Patent Application
20160020509
Not Applicable
Not Applicable
1. Technical Field of the Invention
This invention relates generally to wireless communication systems and more particularly to antennas used in such systems.
2. Description of 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 to radio frequency identification (RFID) systems. Each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, radio frequency (RF) wireless communication systems may operate in accordance with one or more standards including, but not limited to, RFID, IEEE 802.11, Bluetooth, advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), WCDMA, local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), LTE, WiMAX, and/or variations thereof. As another example, infrared (IR) communication systems may operate in accordance with one or more standards including, but not limited to, IrDA (Infrared Data Association).
Depending on the type of RF wireless communication system, a wireless communication device, such as a cellular telephone, two-way radio, personal digital assistant (PDA), personal computer (PC), laptop computer, home entertainment equipment, RFID reader, RFID tag, 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 (e.g., one of the 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 (e.g., for cellular services) and/or an associated access point (e.g., 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 the public switch telephone network, via the Internet, and/or via some other wide area network.
For each RF wireless communication device to participate in wireless communications, it includes a built-in radio transceiver (i.e., receiver and transmitter) or is coupled to an associated radio transceiver (e.g., a station for in-home and/or in-building wireless communication networks, RF modem, etc.). As is known, the receiver is coupled to the antenna and includes a low noise amplifier, one or more intermediate frequency stages, a filtering stage, and a data recovery stage. The low noise amplifier receives inbound RF signals via the antenna and amplifies then. The one or more intermediate frequency stages mix the amplified RF signals with one or more local oscillations to convert the amplified RF signal into baseband signals or intermediate frequency (IF) signals. The filtering stage filters the baseband signals or the IF signals to attenuate unwanted out of band signals to produce filtered signals. The data recovery stage recovers raw data from the filtered signals in accordance with the particular wireless communication standard.
As is also known, the transmitter includes a data modulation stage, one or more intermediate frequency stages, and a power amplifier. The data modulation stage converts raw data into baseband signals in accordance with a 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 amplifies the RF signals prior to transmission via an antenna.
Since the wireless part of a wireless communication begins and ends with the antenna, a properly designed antenna structure is an important component of wireless communication devices. As is known, the antenna structure is designed to have a desired impedance (e.g., 50 Ohms) at an operating frequency, a desired bandwidth centered at the desired operating frequency, and a desired length (e.g., ¼ wavelength of the operating frequency for a monopole antenna). As is further known, the antenna structure may include a single monopole or dipole antenna, a diversity antenna structure, the same polarization, different polarization, and/or any number of other electro-magnetic properties.
One popular antenna structure for RF transceivers is a three-dimensional in-air helix antenna, which resembles an expanded spring. The in-air helix antenna provides a magnetic omni-directional monopole antenna. Other types of three-dimensional antennas include aperture antennas of a rectangular shape, horn shaped, etc.; three-dimensional dipole antennas having a conical shape, a cylinder shape, an elliptical shape, etc.; and reflector antennas having a plane reflector, a corner reflector, or a parabolic reflector. An issue with such three-dimensional antennas is that they cannot be implemented in the substantially two-dimensional space of a substrate such as an integrated circuit (IC) and/or on the printed circuit board (PCB) supporting the IC.
Two-dimensional antennas are known to include a meandering pattern or a micro strip configuration. For efficient antenna operation, the length of an antenna should be ¼ wavelength for a monopole antenna and ½ wavelength for a dipole antenna, where the wavelength (λ)=c/f, where c is the speed of light and f is frequency. For example, a ¼ wavelength antenna at 900 MHz has a total length of approximately 8.3 centimeters (i.e., 0.25*(3×108 m/s)/(900×106 c/s)=0.25*33 cm, where m/s is meters per second and c/s is cycles per second). As another example, a ¼ wavelength antenna at 2400 MHz has a total length of approximately 3.1 cm (i.e., 0.25*(3×108 m/s)/(2.4×109 c/s)=0.25*12.5 cm).
Regardless of whether a two-dimensional antenna is implemented on an IC and/or a PCB, the amount of area that it consumes is an issue. For example, a dipole antenna that uses Hilbert shapes operating in the 5.5 GHz frequency band requires each antenna element to be ¼ wavelength, which is 13.6 mm [“Compact 2D Hilbert Microstrip Resonators,” MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Vol. 48, No. 2, February 2006]. Each antenna element consumes approximately 3.633 mm2 (e.g., ½*(1.875 mm×3.875 mm)), which has a length-to-area ratio of 3.74:1 (e.g., 13.6:3.633). While this provides a relatively compact two-dimensional antenna, further reductions in consumed area are needed with little or no degradation in performance.
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 Invention, and the claims. Other features and advantages of the present invention will become apparent from the following detailed description of the invention made with reference to the accompanying drawings.
The device 10 may be any type of electronic equipment that includes integrated circuits. For example, but far from an exhaustive list, the device 10 may be a personal computer, a laptop computer, a hand held computer, a wireless local area network (WLAN) access point, a WLAN station, a cellular telephone, an audio entertainment device, a video entertainment device, a video game control and/or console, a radio, a cordless telephone, a cable set top box, a satellite receiver, network infrastructure equipment, a cellular telephone base station, and Bluetooth head set. Accordingly, the functional circuit 54-60 may include one or more of a WLAN baseband processing module, a WLAN RF transceiver, a cellular voice baseband processing module, a cellular voice RF transceiver, a cellular data baseband processing module, a cellular data RF transceiver, a local infrastructure communication (LIC) baseband processing module, a gateway processing module, a router processing module, a game controller circuit, a game console circuit, a microprocessor, a microcontroller, and memory.
In one embodiment, the dies 30-36 may be fabricated using complementary metal oxide (CMOS) technology and the package substrate may be a printed circuit board (PCB). In other embodiments, the dies 30-36 may be fabricated using Gallium-Arsenide technology, Silicon-Germanium technology, bi-polar, bi-CMOS, and/or any other type of IC fabrication technique. In such embodiments, the package substrate 22-28 may be a printed circuit board (PCB), a fiberglass board, a plastic board, and/or some other non-conductive material board. Note that if the antenna structure is on the die, the package substrate may simply function as a supporting structure for the die and contain little or no traces.
In an embodiment, the RF transceivers 46-52 provide local wireless communication (e.g., IC to IC communication) and/or remote wireless communications (e.g., to/from the device to another device). In this embodiment, when a functional circuit of one IC has information (e.g., data, operational instructions, files, etc.) to communication to another functional circuit of another IC or to another device, the RF transceiver of the first IC conveys the information via a wireless path to the RF transceiver of the second IC or to the other device. In this manner, some to all of the IC-to-IC communications may be done wirelessly.
In one embodiment, a baseband processing module of the first IC converts outbound data (e.g., data, operational instructions, files, etc.) into an outbound symbol stream. The conversion of outbound data into an outbound symbol stream may be done in accordance with one or more data modulation schemes, such as amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), amplitude shift keying (ASK), phase shift keying (PSK), quadrature PSK (QPSK), 8-PSK, frequency shift keying (FSK), minimum shift keying (MSK), Gaussian MSK (GMSK), quadrature amplitude modulation (QAM), a combination thereof, and/or alterations thereof. For example, the conversion of the outbound data into the outbound system stream may include one or more of scrambling, encoding, puncturing, interleaving, constellation mapping, modulation, frequency to time domain conversion, space-time block encoding, space-frequency block encoding, beamforming, and digital baseband to IF conversion.
The RF transceiver of the first IC converts the outbound symbol stream into an outbound RF signal. The antenna structure of the first IC is coupled to the RF transceiver and transmits the outbound RF signal, which has a carrier frequency within a frequency band (e.g., 900 MHz, 1800 MHz, 1900 MHz, 2.4 GHz, 5.5. GHz, 55 GHz to 64 GHz, etc.). Accordingly, the antenna structure includes electromagnetic properties to operate within the frequency band. For example, the length of the antenna structure may be ¼ or ½ wavelength, have a desired bandwidth, have a desired impedance, have a desired gain, etc.
For a local wireless communication, the antenna structure of the second IC receives the RF signal as an inbound RF signal and provides it to the RF transceiver of the second IC. The RF transceiver converts the inbound RF signal into an inbound symbol stream and provides the inbound symbol stream to a baseband processing module of the second IC. The baseband processing module of the second IC converts the inbound symbol stream into inbound data in accordance with one or more data modulation schemes, such as amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), amplitude shift keying (ASK), phase shift keying (PSK), quadrature PSK (QSK), 8-PSK, frequency shift keying (FSK), minimum shift keying (MSK), Gaussian MSK (GMSK), quadrature amplitude modulation (QAM), a combination thereof, and/or alterations thereof. For example, the conversion of the inbound system stream into the inbound data may include one or more of descrambling, decoding, depuncturing, deinterleaving, constellation demapping, demodulation, time to frequency domain conversion, space-time block decoding, space-frequency block decoding, de-beamforming, and IF to digital baseband conversion. Note that the baseband processing modules of the first and second ICs may be on same die as RF transceivers or on a different die within the respective IC.
In other embodiments, each IC 14-20 may include a plurality of RF transceivers and antenna structures on-die, on-package substrate, and/or on the substrate 12 to support multiple simultaneous RF communications using one or more of frequency offset, phase offset, wave-guides (e.g., use waveguides to contain a majority of the RF energy), frequency reuse patterns, frequency division multiplexing, time division multiplexing, null-peak multiple path fading (e.g., ICs in nulls to attenuate signal strength and ICs in peaks to accentuate signal strength), frequency hopping, spread spectrum, space-time offsets, and space-frequency offsets. Note that the device 10 is shown to only include four ICs 14-20 for ease of illustrate, but may include more or less that four ICs in practical implementations.
The transmission line 70, which may be a pair of microstrip lines on the die 30-36, the package substrate 22-28, and/or on the device substrate 12 (individually, collectively or in combination may provide the substrate for the antenna apparatus), is electrically coupled to the antenna structure 38-44 and electromagnetically coupled to the impedance matching circuit 74 by first and second conductors. In one embodiment, the electromagnetic coupling of the first conductor to a first line of the transmission line 70 produces a first transformer and the electromagnetic coupling of the second conductor to a second line of the transmission line 70 produces a second transformer.
The impedance matching circuit 74, which may include one or more of an adjustable inductor circuit, an adjustable capacitor circuit, an adjustable resistor circuit, an inductor, a capacitor, and a resistor, in combination with the transmission line 70 and the first and second transformers establish the impedance for matching that of the antenna structure 38-44.
The switching circuit 72 includes one or more switches, transistors, tri-state buffers, and tri-state drivers, to couple the impedance matching circuit 74 to the RF transceiver 46-52 (from
The ground plane 80 has a surface area larger than the surface area of the antenna structure 38-44. The ground plane 80, from a first axial perspective, is substantially parallel to the antenna structure 38-44 and, from a second axial perspective, is substantially co-located to the antenna structure 38-44.
As a specific example, the bandwidth of an antenna having a length of ½ wavelength or less is primarily dictated by the antenna's quality factor (Q), which may be mathematically expressed as shown in Eq. 1 where v0 is the resonant frequency, 2δv is the difference in frequency between the two half-power points (i.e., the bandwidth).
Equation 2 provides a basic quality factor equation for the antenna structure, where R is the resistance of the antenna structure, L is the inductance of the antenna structure, and C is the capacitor of the antenna structure.
As such, by adjusting the resistance, inductance, and/or capacitance of an antenna structure, the bandwidth can be controlled. For instance, the smaller the quality factor, the narrower the bandwidth. Note that the capacitance is primarily established by the length of, and the distance between, the lines of the transmission line 70, the distance between the elements of the antenna 90, and any added capacitance to the antenna structure. Further note that the lines of the transmission line 70 and those of the antenna structure 38-44 may be on the same layer of an IC, package substrate, and/or the device substrate 12 and/or on different layers.
In this embodiment, with the elements 90 on different layers, the electromagnetic coupling between them via the coupling circuits 92 is different than when the elements are on the same layer as shown in
In an embodiment of this illustration, the adjustable ground plane 80 may include a plurality of ground planes and a ground plane selection circuit. The plurality of ground planes is on one or more layers of the substrate.
In an embodiment of this illustration, the adjustable ground plane 80 includes a plurality of ground plane elements and a ground plane coupling circuit. The ground plane coupling circuit is operable to couple at least one of the plurality of ground plane elements into the ground plane 80 in accordance with a ground plane characteristic signal, which may be provided by one or more of the functional circuits.
The MPC metal trace 112 may be configured to provide one or more of a variety of antenna configurations. For example, the MPC metal trace 112 may have a length of ¼ wavelength to provide a monopole antenna. As another example, the MPC metal trace 112 may be configured to provide a dipole antenna. In this example, the MPC metal trace 112 would include two sections, each ¼ wavelength in length. As yet another example, the MPC metal trace 112 may be configure to provide a microstrip patch antenna.
In this embodiment, the plurality of metal traces 112 may be coupled to form an antenna array; may be coupled to form a multiple input multiple output (MIMO) antenna; may be coupled to form a microstrip patch antenna; may be coupled to form a dipole antenna; or may be coupled to form a monopole antenna.
The first metal trace 130 has a first modified Polya curve shape (e.g., has a first order value, a first shaping factor value, and a first line width or trace width value) that is confined in a first polygonal shape (e.g., a triangular shape, a rectangle, a pentagon, hexagon, an octagon, etc.). As shown, the first metal trace 130 is on a first layer 82 of the substrate. While not specifically shown in this illustration, a first terminal is coupled to the first metal trace. Examples of such a configuration are provided in previous figures.
The second metal trace 132 has a second modified Polya curve shape (e.g., has a second order value, a second shaping factor value, and a second line width or trace width value) that is confined in a second polygonal shape (e.g., a triangular shape, a rectangle, a pentagon, hexagon, an octagon, etc.). As is also shown, the second metal trace 132 is on the second layer 84 of the substrate. Note that the first and second modified Polya curves may be the same (e.g., have the same order, shaping factor, and trace width) or different modified Polya curves (e.g., have one or differences in the order, shaping factor, and/or trace width). Further note that a second terminal is coupled to the second metal trace 132.
In an embodiment, the first and second metals trace 130, 132 may be configured to provide a microstrip patch antenna; a dipole antenna; or a monopole antenna. In another embodiment, the first metal trace 130 may be configured to provide a first microstrip patch antenna and the second metal trace 132 may be configured to provide a second microstrip patch antenna. In another embodiment, the first metal trace 130 may be configured to provide a dipole antenna and the second metal trace 132 may be configured to provide a second dipole antenna. In another embodiment, the first metal trace 130 may be configured to provide a first monopole antenna and the second metal trace 132 configured to provide a second monopole antenna. In one or more of the embodiments, the first and/or second metal trace 130, 132 may include an extension metal trace to tune antenna properties of the antenna structure.
In an embodiment, the plurality of metal trace segments of the first and/or second metal traces 130, 132 may be coupled to form one or more antenna arrays. In another embodiment, the plurality of metal trace segments of the first and/or second metal traces 130, 132 may be coupled to form one or more multiple input multiple output (MIMO) antennas. In another embodiment, the plurality of metal trace segments of the first and/or second metal traces 130, 132 may be coupled to form one or more microstrip patch antennas. In another embodiment, the plurality of metal trace segments of the first and/or second metal traces 130, 132 may be coupled to form one or more dipole antennas. In another embodiment, the plurality of metal trace segments of the first and/or second metal traces 130, 132 may be coupled to form one or more monopole antennas.
The properties of the antenna apparatus (e.g., center frequency, bandwidth, gain, quality factor, etc.) may be tuned by having an extension metal trace coupled to the metal trace 112. The properties may be further tuned based on the order, the line width, and/or the shaping factor of the modified Polya curve.
In another embodiment, the antenna apparatus includes a plurality of metal traces 112; each having the modified Polya curve shape that is confined in the triangular shape and a length-to-area ratio that is approximately in the range of 4-to-1 to 7-to-1. In this embodiment, the plurality of metal traces are arranged to form a polygonal shape (e.g., a rectangle, a pentagon, a hexagon, an octagon, etc.) to form an antenna array, a MIMO antenna, a microstrip patch antenna, a monopole antenna, or a dipole antenna. Note that the plurality of metal traces 112 is coupled to a plurality of terminals 114.
The antenna apparatus may further include more antenna components on additional layers and may include further vias 146. For example, a third antenna component, which may have a third pattern of an arbitrary geometric shape that are the same or different as those of the first and/or second antenna components, is on a third layer of the IC, of the IC substrate, and/or of the PCB. The first antenna component 142 is coupled to the second antenna element using one or more vias 146 and the second antenna component 144 may be coupled to the third antenna component using one or more vias 146. The combined length of the antenna structure (e.g., a sum of the individual lengths of the first and second antenna components 142, 144, and the third if included) at least partially determines the operating characteristics (e.g., frequency, bandwidth, quality factor, impedance, etc.) of the antenna structure. Such an antenna structure provides a small footprint antenna that may be used in numerous RF and/or MMW communication devices.
The embodiments of three-dimensional antennas various embodiments of
A second antenna structure of the plurality of antenna structures includes third and fourth antenna components and a via. The third antenna component is on a third substrate layer and the fourth antenna component is on a fourth substrate layer. The via couples the third antenna component to the fourth antenna component, wherein the third antenna overlaps, from a radial perspective, the fourth antenna component by a second angle of overlap.
In an example, the antenna array is implemented on a substrate. The substrate includes at least two layers, where a first layer of the substrate constitutes the first and third substrate layers and a second layer of the substrate constitutes the second and fourth substrate layers. As such, the antenna structures of the antenna array are implemented on two (or more) layers of the same substrate. For instance, if one or more of the antenna structures includes a third antenna element (or more), then more than two layers of the substrate would be used.
In another example, the antenna array is implemented on multiple substrates. A first substrate supports the first antenna structure and a second substrate supports the second antenna structure. As such, the first antenna structure is implemented on two or more layers of the first substrate (e.g., an IC die or an IC package substrate) and the second antenna structure is implemented on two more layers of the second substrate (e.g., an IC die, an IC package substrate, a PCB, etc.). Note that each antenna structure of the array may operate in substantially the same frequency band, in different frequency bands, and/or a combination thereof.
As may be used herein, the terms “substantially” and “approximately” provides an industry-accepted tolerance for its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to fifty 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. Such relativity between items ranges from a difference of a few percent to magnitude differences. As may also be used herein, the term(s) “operably coupled to”, “coupled to”, and/or “coupling” includes direct coupling between items and/or indirect coupling between items via an intervening item (e.g., an item includes, but is not limited to, a component, an element, a circuit, and/or a module) where, for indirect coupling, the intervening item does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As may further be used herein, inferred coupling (i.e., where one element is coupled to another element by inference) includes direct and indirect coupling between two items in the same manner as “coupled to”. As may even further be used herein, the term “operable to” or “operably coupled to” indicates that an item includes one or more of power connections, input(s), output(s), etc., to perform, when activated, one or more its corresponding functions and may further include inferred coupling to one or more other items. As may still further be used herein, the term “associated with”, includes direct and/or indirect coupling of separate items and/or one item being embedded within another item. As may be used herein, the term “compares favorably”, indicates that a comparison between two or more items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than signal 2, a favorable comparison may be achieved when the magnitude of signal 1 is greater than that of signal 2 or when the magnitude of signal 2 is less than that of signal 1.
The present invention has also been described above with the aid of method steps illustrating the performance of specified functions and relationships thereof. The boundaries and sequence of these functional building blocks and method steps have been arbitrarily defined herein for convenience of description. Alternate boundaries and sequences can be defined so long as the specified functions and relationships are appropriately performed. Any such alternate boundaries or sequences are thus within the scope and spirit of the claimed invention.
The present invention has been described above with the aid of functional building blocks illustrating the performance of certain significant functions. The boundaries of these functional building blocks have been arbitrarily defined for convenience of description. Alternate boundaries could be defined as long as the certain significant functions are appropriately performed. Similarly, flow diagram blocks may also have been arbitrarily defined herein to illustrate certain significant functionality. To the extent used, the flow diagram block boundaries and sequence could have been defined otherwise and still perform the certain significant functionality. Such alternate definitions of both functional building blocks and flow diagram blocks and sequences are thus within the scope and spirit of the claimed invention. One of average skill in the art will also recognize that the functional building blocks, and other illustrative blocks, modules and components herein, can be implemented as illustrated or by discrete components, application specific integrated circuits, processors executing appropriate software and the like or any combination thereof.
The present U.S. Utility patent application claims priority pursuant to 35 U.S.C. §121 as a divisional of U.S. Utility application Ser. No. 12/985,300, entitled “THREE-DIMENSIONAL ANTENNA STRUCTURE”, filed Jan. 5, 2011, which claims priority pursuant to 35 U.S.C. §119(e) to U.S. Provisional Application No. 61/293,303, entitled “THREE-DIMENSIONAL ANTENNA STRUCTURE”, filed Jan. 8, 2010, both of which are hereby incorporated herein by reference in their entirety and made part of the present U.S. Utility patent application for all purposes. U.S. Utility application Ser. No. 12/985,300 claims priority pursuant to 35 U.S.C. §120 as a continuation-in-part of U.S. Utility application Ser. No. 12/642,360, entitled “ANTENNA STRUCTURES AND APPLICATIONS THEREOF”, filed Dec. 18, 2009, issued as U.S. Pat. No. 8,570,222 on Oct. 29, 2013, which claims priority pursuant to 35 U.S.C. §119(e) to U.S. Provisional Application No. 61/145,049, entitled “ANTENNA STRUCTURES AND APPLICATIONS THEREOF”, filed Jan. 15, 2009, both of which are hereby incorporated herein by reference in their entirety and made part of the present U.S. Utility patent application for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 61145049 | Jan 2009 | US | |
| 61293303 | Jan 2010 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12985300 | Jan 2011 | US |
| Child | 14734017 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12642360 | Dec 2009 | US |
| Child | 12985300 | US |
