be filled with a solid insulator, such as plastic. The antenna may have one main resonating element arm. The resonator element arm may be folded at a bend. The first section of the resonating element arm may be formed from a portion of the bezel. The second part of the resonant element arm may be formed by a conductive trace on the insulating member. A spring adjacent the bend may be used to connect the first and second parts of the resonator element arm. The bend may be located at a notch of the bezel.

First and second parallel shorting legs may connect the antenna resonating element arm to ground. The feed leg may be connected between the antenna resonating element and the first antenna feed terminal. The second antenna feed terminal may be connected to ground. The first shorting leg may be formed by a portion of the bezel.

According to one embodiment, there is provided an inverted-F antenna in an electronic device having an outer periphery, including: a resonating element arm formed at least in part by a conductive structure on an outer periphery; a feed leg connected to the resonating element arm; a ground; a shorting leg connecting one end of the resonant element arm to the ground; a first antenna feed terminal connected to the feed leg; and a second antenna feed terminal coupled to the ground.

According to one embodiment, there is provided an inverted-F antenna in an electronic device having a peripheral side, including: a resonant element arm formed at least in part by a section of conductive shell structure arranged along one of the sides; a ground; and a shorting leg connecting the resonating element arm to the ground.

According to one embodiment, there is provided a handheld electronic device having four sides, comprising: a conductive bezel extending along each of the four sides, wherein the conductive bezel has at least one notch; an inverted-F antenna having an antenna resonating element formed from a segment of the conductive bezel adjacent the gap.

Other features, characteristics and various advantages of the present invention will become more apparent from the attached drawings and the following detailed description of the preferred embodiments.

Drawings

FIG. 1 is a perspective view of an illustrative electronic device having wireless communication circuitry in accordance with an embodiment of the present invention.

Fig. 2 is a schematic diagram of an illustrative electronic device having wireless communication circuitry in accordance with one embodiment of the present invention.

Fig. 3 is a cross-sectional view of an illustrative electronic device having wireless communication circuitry in accordance with one embodiment of the present invention.

Fig. 4 is an illustration of an exemplary inverted-F antenna in accordance with one embodiment of the present invention.

Fig. 5 is a schematic diagram of an illustrative folded inverted-F antenna in accordance with one embodiment of the present invention.

Fig. 6 is a top view of an electronic device showing how the electronic device is provided with a folded inverted-F antenna with a shorting leg according to one embodiment of the present invention.

Fig. 7 is a smith chart showing the performance of an antenna of the type in fig. 6 according to one embodiment of the present invention.

Fig. 8 is a graph illustrating the performance of an antenna of the type in fig. 6 without shorting legs according to one embodiment of the present invention.

Fig. 9 is a graph illustrating the performance of an antenna of the type in fig. 6 in the presence of a shorting leg, in accordance with one embodiment of the present invention.

Fig. 10 is a top view of an illustrative electronic device that includes the antenna shown in fig. 6 formed using portions of a conductive bezel that surrounds the outer perimeter of the electronic device in accordance with one embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The electronic device may have wireless communication circuitry. The wireless communication circuit may be configured to support wireless communications in a plurality of wireless communication bands. The wireless communication circuitry may include one or more antennas.

The antenna may comprise an inverted-F antenna. An inverted-F antenna in an electronic device may include a folded arm. The use of a folding arm may help to minimize the size of the antenna. The short circuit structure in the inverted-F antenna can improve the performance of the antenna by allowing the antenna to operate efficiently in a variety of communication bands.

The conductive structure for the inverted-F antenna may be formed of a conductive electronic device structure, if desired. The conductive electronic device structure may include a conductive housing structure. The housing structure may include a conductive structure around the periphery of the device. The structure may take the form of a conductive metal strip around all four sides of the device. The display and other components may be mounted on the device under the constraints of the metal strap. In this regard, the metal strip may act as a bezel and is therefore sometimes referred to herein as a bezel or conductive bezel structure.

A notch structure can be formed in the frame. The presence of the notch may, for example, help define the location of the fold in the folded inverted-F antenna resonating element arm.

Any suitable electronic device may have wireless circuitry including an inverted-F antenna structure based on a conductive device structure, such as a device bezel. As an example, this type of inverted-F antenna structure may be used in electronic devices such as desktop computers, game consoles, routers, laptop computers, and the like. In one suitable configuration, a bezel-based inverted-F antenna structure is used in a relatively compact electronic device (e.g., a portable electronic device) where internal space is relatively valuable.

FIG. 1 shows an illustrative portable electronic device in accordance with one embodiment of the invention. A portable electronic device, such as the illustrative portable electronic device 10 in fig. 1, may be a laptop computer or a small portable computer, such as an ultra-portable computer, a netbook computer, and a tablet computer. The portable electronic device may also be some smaller device. Examples of smaller portable electronic devices include watch devices, pendant devices, earphone and ear bud (ear) devices, and other wearable and miniature devices. In one suitable arrangement, the portable electronic device is a handheld electronic device, such as a cellular telephone.

In portable electronic devices, space is at a premium. And typically presents challenges in conductive structures that can make antennas work efficiently. For example, the conductive housing structure may surround part or all of the periphery of the portable electronic device housing.

In configurations such as portable electronic device housings, it is particularly beneficial to utilize an inverted-F antenna in which a portion of the antenna is formed of a conductive housing structure. Thus, the portable devices described herein, such as handheld devices, are used as examples, but any suitable electronic device may have an inverted-F antenna structure, if desired.

The handheld devices may be, for example, cellular telephones, media players with wireless communication capabilities, handheld computers (also sometimes referred to as personal digital assistants), remote controllers, Global Positioning System (GPS) devices, and handheld gaming devices. Handheld and other portable devices may include a variety of conventional device functions, if desired. Examples of multifunction devices include cellular telephones having media player capabilities, gaming devices having wireless communication capabilities, cellular telephones having gaming and email capabilities, and handheld devices that can accept mail, support mobile telephone calls, and support web browsing. These are merely illustrative examples. The device 10 of fig. 1 may be any suitable portable or handheld electronic device.

The device 10 includes a housing 12 and includes at least one antenna for handling wireless communications. The housing 12, sometimes referred to as a shell, may be formed from any suitable material, including plastics, glass, ceramics, carbon fiber composite and other composite materials, metals, other suitable materials, or combinations of these materials. In some cases, portions of the housing 12 may be formed of an insulator or other low-conductivity material such that the operation of the conductive antenna elements located within the housing 12 is not disturbed. In other cases, the housing 12 may be formed from a metal element.

If desired, device 10 may have a display, such as display 14. The display 14 may be, for example, a touch screen incorporating capacitive touch electrodes. Display 14 may include image pixels formed from Light Emitting Diodes (LEDs), Organic LEDs (OLEDs), plasma, electronic ink elements, Liquid Crystal Display (LCD) components, or other suitable image pixel structures. The cover glass assembly may cover the surface of display 14. A button (e.g., button 19) may pass through an opening in the cover glass.

The housing 12 may include a sidewall structure, such as housing sidewall structure 16. Structure 16 may be implemented using a conductive material. For example, structure 16 may be implemented using a conductive ring-shaped member that substantially surrounds the rectangular periphery of display 14. Sometimes this structure forms a band around the periphery of the device 10, so sometimes the sidewall structure 16 may be referred to as a band structure, band member, or band.

The structure 16 may be formed of a metal, such as stainless steel, aluminum, or other suitable material. One, two, or more than two separate structures may be used to form structure 16. Structure 16 may act as a bezel to secure display 14 to the front (top) surface of device 10. Accordingly, structure 16 is sometimes referred to herein as bezel structure 16 or bezel 16.

Bezel 16 surrounds the rectangular perimeter of device 10 and display 14. Bezel 16 may be limited to an upper portion of device 10 (i.e., a peripheral region proximate to the surface of display 14) or may cover the entire longitudinal height of the sidewalls of device 10 (e.g., as in the example shown in fig. 1). Other configurations are also possible, such as configurations in which the bezel 16 or other sidewall structure is partially or fully integrated with the back wall of the housing 12 (e.g., in an integral fuselage configuration).

The bezel (ribbon) 16 may have a thickness (dimension TT) of about 0.1mm to 3mm (as an example). The sidewall portions of the rim 16 may be substantially vertical (parallel to the vertical axis V) or curved. In the example of fig. 1, the bezel 16 has a relatively flat outer surface. Parallel to axis V, bezel 16 may have a dimension TZ of between 1mm and 2cm (as an example). The aspect ratio R (i.e., the ratio R of T2 to TT) of bezel 16 is typically greater than 1 (e.g., R may be greater than or equal to 1, greater than or equal to 2, greater than or equal to 4, greater than or equal to 10, etc.).

The rim 16 need not have a uniform cross-section. For example, if desired, an upper portion of bezel 16 may have an inwardly projecting lip to help hold display 14 in place. The bottom of the bezel 16 may also have an enlarged lip (e.g., in the plane of the back surface of the device 10) if desired. In the example of fig. 1, the bezel 16 has substantially straight vertical sidewalls. This is merely illustrative. The inner and outer surfaces of the rim 16 may be curved or have any other suitable shape.

Display 14 includes conductive structures. The conductive structures may comprise an array of capacitive electrodes, conductive lines for addressing pixel elements, driver circuitry, etc. These conductive structures tend to block radio frequency signals. Therefore, it may be desirable to form part or all of the flat back surface of the device from an insulator material (e.g., glass or plastic) so that the antenna signal is not blocked. If desired, the back of the housing 12 may be formed of metal and the remainder of the device 10 may be formed of an insulator. For example, the antenna structure may be located under an insulating portion of display 14, such as a portion of display 14 that is covered with cover glass and does not contain conductive components.

The bezel 16 portion may have a notched configuration. For example, the bezel 16 may have one or more notches, such as notch 18 shown in FIG. 1. Notch 18 is located at the periphery of the housing of device 10 and display 12, and is therefore sometimes referred to as a peripheral notch. The notches 18 separate the bezel 16 (i.e., there are generally no conductive portions of the bezel 16 within the notches 18). Thus, the notch 18 will block the bezel 16 around the periphery of the device 10. With the gap 18 thus interposed in the bezel 16, electrical continuity of the bezel 16 is broken (i.e., there is an open circuit within the bezel 16 across the gap 18).

As shown in fig. 1, the gap 18 may be filled with an insulator. For example, the gap 18 may be filled with air. To help provide the device 10 with a smooth, continuous appearance, and to ensure the aesthetic appeal of the bezel 16, the gap 18 may be filled with a solid (non-air) insulator such as plastic. Bezel 16 and notches such as notch 18 (and associated plastic fill structures) may form part of one or more antennas in device 10. For example, portions of the rim 16 and notches such as notch 18 may, along with internal conductive structures, form one or more inverted-F antennas. The internal conductive structures may include printed circuit board structures, frame assemblies or other support structures, conductive traces formed on plastic support surfaces, fixtures such as screws, springs, metal strips, wires, and other suitable conductive structures.

In one particular case, the device 10 may have upper and lower antennas (as an example). The upper antenna may be formed, for example, at an area 22 at the upper end of the device 10. The lower antenna may be formed, for example, at region 20 at the lower end of device 10.

The upper antenna may be formed, for example, in part by a portion of the rim 16 adjacent the notch 18. The lower antenna may be formed in a similar manner by portions of the bezel 16 and corresponding bezel notches.

The antennas in device 10 may be used to support any communications band of interest. For example, device 10 may include a wireless communication interface for supporting local area network communications, voice and data cellular telephone communications, Global Positioning System (GPS) communications, wireless communication,Antenna structures for communications, etc. By way of example, a lower antenna at region 20 of device 10 may be used to handle voice and data communications on one or more cellular telephone bands, while an upper antenna at region 22 of device 10 may cover a first frequency band for processing Global Positioning System (GPS) signals at 1575MHz, and for processing signals at 2.4GHzAnd a second frequency band of IEEE802.11 (wireless local area network) signals as an example). The lower antenna (in this example) may be implemented with a loop antenna design and the upper antenna may be implemented with an inverted-F antenna design.

Fig. 2 shows a schematic diagram of an exemplary electronic device. The device 10 in fig. 2 may be a portable computer such as a portable tablet computer, a mobile phone with media playing capabilities, a handheld computer, a remote control, a game console, a Global Positioning System (GPS) device, a combination of these devices, or any other suitable electronic device.

As shown in fig. 2, device 10 may include storage and processing circuitry 28. The storage and processing circuitry 28 may include memory, such as hard drive memory, non-volatile memory (e.g., a solid state drive configured as flash memory or other electrically programmable read-only memory), volatile memory (e.g., static or dynamic random access memory), and so forth. Processing circuitry in storage and processing circuitry 28 may be used to control the operation of device 10. The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, and the like.

The storage and processing circuitry 28 may be used to run software on the device 10 such as internet browsing applications, Voice Over Internet Protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, and so forth. To support interaction with external equipment, the storage and processing circuitry 28 may be used to execute communication protocols. Communication protocols that may be executed by the storage and processing circuitry 28 include internet protocols, wireless local area network protocols (e.g., IEEE802.11 protocols, sometimes referred to as IEEE802.11 protocols)) Protocols for other short-range wireless communication links such asProtocols, cellular telephone protocols, and the like.

Input-output circuitry 30 may be used to allow data to be provided to device 10, allowing data to be provided from device 10 to external devices. Input and output devices 32 such as touch screens and other user input interfaces are examples of input and output circuitry 30. The input-output devices 32 may also include user input-output devices such as buttons, joysticks, click wheels, scroll wheels, touch pads, keypads, keyboards, microphones, cameras, and the like. A user may control the operation of device 10 through commands provided via these user input devices. A display may be included in device 32 as well as audio devices such as display 14 (fig. 1) and other components that may present visual information and status data. The display and audio components of the input-output device 32 may also include audio devices such as speakers and other devices for producing sound. If desired, the input and output devices 32 may include audio-visual interface devices such as jacks and other connectors for external headphones and monitors.

Wireless communications circuitry 34 may include Radio Frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low noise input amplifiers, passive RF components, one or more antennas, and other circuitry for processing RF wireless signals. Wireless signals may also be transmitted using light (e.g., using infrared communication). The wireless communication circuitry 34 may include radio-frequency transceiver circuitry for handling multiple radio-frequency communication bands. For example, circuitry 34 may include transceiver circuitry 36 and 38. Transceiver circuitry 36 may process for2.4GHz and 5GHz bands for (IEEE 802.11) communications, and for handling 2.4GHzA communication frequency band. Circuitry 34 may use cellular telephone transceiver circuitry 38 to handle wireless communications in cellular telephone bands, such as the GSM bands at 850MHz, 900MHz, 1800MHz, and 1900MHz, and the data band at 2100MHz (as an example). The wireless communication circuitry 34 may include circuitry for other short-range and long-range wireless links, if desired. For example, the wireless communication circuitry 34 may include Global Positioning System (GPS) receiver equipment, such as GPS receiver circuitry 37 for receiving GPS signals or processing other satellite positioning data at 1575MHz, radio circuitry for receiving radio and television signals, paging circuitry, and so forth. In thatAndin links and other short-range wireless links, wireless signals are typically used to transmit data over tens or hundreds of feet. In cellular telephone links and other long range links, wireless signals are typically used to transmit data over thousands of feet or miles.

The wireless communication circuit 34 may include an antenna 40. Antenna 40 may be formed using any suitable type of antenna. For example, antenna 40 may include an antenna having a resonating element formed from a loop antenna structure, a patch antenna structure, an inverted-F antenna structure, a slot antenna structure, a planar inverted-F antenna structure, a helical antenna structure, a hybrid of these designs, and so forth. Different models of antennas may be used for different frequency bands and mixed frequency bands. For example, one antenna may be used to form a local wireless link antenna and another antenna may be used to form a remote wireless link antenna.

In one suitable configuration, sometimes described herein as an example, an upper antenna in device 10 (e.g., antenna 40 in fig. 1 located in region 22 of device 10) may use an inverted-F antenna design, where some of the antennas include conductive device structures such as portions of bezel 16. The notch 18 may help define the shape and size of the portion of the bezel 16 that is part of the antenna.

Fig. 3 shows a cross-sectional side view of the illustrative apparatus 10. As shown in FIG. 3, display 14 may be mounted to the front surface of device 10 through the use of bezel 16. The housing 12 may include side walls formed by the bezel 16 and one or more back walls formed by structures, such as the structure of the planar back shell structure 42. The structure 42 may be constructed of an insulator, such as glass, ceramic, composite, plastic, or other suitable material. Snaps, clasps, screws, adhesives, and other structures may be used to mount display 14, bezel 16, and back case wall structure 42 into device 10.

Device 10 may include a printed circuit board, such as printed circuit board 46. Printed circuit board 46 and other printed circuit boards in device 10 may be formed from rigid printed circuit board material (e.g., fiberglass-filled epoxy) or flexible sheet material such as a polymer. A flexible printed circuit board ("flex circuit") may be formed, for example, from a flexible polyimide sheet.

The printed circuit board 46 may include interconnects such as interconnect 48. The interconnects 48 may be comprised of conductive traces (e.g., gold plated copper or other metal traces). A connector, such as connector 50, may be connected to interconnect 48 using solder or a conductive adhesive, as examples. Integrated circuits, discrete components such as resistors, capacitors, and inductors, and other electronic components may be mounted to the printed circuit board 46.

The antenna 40 may have an antenna feed terminal. For example, antenna 40 may have a positive antenna feed terminal, such as positive antenna feed terminal 58, and a ground antenna feed terminal, such as ground antenna feed terminal 54. In the illustrative arrangement of fig. 3, a transmission line such as a coaxial cable 52 may be coupled between an antenna feed formed by terminals 58 and 54 and transceiver circuitry in assembly 44 via connector 50 and interconnect 48. This is merely illustrative. Radio frequency antenna signals may be communicated between the antenna 40 and transceiver circuitry on the device 10 using any suitable configuration (e.g., transmission lines formed from traces on a printed circuit board, etc.).

Element 44 may include one or more integrated circuits for implementing transceiver (receiver) circuitry 37 and transceiver circuitry 36 and 38 in fig. 2. The connector 50 may be, for example, a coaxial cable connector connected to the printed circuit board 46. The cable 52 may be a coaxial cable or other transmission line. The terminal 58 may be coupled to a positive conductor (e.g., the coaxial cable center connector 56) in the transmission line 52. The terminal 54 may be connected to a ground connector within the transmission line 52 (e.g., a conductive outer braid conductor within a coaxial cable). Other means may be used to couple the transceiver in device 10 with antenna 40 if desired (e.g., using a transmission line formed on a printed circuit). The arrangement in fig. 3 is merely schematic.

Antenna 40 (i.e., the upper antenna of device 10 located in region 22 in fig. 1) may be formed using an inverted-F design. Fig. 4 shows an exemplary inverted-F antenna configuration. As shown in fig. 4, inverted-F antenna 40 may include a ground (such as ground 60) and an antenna resonating element (such as antenna resonating element 66).

Ground 60, sometimes referred to as a ground plane or ground plane element, may be formed from one or more conductive structures (e.g., planar conductive traces on printed circuit board 46, internal structural components in device 10, electronic components 44 on board 46, radio frequency shielding cans mounted on board 46, housing structures such as portions of bezel 16, etc.).

Antenna resonating element 66 may have a main resonating element arm such as arm 62, a feed leg such as leg F, and a shorting leg such as leg S1. Legs S1 and F may sometimes be referred to as arms or branches of resonating element 66. Shorting leg S1 may form a short circuit between antenna resonating element main arm 62 and ground 60. The antenna 40 may be fed by coupling radio frequency transceiver circuitry between the positive antenna feed terminal 58 on the antenna feed leg F and the ground antenna feed terminal 54.

In some device environments, inverted-F antennas of the type shown in fig. 4 may consume more space than is desirable. As shown in fig. 5, space consumption may be minimized by providing antenna 40 with one or more curved antenna resonating elements. As shown in fig. 5, antenna 40 may include a ground, such as ground 60, and an antenna resonating element, such as antenna resonating element 66. The shorting leg S1 may connect the arm 62 to ground 60. The feed leg F may connect the arm 62 to the antenna feed terminal 58. The main resonant element arm 62 may have a bend, such as bend 64.

The bend 64 may have any suitable angle (e.g., a right angle, an acute angle, an obtuse angle, etc.). In the example of fig. 5, the bend 64 has an angle of 180 ° (the bend 64 is folded in the arm 62). Due to the presence of the bend 64, the arm 62 has two parallel sections 62A and 62B.

In the example of fig. 5, the arm portion 62A and the arm portion 62B are parallel to each other, but this is merely illustrative. In general, antenna resonating element arm 62 may have different angles and different numbers of bends. Thus, there may be two or more resonant element arm segments in the arm 62, and one, two or more corresponding bends. The arm 62 may also have one or more individual branches, regions of locally increased or decreased width, or other features. These features may be used to improve the geometry of antenna 40 to suit design goals, modify the frequency response of antenna 40, and so on.

It may be desirable for antenna 40 to exhibit satisfactory performance over a variety of frequency bands. For example, it may be desirable for antenna 40 to handle a first communications band at 1575MHz (e.g., for processing GPS signals) and a second communications band at 2.4GHz (e.g., for processingAnd IEEE802.11 signals). Fig. 6 shows the structure of an exemplary antenna that may be used in device 10 to support multiple frequency band operation.

As shown in fig. 6, antenna 40 may have an inverted-F configuration in which resonating element arm 62 is itself folded back at bend 64. Due to the presence of the bend 64, the arm segments 62A and 62B are parallel to each other. Feed leg F may connect resonating element arm 62 to positive antenna feed terminal 58. The antenna 40 may be fed by using the positive antenna feed terminal 58 and the ground antenna feed terminal 54. For example, the positive conductor in the transmission line 52 may be coupled to the positive antenna feed terminal 58 and the ground conductor in the transmission line 52 may be coupled to the ground antenna feed terminal 54 (and thus to a conductive portion of the ground 60 connected to the ground antenna feed terminal 54).

Housing structure 16 may be used to form some of antennas 40. As shown in FIG. 6, the housing structure 16 may include bezel segments 16A-1 and 16A-2 along the left side of the device 10, bezel segment 16C along the right side of the device 10, bezel segment 16B along the lower side of the device 10, and bezel segments 16D-1 and 16D-2 along the upper side of the device 10.

The shorting leg S1 may be formed using the bezel segment 16A-1. Segments 16A-1 and 16A-2 may be electrically connected at node 72 (i.e., segments 16A-1 and 16A-2 may be portions of a continuous length of bezel 16). Bezel segment 16D-1 can be used to form primary resonating element arm segment 62A. Segment 62B may be formed from conductive metal traces formed on an insulating member inside housing 12 (as an example). Springs, pads, and other conductive members may be inserted at one or more locations along the length of the arm 62, if desired. The notch 18 can separate the bezel segment 16D-1 from the bezel segment 16D-2. Thus, the location of the notch 18 may define the length of 16D-1 and the resonating arm segment 62A. The length of the resonating element arm segment 62B may be defined by the size and shape of the conductive traces or other conductive structures forming segment 62B. Some or all of the bezel segments 16A-2, 16D-2, 16C, and 16B may be shorted to ground plane 60, if desired. Some or all of these segments may also be used to form additional antennas (e.g., lower antennas for device 10). The ground plane 60 may be formed from traces on a printed circuit board or may be formed from conductive structures such as those associated with input-output port connectors, shielded cans, integrated circuits, traces on a printed circuit board, housing frame members, and other conductive materials.

The presence of parallel shorting leg S2 and shorting leg S1 may help antenna 40 handle signals of multiple frequency bands. The effect of shorting leg S2, which corresponds to antenna 40 with and without leg S2, can be understood with reference to the smith chart in fig. 7. In the smith chart of fig. 7, point 74 represents a 50 ohm impedance (i.e., an impedance suitable for matching a transmission line such as transmission line 52 of fig. 3). At frequencies that deviate significantly from the point 74, the performance of the antenna may be degraded due to impedance mismatch. At the operating frequency of the antenna where the distance to point 74 is minimal, the impedance match is generally satisfactory (i.e., the antenna will resonate).

Curve 76 corresponds to the performance of antenna 40 without shorting leg S2. The low band segment LB of curve 76 is located in a first communications band of interest (e.g., the GPS band of 1575 MHZ). The high band segment HB is located in a second communication band of interest (e.g., AND)Andthe relevant 2.4GHz band).

Without shorting leg S2, low band segment LB would be located at a greater than desired distance from point 74, whereas high band segment HB is located at an acceptably short distance from point 74. To tune the impedance of antenna 40 so that both low band and high band performance are satisfactory at the same time, shorting leg S2 may be included in antenna 40. With the shorting leg S2, there is an additional shunt inductance from the arm 62 to ground 60 parallel to the shorting leg S1. In the circle of fig. 7, this additional shunt inductance shifts the position of the low band segment LB to the position occupied by the low band segment LB'. Segment LB' is acceptably close to point 74, so antenna 40 will exhibit satisfactory low band (GPS) performance when shorting leg S2 is present. The inclusion of shorting leg S2 will tend to shift the position of high band segment HB more or less, but in antenna 40 any impact on high band performance is generally minimal compared to the improved low band performance with segment LB'.

Presented in fig. 8 and 9 are graphs of how the antenna 40 works with the shorting leg S2 and without the shorting leg S2. In the graph of fig. 8, the Standing Wave Ratio (SWR) values are plotted as a function of frequency for an antenna without shorting leg S2 (i.e., antenna 40 of fig. 5). In the graph of fig. 9, the standing wave ratio is plotted as a function of frequency for an antenna having a shorting leg S2 (i.e., antenna 40 of fig. 6).

As shown in the graph of fig. 8, an antenna without shorting leg S2 may be on the second wireless communication band (i.e., at frequency f)₂In a second frequency band, such as 2.4GHzFrequency band) exhibits resonance, but over a first frequency band (i.e., at frequency f)₁A first frequency band such as the GPS frequency of 1575 MHz) has no significant resonance. Such an antenna may be used to handle wireless communications in the second frequency band.

As shown in the graph of fig. 9, an antenna having a shorting leg S2 (such as antenna 40 in fig. 6) is in a first frequency band (i.e., at frequency f)₁A first frequency band such as the GPS frequency of 1575 MHz) and a second frequency band (i.e., at frequency f)₂In a second frequency band, such as 2.4GHzFrequency band) will exhibit resonance. Because such an antenna with a frequency response as shown in fig. 9 can handle radio frequency signals in two frequency bands, such an antenna is sometimes referred to as a multi-band antenna or a dual-band antenna. The use of antennas covering more than one frequency band may avoid the need to provide multiple separate antenna structures, thereby minimizing the amount of space consumed within the electronic device 10. The antenna 40 may be configured to handle more than two frequency bands (e.g., three or more), if desired. The dual band example of fig. 9 is merely illustrative.

Fig. 10 shows an exemplary arrangement for implementing antenna 40 of fig. 6, where antenna 40 of fig. 10 may include a main antenna resonating element arm formed from resonating element arm segments 62A and 62B, as shown in fig. 10. The arm 62A may be formed from the bezel segment 16D-1. The arm 62B may be formed from a conductive trace on the insulating member 88. The member 88 may be formed of plastic, glass, ceramic, composite, other materials, or a mixture of these materials. One or more structures may be combined to form member 88. The conductive material forming the arm segment 62B on the member 88 may be formed of a metal, such as copper, gold-plated copper, or the like. The metal may be formed directly on the member 88 or may be assembled as part of a flex circuit or other portion attached to the member 88 (e.g., using an adhesive).

A conductive structure such as spring 78 may be used to electrically connect one end 82 of the conductive trace on member 88 to one end 84 of the bezel segment 16D-1. The spring 78 may be formed of metal and may be attached to one end 84 of the bezel segment 16D-1 using a weld 80. One end 86 of spring 78 (i.e., the end of spring 78 opposite the end where solder 80 is located) may press against the conductive trace on member 88 to form a conductive connection. Other connection configurations (e.g., including welding, additional solder joints, snaps, etc.) may be used if desired.

In the configuration of fig. 10, the shorting leg S2 and the feed leg F pass above or below the resonating element arm segment 62B without making a direct electrical connection with the resonating element arm segment 62B (as shown schematically in fig. 6). Legs S2 and F may be formed using screws, springs, or other suitable conductive structures. The shorting leg S1 may be formed by a portion of the bezel 16 (i.e., bezel segment 16A). Ground 60 may be formed using a printed circuit board structure, portions of bezel 16, other portions of the housing of device 10, or other suitable conductive structures, as described in connection with fig. 6.

The indentations 18 may be filled with an insulating material 82, such as plastic, ceramic, epoxy, composite, glass, other insulators, or a mixture of these materials.

According to one embodiment, an inverted-F antenna in an electronic device having an outer periphery, comprises: a resonating element arm formed at least in part by a conductive structure on an outer periphery; a feed leg connected to the resonating element arm; a ground; a shorting leg connecting one end of the resonant element arm to the ground; a first antenna feed terminal connected to the feed leg; and a second antenna feed terminal coupled to the ground.

In accordance with another embodiment, an antenna is provided, wherein the conductive structure includes a conductive bezel surrounding a periphery of the electronic device, and wherein the conductive bezel is interrupted by at least one notch.

In accordance with another embodiment, an antenna is provided, further comprising an insulating member and a conductive structure on the insulating member, wherein the resonating element is formed in part by a segment of the conductive bezel and in part by the conductive structure on the insulating member.

In accordance with another embodiment, an antenna is provided, further comprising a spring forming part of the resonating element arm.

In accordance with another embodiment, an antenna is provided wherein a spring has a first end connected to the segment of the conductive bezel and a second end connected to the conductive trace on the insulating member.

In accordance with another embodiment, an antenna is provided wherein springs are welded to the segments of the conductive bezel.

In accordance with another embodiment, an antenna is provided, further comprising an additional shorting leg connected between the resonating element arm and the ground in parallel with the shorting leg.

In accordance with another embodiment, an antenna is provided wherein the shorting leg is at least partially formed from a first section of the conductive bezel and wherein the resonating element arm is at least partially formed from a second section of the conductive bezel.

In accordance with another embodiment, an antenna is provided, further comprising an insulating member and a conductive trace on the insulating member, wherein the resonating element is formed in part by the second segment of the conductive bezel and in part by the conductive trace on the insulating member.

In accordance with another embodiment, an antenna is provided further comprising a spring connected between the second segment of the conductive bezel and the conductive trace.

According to another embodiment, there is provided an inverted F antenna in an electronic device having an outer peripheral side, including: a resonant element arm formed at least in part by a section of conductive shell structure arranged along one of the sides; a ground; and a shorting leg connecting the resonating element arm to the ground.

In accordance with another embodiment, there is provided an inverted-F antenna in which the section of the conductive housing structure includes a portion of a conductive bezel that surrounds substantially all of the peripheral side of the electronic device, the inverted-F antenna further including a feed leg connected to the resonating element arm.

In accordance with another embodiment, an inverted-F antenna is provided wherein the shorting leg is formed in part by the conductive bezel.

In accordance with another embodiment, an inverted-F antenna is provided, further comprising a second shorting leg connecting the resonating element arm to ground.

In accordance with another embodiment, an inverted-F antenna is provided wherein the resonating element arm includes at least one 180 ° bend.

In accordance with another embodiment, an inverted-F antenna is provided, further comprising an insulating member and a conductive trace on the insulating member, wherein the resonating element comprises a first portion formed by the segment of the conductive housing structure and a second portion formed by the conductive trace.

In accordance with another embodiment, an inverted-F antenna is provided, wherein the conductive housing structure includes a portion of a conductive bezel around the peripheral side of the electronic device, wherein a resonating element arm has a bend, and wherein the conductive bezel has a notch at the bend of the resonating element arm.

According to one embodiment, there is provided a handheld electronic device having four sides, comprising: a conductive bezel extending along each of the four sides, wherein the conductive bezel has at least one notch; an inverted-F antenna having an antenna resonating element formed from a segment of the conductive bezel adjacent the gap.

In accordance with another embodiment, a handheld electronic device is provided, wherein the inverted-F antenna comprises: a ground; a shorting leg connecting one end of the antenna resonating element to the ground.

In accordance with another embodiment, there is provided a handheld electronic device, further comprising: a first antenna feed terminal connected to ground; a second antenna feed terminal; a feed leg connected between the antenna resonating element and the second antenna feed terminal; and an additional shorting leg parallel to the shorting leg, wherein the additional shorting leg is connected between the antenna resonating element and the ground, wherein the shorting leg is at least partially formed by the conductive rim, and wherein the antenna resonating element arm includes a conductive structure separate from the conductive rim.

The foregoing merely illustrates the principles of the invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. The embodiments described above may be implemented alone or in any combination.

Claims (20)

1. An inverted-F antenna in an electronic device having an outer perimeter, comprising:

a resonating element arm formed at least in part by a conductive structure on an outer periphery;

a feed leg connected to the resonating element arm;

a ground plane element;

a shorting leg connecting one end of the resonating element arm to the ground plane element;

a first antenna feed terminal connected to the feed leg; and

a second antenna feed terminal coupled to the ground plane element.

2. The antenna defined in claim 1 wherein the conductive structure comprises a conductive bezel that surrounds a periphery of the electronic device and wherein the conductive bezel is interrupted by at least one notch.

3. The antenna defined in claim 2 further comprising an insulating member and a conductive trace on the insulating member, wherein the resonating element is formed in part from a segment of the conductive bezel and in part from the conductive trace on the insulating member.

4. The antenna defined in claim 3 further comprising a spring that forms part of the resonating element arm.

5. The antenna defined in claim 4 wherein the spring has a first end connected to the segment of the conductive bezel and a second end connected to the conductive trace on the insulating member.

6. The antenna defined in claim 5 wherein springs are soldered to the segments of the conductive bezel.

7. The antenna defined in claim 2 further comprising an additional shorting leg connected between the resonating element arm and the ground plane element in parallel with the shorting leg.

8. The antenna defined in claim 7 wherein the shorting leg is formed at least in part from a first section of the conductive bezel and wherein the resonating element arm is formed at least in part from a second section of the conductive bezel.

9. The antenna defined in claim 8 further comprising an insulating member and a conductive trace on the insulating member, wherein the resonating element is formed in part from the second segment of the conductive bezel and in part from the conductive trace on the insulating member.

10. The antenna defined in claim 9 further comprising a spring connected between the second segment of the conductive bezel and the conductive trace.

11. An inverted-F antenna in an electronic device having a peripheral side, comprising:

a resonant element arm formed at least in part by a section of conductive shell structure arranged along one of the sides;

a ground plane element; and

a shorting leg connecting the resonating element arm to the ground plane element.

12. The inverted-F antenna of claim 11, wherein the segment of the conductive housing structure comprises a portion of a conductive bezel that surrounds substantially all of the peripheral side of the electronic device, the inverted-F antenna further comprising a feed leg connected to the resonating element arm.

13. The inverted-F antenna of claim 12, wherein the shorting leg is formed in part by the conductive bezel.

14. The inverted-F antenna of claim 13, further comprising a second shorting leg connecting the resonating element arm to a ground plane element.

15. The inverted-F antenna of claim 14, wherein the resonating element arm comprises at least one 180 ° bend.

16. The inverted-F antenna defined in claim 11 further comprising an insulating member and a conductive trace on the insulating member, wherein the resonating element arm comprises a first portion formed from the segment of the conductive housing structure and a second portion formed from the conductive trace.

17. The inverted-F antenna defined in claim 16 wherein the conductive housing structure comprises a portion of a conductive bezel that surrounds the peripheral side of the electronic device, wherein resonant element arm has a bend, and wherein the conductive bezel has a notch at the bend of the resonant element arm.

18. A handheld electronic device having four sides, comprising:

a conductive bezel extending along each of the four sides, wherein the conductive bezel has at least one notch; and

an inverted-F antenna having an antenna resonating element formed from a segment of the conductive bezel adjacent the notch.

19. The handheld electronic device defined in claim 18 wherein the inverted-F antenna comprises:

a ground plane element;

one end of the antenna resonating element is connected to the shorting leg of the ground plane element.

20. The handheld electronic device defined in claim 19 further comprising:

a first antenna feed terminal connected to the ground plane element;

a second antenna feed terminal;

a feed leg connected between the antenna resonating element and the second antenna feed terminal; and

an additional shorting leg parallel to the shorting leg, wherein the additional shorting leg is connected between the antenna resonating element and the ground plane element, wherein the shorting leg is at least partially formed by the conductive bezel, and wherein the antenna resonating element comprises a conductive structure separate from the conductive bezel.