1. Technical Field
The present disclosure described herein relates generally to wireless communications and more particularly to multi-antenna configurations in a wireless communication device.
2. Description of Related Art
Communication systems are known to support wireless and wireline communications between wireless and/or wireline 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, wireless communication systems may operate in accordance with one or more standards including, but not limited to, 3GPP (3rd Generation Partnership Project), 4GPP (4th Generation Partnership Project), LTE (long term evolution), LTE Advanced, RFID, IEEE 802.11, Bluetooth, AMPS (advanced mobile phone services), digital AMPS, GSM (global system for mobile communications), CDMA (code division multiple access), LMDS (local multi-point distribution systems), MMDS (multi-channel-multi-point distribution systems), and/or variations thereof.
Depending on the type of wireless communication system, a wireless communication device, such as a cellular telephone, smartphone, two-way radio, tablet, 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 each 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 transceiver is coupled to one or more antennas, for example, multiple-input, multiple-output (MIMO) and may include one or more low noise amplifiers, one or more intermediate frequency stages, a filtering stage, and a data recovery stage.
As is also known, diversity antenna structures include two or more antennas that are spaced at one-quarter wavelength intervals. Each antenna receives the same RF signals and the received signal strength of each antenna is measured. The antenna having the strongest, or most consistently strong, signal strength is selected as the RF input for the receiver. This can be a dynamic process that changes as the receiver is moved.
As illustrated, host device 101 includes processing module 103, memory 104, radio interface 105, input interface 107 and output interface 106. The processing module 103 and memory 104 execute instructions typically performed by the host device. For example, for a cellular telephone host device, the processing module 103 performs the corresponding communication functions in accordance with a particular cellular telephone standard.
Radio interface 105 allows data to be received from and sent to radio 102. For data received from radio 102 (e.g., inbound data), radio interface 105 provides data to processing module 103 for further processing and/or routing to output interface 106. Output interface 106 provides connectivity to an output display device such as a display, monitor, speakers, et cetera such that the received data may be displayed. Radio interface 105 also provides data from processing module 103 to radio 102. Processing module 103 may receive outbound data from an input device such as a keyboard, keypad, microphone, et cetera via input interface 107 or generate the data itself. For data received via input interface 107, the processing module 103 may perform a corresponding host function on the data and/or route it to the radio 102 via radio interface 105.
Radio 102 includes a host interface 108, memory 109, a receiver path, a transmit path, a local oscillation module 110, and an antenna structure 119, which may be on-chip, off-chip, or a combination thereof. The receive path includes a baseband processing module 113 and a plurality of RF receivers 121-123. The transmit path includes baseband processing module 113 and a plurality of radio frequency (RF) transmitters 116-118. Baseband processing module 113, in combination with operational instructions stored in memory 109 and/or internally operational instructions, executes digital receiver functions and digital transmitter functions, respectively. The digital receiver functions include, but are not limited to, digital intermediate frequency to baseband conversion, demodulation, constellation demapping, depuncturing, decoding, de-interleaving, fast Fourier transform, cyclic prefix removal, space and time decoding, and/or descrambling. The digital transmitter functions include, but are not limited to, scrambling, encoding, puncturing, interleaving, constellation mapping, modulation, inverse fast Fourier transform, cyclic prefix addition, space and time encoding, and digital baseband to IF conversion. Processing module 103 and/or baseband processing module 113 may be implemented using one or more processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions. Memory 109 may be a single memory device or a plurality of memory devices. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, and/or any device that stores digital information. Note that when processing module 103 and/or baseband processing module 113 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory storing the corresponding operational instructions is embedded with the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry.
In operation, radio 102 receives outbound data 112 from host device 101 via host interface 108. Baseband processing module 113 receives outbound data 112 and, based on a mode selection signal 114, produces one or more outbound symbol streams 115. Mode selection signal 114 will indicate a particular mode of operation that is compliant with one or more specific modes of the various IEEE 802.11, 3G, 4G, LTE, RFID, etc., standards. For example, the mode selection signal 114 may indicate a frequency band of 2.4 GHz, a channel bandwidth of 20 or 22 MHz and a maximum bit rate of 54 megabits-per-second. In this general category, the mode selection signal will further indicate a particular rate ranging from 1 megabit-per-second to 54 megabits-per-second. In addition, the mode selection signal will indicate a particular type of modulation, which includes, but is not limited to, Barker Code Modulation, BPSK, QPSK, CCK, 16 QAM and/or 64 QAM. Mode selection signal 114 may also include a code rate, a number of coded bits per subcarrier (NBPSC), coded bits per OFDM symbol (NCBPS), and/or data bits per OFDM symbol (NDBPS). Mode selection signal 114 may also indicate a particular channelization for the corresponding mode that provides a channel number and corresponding center frequency. Mode selection signal 114 may further indicate a power spectral density mask value and a number of antennas to be initially used for a MIMO communication.
Baseband processing module 113, based on the mode selection signal 114 produces one or more outbound symbol streams 115 from outbound data 112. For example, if the mode selection signal 114 indicates that a single transmit antenna is being utilized for the particular mode that has been selected, the baseband processing module 113 will produce a single outbound symbol stream (one of outbound symbol streams 115). Alternatively, if the mode selection signal 114 indicates 2, 3 or 4 antennas, the baseband processing module 113 will produce 2, 3 or 4 outbound symbol streams 115 from the outbound data 112.
Depending on the number of outbound symbol streams 115 produced by the baseband processing module 113, a corresponding number of the RF transmitters 116-118 will be enabled to convert the outbound symbol streams 115 into outbound RF signals 125. The RF transmitters 116-118 provide the outbound RF signals 125 to a corresponding antenna of the antenna structure 119.
When radio 102 is in the receive mode, the antenna structure 119 receives one or more inbound RF signals 120 and provides them to one or more RF receivers 121-123. The RF receivers 121-123 convert the one or more inbound RF signals 120 into a corresponding number of inbound symbol streams 124. The number of inbound symbol streams 124 will correspond to the particular mode in which the data was received. The baseband processing module 113 converts the inbound symbol streams 124 into inbound data 111, which is provided to the host device 101 via the host interface 108.
The wireless communication device 100 of
Antenna structure 119, in one or more embodiments, includes multiple antenna designs (e.g., MIMO) for both transmission and reception. While the number of antennas used to transmit/receive may be variable, the directionality (direction to receive or transmit signals) may also vary. To affect directionality, antennas may be polarized. In RF communications, polarization is a property of waves that can oscillate with more than one orientation.
To increase reception/transmission, matching an angle of, for example, of a specific oriented received signal will provide a stronger signal. However, cross-polarization of signals between the transmitter and the receiver limit the received signal power in wireless communications links with a limited number of signal pathways between the transmitter and receiver. Cross-polarization is radiation orthogonal to the desired polarization. For instance, the cross-polarization of a vertically polarized antenna is the horizontally polarized fields.
Transceiver 401 includes a Tx pathway and an Rx pathway that are connected to (paired) polarized antennas 402 (Pol. 1) and 403 (Pol. 2) through DPDT switch 404. DPDT switch 404 includes 4 quarter wavelength transmission lines 405A, 405B, 405C and 405D (i.e., 2 for each pathway). In the Rx pathway (shown as activated), RF signals are received by either Pol. 1 antenna 402 or Pol. 2 antenna 403 based on the position of switches 406, 407, 408 and 409. For the RF signal to be received through Pol. 1 antenna 402 switch 406 is open and switch 408 is open allowing the RF signal to be received through quarter wavelength transmission line 405C. However, the DPDT configuration as provided includes a large area and contains signal cross-overs that increase signal loss and reduce isolation between antenna ports.
Standard DPDT switches based on quarter wavelength transmissions lines include signal cross-overs that lead to higher signal loss, lower signal isolation and larger area requirements. In one or more embodiments of the technology described herein, a staggered configuration of receivers, transmitters and the antenna ports of a multi-antenna system are provided that avoid signal cross-overs.
In the Rx pathway (shown as activated), RF signals are received by transceiver 501 by either Pol. 1 antenna 503C or Pol. 2 antenna 503B based on the position the antenna polarization selection switch. DPDT switch 504 includes Tx/Rx selection switches 506A, 506B, 506C and 506D and antenna polarization selection switches 506E, 506F, 506G, 506H and 506I for controlling the path of the received RF signal in the communication pathway. For example, in a Rx pathway, the RF signal is received through Pol. 1 antennas 503C and 503E, and switches 506C, 506E, 506G and 506I are open allowing the RF signal to be received by the receiver pathway. Tx/Rx selection switches 506A through 506D are connected to antenna polarization selection switches 506E through 506I by quarter wavelength transmission lines 505A, 505B, 505C, 505D, 505E, 505F, 505G and 505H. The staggered configuration as illustrated in
This staggered configuration provides for the Tx/Rx selection switches or the antenna polarization switches to select the nearest (or adjacent) options without having to cross-over other signal paths in a multi-antenna system. For example, In Rx mode as shown in
Transceivers 601B and 601C are connected in a series with transceiver 601A, where transceiver 601B is connected to antennas 602B (Pol. 1) and 603B (Pol. 2) through DPDT switch 604B (including Tx/Rx selection switch 605B and antenna polarization selection switch 606B). Transceiver 601C is connected to antennas 602C (Pol. 1) and 603C (Pol. 2) through DPDT switch 604C (including Tx/Rx selection switch 605C and antenna polarization selection switch 606C). Although shown as a multi-antenna system having three transceivers, multi-antenna systems consisting of four or more transceivers are within scope of the technology described herein.
In one embodiment, Pol. 1 antennas are used in Rx mode when transceivers 701A, 701B and 701C are connected to antennas 707B (Pol. 1), 707D (Pol. 1) and 707F (Pol. 1) through Tx/Rx selection switches 703B, 703D and 703F and antenna polarization selection 704B, 704D and 704F that connect through spiral inductors 705D, 705H and 705L.
Quarter wavelength transmission lines 808A, 809A and 814A and Tx/Rx selection switch 810A and antenna polarization selection switch 811A are opened, preventing the operation of the corresponding pathways. Horizontal polarized antenna 813A and antenna polarization selection switch 812A are shared between transceiver 801A and the next transceiver in the cyclic configuration.
In an alternative embodiment, the staggered configuration is terminated using one additional Tx or Rx at each terminal end. For example, as shown in
In other embodiments, termination is provided by not having one antenna available in each polarization for Rx. In an alternative embodiment, termination is provided by removing two antennas in the lower priority Rx polarization. Referring again to
In one embodiment of the technology described herein, a staggered DPDT multi-antenna communications system includes deep-Nwell N-type metal-oxide-semiconductor (NMOS) switches with positive body bias.
To reduce circuit space requirements in one or more embodiments of the technology described herein, quarter wavelength transmission lines are replaced with spiral inductors. When the staggered DPDT multi-antenna communications system is implemented using spiral inductors, the link performance is improved (e.g., +2.3 dB). Additionally, the output compression of the transmitter is also improved by reduction of the large-signal load provided to the power amplifier (PA).
In one or more embodiments the technology described herein the wireless connection can communicate in accordance with a wireless network protocol such as Wi-Fi, WiHD, NGMS, IEEE 802.11a, ac, b, g, n, or other 802.11 standard protocol, Bluetooth™, LTE, Ultra-Wideband (UWB), WIMAX, or other wireless network protocol, a wireless telephony data/voice protocol such as Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), Enhanced Data Rates for Global Evolution (EDGE), Personal Communication Services (PCS), or other mobile wireless protocol or other wireless communication protocol, either standard or proprietary. Further, the wireless communication path can include separate transmit and receive paths that use separate carrier frequencies and/or separate frequency channels. Alternatively, a single frequency or frequency channel can be used to bi-directionally communicate data to and from the mobile communications device.
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) “configured to”, “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 an example of 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 “configured to”, “operable to”, “coupled 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.
As may also be used herein, the terms “processing module”, “processing circuit”, “processor”, and/or “processing unit” may be a single processing device or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on hard coding of the circuitry and/or operational instructions. The processing module, module, processing circuit, and/or processing unit may be, or further include, memory and/or an integrated memory element, which may be a single memory device, a plurality of memory devices, and/or embedded circuitry of another processing module, module, processing circuit, and/or processing unit. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information. Note that if the processing module, module, processing circuit, and/or processing unit includes more than one processing device, the processing devices may be centrally located (e.g., directly coupled together via a wired and/or wireless bus structure) or may be distributedly located (e.g., cloud computing via indirect coupling via a local area network and/or a wide area network). Further note that if the processing module, module, processing circuit, and/or processing unit implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory and/or memory element storing the corresponding operational instructions may be embedded within, or external to, the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry. Still further note that, the memory element may store, and the processing module, module, processing circuit, and/or processing unit executes, hard coded and/or operational instructions corresponding to at least some of the steps and/or functions illustrated in one or more of the Figures. Such a memory device or memory element can be included in an article of manufacture.
One or more embodiments of an invention have 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 claims. Further, 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 one or more embodiments are used herein to illustrate one or more aspects, one or more features, one or more concepts, and/or one or more examples of the invention. A physical embodiment of an apparatus, an article of manufacture, a machine, and/or of a process may include one or more of the aspects, features, concepts, examples, etc. described with reference to one or more of the embodiments discussed herein. Further, from figure to figure, the embodiments may incorporate the same or similarly named functions, steps, modules, etc. that may use the same or different reference numbers and, as such, the functions, steps, modules, etc. may be the same or similar functions, steps, modules, etc. or different ones.
Unless specifically stated to the contra, signals to, from, and/or between elements in a figure of any of the figures presented herein may be analog or digital, continuous time or discrete time, and single-ended or differential. For instance, if a signal path is shown as a single-ended path, it also represents a differential signal path. Similarly, if a signal path is shown as a differential path, it also represents a single-ended signal path. While one or more particular architectures are described herein, other architectures can likewise be implemented that use one or more data buses not expressly shown, direct connectivity between elements, and/or indirect coupling between other elements as recognized by one of average skill in the art.
The term “module” is used in the description of one or more of the embodiments. A module includes a processing module, a processor, a functional block, hardware, and/or memory that stores operational instructions for performing one or more functions as may be described herein. Note that, if the module is implemented via hardware, the hardware may operate independently and/or in conjunction with software and/or firmware. As also used herein, a module may contain one or more sub-modules, each of which may be one or more modules.
While particular combinations of various functions and features of the one or more embodiments have been expressly described herein, other combinations of these features and functions are likewise possible. The present disclosure of an invention is not limited by the particular examples disclosed herein and expressly incorporates these other combinations.
The present U.S. Utility Patent Application claims priority pursuant to 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 61/899,392, entitled “Staggered Network Based Transmit/Receive Switch with Antenna Polarization Diversity, filed Nov. 4, 2013, which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes.
Number | Date | Country | |
---|---|---|---|
61899392 | Nov 2013 | US |