US20080194288A1 - Integrated circuit including packet network transceivers and fm receiver with fm antenna control - Google Patents

Abstract

An integrated circuit and/or device is provided that supports wireless communications. The integrated circuit includes wireless communication circuitry, frequency modulated (FM) receiver circuitry, and FM antenna control circuitry. The communication circuitry is coupled to convert an inbound radio frequency (RF) signal into an inbound data signal and to convert an outbound data signal into an outbound RF signal. The integrated circuit also includes FM receiver circuitry that is coupled to convert an inbound continuous wavelength signal into an inbound FM data signal. FM antenna control circuitry is coupled to the FM receiver circuitry for producing control signals to control a center frequency of a gain profile of an FM antenna.

Description

CROSS REFERENCE TO RELATED APPLICATIONS
• This application is a continuation-in-part of U.S. application Ser. No. ______, (Attorney Docket BP6124), filed May 16, 2007, which claims priority to U.S. Provisional Application Ser. No. 60/889,528 entitled “Mobile Phone with an Antenna Structure having Improved Performance,” filed Feb. 12, 2007, all of which are hereby incorporated herein by reference in their entirety for all purposes.
SPECIFICATION
• 1. Technical Field
• The present invention relates to wireless communications and, more particularly, signal reception and transmission in mobile wireless communication systems.
• 2. Related Art
• Communication systems are known to support wireless and wire lined communications between wireless and/or wire lined communication devices. Such communication systems range from national and/or international cellular telephone systems to the Internet to point-to-point in-home wireless networks. Each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, wireless communication systems may operate in accordance with one or more standards, including, but not limited to, IEEE 802.11, Bluetooth, advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), and/or variations thereof.
• Depending on the type of wireless communication system, a wireless communication device, such as a mobile telephone, two-way radio, personal digital assistant (PDA), personal computer (PC), laptop computer, home entertainment equipment, et cetera, communicates directly or indirectly with other wireless communication devices. For direct communications (also known as point-to-point communications), the participating wireless communication devices tune their receivers and transmitters to the same channel or channels (for example, one of a plurality of radio frequency (RF) carriers of the wireless communication system) and communicate over that channel(s). For indirect wireless communications, each wireless communication device communicates directly with an associated base station (for example, for cellular services) and/or an associated access point (for example, for an in-home or in-building wireless network) via an assigned channel. To complete a communication connection between the wireless communication devices, the associated base stations and/or associated access points communicate with each other directly, via a system controller, via a public switch telephone network (PSTN), via the Internet, and/or via some other wide area network.
• Each wireless communication device includes a built-in radio transceiver (that is, a receiver and a transmitter) or is coupled to an associated radio transceiver (for example, a station for in-home and/or in-building wireless communication networks, radio frequency (RF) modem, et cetera). As is known, the transmitter includes a data modulation stage, one or more intermediate frequency stages, and a power amplifier stage. The data modulation stage converts raw data into baseband signals in accordance with the particular wireless communication standard. The one or more intermediate frequency stages mix the baseband signals with one or more local oscillations to produce RF signals. The power amplifier stage amplifies the RF signals prior to transmission via an antenna.
• An antenna is an essential element for a wireless communication device. The antenna provides a wireless interface for the wireless communication device, which may be a radio, mobile phone, pager, station (for wireless local area network, wireless internet, et cetera). The particular type of wireless communication system, which prescribes the transmission frequencies, reception frequencies and power levels, dictates the performance requirements for the antenna.
• Because most wireless communication devices are handheld or portable devices, each component including these devices must be small, efficient, economical and lightweight—generally, provided in forms of systems on chips or other integrated circuits. The antenna is no exception—it too must be small, efficient, economical and lightweight. To achieve these requirements, many antennas have been developed having various structures including monopole, dipole, et cetera.
• The diminutive size of the antennas, however, leave them more susceptible to environmental changes that correspondingly affect the ability of an antenna to reliably receive and/or transmit signals. For example, mobile phones can be readily held within the grasp of a user, or placed within a pocket, et cetera. When environmental conditions change, the impedance and consequently the ability of the antenna are adversely affected, reducing the signal-to-noise performance of the antenna.
• Although favorable environmental conditions may return, a user becomes frustrated by the inconsistency of the service for their mobile phone or device. Also, the compactness of mobile wireless devices can cause E-M interference between other device components, further degrading antenna performance. Accordingly, various types of antennas and corresponding shapes provide adequate antenna performance. Nevertheless, they become becoming increasingly sensitive to environmental changes and interference from other device components. Therefore, a need exists for miniaturized integrated circuit systems to be able to control antenna impedances to improve the performance of increasingly sensitive antennae.
SUMMARY
• The present invention is directed to apparatus and methods of operation that are further described in the following Brief Description of the Drawings, the Detailed Description of the Drawings, and the claims. Other features and advantages of the present invention will become apparent from the following detailed description of the drawings made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiment is considered with the following drawings, in which:
• FIG. 1 is a functional block diagram illustrating a communication system that includes a plurality of base stations or access points (APs), a plurality of wireless communication devices and a network hardware component;
• FIG. 2 is a schematic block diagram illustrating a wireless communication device architecture including an FM transceiver and an FM antenna tuning module according to an embodiment of the present invention;
• FIG. 3 is an illustration for a center frequency of a gain profile of an FM antenna;
• FIG. 4 is a schematic block diagram illustrating a wireless communication device architecture including an FM transceiver an FM antenna tuning module coupled with a tuning circuit according to an embodiment of the present invention;
• FIG. 5 is a schematic block diagram further illustrating an integrated circuit that supports wireless communications according to an embodiment of the present invention;
• FIG. 6 is a schematic block diagram of another integrated circuit that supports wireless communications according to an embodiment of the present invention;
• FIG. 7 is an exploded view of a mobile phone with a brick configuration that includes an antenna structure according to an embodiment of the present invention;
• FIG. 8 is an exploded view of a mobile phone with a clamshell configuration that includes an antenna structure according to an embodiment of the present invention;
• FIG. 9 is a cross-sectional diagram of an antenna structure including a printed FM antenna in a first orientation according to an embodiment of the present invention;
• FIG. 10 is a cross-sectional diagram of an antenna structure including a printed FM antenna in a second orientation according to another embodiment of the invention;
• FIG. 11 is an exploded view of another antenna structure including a dielectric spacer according to a further embodiment of the present invention; and
• FIG. 12 is a cross-sectional diagram of the antenna structure ofFIG. 11.
DETAILED DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a functional block diagram illustrating a communication system that includes circuit devices and network elements and operation thereof. More specifically, a plurality ofnetwork service areas04,06 and08 are a part of anetwork10.Network10 includes a plurality of base stations or access points (APs)12-16, a plurality of wireless communication devices18-32 and anetwork hardware component34. The wireless communication devices18-32 may belaptop computers18 and26, personaldigital assistants20 and30,personal computers24 and32 and/ormobile telephones22 and28.
• The base stations or APs12-16 are operably coupled to thenetwork hardware component34 via local area network (LAN)connections36,38 and40. Thenetwork hardware component34, which may be a router, switch, bridge, modem, system controller, et cetera, provides a widearea network connection42 for thecommunication system10 to an external network element. Each of the base stations or access points12-16 has an associated antenna or antenna array to communicate with the wireless communication devices in its area. Typically, the wireless communication devices18-32 register with the particular base station or access points12-16 to receive services from thecommunication system10. For direct connections (that is, point-to-point communications), wireless communication devices communicate directly via an allocated channel.
• Some or all of the wireless communication devices18-32 may include a FM transceiver to receive and/or transmit continuous waveform signals in the FM frequency broadcast band, which in the United States is 87.9 to 107.9 MHz. It can be appreciated, however, that FM may be transmitted on any frequency. In the present example,wireless communication devices22,24,28,30, and32 includeFM transceivers23,25,31,33, and35, respectively. In this manner, the wireless communication devices may receive and/or transmit media content via FM frequency transmission techniques.
• In addition to media content (such as audio, video, et cetera), a wireless communication device may receive and/or transmit additional information such as Radio Data System (“RDS”) information, which provides digital information regarding FM radio broadcasts. This information can include items such as time, track/artist information, station identification, et cetera.
• FM broadcast stations54 and56 transmit media content over continuous waveforms in the FM band, in which the FM transceivers23-33 receive via their respective FM antennas. The FM transceivers then process the signals for playback of the media content to a user device. Also, the wireless communication devices may transmit FM signals as a local broadcast to nearby audio devices having FM receivers, such as personal stereos, automobile FM radios, et cetera.
• The small wireless devices include correspondingly-sized FM antennas having an antenna structure, which improves the antenna performance across non-ideal environmental conditions for the small wireless device. In general, a human body proximate to an FM antenna affects the impedance of the FM antenna (such as the wireless device being clasped in a user's hand, stored in a pocket, notebook, et cetera). As a person moves either closer to or further away from an antenna, the change in the relative position of the person proximate to the antenna causes the impedance of the antenna to change. A human body also absorbs the radio frequency waves, affecting the electric field and the magnetic field of the RF wave. Because the FM antennas are reduced to fit within a smaller wireless device, the antenna impedances become more sensitive to these varying environmental conditions.
• As a result, the varying antenna impedances resulting from the non-ideal environmental conditions affect the signal processing and media content playback to a user. For example, when reception conditions are less than ideal (that is, the signal-to-noise ratio worsens), a stereo FM broadcast playback is in mono, or the FM signal may be dropped altogether. With ever varying environmental conditions, the varying and/or inconsistent playback frustrates users. FM antenna control circuitry and antenna structure are discussed in greater detail with reference toFIGS. 2 through 12.
• FIG. 2 is a schematic block diagram illustrating a wireless communication device22-32. As illustrated, wireless communication device22-32 includes adigital processing module54, amemory56, user interface(s)52, transceivers58-66, an FMantenna control circuitry68, aFM antenna70, andantenna switch72. Thedigital processing module54 andmemory56 execute instructions and perform corresponding communication functions in accordance with a particular mobile and/or cellular phone standard.
• User interface(s)52 allows data to be received from and provides connectivity to an output device such as a display, monitor, speakers, microphone, et cetera, such that the received data may be displayed and/or presented. Thedigital processing module54 may also receive the outbound data from an input device such as a keyboard, keypad, microphone, et cetera, via the user interface(s)52 or generate the data itself. The user interface providesoutbound data76 to thedigital processing module54 for transmission via one of the transceivers58-66. The user interface also receivesinbound data74 destined for a user.
• The wireless communication device22-32 includes several transceivers (that is, receiver and transmitter) for accommodating different communication and/or data sessions. The wireless communication device22-32 includes a cellular transceiver58 (for example, Personal Communication System (PCS), Global System for Mobile Communications (GSM), Wideband CDMA, et cetera), a Wireless Wide Area Network (WWAN) transceiver60 (for example, WiMAX, HSDPA, et cetera), a Wireless LAN (WLAN) transceiver62 (for example, IEEE 802.11), a Wireless Personal Area Network (WPAN) transceiver64 (for example, Bluetooth, IEEE 802.15, et cetera), and aFM transceiver66.
• The transmitter portion of a transceiver generally includes a data modulation stage, one or more intermediate frequency stages, and a power amplifier stage. The data modulation stage converts raw data into baseband signals in accordance with the particular wireless communication standards specification. The one or more intermediate frequency stages mix the baseband signals with one or more local oscillations to produce RF signals. The power amplifier stage amplifies the RF signals prior to transmission via an antenna.
• A transceiver's receiver portion generally includes a low noise amplifier (LNA) stage, one or more intermediate frequency stages, and a data demodulation stage. The LNA stage amplifies the received RF signals for providing a stronger signal for subsequent processing. The one or more intermediate frequency stages mix the RF signals with one or more local oscillations to produce baseband signals, in accordance with the particular wireless communication standards specification. In other transceiver configurations, a received FM signal may be converted directly to baseband signals. The data demodulation stage operates to convert the baseband signals into raw data.
• The transceivers58-64 receive and transmit RF signals via theantenna switch72, which operates to couple the receivers to theantenna86 in a receive mode, and to couple the transmitters in a transmit mode. Theantenna switch72 provides a many-to-one access to theantenna86 for providing efficient use of antenna resources. Examples of antenna switches are discussed in further detail in U.S. Pat. No. 7,079,816, entitled “On Chip Diversity Antenna Switch,” issued Jul. 18, 2006, which is hereby incorporated herein by reference.
• TheFM transceiver66 receives continuous waveform signals89 from an FM transmitter, such asFM broadcast stations54 and56 (seeFIG. 1), via theFM antenna70. Also, theFM transceiver66 may transmit acontinuous waveform signal89 in the FM band to a local receiver (such as a personal stereo, automobile FM radio, et cetera).
• An FMantenna tuning module68, including lumped tuningelements69, operates to adjust the impedance match with theFM antenna70 with an impedance adjustment value71. In general, the smaller the “footprint” of an FM antenna, the more vulnerable its performance is due to its positioning within a wireless communication device with respect to other components, and the more sensitive it is to changes in its operational environment that adversely affect the tuning of the antenna70 (such as by the varying proximity of a user to the wireless communication device).
• TheFM antenna70 may be provided under a variety of configurations, such as a monopole antenna, a dipole antenna (for example, such as the dipole antenna depicted in U.S. Pat. No. 7,034,770, entitled “Printed Dipole Antenna,” issued Apr. 25, 2006, which is hereby incorporated herein by reference), an eccentric spiral antenna (for example, such as the eccentric spiral antenna depicted in U.S. Pat. No. 6,947,010, entitled “Eccentric Spiral Antenna,” issued Apr. 4, 2000, which is hereby incorporated herein by reference), a fractal element antenna, et cetera. Each configuration may have different design considerations.
• As an example, a monopole antenna may have improved performance over a dipole antenna structure due to the lower ohmic loss of the antenna traces (that is, less antenna traces can be used with a monopole structure). In general, a lower ohmic loss provides theFM antenna70 with higher antenna efficiency.
• The monopole structure relies on the existing ground of themobile phone22 to generate an image of the “missing” portion (that is, the “dipole” portion for the monopole antenna). Because the wireless device may not have a perfect ground available for attachment of a monopole antenna structure, the impedance matching may be unpredictable. The overall performance of a monopole antenna, however, may improve due to the lower ohmic loss of theantenna trace218 with respect to small antenna “footprints”.
• Lower ohmic loss for an antenna may also be recognized by operating an antenna at a higher resonant frequency, f_C. For example, theFM antenna70 has a higher resonant frequency (such as two-to-three times higher) than the intended operational frequency (in the present example, the FM frequency band). The higher resonant frequency permits the electrical length of the antenna to be reduced, and correspondingly, the amount of space allocated for the antenna trace. That is, a shorter electrical length has fewer trace windings that can have larger trace surfaces in a given antenna area—the result is a lower ohmic loss. In operation with theFM transceiver66, the receiver reduces the resonant frequency of theFM antenna70 to the intended frequency resonance using discrete (or lumped) low-loss antenna matching components, such as the lumpedtuning elements69.
• A trade off, however, exists between the highest resonant frequency to which the antenna is tuned versus the amount of impedance matching (via the FM antenna control circuitry68) to bring the resonant frequency within the desired operational frequency. For instance, when the antenna resonates at a very high frequency, the required amount of impedance matching can be excessive, consequently producing excessive antenna loss. In other words, the advantage of having a lower ohmic loss and higher antenna efficiency is lost. On the other hand, when the antenna resonates substantially close to the desired resonant frequency, fewer matching components would be needed; however, the resulting ohmic loss of the resulting FM antenna trace would be comparable or larger than the radiation resistance for theFM antenna70
• Regardless of the antenna configuration deployed, theFM antenna70 has a center frequency and a gain profile. The FMantenna control circuitry68 operates to center theFM antenna70 within the desired operational frequency. The FMantenna control circuitry68, based upon a signal strength indication of a receivedcontinuous wavelength signal89, provides an adjustment control signal to the lumpedtuning elements69. The lumpedtuning elements69 correspondingly varies the impedance (and the resonance frequency) of theFM antenna70 via an impedance adjustment value71.
• The lumpedtuning elements69 include voltage-controlled variable impedance devices (such as varactors or varicap diodes) to produce the impedance adjustment value71. That is, by adjusting the impedance value through the lumpedtuning elements69, the FMantenna control circuitry68 tunes theFM antenna70 to the operational conditions of the wireless communication device22-32.
• The FMantenna control circuitry68 and the lumpedtuning elements69 may be on a single integrated circuit or a plurality of integrated circuits. Also, the FM antenna tuning module and the lumpedtuning elements69 may be implemented as part of a system on a chip. Examples of other implementations are discussed in detail with reference toFIGS. 4 through 6. Also, antenna structures are discussed in further detail with reference toFIGS. 7 through 12.
• Thedigital processing module54, in combination with operational instructions stored inmemory56, executes digital receiver and digital transmitter functions. Thedigital processing module54 may be implemented using a shared processing device, individual processing devices, or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions.
• Memory56 may be a single memory device or a plurality of memory devices. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, and/or any device that stores digital information. Note that whendigital processing module54 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory storing the corresponding operational instructions is embedded with the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry.Memory56 stores, anddigital processing module54 executes, operational instructions corresponding to at least some of the functions illustrated and/or described herein.
• In operation, thedigital processing module54 processesoutbound data76 in accordance with a particular wireless communication standard (for example, IEEE 802.11a, IEEE 802.11b, Bluetooth, IEEE 802.16, et cetera) to produce the appropriate digital transmission formatted data for a present communication session, which includescellular data59,WLAN data61,WWAN data65, and/orFM signal data67. This data will be a digital baseband signal or a digital low IF signal, where the low IF typically will be in the frequency range of one hundred kilohertz to a few megahertz.
• Each respective transceiver58-66 converts the digital data from the digital domain to the analog domain. Though theantenna86 is schematically depicted as external to the body of the radio, commercial versions of the wireless communication device generally incorporate the antenna element and structures within the body of the device. Also, the wireless communication device may also include additional antennas for standards specific applications, such as those for Bluetooth applications, et cetera.
• As one of average skill in the art will appreciate, the wireless communication device ofFIG. 2 may be implemented using one or more integrated circuits. For example, thedigital processing module54 andmemory56 may be implemented on a second integrated circuit, and the remaining components of the wireless communication device22-32,less antenna86, may be implemented on a third integrated circuit. As an alternate example, the wireless communication device22-32 may be implemented on a single integrated circuit.
• FIG. 3 is an illustration for a center, or resonant, frequency f_Cof a gain profile of an FM antenna with respect to FM signal reception, which is represented as a receivedsignal strength93. In this example, the center frequency f_Cis “off-tuned” by a value “x.” That is, the antenna is not centered with respect to the local peak of the FM signal. Unless the antenna tuning is corrected, the signal data may be distorted when processed for playback to a user (such as with static, mono playback, et cetera), or additional power resources may be needed to correct the distortion.
• The magnitude in which the center frequency is “off-tuned” corresponds, in part, to the changing operational environment. That is, the impedance changes affect the antenna center f_C, such as impedance changes the varying proximity of a user to the wireless communication device). The FM antenna control circuitry provides control signals to produce an impedance adjustment value71 to correct the tuning for the antenna. The control signals are discussed in detail with reference toFIGS. 4 through 6.
• Although the impedance adjustment value71 is shown to center the antenna center frequency f_Cwith the received signal strength, the FMantenna control circuitry68 may also provide control signals that provide a tuning offset as discussed to take advantage of smoother amplifier characteristics across a greater bandwidth.
• FIG. 4 is a schematic block diagram illustrating a wireless communication device22-32 that includes a distributed embodiment of the FMantenna control circuitry68 and the lumpedtuning elements69,
• As illustrated, the wireless communication device22-32 includes adigital processing module54 and amemory56. Thedigital processing module54 andmemory56 execute instructions and perform corresponding communication functions in accordance with a particular mobile and/or cellular phone standard. To the extent that like components and/or elements have been earlier described of the wireless communication device22-32, the description will not be repeated here with respect toFIG. 3.
• The wireless communication device22-32 includesantenna switch75 andantenna switch77.Antenna switch75 services the cellular Tx/Rx signal81 and the WWAN Tx/Rx signal83 for transmission and/or reception modes over theantenna86.Antenna switch77 services the WLAN Tx/Rx signal85 and WPAN Tx/Rx signal87 for transmission and/or reception modes over theantenna86. TheFM transceiver66 receives and/or transmits acontinuous wavelength signal89 via theFM antenna70.
• Multiple antenna switches75 and77 permit each of the antenna switches to accommodate the characteristics of similar communications modes. Examples of characteristics may include similar frequency bands, similar data rates, et cetera. For example, an antenna switch may service cellular frequency bands (such as for AMPS, IS-95 (CDMA), IS-136 (D-AMPS), GSM, operating in the 824-849 MHz, 869-894 MHz, 896-901 MHz, and 935-940 MHz frequency bands), and another antenna switch may service Personal Communication Service (“PCS”) frequency bands (such as for GSM, IS-95 (CDMA), IS-136 (D-AMPS), operating in the 1850-1910 MHz and 1930-1990 MHz frequency bands). A further antenna switch may service high-data rate communications (such as 2.4 GHz).
• TheFM transceiver66 receives from theFM antenna70 thecontinuous wavelength signal89 via the printedFM antenna70. The FMantenna control circuitry68 receives a signal strength indication (SSI) from theFM transceiver66. Also, theFM transceiver66 may provide the received FM signal to the FMantenna control circuitry68, in which signal strength or other signal characteristics may be evaluated to generate the control signals73. When the SSI falls outside a permissible signal strength level, the lumpedtuning elements69 provide an impedance adjustment value71 to the printed FM antenna based upon the control signals73 from the FMantenna control circuitry68.
• The lumpedtuning elements69 are illustrated as provided on a separate IC with respect to theFM transceiver66 and the FMantenna control circuitry68. In this manner, differing fabrication processes may be used to implement the voltage-controlled variable impedance devices of the lumpedtuning elements69 and with processes to implement other components of the wireless communication device22-32. That is, in some instances, a reduction in fabrication cost and complexity may be realized. Also, wireless communication devices may have an impedance bank accessible to other components within the device to permit shared access to those components (for example, for clock adjustment, et cetera). By adjusting the impedance value of the lumpedtuning elements69, the FMantenna control circuitry68 tunes theFM antenna70 to an impedance of the communications device22-32.
• FIG. 5 is a schematic block diagram of anintegrated circuit270 that supports wireless communications and includes FM receiver capability. Theintegrated circuit270 includesFM receiver circuitry66 and FMantenna control circuitry68. For support of wireless communications, theintegrated circuit270 also includeswireless communication circuitry57 withtransceivers58 through64 (see, e.g.,FIG. 3).
• The FMantenna control circuit68 produces control signals73 to control a center frequency of a gain profile of an FM antenna, such as FM antenna70 (seeFIG. 3). The external lumpedelement tuning array69 includes aswitch module326 and lumped tuningelements28. Theswitch module326 includes a plurality of switches S₀through S_Zthat are coupled to the lumped tuningelements328 that includes a plurality of tuning elements C₀through C_Z, which may be voltage-controlled variable impedance devices (such as varactors, varicap diodes, et cetera). The plurality of switches S₀through S_Zoperate to alter the impedance adjustment value71 via the lumped tuningelements328.
• The FM receiver circuitry receives thecontinuous wavelength signal89 and provides asignal value90 to the FMantenna control circuitry68. TheFM receiver circuitry66 also provides a FM data signal67 to thedigital processing module54.
• The FMantenna control circuitry68, based upon characteristics of the signal value90 (such as a received signal strength indication), produces control signals73 to control a center frequency of a gain profile of an FM antenna. In operation, the control signals73 control the plurality of switches S₀through S_Zof the external lumpedelement tuning array69. In turn, theswitch module326 controls the lumped elements C₀through C_Zof the lumped tuningelements328 to produce an impedance adjustment value71. In this manner, the control signals73 serve to change an impedance of the external lumpedelement tuning array69.
• Notably, the FMantenna control circuitry68 provides for rapid adjustment of the impedance adjustment value71 and correspondingly, rapid tuning of an FM antenna to accommodate changing operational conditions to the wireless communication device22-32 (seeFIG. 1).
• FIG. 6 is a schematic block diagram of anotherintegrated circuit280 that supports wireless communications and includes FM receiver capability. Theintegrated circuit270 includesFM receiver circuitry66 and FMantenna control circuitry68. The FMantenna control circuitry68 further includes aswitch module346 with a plurality of switches S₀through S_Z. For support of wireless communications, theintegrated circuit270 also includeswireless communication circuitry57 withtransceivers58 through64 (see, e.g.,FIG. 3).
• The FM receiver circuitry receives thecontinuous wavelength signal89 and provides asignal value90 to the FMantenna control circuitry68. TheFM receiver circuitry66 also provides a FM data signal67 to the digital processing module54 (FIG. 3).
• The FMantenna control circuit68, via the plurality of switches S₀through S_Zof theswitch module346, produces control signals73 to the external lumped tuningelements348. The external lumped tuningelements348 include a plurality of tuning elements C₀through C_Z, which may be voltage-controlled variable impedance devices (such as varactors, varicap diodes, et cetera).
• The FMantenna control circuitry68, based upon characteristics of the signal value90 (such as a received signal strength indication), produces control signals73 to control a center frequency of a gain profile of an FM antenna. In operation, the FMantenna control circuitry68 produces the control signals73 from the plurality of switches S₀through S_Zto the external lumped tuningelements348, to “pull” the resonant frequency f_CofFM antenna70, by changing the impedance value provided by the impedance adjustment value71 with the lumped elements C₀through C_Z. The impedance adjustment value71 provided to an FM antenna then pulls the center frequency of the gain profile of the antenna to improve reception of an FM signal.
• Notably, the FMantenna control circuitry68 provides for rapid adjustment of the impedance adjustment value71 and correspondingly, rapid tuning of an FM antenna to accommodate changing operational conditions to the wireless communication device22-32 (seeFIG. 1).
• FIG. 7 is an exploded view of amobile phone22 having anantenna structure200. Themobile phone22 has a structure sometimes referred to as a “brick.” Themobile phone22 includes acase face cover202, a caseback cover222, and abattery cover228. The case facecover202 includes a display204, a function keypad206, and anumeric keypad208. The case facecover202 receives a printedcircuit board210 having integratedcircuits212, which include transceivers58-66 (such as that discussed with reference toFIGS. 2 and 3) that is coupled to aFM antenna70 of theantenna structure200.
• Further, the printedcircuit board210 may include lumped tuning components to initially match the impedance of themobile phone22 with theFM antenna70. The caseback cover222 includes afirst side219 and asecond side221. Thesecond side221 defines a slopedportion223 to receive thebattery cover228.
• Themobile phone22 supports different forms of communication and information and/or media content. For example, in addition to supporting voice calls, themobile phone22 can also send and receive data, send text messages via a Short Messaging Service (“SMS”), access Wireless Application Protocol (“WAP”) services, provide Internet access through data technologies such as General Packet Radio Service (“GPRS”), sending and receiving pictures with built-in digital cameras, video and sound recording, et cetera. Additionally, local features may be available with themobile phone22 such as alarms, volume control, user defined and downloadable ring tones and logos, interchangeable covers, et cetera.
• Theantenna structure200 includes theFM antenna70, a conductive material forming aground plane224, and thebattery226. TheFM antenna70 includes anantenna trace218, and an input/output connection216. TheFM antenna70 has a planar structure that is less than a planar area of thebattery cover228, and is positioned adjacent the inside of thebattery cover228. TheFM antenna70 may have a variety of configurations that are designed according to varying criteria, as discussed with respect toFIG. 2.
• Also, theFM antenna70 may be implemented on one or more printed circuit board layers and/or one or more integrated circuit layers. The coupling of the transceiver circuitry of theintegrated circuits212 with theFM antenna70 may be direct or indirect and positioned on theFM antenna70 to achieve a desired load impedance. For example, the input/output connection216 may be a coaxial probe, a printed microstrip, a waveguide, and a coplanar transmission line, et cetera.
• Abattery226 has a planar structure and is positioned adjacent a second side of theground plane224, such that the planar structure of theantenna70 and of thebattery226 are substantially parallel. Theground plane224, which is positioned between thebattery226 and theFM antenna70, operates to improve a signal-to-noise performance of theFM antenna70. Thebattery226 may have a conductive outer layer that provides theground plane224 to theFM antenna70. Thebattery cover228, caseback cover222, and thecase face cover202 couple to provide the electrical and physical connectivity for operation of themobile phone22.
• FIG. 8 is an exploded view of amobile phone28 having anantenna structure200. Themobile phone28 has a structure sometimes referred to as a “clamshell” structure. Themobile phone28 supports different forms of communication and media information content. For example, in addition to supporting voice calls, themobile phone28 can also send and receive data, send text messages via a Short Messaging Service (“SMS”), access Wireless Application Protocol (“WAP”) services, provide Internet access through data technologies such as General Packet Radio Service (“GPRS”), sending and receiving pictures with built-in digital cameras, video and sound recording, et cetera. Additionally, local features may be available with themobile phone28 such as alarms, volume control, user defined and downloadable ring tones and logos, interchangeable covers, et cetera.
• Themobile phone28 includes a first portion242 and asecond portion250. The first portion242 includes akeypad244, afunction keypad246, and acase face cover254. The first portion242 also receives aFM antenna70, and abattery226, each of which being separated by aground plane224. Thebattery226,ground plane224, and theFM antenna70 may be formed as a unit with theback cover229. Thesecond portion250 of themobile phone28 includes adisplay248 for relaying call status and other information that may be retrieved and presented to the user. The first portion242 and thesecond portion250 fold along ahinge portion251 to a substantially parallel position when placed in a closed position.
• Themobile phone28, via the first portion242, receives a printedcircuit board210 having integratedcircuits212, which include transceiver circuitry58-66 (such as that discussed with reference toFIGS. 2 and 3). The FM transceiver66 (seeFIGS. 2 and 3) is coupled to theFM antenna70.
• The first portion242 of the clamshell structure provides a smaller footprint space and/or area for theFM antenna70. Accordingly, the performance of the printed FM antenna is more readily influenced by changes in its operational environment by impedance changes caused by a user and/or other objects. In this regard, theground plane224 serves to mitigate these influences and to further improve the performance of the printed FM antenna with respect to signal reception. Also, the printed circuit board may include lumped tuning components, which compensate for impedances introduced by the mobile phone components, initially tuning theFM antenna70 to the wireless communication device22-32.
• TheFM antenna70 includes anantenna trace252, and an input/output connection258. TheFM antenna70 has a planar structure that is less than a planar area of the first portion242 of thephone28, and is positioned adjacent theground plane224. TheFM antenna70 may be implemented on one or more printed circuit board layers and/or one or more integrated circuit layers. The coupling of the transceiver circuitry of the integrated circuits with theFM antenna70 may be direct or indirect, and positioned on theFM antenna70 to achieve a desired load impedance. For example, the input/output connection216 may be a coaxial probe, a printed microstrip, a waveguide, and a coplanar transmission line, et cetera.
• TheFM antenna70 may be provided under a variety of configurations depending upon the desired operational characteristics. Examples of the varying configurations are discussed in detail with respect toFIG. 2.
• Thebattery226 has a planar structure that is positioned adjacent a second side of theground plane224, such that the planar structure of theFM antenna70 and of thebattery226 are substantially parallel to each other in a spaced apart relation to improve the performance of theFM antenna70. Thebattery226,ground plane224,FM antenna70, andback cover229 may be integrated into a module that detachably couples with the first portion242 to provide the electrical and physical connectivity for operation of themobile phone28. Further, theground plane224 may be formed as a conductive layer to thebattery226.
• FIG. 9 is a cross-sectional diagram of theantenna structure200. Theantenna structure200 includes theFM antenna70 and thebattery226 with theground plane224 in a layered relation. Theantenna trace218 is electrically insulated from theground plane224 by aprotective layer225. TheFM antenna70 has a planar structure that is less than a planar area defined by the outer periphery of the mobilephone battery cover228, and is positioned such that theantenna substrate219 is adjacent the inner side of thebattery cover228. Theantenna trace218 is oriented towards theground plane224.
• Theantenna substrate219 may be formed with the battery cover288, and further may be coupled to, or form a portion of, the inner surface of thebattery cover228. Theprotective layer225 and theantenna substrate219 are made of a dielectric material that provides electrical insulation between mobile phone components while supporting electrostatic fields. Further, the dielectric material has a dielectric constant sufficient to concentrate electrostatic lines of flux while dissipating minimal energy in the form of heat. Examples of materials include air, polyethylene, polystyrene, et cetera. The planar structure of theFM antenna70, theground plane224, and the planar surface of thebattery226 are substantially parallel to each other. The sandwiched structure provides improved FM signal reception for theFM antenna70.
• FIG. 10 is a cross-sectional diagram of theantenna structure239. Theantenna structure239 illustrates another sandwich structure that may be used in themobile phones22 and/or28. Theantenna structure200 includes theFM antenna70 and thebattery226 with theground plane224 in a layered relation. Theantenna trace218 is electrically insulated and/or mechanically protected by aprotective layer225. TheFM antenna70 has a planar structure that is less than a planar area defined by the outer periphery of the mobilephone battery cover228, and is positioned such that theantenna substrate219 is adjacent theground plane224. Theantenna trace218 is adjacent the inner surface of thebattery cover228. Accordingly, the planar structure of theFM antenna70, theground plane224, and the planar surface of thebattery226 are substantially parallel to each other. The sandwiched structure provides improved FM signal performance for theFM antenna70.
• FIG. 11 is an exploded view of afurther antenna structure230 implementing adielectric spacer257. Theantenna structure230 may be used in the brick structure of themobile phone28 and/or the clamshell structure of themobile phone28, as well as other suitable wireless device structures.
• Theantenna structure230 includes theFM antenna70 and thebattery226 in a spaced-apart relation via adielectric spacer257. Thedielectric spacer257 includes a first dielectric spacer portion260 and a seconddielectric spacer portion262. Thedielectric spacer257 also includesweb portions261 that space the first anddielectric spacer portion260 and262 in a fixed relation, providing afirst side263 and asecond side265. Thedielectric spacer257 provides further separation between thebattery226 and theFM antenna70, which services to improve the E-M flux characteristics of the printed FM antenna, and improves the performance of theFM antenna70.
• Thedielectric spacer257 has different dielectric constants that are attributed to the components of thedielectric spacer257 and thecavity259 defined therein, which may be “filled” with air from the surrounding environment. Also, thedielectric space257 may be formed of a similar material throughout, or formed with multiple materials with different dielectric properties.
• In this manner, thedielectric spacer257 provides electrical insulation between theFM antenna70 and mobile phone components, while also supporting electrostatic fields. In general, the area of thedielectric spacer257 substantially corresponds to the surface area of theFM antenna70; however, dielectric spacers with smaller surface areas may also be used while the desired improvement to the performance of the printed antenna256 is realized.
• TheFM antenna70 has a planar structure less than a planar area defined by the outer periphery of thebattery cover228, and is positioned adjacent the inner surface of the mobilephone battery cover228. Thebattery226 has a planar surface positioned adjacent theground plane224, which may be a conductive outer layer of thebattery226. The conductive outer layer of thebattery226 may partially encase thebattery226 such that theground plane224 is positioned between thebattery226 and theFM antenna70. The sandwichedantenna structure230 provides improved FM signal performance for theFM antenna70.
• FIG. 12 is a cross-sectional diagram of theantenna structure230 ofFIG. 8 with thedielectric spacer257 and agap231 between theantenna structure230 and thebattery cover228.
• Theantenna structure230 includes theFM antenna70 and thebattery226 in a spaced-apart relation via thedielectric spacer257. TheFM antenna70 has a planar structure generally corresponding to thedielectric spacer257 and a conductive layer that provides theground plane224. TheFM antenna70 has aprotective layer225 and anantenna trace218, which face adjacent to a first side of thedielectric spacer257. A conductive layer forming aground plane224 is positioned adjacent a second side of thedielectric spacer257, and thebattery226 is in turn adjacent theground plane224.
• In this manner, the planar structure of theFM antenna70 and the planar surface of thebattery226 are substantially parallel to each other in a spaced-apart relation, which serves to improve the FM performance of theFM antenna70. Further, thegap231 provides a further dielectric effect with respect to theantenna structure230, in that a level of electrical insulation between theantenna structure231 and the case covers is provided while supporting electrostatic fields conducive to FM antenna operation.
• As one of average skill in the art will appreciate, the term “substantially” or “approximately”, as may be used herein, provides an industry-accepted tolerance to its corresponding term. Such an industry-accepted tolerance ranges from less than one percent to twenty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. As one of average skill in the art will further appreciate, the term “coupled”, as may be used herein, includes direct coupling and indirect coupling via another component, element, circuit, or module where, for indirect coupling, the intervening component, element, circuit, or module does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As one of average skill in the art will also appreciate, inferred coupling (that is, where one element is coupled to another element by inference) includes direct and indirect coupling between two elements in the same manner as “coupled”. As one of average skill in the art will further appreciate, the term “compares favorably”, as may be used herein, indicates that a comparison between two or more elements, items, signals, et cetera, provides a desired relationship. For example, when the desired relationship is that a first signal has a greater magnitude than a second signal, a favorable comparison may be achieved when the magnitude of the first signal is greater than that of the second signal or when the magnitude of the second signal is less than that of the first signal. While the transistors or switches in the above described figure(s) is/are shown as field effect transistors (FETs), as one of ordinary skill in the art will appreciate, the transistors may be implemented using any type of transistor structure including, but not limited to, bipolar, metal oxide semiconductor field effect transistors (MOSFET), N-well transistors, P-well transistors, enhancement mode, depletion mode, and zero voltage threshold (VT) transistors.

Claims (23)

1. An integrated circuit that supports wireless communications comprises:

wireless communication circuitry coupled to convert an inbound RF signal into an inbound data signal and to convert an outbound data signal into an outbound RF signal;

FM receiver circuitry coupled to convert an inbound continuous wavelength signal into an inbound FM data signal; and

FM antenna control circuitry coupled to the FM receiver circuitry, the FM antenna control circuitry producing control signals to control a center frequency of a gain profile of an FM antenna.

2. The integrated circuit ofclaim 1, wherein the control signals control switches of an external lumped element tuning array.

3. The integrated circuit ofclaim 1, wherein the FM antenna control circuitry comprises:

a plurality of switches to produce the control signals, wherein the plurality of switches change an impedance of external lumped tuning elements based upon the control signals.

4. The integrated circuit ofclaim 1 further comprises:

lumped tuning elements coupled to the control signals, wherein the control signals change an impedance of the lumped tuning elements.

5. The integrated circuit ofclaim 1 further comprises:

a cellular interface coupled to the wireless communication circuitry that supports wireless data transmission.

6. The integrated circuit ofclaim 1 further comprises:

FM transmitter circuitry coupled to convert an outbound FM data signal to an outbound continuous wavelength signal for broadcast.

7. The integrated circuit ofclaim 1 wherein the inbound data signal is at least one of a low intermediate frequency (IF) signal and a baseband signal based upon a local oscillation.

8. The integrated circuit ofclaim 1 wherein the wireless communication circuitry accommodates at least one of:

an IEEE 802.11 wireless standards specification;

a Bluetooth wireless standards specification;

an advanced mobile phone services (AMPS) wireless standards specification;

a digital AMPS wireless standards specification;

a global system for mobile communications (GSM) wireless standards specification;

a code division multiple access (CDMA) wireless standards specification;

a local multi-point distribution systems (LMDS) standards specification; and

a multi-channel multi-point distribution systems (MMDS) standards specification.

9. A portable device that supports wireless communications comprising:

processing circuitry;

a cellular network interface coupled to the processing circuitry that supports wireless data transmission with a base transceiver station;

a user interface coupled to the processing circuitry that supports user input/output;

memory coupled to the processing circuitry, wherein the memory stores operational instructions that cause the processing circuitry to:

convert an inbound RF signal into an inbound data signal and convert an outbound data signal into an outbound RF signal;

convert an inbound continuous wavelength signal into an inbound FM data signal; and

generate control signals to control a center frequency of a gain profile of an FM antenna.

10. The portable device ofclaim 9, wherein the control signals control switches of an external lumped element tuning array.

11. The portable device ofclaim 9, wherein the control signals change an impedance of external lumped tuning elements.

12. The portable device ofclaim 9, wherein the memory further stores operational instructions that cause the processing circuitry to:

convert an outbound FM data signal to an outbound continuous wavelength signal for broadcast.

13. The portable device ofclaim 9 wherein the inbound data signal is at least one of a low intermediate frequency (IF) signal and a baseband signal based upon a local oscillation.

14. The portable device ofclaim 9 wherein the wireless data transmission accommodates at least one of:

an IEEE 802.11 wireless standards specification;

a Bluetooth wireless standards specification;

an advanced mobile phone services (AMPS) wireless standards specification;

a digital AMPS wireless standards specification;

a global system for mobile communications (GSM) wireless standards specification;

a code division multiple access (CDMA) wireless standards specification;

a local multi-point distribution systems (LMDS) standards specification; and

a multi-channel-multi-point distribution systems (MMDS) standards specification.

15. A wireless handheld device comprising:

a case;

an FM antenna;

a conductive layer providing a ground plane to the FM antenna, the conductive layer adjacent the FM antenna in an electrostatic field relation;

a battery, the battery positioned adjacent an opposite side of the conductive layer, wherein the FM antenna and the battery are substantially parallel to each other in a spaced-apart relation improving performance of the FM antenna;

wireless communication circuitry disposed within the case and coupled to convert an inbound RF signal into an inbound data signal and to convert an outbound data signal into an outbound RF signal;

FM receiver circuitry coupled to convert an inbound continuous wavelength signal into an inbound FM data signal; and

FM antenna control circuitry coupled to the FM receiver circuitry, the FM antenna control circuitry having control signals to control a center frequency of a gain profile of the FM antenna.

16. The wireless handheld device ofclaim 15, wherein the control signals control switches of an external lumped element tuning array.

17. The wireless handheld device ofclaim 15, wherein the FM antenna control circuitry comprises:

a plurality of switches to produce the control signals, wherein the plurality of switches change an impedance of external lumped tuning elements through the control signals.

18. The wireless handheld device ofclaim 15 further comprises:

lumped tuning elements coupled to the control signals, wherein the control signals change an impedance of the lumped tuning elements.

19. The wireless handheld device ofclaim 15 further comprises:

FM transmitter circuitry coupled to convert an outbound FM data signal to an outbound continuous wavelength signal for broadcast through the FM antenna.

20. The wireless handheld device ofclaim 15, wherein the FM antenna further comprises:

an input/output connection coupled to the transceiver circuitry.

21. The wireless handheld device ofclaim 20 wherein the input/output connection comprises at least one of:

a coaxial probe, a printed microstrip, a waveguide, and a coplanar transmission line.

22. The wireless handheld device ofclaim 15 wherein the FM antenna comprises at least one of a monopole, a dipole, an eccentric spiral and a fractal antenna.

23. The wireless handheld device ofclaim 15 wherein the wireless communication circuitry accommodates at least one of:

an IEEE 802.11 wireless standards specification;

a Bluetooth wireless standards specification;

an advanced mobile phone services (AMPS) wireless standards specification;

a digital AMPS wireless standards specification;

a global system for mobile communications (GSM) wireless standards specification;

a code division multiple access (CDMA) wireless standards specification;

a local multi-point distribution systems (LMDS) standards specification; and

a multi-channel multi-point distribution systems (MMDS) standards specification.

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