Patent Application
20220255239
The present disclosure relates generally to communication devices having multiple antennas that support simultaneous communication channels, and more particularly to communication devices having multiple antennas that support simultaneous communication channels within a configurable housing assembly.
Communication devices, such as smartphones, incorporate a number of antennas to support multiple frequency bands assigned to various types of communication networks. Cellular network technology has developed in stages that are referred to as generations (G). Cellular communications have expanded into multiple communication bands and modulation schemes through the evolution of the telecommunications standard from first generation (1G), second generation (2G), third generation (3G), fourth generation (4G), and now fifth generation (5G). Newer generation radio access technologies (RATs) include additional communications bands and communication techniques that require coordinated use of multiple antennas. Recent designs of communication devices incorporate an increased number of antennas and antenna arrays for spatial diversity, carrier aggregation, dual connectivity, and directional antenna gain using multiple input multiple output (MIMO) operations.
Conventionally, communication devices having a “candy bar” form factor that do not fold or close have an antenna architecture that spaces antennas around a periphery of a unitary housing. Conventional communication devices having a configurable housing with a flip form factor (“flip phone”) are generally smaller with insufficient places to put antennas when closed for antenna isolation. During folding or closing, components in one movable portion of the communication device are brought close to components in the other portion of the communication device, changing antenna performance for certain antennas or antenna arrays. Lower RF bands are affected when the flip phone is folded or closed. When closed, the flip phones lose functionality for simultaneous communication by multiple transceivers.
The description of the illustrative embodiments can be read in conjunction with the accompanying figures. It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements. Embodiments incorporating teachings of the present disclosure are shown and described with respect to the figures presented herein, in which:
According to aspects of the present disclosure, a communication device, a computer program product, and a method enable multi-transceiver communication with antennas supported on opposing portions of a configurable housing assembly. A communication device includes a housing assembly having first and second housing portions connected at respective proximal sides for relative movement between an open position and a closed position about a lateral axis. The first housing portion has a distal side and a proximal side. The first housing portion has first and second lateral sides extending between the proximal side and the distal side. The second housing portion has a distal side and a proximal side. The second housing portion has first and second lateral sides extending between the proximal side and the distal side. The communication devices include at least three antennas each having an elongated shape and configured to communicate in one or more radio frequency (RF) communication bands including a low band. First, second and third antennas are separated when the housing assembly is in the open position. The first antenna is within the first housing portion. The second antenna is within the second housing portion. The third antenna is within one of the first and the second housing portions. The first antenna is proximate to and substantially aligned in parallel with the second antenna and separated from the third antenna when the housing assembly is in the closed position.
The communication device includes a first antenna switch, an RF front end, a housing position sensor, and a controller. The RF front end has a first RF transceiver that communicates via the first antenna and has a second RF transceiver that communicates via a selected one of the second and the third antennas via the first antenna switch. The housing position sensor is within the housing assembly and detects: (i) when the housing assembly is in the closed position; and (ii) when the housing assembly is in an at least partially open position. The controller is communicatively coupled to the first antenna switch and the housing sensor. In response to determining that the housing assembly is in the at least partially open position, the controller configures the first antenna switch in a first state to connect the second RF transceiver to the second antenna. In response to determining that the housing assembly is in the closed position, the controller configures the first antenna switch in a second state to connect the second RF transceiver to the third antenna.
In one or more embodiments, the communication device supports a two-way antenna switch diversity RF architecture. Multiple antennas support various operating modes and use cases. Each RF transceiver chain of the RF architecture is connected to a separate antenna. Each RF transceiver chain includes a transmitter and/or receiver and other supporting functional components that are communicatively connected to a particular antenna for communicating an uplink or a downlink. The communication device can have more than one active RF transceiver chain. Certain RF transceiver chains are switched to avoid potential detrimental effects of having a connected antenna that is close to and thus causes interference with another antenna when the housing is in the closed position. Antennas that are not connected to an RF transceiver chain can be used to detect blocking, such as by a hand or ear of a user of the communication device. For clarity, embodiments of the communication device can have a two piece housing assembly that folds symmetrically. However, aspects of the present disclosure can be used with configurable housings that slide together and extend from each other or attach and detach from each other. In the described embodiments, a symmetric two piece housing assembly is provided as the example device. Aspects of the present disclosure can be used in housing assemblies with more than two connected portions and in housing assemblies having two portions that are not similar in shape.
In the following detailed description of exemplary embodiments of the disclosure, specific exemplary embodiments in which the various aspects of the disclosure may be practiced are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, architectural, programmatic, mechanical, electrical, and other changes may be made without departing from the spirit or scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims and equivalents thereof. Within the descriptions of the different views of the figures, similar elements are provided similar names and reference numerals as those of the previous figure(s). The specific numerals assigned to the elements are provided solely to aid in the description and are not meant to imply any limitations (structural or functional or otherwise) on the described embodiment. It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements.
It is understood that the use of specific component, device and/or parameter names, such as those of the executing utility, logic, and/or firmware described herein, are for example only and not meant to imply any limitations on the described embodiments. The embodiments may thus be described with different nomenclature and/or terminology utilized to describe the components, devices, parameters, methods and/or functions herein, without limitation. References to any specific protocol or proprietary name in describing one or more elements, features or concepts of the embodiments are provided solely as examples of one implementation, and such references do not limit the extension of the claimed embodiments to embodiments in which different element, feature, protocol, or concept names are utilized. Thus, each term utilized herein is to be given its broadest interpretation given the context in which that term is utilized.
As further described below, implementation of the functional features of the disclosure described herein is provided within processing devices and/or structures and can involve use of a combination of hardware, firmware, as well as several software-level constructs (e.g., program code and/or program instructions and/or pseudo-code) that execute to provide a specific utility for the device or a specific functional logic. The presented figures illustrate both hardware components and software and/or logic components.
Those of ordinary skill in the art will appreciate that the hardware components and basic configurations depicted in the figures may vary. The illustrative components are not intended to be exhaustive, but rather are representative to highlight essential components that are utilized to implement aspects of the described embodiments. For example, other devices/components may be used in addition to or in place of the hardware and/or firmware depicted. The depicted example is not meant to imply architectural or other limitations with respect to the presently described embodiments and/or the general invention. The description of the illustrative embodiments can be read in conjunction with the accompanying figures. Embodiments incorporating teachings of the present disclosure are shown and described with respect to the figures presented herein.
Communication device 100 can be one of a host of different types of devices, including but not limited to, a mobile cellular phone, satellite phone, or smart-phone, a laptop, a net-book, an ultra-book, a networked smart watch, or networked sports/exercise watch, and/or a tablet computing device or similar device that can include wireless and/or wired communication functionality. As an electronic device supporting wireless communication, communication device 100 can be utilized as, and also be referred to as, a system, device, subscriber unit, subscriber station, mobile station (MS), mobile, mobile device, remote station, remote terminal, user terminal, terminal, user agent, user device, a Session Initiation Protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), computer workstation, a handheld device having wireless connection capability, a computing device, or other processing devices connected to a wireless modem.
Referring again to the specific component makeup and the associated functionality of communication device 100. In one or more embodiments, communication device 100 includes communication subsystem 111, device memory 112, data storage subsystem 113, and input/output (I/O) subsystem 114. Device memory 112 and each subsystem (111, 113, and 114) are managed by controller 101. Device memory 112 includes program code and applications such as antenna control application 115, communication applications 116, and other application(s) 117 that use communication services. Device memory 112 further includes operating system (OS) 118, firmware interface 119, such as basic input/output system (BIOS) or Uniform Extensible Firmware Interface (UEFI), and firmware 120. Device memory 112 includes antenna configuration data 121 or other computer data 122 used by antenna control application 115.
Processor subsystem 124 of controller 101 executes program code to provide operating functionality of communication device 100. The software and/or firmware modules have varying functionality when their corresponding program code is executed by processor subsystem 124 or secondary processing devices within communication device 100. Processor subsystem 124 of controller 101 can execute program code of antenna control application 115 to configure communication sub system 111.
I/O subsystem 114 includes image capturing device(s) 126. I/O subsystem 114 includes user interface devices such as display device 127, motion detection sensors 128, touch/haptic controls 129, microphone 130, and audio output device(s) 131. I/O subsystem 114 also includes I/O controller 132. In one or more embodiments, motion detection sensors 128 can detect an orientation and movement of the communication device 100 that indicates that the communication device 100 should activate display device 127 or should vertically reorient visual content presented on display device 127. In one or more embodiments, motion detection sensors 128 are used for functions other than user inputs, such as detecting an impending ground impact. I/O controller 132 connects to internal devices 133, which are internal to housing assembly 102 and to peripheral devices 134, such as external speakers, which are external to housing assembly 102 of communication device 100. Examples of internal devices 133 are computing, storage, communication, or sensing components depicted within housing assembly 102. I/O controller 132 supports the necessary configuration of connectors, electrical power, communication protocols, and data buffering to act as an interface to internal devices 133 and peripheral devices 134 to other components of communication device 100 that use a different configuration for inputs and outputs.
Communication sub system 111 of communication device 100 enables wireless communication with external communication system 135. Communication subsystem 111 includes antenna subsystem 136 having lower band antennas 137a-137m and higher band antenna array modules 138a-138n that can be attached in/at different portions of housing assembly 102. Multiple radio frequency (RF) bands, including ultra-low band (UL), low band (LB), mid-band (MB), high band (HB), and ultra-high band (UHB), are supported by the various antennas within the communication devices. Particular public land mobile network (PLMN) and radio access technology (RAT) combinations, as well as services based on 802.11 wireless and global positioning system (GPS) signals, can use one or more of these RF bands.
Communication subsystem 111 includes radio frequency (RF) front end 139 and communication module 140. RF front end 139 includes transceiver(s) 141, which includes transmitter(s) 142 and receiver(s) 143. RF front end 139 further includes modem(s) 144. RF front end 139 includes antenna feed/source networks 145, antenna switch network 146, antenna impedance sensor(s) 147, and antenna matching network(s) 148. Communication module 140 of communication subsystem 111 includes baseband processor 149 that communicates with controller 101 and RF front end 139. Baseband processor 149 operates in baseband frequency range to encode data for transmission and decode received data, according to a communication protocol. Modem(s) 144 modulate baseband encoded data from communication module 140 onto a carrier signal to provide a transmit signal that is amplified by transmitter(s) 142. Modem(s) 144 demodulates each signal received from external communication system 135 detected by antenna subsystem 136. The received signal is amplified and filtered by receiver(s) 143, which demodulate received encoded data from a received carrier signal. Antenna feed/source networks 145 transmits or receives from particular portions of antenna subsystem 136 and can adjust phase between particular portions of antenna subsystem 136. Antenna switch network 146 can connect particular combinations of antennas (137a-137m, 138a-138n) to transceiver(s) 141. Controller 101 can monitor changes in antenna impedance detected by antenna impedance sensor(s) 147 for determining portions of antenna subsystem 136 that are blocked. Antenna matching network(s) 148 are connected to particular lower band antennas 137a-137m to tune impedance respectively of lower band antennas 137a-137m to match impedance of transceivers 141. Antenna matching network(s) 148 can also be used to detune the impedance of lower band antennas 137a-137m to not match the impedance of transceivers 141 to electromagnetically isolate a particular antenna.
Housing position sensor 109 can be one of: (i) a two-position binary switch which detects the closed position and any other position considered partially open position (i.e., not a closed position); (ii) a multiple position switch of discrete values; or (iii) a continuous range sensor. The at least partially open position of housing assembly 102 can be one or more positions greater than 0° and less than 180° defined as pivot angles between first and second housing portions 103a-103b. With each implementation, housing position sensor 109 detects the partially open position based on the two housing portions being a predetermined distance or number of degrees apart from each other (e.g., at 30° or 45°). The distance or number of degrees can be empirically determined to correspond with when the antennas are sufficiently apart for a particular operational mode of communication device 102. As an example, the defined pivot angles can be based on one or more considerations such as: (i) capabilities of housing position sensor 109 (
In one or more embodiments, controller 101, via communication subsystem 111, performs multiple types of over-the-air (OTA) communication with network nodes 150 of external communication system 135. Particular network nodes 150 can be part of communication networks 151 of public land mobile networks (PLMNs) that provide connections to plain old telephone systems (POTS) 152 for voice calls and wide area networks (WANs) 115 for data sessions. WANs 115 can include Internet and other data networks. The particular network nodes 150 can be cells 154 such as provided by base stations or base nodes that support cellular OTA communication using RAT as part of a radio access network (RAN). Unlike earlier generations of cellular services, where voice and data were handled using different RATs, both are now integrated with voice being considered one kind of data communication. Conventionally, broadband, packet-based transmission of text, digitized voice, video, and multimedia communication are provided using Fourth generation (4G) RAT of evolved UTMS radio access (E-UTRA), referred to a Long Term Evolved (LTE), although some cellular data service is still being provided by third generation (3G) Universal Mobile Telecommunications Service (UMTS). A fifth generation (5G) RAT, referred to as fifth generation new radio (5G NR), is being deployed to at least augment capabilities of 4G LTE with a yet higher capability of data transfer. Development continues for what will be six generation (6G) RATs and more advanced RATs.
In one or more embodiments, network nodes 150 can be access node(s) 155 that support wireless OTA communication. Communication subsystem 111 can receive OTA communication from location services such as provided by global positioning system (GPS) satellites 156. Communication subsystem 111 communicates via OTA communication channel(s) 158a with cells 154. Communication subsystem 111 communicates via wireless communication channel(s) 158b with access node 155. In one or more particular embodiments, access node 155 supports communication using one or more IEEE 802.11 wireless local area network (WLAN) protocols. Wi-Fi is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used between user devices and network devices that provide Internet access. In one or more particular embodiments, communication subsystem 111 communicates with one or more locally networked devices 159 via wired or wireless link 158c provided by access node 155. Communication subsystem 111 receives downlink broadcast channel(s) 158d from GPS satellites 156 to obtain geospatial location information.
In one or more embodiments, controller 101, via communication subsystem 111, performs multiple types of OTA communication with local communication system 160. In one or more embodiments, local communication system 160 includes wireless headset 161 and smart watch 162 that are coupled to communication device 100 to form a personal access network (PAN). Communication subsystem 111 communicates via low power wireless communication channel(s) 158e with headset 161. Communication subsystem 111 communicates via second low power wireless communication channel(s) 158f, such as Bluetooth, with smart watch 162. In one or more particular embodiments, communication subsystem 111 communicates with other communication device(s) 163 via wireless link 158g to form an ad hoc network.
Data storage subsystem 113 of communication device 100 includes data storage device(s) 166. Controller 101 is communicatively connected, via system interlink 167, to data storage device(s) 166. Data storage subsystem 113 provides applications, program code, and stored data on nonvolatile storage that is accessible by controller 101. For example, data storage subsystem 113 can provide a selection of program code and applications such as antenna control application 115, location service applications 116, and other application(s) 117 that use communication services. These applications can be loaded into device memory 112 for execution by controller 101. In one or more embodiments, data storage device(s) 166 can include hard disk drives (HDDs), optical disk drives, and/or solid-state drives (SSDs), etc. Data storage subsystem 113 of communication device 100 can include removable storage device(s) (RSD(s)) 169, which is received in RSD interface 170. Controller 101 is communicatively connected to RSD 169, via system interlink 167 and RSD interface 170. In one or more embodiments, RSD 169 is a non-transitory computer program product or computer readable storage device. Controller 101 can access RSD 169 or data storage device(s) 166 to provision communication device 100 with program code, such as antenna control application 115 and other applications 117. When executed by controller 101, the program code causes or configures communication device 100 to provide the multi-transceiver operational functionality using configurable housing assembly 102 described herein.
Controller 101 includes processor subsystem 124, which includes one or more central processing units (CPUs), depicted as data processor 172. Processor subsystem 124 can include one or more digital signal processors 173 that are integrated with data processor 172 or are communicatively coupled to data processor 172, such as baseband processor 149 of communication module 140. Controller 101 can include one or more application processor(s) 174 to monitor sensors or controls such as housing position sensor 109 and antenna switch network 146. In one or embodiments that are not depicted, controller 101 can further include distributed processing and control components that are peripheral or remote to housing assembly 102 or grouped with other components, such as I/O subsystem 114. Data processor 172 is communicatively coupled, via system interlink 167, to device memory 112. In one or more embodiments, controller 101 of communication device 100 is communicatively coupled via system interlink 167 to communication subsystem 111, data storage subsystem 113, and input/output subsystem 114. System interlink 167 represents internal components that facilitate internal communication by way of one or more shared or dedicated internal communication links, such as internal serial or parallel buses. As utilized herein, the term “communicatively coupled” means that information signals are transmissible through various interconnections, including wired and/or wireless links, between the components. The interconnections between the components can be direct interconnections that include conductive transmission media or may be indirect interconnections that include one or more intermediate electrical components. Although certain direct interconnections (interlink 167) are illustrated in
Controller 101 manages, and in some instances directly controls, the various functions and/or operations of communication device 100. These functions and/or operations include, but are not limited to including, application data processing, communication with other communication devices, navigation tasks, image processing, and signal processing. In one or more alternate embodiments, communication device 100 may use hardware component equivalents for application data processing and signal processing. For example, communication device 100 may use special purpose hardware, dedicated processors, general purpose computers, microprocessor-based computers, micro-controllers, optical computers, analog computers, dedicated processors and/or dedicated hard-wired logic.
Within the description of the remaining figures, references to similar components presented in a previous figure are provided the same reference numbers across the different figures. Where the named component is presented with different features or functionality, a different reference numeral or a sub scripted reference numeral is provided (e.g., 100a in place of 100).
In
According to one aspect, housing assembly 102 includes a plurality of possible antenna mounting locations, illustrated as antenna mounting locations 201-208. First antenna mounting location 201 is a left section of distal side 106a of first housing portion 103a. Second antenna mounting location 202 is a left section of distal side 106b of second housing portion 103b. Third antenna mounting location 203 is a right section of distal side 106a of first housing portion 103a. Fourth antenna mounting location 204 is a right section of distal side 106b of second housing portion 103b. Fifth antenna mounting location 205 is on left lateral side 107a of first housing portion 103a. Sixth antenna mounting location 206 is on left lateral side 107b of second housing portion 103b. Seventh antenna mounting location 207 is on right lateral side 108a of first housing portion 103a. Eighth antenna mounting location 208 on right lateral side 108b of second housing portion 103b. While housing assembly 102 is in the closed position of
Second communication subsystem portion 302b includes antennas 137d-137f that support third and fourth single RF transceiver chains 304c-304d. Fourth antenna 137d is positioned at a second lateral section of distal side 106a of first housing portion 103a. Fifth antenna 137e is positioned at a second lateral section of distal side 106b of second housing portion 103b. Sixth antenna 137f is positioned at second lateral side 108a of first housing portion 103a. Second lateral side 108b of second housing portion 103b does not include an antenna. Third single RF transceiver chain 304c is communicatively connected to fourth antenna 137d via antenna matching network 148d. Fourth single RF transceiver chain 304d is communicatively connected by second antenna switch 146b to either of fifth antenna 137e via antenna matching network 148e or sixth antenna 137f via antenna matching network 148f. In one or more embodiments, second antenna switch 146b is a two pole, single throw switch. In response to receiving an open position signal from housing position sensor 109, application processor 174 configures second antenna switch 146b to communicatively connect fourth single RF transceiver chain 304d to fifth antenna 137e.
Method 600 includes communicating in one or more RF communication bands, via a first transceiver of an RF front end of the communication device using a first antenna of at least three antennas (block 602). Method 600 includes monitoring a housing position sensor within a housing assembly of a communication device (block 604). The housing position sensor detects: (i) when the housing assembly is in the closed position; and (ii) when the housing assembly is in an at least partially open position.
Method 600 includes determining whether the housing assembly is in the at least partially open position (decision block 606). In response to determining that the housing assembly is in the at least partially open position, method 600 includes configuring a first antenna switch in a first state to connect a second RF transceiver of the RF front end to the second antenna (block 608). In one or more embodiments, method 600 includes configuring the first antenna switch in the first state to further connect a first antenna impedance sensor to the third antenna (block 610). For example, the first antenna switch can be a two pole, two throw switch. Method 600 includes monitoring the first antenna impedance sensor that measures impedance of the third antenna (block 612). Method 600 includes determining whether the third antenna is blocked based on identifying a change greater than the threshold value in the impedance value measured by the second antenna impedance sensor (decision block 614). In response to determining that the third antenna is blocked, method 600 includes communicating via second transceiver (block 616). The controller can avoid using the third antenna that is closer to the first antenna than the second antenna. The controller can determine that blocking of the third antenna provides an indication to the controller that the first antenna could also be blocked. After block 616, method 600 returns to block 602. In response to determining that the third antenna is not blocked, method 600 includes communicating via both the first and the second transceivers (block 618). After block 618, method 600 returns to block 602.
Referring back to decision block 606, in response to determining that the housing assembly is not in the at least partially open position (i.e., the housing assembly is in the closed position), method 600 includes configuring the first antenna switch in a second state to connect the second RF transceiver of the RF front end to the third antenna (block 620). Method 600 includes detuning the second antenna using an antenna tuning network to preserve antenna radiated performance by the first antenna (block 622). In one or more embodiments, method 600 includes configuring the first antenna switch in the second state to further connect a first antenna impedance sensor to the second antenna (block 624). For example, the first antenna switch can be a two pole, two throw switch. Method 600 includes monitoring the first antenna impedance sensor that measures impedance of the second antenna (block 626). Method 600 includes determining whether the second antenna is blocked based on identifying a change greater than the threshold value in the impedance value measured by the second antenna impedance sensor (decision block 628). In response to determining that the second antenna is blocked, method 600 includes assigning communication workload to the second transceiver b (block 630). For example, the second antenna is close to the first antenna in the closed position. Thus, communication workload can be shifted to the third antenna, presuming that the first antenna is also blocked. After block 630, method 600 returns to block 602 (
In one or more embodiments, the communication device includes laterally symmetric portions of an antenna subsystem further including a fourth, a fifth, and a sixth antenna on an opposite lateral section to the first, second and third antennas. In one or more embodiments, the fourth, fifth and sixth antennas are configured in the same manner respectively as the first, the second, and the third antennas for use by a third and a fourth transceiver.
Aspects of the present innovation are described above with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the innovation. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
As will be appreciated by one skilled in the art, embodiments of the present innovation may be embodied as a system, device, and/or method. Accordingly, embodiments of the present innovation may take the form of an entirely hardware embodiment or an embodiment combining software and hardware embodiments that may all generally be referred to herein as a “circuit,” “module” or “system.”
While the innovation has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for elements thereof without departing from the scope of the innovation. In addition, many modifications may be made to adapt a particular system, device, or component thereof to the teachings of the innovation without departing from the essential scope thereof. Therefore, it is intended that the innovation not be limited to the particular embodiments disclosed for carrying out this innovation, but that the innovation will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the innovation. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present innovation has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the innovation in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the innovation. The embodiments were chosen and described in order to best explain the principles of the innovation and the practical application, and to enable others of ordinary skill in the art to understand the innovation for various embodiments with various modifications as are suited to the particular use contemplated.
