(12)
`
`United States Patent
`Scheer et al.
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 8.204,446 B2
`Jun. 19, 2012
`
`USOO8204446B2
`
`(54) ADAPTIVE ANTENNA TUNING SYSTEMS
`AND METHODS
`
`(*) Notice:
`
`(75) Inventors: Roger Scheer, Beach Park, IL (US);
`Eric Krenz, Crystal Lake, IL (US);
`Istvan Szini, Grayslake, IL (US
`y
`(US)
`(73) Assignee: Motorola Mobility, Inc., Libertyville, IL
`(US)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 419 days.
`(21) Appl. No.: 12/608,604
`(22) Filed:
`Oct. 29, 2009
`(65)
`Prior Publication Data
`
`May 5, 2011
`
`US 2011 FO105O23 A1
`(51) Int. Cl.
`(2006.01)
`H04B I7/00
`(52) U.S. Cl. ................... iss671.45s/120.45s,193.1
`f
`(58) Field of Classification Search ................. 455/3.01,
`455/3.03, 62, 63.1, 67.11, 115.1, 2. 129,
`lication file f
`1
`hhi 455/1931
`S
`ee application file for complete search history.
`References Cited
`
`(56)
`
`U.S. PATENT DOCUMENTS
`4.201960 A
`5, 1980 Skutta et al.
`6,657,595 B1
`12/2003 Phillips et al.
`
`1/2007 Kipnis et al.
`7,167,135 B2
`4/2007 Liu et al.
`7,199,762 B2
`7,633,909 B1* 12/2009 Jones et al. ................... 370,338
`2007/0042710 A1
`2/2007 Mahini et al. ................ 455,303
`2007/0232367 A1 10, 2007 Kasha et al.
`2011/0237.196 A1* 9, 2011 Niu et al. ........................ 455,62
`FOREIGN PATENT DOCUMENTS
`0047354 A1
`3, 1982
`EP
`* cited by examiner
`
`Primary Examiner — Thanh Le
`
`ABSTRACT
`(57)
`Embodiments include antenna tuning systems and methods
`of tuning an antenna of a wireless device with an antenna, a
`circuit with at least one tunable component, and a processing
`system. The processing system determines tuning selection
`inputs during a communication session. Based on the tuning
`selection inputs, the processing system determines one or
`more component values for one or more tunable components.
`In an embodiment, the component value(s) are determined
`from a set of pre-defined component values. The unable
`component(s) are controlled to have the determined compo
`nent value(s). The circuit may be an impedance matching
`circuit that includes at least one tunable reactive component.
`Alternatively, the circuit may be an antenna tuning circuit that
`includes at least one variable component. In an embodiment,
`both an impedance matching circuit and an antenna tunin
`p
`9.
`9.
`circuit may be implemented, with each type of circuit having
`one or more tunable components.
`
`23 Claims, 5 Drawing Sheets
`
`200 \
`
`
`
`
`
`
`
`SER
`DETERMINE COMPONENTWALU
`MATCHING AND ORTUNINGC
`
`26
`
`oryzg
`
`AES
`
`
`
`YES
`STORHISTORICINFORMATION
`
`NO
`
`224
`
`CALL
`
`ERMA's
`
`LUMENIS EX1079
`Page 1
`
`

`

`U.S. Patent
`
`Jun. 19, 2012
`
`Sheet 1 of 5
`
`US 8.204,446 B2
`
`f00
`\
`
`
`
`114
`
`USER INTERFACE
`130
`132
`SPKRPH
`
`MIC
`
`134
`
`SPKR
`
`f10
`
`DATA
`STORAGE
`
`164
`
`120
`
`VSWR
`DETECTOR
`
`172
`
`102
`
`a
`
`PROCESSING
`
`SYSTEM
`
`TRANSCEIVER
`
`MATCHING
`CIRCUIT
`
`TUNING
`CIRCUIT
`
`ANTENNA
`
`FIG. I.
`
`LUMENIS EX1079
`Page 2
`
`

`

`U.S. Patent
`
`Jun. 19, 2012
`
`Sheet 2 of 5
`
`US 8.204,446 B2
`
`200
`
`
`
`
`
`
`
`
`
`
`
`202
`
`204
`
`206
`
`RECEIVE MEASURABLEISENSABLE INPUTS
`
`VOICE, DATA
`OR OTHER2
`
`210
`208
`VOICE DETERMINE USER
`IDENTITY
`
`DATA OR OTHER
`DETERMINE OR PREDICTSRRCHARACTERISTICS-2
`AND FACIAL PROXIMITY
`14 2
`
`DETERMINE COMPONENT VALUE(S) FOR
`MATCHING AND/ORTUNING CIRCUIT
`
`216
`
`SET COMPONENT(S) TO THE COMPONENT
`VALUE(S)
`
`TUNING
`
`so off"
`OPTIZED
`BS
`YES
`222
`STORE HISTORIC INFORMATION
`
`224
`
`CALL
`ERMINATED
`
`YES
`
`FIG. 2
`
`LUMENIS EX1079
`Page 3
`
`

`

`U.S. Patent
`
`Jun. 19, 2012
`
`Sheet 3 of 5
`
`US 8.204,446 B2
`
`SS
`
`S
`
`S
`
`
`
`S
`
`M
`S
`
`S
`
`s
`
`LUMENIS EX1079
`Page 4
`
`

`

`U.S. Patent
`
`Jun. 19, 2012
`
`Sheet 4 of 5
`
`US 8,204,446 B2
`
`S79
`
`v2ES‘VS
`
`eevs‘LP
`
`geESES
`
`9°9‘vr‘S'S
`
`Velevl
`
`g¢‘1S‘79
`
`6S‘02'€'9
`
`
`
`Lg‘'06
`
`02‘VS'¢'9
`
`9°9‘72'9'8
`
`erOe‘99
`
`AMALNSNOdNOD
`
`
`
`(4d)€9'29‘19
`
`UNS
`
`Hd
`
`cor ‘ON
`
`9¢F
`iServ
`ker
`
`Gch
`
`86h
`
`kev
`
`A
`
`leb
`
`"|
`
`WO
`
`pAdd
`
`Al
`
`LUMENIS EX1079
`Page 5
`
`LUMENIS EX1079
`Page 5
`
`
`
`

`

`U.S. Patent
`
`Jun. 19, 2012
`Jun. 19, 2012
`
`Sheet 5 of 5
`Sheet 5 of 5
`
`US 8.204,446 B2
`US 8,204,446 B2
`
`
`
`WIS
`
`NISWIL
`
`ONINNL
`
`ALVIS
`
`NOILOA1S$ EIS
`
`AYOLSIH
`
`Ç (5) I. H
`
`40S
`
`209
`60S
`
`809
`€0S
`
`þ09
`v0S
`
`00S
`
`LUMENIS EX1079
`Page 6
`
`LUMENIS EX1079
`Page 6
`
`

`

`1.
`ADAPTIVE ANTENNA TUNING SYSTEMS
`AND METHODS
`
`US 8,204,446 B2
`
`TECHNICAL FIELD
`
`The inventive subject matter relates generally to wireless
`communications, and more particularly to antenna tuning in a
`wireless communication device.
`
`BACKGROUND
`
`10
`
`15
`
`25
`
`30
`
`35
`
`40
`
`Due primarily to consumer preferences, the physical sizes
`of wireless handheld communication devices continue to
`shrink while the number of features provided continues to
`increase. In addition, various wireless devices are now
`designed to Support communications within multiple fre
`quency bands. Each of these developments has impacted the
`design and performance of antenna systems within contem
`porary wireless devices.
`As is well known, an antenna system of a wireless device
`provides a means by which radio frequency (RF) power may
`be radiated into or detected from the environment. Although
`previous generations of wireless devices commonly included
`externally protruding antennas, the antennas of many current
`wireless devices are completely enclosed within a devices
`housing. Accordingly, an antenna occupies some portion of
`the physical volume within the device's housing. The con
`tinuing drive toward Smaller devices places ever-increasing
`constraints on the amount of space that may be allotted for
`antenna Volumes. In addition, some wireless devices that are
`designed to Support communications within multiple fre
`quency bands include multiple antennas (e.g., one antenna for
`each Supported frequency band), thus increasing the space
`required for the antenna system, despite the drive toward
`smaller device sizes. Other wireless devices are designed to
`Support communications using multiple communications
`protocols on separate frequency bands, again warranting the
`inclusion of multiple antennas in a single wireless device.
`Along with issues relating to antenna Volumes, the charac
`teristics of housing-enclosed antenna systems also raise
`issues relating to performance. More particularly, the perfor
`mance of an enclosed antenna may be significantly affected
`by the manner in which a device user holds the wireless
`device during operation. For example, the compact designs of
`Some wireless devices enable a user to enclose significant
`45
`portions of the device's housing in the users hand. In addi
`tion, a user may be inclined to press the front surface of the
`device's housing against the user's face, and accordingly a
`significant portion of the front Surface may be in contact with
`the user during device operation. The degree of contact
`between a wireless device and a user's body (e.g., the user's
`hand and face) may significantly and detrimentally affect the
`radiation efficiency of the device's antenna (e.g., by perturb
`ing an antenna element's resonant frequency).
`More recently, the inclusion of impedance matching cir
`55
`cuits in wireless devices has facilitated the development of
`relatively compact, enclosed antenna systems that may pro
`vide reliable communications over multiple frequency bands.
`Essentially, an impedance matching circuit may be tuned to
`provide an impedance match for the antenna at a desired
`operating frequency. Adaptive tuning of the impedance
`matching circuit in conventional devices is driven by feed
`back data received from the RF system (e.g., information
`pertaining to the transmit path and the receive path) and/or
`information regarding the physical environment around the
`wireless device. Unfortunately, current systems adapted to
`provide complete, accurate, and dependable information
`
`50
`
`60
`
`65
`
`2
`about the receive path and the physical environment around
`the wireless device tend to be costly, complex, and difficult to
`implement.
`Accordingly, what are needed are methods and apparatus
`for tuning an impedance matching circuit, which may be
`relatively inexpensive, simple, and easy to implement, when
`compared with conventional methods and apparatus. Other
`desirable features and characteristics of the present inventive
`Subject matter will become apparent from the Subsequent
`detailed description and the appended claims, taken in con
`junction with the accompanying drawings and this back
`ground.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 illustrates a simplified diagram of a wireless com
`munication device within which an adaptive antenna tuning
`system is incorporated, in accordance with an example
`embodiment;
`FIG. 2 illustrates a flowchart of a method for selecting and
`setting impedance matching component values for compo
`nents of an impedance matching circuit, in accordance with
`an example embodiment;
`FIG. 3 illustrates an example of an impedance matching
`circuit, in accordance with an example embodiment;
`FIG. 4 illustrates an example of a component value lookup
`table, in accordance with an example embodiment; and
`FIG.5 illustrates an example of a historic selection table, in
`accordance with an example embodiment.
`
`DETAILED DESCRIPTION
`
`The following detailed description is merely exemplary in
`nature and is not intended to limit the inventive subject matter
`or the application and uses of the inventive subject matter.
`Furthermore, there is no intention to be bound by any theory
`presented in the preceding background or the following
`detailed description.
`Embodiments described herein include adaptive antenna
`tuning systems and methods. As will be described in detail
`below, a wireless communication device includes the antenna
`and one or more circuits, which may be controlled to affect
`the antenna tuning (e.g., matching circuit 106 and/or tuning
`circuit 107, FIG. 1). An embodiment of a method for adap
`tively tuning the antenna includes determining one or more
`tuning selection inputs in conjunction with a wireless com
`munication session that is Supported by the wireless commu
`nication device. The method also includes determining, based
`on the tuning selection inputs, values for one or more com
`ponents of the antenna tuning and/or matching circuits.
`According to an embodiment, the component values are
`determined from a set of pre-defined component values (e.g.,
`within a lookup table). The components are adjusted to have
`the determined component values.
`FIG. 1 illustrates a simplified diagram of a wireless com
`munication device 100 within which an adaptive antenna
`system is incorporated, in accordance with an example
`embodiment. Device 100 may be a cellular telephone, accord
`ing to an embodiment, although device 100 may be some
`other type of wireless communication apparatus, in other
`embodiments (e.g., a one-way or two-way radio, a computer,
`a personal data assistant (PDA), a pager, a wireless personal
`area network (WPAN) compatible device, or some other type
`of wireless communication apparatus). According to an
`embodiment, device 100 includes a processing system 102, a
`transceiver 104, at least one matching circuit 106, at least one
`antenna 108, data storage 110, a user interface 112, and a
`
`LUMENIS EX1079
`Page 7
`
`

`

`3
`housing 114. According to further embodiments, device 100
`also may include a voltage standing wave ratio (VSWR)
`detector 120 and/or one or more proximity or other types of
`sensors 122.
`Processing system 102 may include, for example, one or
`more general-purpose or special-purpose microprocessors,
`application specific integrated circuits (ASICs), digital-to
`analog converters (DACs), analog-to-digital converters
`(ADCs), reference generators, clocks, and/or associated cir
`cuitry. According to an embodiment, processing system 102
`is adapted, during operation, to control the functionality of
`matching circuit 106 and/or tuning circuit 107 by selecting
`one or more component values for one or more components of
`matching circuit 106 and/ortuning circuit 107. Once selected,
`processing system 102 provides control signals 150 to match
`ing circuit 106 and/or tuning circuit 107, which cause match
`ing circuit 106 and/or tuning circuit 107 to set the associated
`components to the indicated component values (e.g., to
`“tune' antenna 108). As will be described in more detail
`below, selection of the component values is performed based
`on one or more “tuning selection inputs' that are received or
`determined by processing system 102. In addition, the com
`ponent values may be selected from a set of pre-defined
`component values, which may be stored within data storage
`110, for example.
`Matching circuit 106 may include, for example but not by
`way of limitation, a matching network, a balun, an antenna
`tuner, a transmatch or an antenna tuning unit (ATU). Match
`ing circuit 106 is coupled with antenna 108, and is adapted,
`during operation, to provide an input impedance to antenna
`108, where the input impedance may be varied by adjusting
`the values of one or more passive or active impedance match
`ing components (not illustrated in FIG. 1) of matching circuit
`106. More particularly, matching circuit 106 includes at least
`one reactive component (e.g., capacitors, inductors, or other
`components), which has a value that may be varied under the
`command or control of processing system 102 (via control
`signals 150). According to an embodiment, the impedance
`matching component values are selected (e.g., by processing
`system 102) So that the input impedance of matching circuit
`106 closely matches the load impedance of antenna 108, in
`order to maximize the power transfer and minimize reflec
`tions from antenna 108. The impedance matching compo
`nents of matching circuit 106 may include, for example, one
`or more reactive components (e.g., capacitors, inductors),
`transformers, Switchable elements (e.g., transistors), and/or
`resistive components (e.g., resistors). An example of a match
`ing circuit 106 will be discussed later in conjunction with
`FIG. 3.
`Tuning circuit 107 may include, for example but not by
`way of limitation, a tunable circuit and a parasitic tuning
`element and/or an active tuning element (e.g., a Switching
`ground connection). Tuning circuit 107 is coupled with
`antenna 108, and is adapted, during operation, to drive the
`parasitic and/or active tuning element, thus affecting the fre
`quency characteristics of antenna 108. One or more of the
`tuning circuit component values may be varied, according to
`an embodiment. More particularly, tuning circuit 107
`includes at least one variable component (e.g., capacitors,
`inductors, or other components), which has a value that may
`be varied under the command or control of processing system
`102 (via control signals 163).
`Transceiver 104 is coupled between processing system 102
`and matching circuit 106, and includes a transmitter and a
`receiver. In accordance with providing a transmit function,
`transceiver 104 receives baseband digital signals 152 from
`processing system 102, and the transmitter portion of trans
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`US 8,204,446 B2
`
`10
`
`15
`
`4
`ceiver 104 filters and processes the digital signals, converts
`the resulting digital signals to analog signals, and amplifies
`and upconverts the analog signals to produce a radio fre
`quency (RF) analog signal 154 intended for transmission. In
`accordance with providing a receive function, transceiver 104
`receives RF analog signals 156, amplifies and downconverts
`the analog signals, converts the resulting analog signals to
`digital signals, and processes the digital signals to produce a
`baseband digital signal 158 that is ready for further process
`ing by processing system 102.
`Antenna 108 is coupled with matching circuit 106 and
`tuning circuit 107, and may include, for example, a single
`antenna element or a plurality of antenna elements. Upon
`receipt of an analog signal 160 from matching circuit 106.
`antenna 108 is adapted to radiate RF power corresponding to
`the analog signal into the environment. In addition, antenna
`108 is adapted to detect RF power from the environment, and
`to provide corresponding analog signals 162 to matching
`circuit 106. The frequency characteristics of antenna 108 may
`be affected by tuning circuit 107, as mentioned previously.
`According to an embodiment, antenna 108 is completely
`contained within housing 114, although antenna 108 may
`partially or completely extend outward from housing 114, or
`antenna 108 may be embedded in or be formed from part of
`housing 114, in other embodiments. The housing 114 and/or
`internal printed circuit boards (not illustrated) may act as
`ground planes for antenna 108. Although only a single
`antenna 108, transceiver 104, matching circuit 106, and tun
`ing circuit 107 are shown in FIG. 1, it is to be understood that
`multiple instantiations of these components may be included
`in a device, in order to implement antenna diversity (e.g.,
`multiple-in, multiple-out (MIMO) antenna arrays), commu
`nications within different frequency bands, and/or communi
`cations using different communications protocols.
`Data storage 110 may include, for example, one or more
`data storage devices that are separate from or integral with
`processing system 102. Data 164 may be stored by processing
`system 102 within data storage 110, or retrieved by process
`ing system 102 from data storage 110. For example, data
`storage 110 may include a combination of various types of
`non-volatile and volatile read only memory (ROM) and ran
`dom access memory (RAM). According to an embodiment,
`data storage 110 is adapted to store pre-defined component
`values for at least those components of matching circuit 106
`and/or tuning circuit 107 that are variable. As will be
`described in more detail later, the pre-defined component
`values may be stored in the form of a lookup table, where each
`entry of the table may include values for one or more imped
`ance matching components. An entry is selected by process
`ing system 102 based on one or more tuning selection inputs,
`according to an embodiment. Accordingly, for example, the
`lookup table may be implemented in the form of a relational
`table, where the tuning selection inputs are used to select
`entries within the table that have certain attributes (e.g.,
`attributes corresponding to the tuning selection inputs).
`According to an embodiment, data storage 110 also may be
`adapted to store information that enables a correlation
`between a user identity and historically selected component
`values, as will also be described in more detail later.
`User interface 112 may include a plurality of devices that
`enable a user and device 100 to interact. For example, user
`interface 112 may include a microphone (MIC) 130, a speak
`erphone (SPKRPH) 132, a speaker (SPKR) 134, a keypad, a
`display, a touchscreen, and any of a number of other types of
`user interface devices. A detailed description of the function
`ality of various user interface devices is out of the scope of
`this description, however, certain embodiments may employ
`
`LUMENIS EX1079
`Page 8
`
`

`

`US 8,204,446 B2
`
`10
`
`15
`
`25
`
`35
`
`5
`information pertaining to the MIC 130, SPKRPH 132, and/or
`SPKR 134, and therefore the functionality of these system
`elements will be briefly described. MIC 130 is adapted, dur
`ing operation, to convert environmental vibrations (particu
`larly associated with speech) into an analog audio signal 170,
`and to provide the analog audio signal 170 to processing
`system 102. As will be described in more detail later, process
`ing system 102 may evaluate the analog audio signal 170 to
`determine a signal-to-noise ratio (SNR), and the SNR may
`indicate one type of tuning selection input, according to an
`embodiment. SPKRPH 132 is adapted, during operation, to
`receive analog audio signals 172 from processing system 102.
`to amplify the analog audio signal 172 to a relatively high
`level associated with a speakerphone, and to produce Sound
`from the amplified analog signal. Similarly, SPKR 134 is
`adapted, during operation, to receive analog audio signals 172
`from processing system 102, to amplify the analog audio
`signal 172 to a relatively low level associated with a speaker
`that is proximate to an ear, and to produce Sound from the
`amplified analog signal. Typically, only one of SPKRPH 132
`or SPKR 134 is active at any given time, and the activation is
`performed based on user inputs. According to an embodi
`ment, the activation states of SPKRPH 132 and/or SPKR 134
`is known by or accessible to processing system 102, and the
`activation state may indicate another type of tuning selection
`input. Detection of whether SPKRPH 132 or SPKR 134 is
`active is an indication of a user mode in which device 100 is
`being used.
`VSWR detector 120 is coupled between the output of
`30
`matching circuit 106 and the input to antenna 108. VSWR
`detector 120 is adapted, during operation, to monitor actual
`forward and reflected RF power 180 in order to calculate a
`VSWR measurement 182, that VSWR detector 120 may pro
`vide to processing system 102. VSWR measurements 182
`may be expressed using S-parameters (Scattering param
`eters), for example. According to an embodiment, VSWR
`detector 120 includes a 4-port directional coupler, with a main
`line input and output ports being connected to the output of
`matching circuit 106 and the input to antenna 108, respec
`40
`tively. Both coupled ports of the coupler are connected to
`corresponding RF power sensors, which provide data about
`measured forward and reflected RF power levels. As will be
`described in more detail later, VSWR measurements 182 may
`indicate yet another type of tuning selection input, and may
`45
`also or alternatively be used to determine whether tuning of
`matching circuit 106 and/or tuning circuit 107 is optimized.
`Sensors 122 may be disposed within or on housing 114 at
`various locations. According to an embodiment, at least some
`of sensors 122 are adapted, during operation, to detect the
`proximity of the device to external objects, such as parts of a
`user's body or other objects, for example. Sensors 122 may
`include, for example but not by way of limitation, one or more
`capacitive sensors, infrared (IR) proximity sensors, pressure
`sensors, or other types of sensors. A capacitive sensor may be
`activated when a nominally conductive material (e.g., a user's
`hand or cheek) contacts or is Sufficiently close to the sensor.
`An IR proximity sensor may be activated when it is in proX
`imity with any material that scatters IR energy. One or more
`sensors 122 may be positioned, for example, on the front,
`back, and/or sides of the phone housing. According to another
`embodiment, sensors 122 may include one or more acceler
`ometers, which may enable a determination of whether the
`wireless device 100 is being used in a portrait or landscape
`mode, for example. According to an embodiment, sensors
`122 provide signals 184 to processing system 102, which may
`indicate yet another type of tuning selection input.
`
`50
`
`55
`
`60
`
`65
`
`6
`As mentioned previously, processing system 102 may
`receive and/or determine a variety of tuning selection inputs,
`and based on the tuning selection inputs, processing system
`102 may determine component values for one or more imped
`ance matching components of matching circuit 160. For
`example, as mentioned previously, processing system 102
`may access a lookup table (e.g., a table stored in data storage
`110), and may select, based on the tuning selection inputs, an
`entry of the lookup table that includes various, pre-defined
`component values. Processing system 102 may then “tune'
`the matching circuit 160 by providing control signals 150,
`which result in the values of the impedance matching com
`ponents being set to the selected values. According to various
`embodiments, the tuning selection inputs may include any
`one or more types of information selected from a group of
`information types that includes:
`a call type indicating whether the wireless communication
`session is a voice communication session or a data com
`munication session,
`a description of a channel assigned for the communication
`session,
`a speakerphone activation indicator,
`a speaker activation indicator,
`a Bluetooth activation indicator,
`a user identity,
`information characterizing a grip with which a user is
`holding the wireless communication device,
`information characterizing a physical proximity of the
`wireless communication device to the body of the user,
`a sensor input,
`a VSWR measurement, and
`an SNR measurement.
`Characteristics of the physical and communications envi
`ronments within which antenna 108 operates (e.g., character
`istics of the user's grip, the proximity of wireless device 100
`to the user's face, a communication frequency, and so on)
`may significantly affect the impedance of antenna 108. For
`example, when a communication device is tightly gripped
`(e.g., cradled) and held against the face, the impedance of
`antenna 108 may be significantly lower than when the com
`munication device is used in a hands-free mode (e.g., placed
`on a desk during operation). In addition, the impedance of
`antenna 108 may be predictably higher when communicating
`at a certain frequency (or within a certain frequency band)
`than it is when communicating at a different frequency (or
`within a different frequency band). According to various
`embodiments, the above-listed tuning selection inputs may be
`used to directly sense and/or predict characteristics of the
`physical and/or communications environments, and those
`characteristics of the physical and/or communications envi
`ronments may be used in the process of selecting impedance
`matching component values, as will be described in more
`detail in conjunction with FIGS. 2-5.
`FIG. 2 illustrates a flowchart of a method for selecting and
`setting impedance matching component values of an imped
`ance matching circuit, in accordance with an example
`embodiment. According to an embodiment, the method may
`be performed within the context of a “call.” where a “call
`refers to any type of communication session in which a wire
`less device transmits RF signals (e.g., a Voice communication
`session or a data communication session). The method may
`run continuously for a duration of the call, or may be executed
`periodically, aperiodically or in response to a triggering event
`(e.g., a handoff, a change in a value of a tuning selection input,
`or some other event).
`Embodiments of the method may be performed by a pro
`cessing system (e.g., processing system 102, FIG. 1) in con
`
`LUMENIS EX1079
`Page 9
`
`

`

`US 8,204,446 B2
`
`10
`
`15
`
`25
`
`35
`
`7
`junction with a matching circuit (e.g., matching circuit 106),
`a tuning circuit (e.g., tuning circuit 107), and various other
`system elements that may provide tuning selection inputs
`and/or that may enable tuning selection inputs to be deter
`mined or predicted. According to an embodiment, the method
`may begin, in block 202, when the processing system receives
`an indication that a call has been initiated or is in progress.
`This may include, for example, receiving an indication that a
`user has pressed a “SEND” button or receiving an input from
`a system component (e.g., transceiver 104 or user interface
`112, FIG. 1) that indicates that a call is being initiated, estab
`lished or is otherwise in progress.
`In block 204, the processing system may determine one or
`more of a first type of tuning selection input, which are
`referred to herein as “call characterization inputs.” A call
`characterization input may include, for example, information
`relating to an established setting for the communication ses
`sion or describing the use mode of the wireless device. For
`example, but not by way of limitation, call characterization
`inputs may include an indication of a call type (e.g., whether
`the call is a voice communication session, a data communi
`cation session, or another type of communication session,
`such as a WiFi, WiMax, video, or other type of session), a
`channel or band allocated for the call (e.g., a frequency or
`frequency band), a speakerphone activation indictor (e.g.,
`indicating whether the speakerphone is in an activated or
`deactivated State), a speaker activation indictor (e.g., indicat
`ing whether the speaker is in an activated or deactivated State),
`and a Bluetooth activation indicator (e.g., indicating whether
`or not the wireless device is currently configured to commu
`30
`nicate using a Bluetooth protocol), among other things. As
`will be described in more detail later, anyone or more of these
`tuning selection inputs may be used directly during the pro
`cess of selecting component values (i.e., block 214 discussed
`below). Alternatively, they may be used to predict the char
`acteristics of a user's grip and/or the proximity of the wireless
`device to the user's face (or other body part) (i.e., block 212
`also discussed below), and the grip and/or facial proximity
`predictions may be used during the component value selec
`tion process (i.e., block 214).
`In block 206, the processing system may receive one or
`more of a second type of tuning selection input, which are
`referred to herein as “measurable/sensable inputs.” A mea
`Surable/sensable input may include, for example, information
`received from a proximity sensor (e.g., one or more of sensors
`122, FIG.1), VSWR measurements (e.g., from VSWR detec
`tor 120, FIG. 1), and audio data (e.g., from MIC 130, FIG. 1)
`that enables calculation of an SNR or other metric.
`According to an embodiment, the processing system also
`may use knowledge of or a prediction of a user's identity (user
`ID) during the process of selecting component values. This
`information may be relevant, for example, because each user
`may tend to grip a wireless device and hold it to the user's
`headina consistent manner (although in a manner that may be
`different from other users). According to an embodiment, the
`processing system maintains historical data for each known
`user, where the historical data may include a description of
`characteristics of the users typical grip and head proximity,
`and/or a listing of one or more previously selected component
`values (e.g., entry numbers within a lookup table of compo
`nent values).
`A user ID may not be relevant in the selection of compo
`nent values during a data communication session. Therefore,
`according to an embodiment, the system may make a deter
`mination, in block 208, whether a voice communication ses
`65
`Sion, a data communication session, or another type of com
`munication session is being conducted. When a Voice
`
`50
`
`40
`
`45
`
`55
`
`60
`
`8
`communication session is being conducted, then the system
`may attempt to identify the user, in block 210. According to an
`embodiment, the system may attempt to identify a user by
`receiving speech data, if it is available (e.g., from MIC 130,
`FIG. 1), and executing speaker recognition software to
`attempt to identify the user from the received speech data.
`According to another embodiment, the user may provide a
`user input to indicate that the user is communicating using the
`wireless device (e.g., a user input via the keypad). The userID
`may be considered to be a third type oftuning selection input.
`In block 212, various ones of the previously received or
`determined tuning selection inputs may be used to determine
`or predict characteristics of the grip with which the wireless
`device is being held, and/or to determine or predict the prox
`imity of the user's face to the wireless device. According to an
`embodiment, the grip characteristics may include agrip tight
`ness factor and a housing coverage factor, each of which may
`be qualified or quantified by a finite number of indicators. For
`example, a grip tightness factor may be quantified by a num
`ber within a range (e.g., from 1 to 10), where the low end of
`the range corresponds to an extremely light grip, and the high
`end of the range corresponds to an extremely tight grip, or
`Vice versa. Alternatively, a grip tightness factor may be quali
`fied by a descriptor of the grip tightness, such as “light'.
`“medium, or “tight.” Similarly, a housing coverage factor
`may be quantified by a number indicating a percentage of the
`housing that is enclosed by the users hand (or hand and face),
`or the housing coverage factor may be qualified by a descrip
`tor of the location of coverage or the amount of coverage. Such
`as “minimal.” “p