Method and apparatus for focused data communications

Information

  • Patent Grant
  • 12052083
  • Patent Number
    12,052,083
  • Date Filed
    Tuesday, September 5, 2023
    a year ago
  • Date Issued
    Tuesday, July 30, 2024
    5 months ago
  • Inventors
  • Original Assignees
  • Examiners
    • Nguyen; Phuongchau Ba
    Agents
    • Volpe Koenig
  • CPC
  • Field of Search
    • CPC
    • H04B7/0695
    • H04B7/0617
    • H04B7/0619
    • H04B7/0691
    • H04W4/029
    • H04W4/02
    • H04W72/005
    • H04W4/06
    • H04W8/02
    • H04L12/189
    • H04L12/185
  • International Classifications
    • H04H20/71
    • H04B7/06
    • H04W4/029
    • Disclaimer
      This patent is subject to a terminal disclaimer.
      Term Extension
      0
Abstract
A method and apparatus for focused communication is disclosed. The method includes a base transmitter array in communication with at least one client device at the same frequency. The base transmitter array provides a focused data communication to the client device.
Description
FIELD OF INVENTION

The present invention relates generally to data communications.


BACKGROUND

As the world becomes more and more dependent on access to data from mobile devices, there is an increasing need to provide data services to clients requesting them. Cellular systems, global positioning systems (GPS) and wireless communication systems, (e.g., IEEE 802 systems), are faced with limitations regarding, for example, bandwidth, range, and capacity. Some solutions to this are to add infrastructure and/or to utilize pointed range techniques. However, these methods can be costly and ineffective.


Thus, a method and apparatus for focusing data communications is desired.


SUMMARY

A method and apparatus for focused communication is disclosed. The method includes a base transmitter array in communication with at least one client device. The base transmitter array provides a focused data communication to the client device.


These and other features of the invention will become readily apparent upon further review of the following specification and drawings.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is an example system diagram of a focused data communications system including a client device and a base transmitter array;



FIG. 2 is another example system diagram of a focused data communications system including a plurality of client devices;



FIG. 3 is another example system diagram of a focused data communications system including a moving client device;



FIG. 4 is a flow diagram of an example method of providing focused data communications;



FIG. 5 is an example functional block diagram of an antenna element processor in accordance with an embodiment;



FIG. 6 is an example functional block diagram of an array controller in accordance with an embodiment;



FIG. 7 is an example functional block diagram of a client device in accordance with an embodiment;



FIGS. 8A-8F are example system diagrams of a focused data communications base transmitter array during detection of a new client device;



FIG. 9 shows an example array coverage of a focused data communications system; and



FIGS. 10A-10C are example diagrams of directivity and location embodiments of a focused communications system.





Similar reference characters denote corresponding features consistently throughout the attached drawings.


DETAILED DESCRIPTION


FIG. 1 is an example system diagram of a focused data communications system 100 including a client device 110 and a base transmitter array 120. The base transmitter array 120 includes a plurality of antennas 121. It should be noted that, although nineteen antennas 121 are depicted in the example base transmitter array 120, any number of antennas may be utilized. The client 110, (denoted C1), is in wireless communication with the antennas 121 of the base transmitter array 120. Each antenna 121 receives the communication from the client device 110 at a different time offset and transmits data to the client device 110 utilizing the time offset in the reverse order to the transmission time offset received from the client device 110 such that when the data transmission signals from each antenna 121 are summed at the client device 110, a clear signal is received. For example, the path length per antenna 121 may be p(n). The time of the path then may be given by the equation:

t(n)=p(n)/c,  Equation (1)

where c=the speed of light.


In order for the data transmission signals from each antenna element 121 to arrive at the client device 110 at the same time, each antenna element 121 starts its transmission at:

time=max(t(n))−t(n).  Equation (2)



FIG. 2 is another example system diagram of a focused data communications system 200 including a plurality of client devices 110. In system 200, each client device 110, (denoted C1, C2, and C3), is in wireless communication with each antenna element 121 of the base transmitter 120. In this case, multiple communication links are created between the base transmitter 120 and each client device 110.


Since each signal to client C1, C2, and C3 is separated, the client devices 110 may share the same frequency or channel, thus allowing an increase in the utilization of each frequency band or communication channel. Additionally, the signal of each client device 110 should be below, or much lower than, the noise level of the signal intended to another client device 110. For example, signals not intended for C1 cancel one another, resulting in a clear transmission of the signal intended for C1 at client device C1.


In order to transmit simultaneous signals to multiple clients 110 on the same frequency, each antenna element 121 utilizes the time offset received from each client 110 relative to every other antenna element 121 in the base transmitter array 120. Accordingly, each antenna element 121 may then sum the encoded signals and transmit a juxtaposed sum of all the client 110 signals to the clients 110, resulting in separate spatially isolated data communication signals that the intended client 110 may receive and decode clearly. For example, at an intended focus location, the signals (each having a strength “s”), add up linearly, causing a linear increase in the client device's 110 antenna, whereby the total signal is N times s. However, at non-intended focus locations, the signals are received at haphazard times without a cohesive phase, resulting in a signal that has a strength of: (s0+s1+s2+s3+s4+s5+s6+ . . . +sN)/N, which is much weaker than the intended focus signal.


Also, since the same, or a single, frequency may be shared and utilized to transmit data from the base transmitter array 120 to multiple clients 110, it is therefore possible to expand the capacity of the data communication systems, (e.g., 100, 200 and 300). For example, by utilizing multiple frequencies, where groups of client devices 110 share a first frequency, groups of client devices 110 share a second frequency, and so on, many more client devices 110 may be provided services by the base transmitter array 120.



FIG. 3 is another example system diagram of a focused data communications system 300 including a moving client device 110, denoted as C2. In this scenario, the client device C2 is moving from a first position (POS1) to a second position (POS2) in the direction of the arrow, while maintaining wireless communication with each of the antenna elements 121 of the base transmitter array 120. Each antenna element 121 is recalibrated during every signal reception to account for the change in time offset received from client device C2.



FIG. 4 is a flow diagram of an example method 400 of providing focused data communications. For purposes of example, method 400 may be applied to any of the above described systems 100, 200, and 300, as well as any other data communications system. In step 410, the base transmitter array 120 receives an encoded signal from at least one client device 110. For example, in the system depicted in FIG. 1, the base transmitter array 120 receives a communication signal from client device C1. In FIG. 2, the base transmitter array 120 receives multiple communication signals from client devices C1, C2, and C3. In FIG. 3, the base transmitter array 120 is shown receiving a communication signal from client device C2.


Each antenna element 121 of the base transmitter array 120 receives the data communications from the at least one client device 110 with a different time offset than every other antenna element 121. For example, referring back to FIG. 1, antenna element 1211 receives the data communication from client device C1 with a different offset than antenna element 121n. Accordingly, each antenna element 121 of the base transmitter 120 determines an input time offset from the at least one client device 110 (step 420) with respect to every other antenna element 121.


The offset determination may be performed by summing of the totality of the antennas of the antenna elements 121. In this manner, each antenna element 121 is comparing itself to the consensus, and when an antenna is getting away from the consensus, it starts to get back in line with a new offset, which it discovers by testing its output against the consensus, or testing its modified time offset consensus against the consensus without the modification, and choosing whether to keep the modification or stay the same. This may be performed by the antenna elements 121 whether the client device 110 is in motion or not.


Once the time offset is computed, each antenna element 121 of the base transmitter 120 is tuned based on the time offset for each client device 110 (step 430). For example, each antenna element 121 may time offset its transmission signal to the client device 110 in the reverse order of the received time offset from the client device 110.


In step 440, each antenna element 121 of the base transmitter 120 transmits data to the at least one client device 110 based upon the determined time offset at that antenna element.


Since the client devices 110 may be in motion, a determination is made as to whether the at least one client device 110 has moved (step 450). For example, in FIG. 3, client C2 is shown moving from POS1 to POS2. In this case, each antenna element 121 is recalibrated and retuned (step 460) to account for the movement of the client device 110. This may be accomplished by comparing each antenna element's time shifted signal against a consolidated signal, whereby if the time shifted signal is not in synch with the consolidated signal, it is adjusted to match the consolidated signal, and is communicated to each antenna element 121 to update a table entry with respect to that client device 110.



FIG. 5 is an example functional block diagram of an antenna element processor 500 in accordance with an embodiment. The antenna element processor 500 includes a plurality of client carrier components 510, a plurality of message encoding components 520, a network switch 530, a summer 540, an incoming signal analog to digital (A/D) encoder 550, a phase and time detection component 560, a send/receive multiplexer/demultiplexer (MUX/DEMUX) 570, and an antenna 580. Client information for each client device 110, (e.g., client ID, phase position, and time offset), is stored in a table 590 utilized by the antenna element processor 500.


Data enters on an input line to the network switch 530, while carrier and time synch information are input into the client carrier component 510 and phase and time detection component 560. The carrier information may be common signal carrier information shared with all antenna elements 121, such as a lower frequency for use by a phase locked loop (PLL) to target the frequency of any desired channel. The time synch signal may be a clock that allows resolution of events to a sub-wave level, (e.g., 10 ns for a 2.4 GHz signal, or 4 ns for a 900 MHz signal).


The network switch 530 outputs a message signal to the message encoding components 520, which also receive inputs from respective client carrier components 510. The network switch 530 also provides the client information table 590 information to the client carrier components 510 and message encoding components 520. The summer 540 receives the signals from the message encoding components 520 along with the appropriate time offset for each client device 110 and outputs an outgoing signal to the MUX/DEMUX 570 for transmission by the antenna 580. If the input received by the summer 540 is a digital signal, the summer may be a digital signal adder and convert the summation to analogue, while if the input to the summer 540 is an analog signal, the summer 540 performs the summation in the analog domain.


The MUX/DEMUX 570 also receives incoming transmissions from the antenna 580 and forwards the incoming signal sans the outgoing signal, to the incoming signal A/D encoder 550 and phase and time detection component 560. The MUX/DEMUX 570 may be utilized to operate to allow multiple client devices 110 to transmit to the antenna element 121, while transmitting data from the antenna element 121 to other client devices 110.


The incoming signal A/D encoder 550 outputs a digital signal to the network switch 530, and the phase and time detection component outputs a signal to the incoming signal A/D encoder 550. The phase and time detection component 560 may detect or establish new client devices 110, for example utilizing an encoded beacon signal from a client device 110.



FIG. 6 is an example functional block diagram of an array controller 600 in accordance with an embodiment. The array controller 600 may be utilized to coordinate the functioning of all of the antenna elements 121. The array controller 600 includes a plurality of conceptual components 610, a digital to digital signal decoder (D/D) 620, a system clock 630, a network switch 640, a data network switch 650, and a plurality of connectors 660.


In operation, where each antenna element 121 has established its phase and time offsets necessary to send out a signal, each data packet for transmission is tagged with the client identification so that it may be encoded with the appropriate phase and time offsets.


The array controller 600 receives signals from a client device 110 in the conceptual component 610 for a particular client device 110. This signal may be received indirectly via the A/D encoder 550 of each antenna element processor 500. The signal from each antenna element 121 may then be added to the signals from all other antenna elements 121 utilizing “reverse timing” of the client device 110 time offset used to transmit. The reverse timing may be computed in accordance with the following equation:

Reverse Timing=(MaxClientTimeOffset)−ClientTimeOffset,  Equation (3)

where the reverse timing is effectively a number between 0 and the ClientTimeOffset for each client, and MaxTimeOffset is the difference in time from the earliest antenna element 121 receiving a signal to the latest antenna element 121 receiving the same signal.


Since each client device 110 is silent for some of the time, there may be little crosstalk between signals and the data lines may be silent. Where more than one client device 110 is in the same location for the most part, (e.g., “hot spot”), where the time offsets are so similar to one another that their signals are received superimposed, it may be difficult to differentiate between one client device 110 and another. In these cases, time division multiple access (TDMA) and/or code division multiple access (CDMA) transmission techniques may be utilized. A client device 110 may also deactivate collision detection mechanisms in order to transmit to the base transmitter 120 without waiting for other client devices 110 to cease their transmissions, in order to enable full two-way bandwidth capabilities with each client device 110.


The network switch 640 receives data, (e.g., data packets from/to client devices 110), from a thick data pipe from an external central network and communicates data back and forth to each conceptual component 610, which includes a message decoder 611, a summer 612 and a plurality of time shifters 613. Data proceeds to the antenna elements 121 from the conceptual components 610 via the D/D 620, data network switch 650 and the connector 660 for a respective antenna element 121. Additionally, the system clock 630 provides the carrier and time synch signals for each antenna element 121. Outgoing data to clients is provided by the network switch 640 to the data network switch 650.



FIG. 7 is an example functional block diagram of an example client device 110 in accordance with an embodiment. The client device 110 includes a processor 115, a transmitter 116 in communication with the processor 115, a receiver 117 in communication with the processor 115, an antenna 118 in communication with the transmitter 116 and the receiver 117, and a memory 119 in communication with the processor 115 in order to facilitate wireless transmission and reception. The processor 115 may be configured to process data communications for transmission and reception to and from the base transmitter array 120.



FIGS. 8A-8F are example system diagrams of a focused data communications base transmitter array 820 during detection of a new client device 110. For purposes of example, the base transmitter array 820 is substantially similar to the base transmitter array 120, and although nineteen antenna elements 821 are shown, it should be understood that more or less antenna elements may be utilized. Additionally, it should be noted that antenna elements 821 are substantially similar to antenna elements 121.


When the base transmitter array 821 is operational, it may detect new clients within its service domain and establish time offsets for communication. When a client device 110 is powered on, it attempts to communicate with the base transmitter array 820. Accordingly, the base transmitter array 820 may tune specific antenna elements 821 to specific directions. For example, in FIG. 8A, antenna elements 9, 11 and 12 are tuned to a first direction. In FIG. 8B, antenna elements 5, 15, and 19 are tuned to a second direction. In FIG. 8C, antenna elements 6, 14, and 17 are tuned to a third direction. In FIG. 8D, antenna elements 8, 9, and 11 are tuned to a fourth direction. In FIG. 8E, antenna elements 1, 5, and 15 are tuned to a fifth direction. In FIG. 8F, antenna elements 3, 6, and 14 are tuned to a sixth direction. The tuning may be accomplished in a soft manner, such as by dedicated circuitry such as the conceptual component 610 describe above.


In the layout shown in FIGS. 8A-8F, each reception lobe of the base transmitter array 820 may have a width of 75 degrees, allowing overlap and full coverage around the array. However, it should be noted that any subdivision of 360 degrees may be utilized to form the reception lobes that make up the set of tuned directions.



FIG. 9 shows an example array coverage of a focused data communications system 900 tuned in accordance with the antenna elements 821 in FIGS. 8A-8F. The base transmitter array 920, which is substantially similar to the base transmitter arrays 120 and 820, includes a coverage area 930. A plurality of coverage lobes 940 include a plurality of overlap areas 941. Accordingly, a new client device 110 within the coverage area 930 is detected by the base transmitter array 920.


Since the directional lobes are monitoring for new client devices 110 not yet known, once a new client device 110 is detected, the remainder of the antenna elements 821 may be provided with information to quickly correct their respective time and phase offsets so that the newly detected client devices 110 receive their focused spatially directed data signal.


Due to the signals being highly focused, battery life of the client device 110 may be increased as the client device 110 may utilize less power for communication with the base transmitter array 120/420/820/920. Additionally, the coverage area 930 may be greater than in a conventional communication system for the same power, since focused signals may travel farther, and since the array is able to tune to a particular client device 110, as opposed to sending signal power out in multiple directions.



FIGS. 10A-10C are example diagrams of directivity and location embodiments of a focused communications system 1000. For example, in FIG. 10A, the system includes a base transmitter array 1020, which is substantially similar to the base transmitter arrays 120, 420, 820 and 920. As conventional data communication arrays include antennas directed generally downward, only a client device 110 at ground level G may experience quality data communications. Accordingly, a client device 110 at position T at the top floor of a tall building B, or a client device 110 on an airplane A, may not receive quality data communications.


By utilizing a focused data communication system, such as using the base transmitter 1020, (shown on a conventional cellular tower), high quality signals may be provided to client devices 110 at locations G, B, or A.



FIGS. 10B and 10C depict the focused data communication system 1000 in an embodiment that may be utilized for location based services, similar to GPS or navigation services. In the example shown in FIGS. 10B and 10C, a client device 110 at location L, shown adjacent to building B, may be located using the base transmitter array 1020. By analyzing the time offsets at each antenna element (not shown) of the base transmitter array 1020, it can be determined the angle of altitude of location L with respect to the height H of the base transmitter array 1020. Similarly, an azimuth angle θ can be determined by knowledge of the direction of the location L with respect to North in relation to the base transmitter array 1020. Additionally, since the distance d may be determined by the configuration of the base transmitter array 1020, location services may be provided to the client device 110 at location L. Effectively, by examining the time delays at the base transmitter array 1020, the direction of the client may be determined. However, since the base transmitter array 1020 has volumetric size, multiple determined directions may be traced from the edges of the volume to determine where they converge at, which may provide the actual location (direction+distance).


The methods and devices described above may operate at the physical communication layer stack. However, it should be noted that any stack may be utilized to carry out functionality as needed for any of the methods and devices described above.


It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. For example, the client device described above may refer to a cellular phone, PDA, or any other wireless device that may be utilized for data communication. Additionally, for example, the size of the base transmitter array may be on the order of the (number of clients)2.5, however any size may be utilized. Additionally, although the client device 110 is shown, for purposes of example, as having only a single antenna, it should be noted that client devices may include more than one antenna.


Also, it should be noted that the base transmitter array may be a large set of antennas configured in a three-dimensional (3D) arrangement, where each antenna is capable transmitting one or more data encoded signals, whereby the transmitted signal is the sum of the encoded signals to be transmitted. As described above, each signal may be added with a specific time offset that is different for each antenna element. One example arrangement to arrange the antenna elements of the base transmitter array is to utilize the example of 3D quasi-crystal arrangement.


Additionally, although the features and elements of the present application are described in the example embodiments in particular combinations, each feature or element can be used alone (without the other features and elements of the example embodiments) or in various combinations with or without other features and elements of the present application.

Claims
  • 1. A wireless communication system comprising: an array controller configured to: receive a first signal from a client device via a plurality of antenna elements;determine a respective input timing offset for each element of the plurality of antenna elements for the first signal to provide a plurality of respective input timing offsets, wherein the determination comprises comparing each respective input timing offset of the plurality of respective input timing offsets with a consensus across the plurality of respective input timing offsets of the plurality of antenna elements, anddetermine a first location of a client device in three-dimensional space based on the plurality of respective input timing offsets; andthe plurality of antenna elements communicatively coupled to the array controller, the plurality of antenna elements being configured to: transmit, as controlled by on the array controller, an electromagnetic wave to the client device using the plurality of respective input timing offsets, andgenerate, as controlled by on the array controller, constructive interference of the electromagnetic wave at the first location.
  • 2. The wireless communication system of claim 1, wherein the plurality of respective input timing offsets are further determined by testing a modified offset consensus against the consensus.
  • 3. The wireless communication system of claim 2, wherein the wireless communication system is configured to select to keep the modified offset consensus as the consensus or discard the modified offset consensus.
  • 4. The wireless communication system of claim 1, wherein the array controller is configured to determine a motion vector for the client device based upon the plurality of respective input timing offsets.
  • 5. The wireless communication system of claim 1, wherein the electromagnetic wave provides power to the client device.
  • 6. The wireless communication system of claim 1, wherein the array controller is configured to demultiplex the first signal into multiple data signals.
  • 7. The wireless communication system of claim 6, wherein the array controller is configured to generate a output signal responsive to the first signal.
  • 8. The wireless communication system of claim 7, wherein the array controller is configured to multiplex a plurality of data signals in to the output signal.
  • 9. A wireless communication device comprising: an array controller configured to: receive a first signal from a client device via a plurality of antenna elements;determine a respective input timing offset for each element of the plurality of antenna elements for the first signal to provide a plurality of respective input timing offsets, wherein the determination comprises comparing each respective input timing offset of the plurality of respective input timing offsets with a consensus across the plurality of respective input timing offsets of the plurality of antenna elements, anddetermine a first location of a client device in three-dimensional space based on the plurality of respective input timing offsets; andthe plurality of antenna elements communicatively coupled to the array controller, the plurality of antenna elements being configured to: transmit, as controlled by on the array controller, an electromagnetic wave to the client device using the plurality of respective input timing offsets, andgenerate, as controlled by on the array controller, constructive interference of the electromagnetic wave at the first location.
  • 10. The wireless communication device of claim 9, wherein the plurality of respective input timing offsets are further determined by testing a modified offset consensus against the consensus.
  • 11. The wireless communication device of claim 10, wherein the wireless communication device is configured to select to keep the modified offset consensus as the consensus or discard the modified offset consensus.
  • 12. The wireless communication device of claim 9, wherein the array controller is configured to determine a motion vector for the client device based upon the plurality of respective input timing offsets.
  • 13. The wireless communication device of claim 9, wherein the electromagnetic wave provides power to the client device.
  • 14. The wireless communication device of claim 9, wherein the array controller is configured to demultiplex the first signal into multiple data signals.
  • 15. The wireless communication device of claim 14, wherein the array controller is configured to generate a output signal responsive to the first signal.
  • 16. The wireless communication device of claim 15, wherein the array controller is configured to multiplex a plurality of data signals in to the output signal.
CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No. 17/671,212, filed Feb. 14, 2022, which is a continuation of U.S. application Ser. No. 16/725,215, filed Dec. 23, 2019, which issued as U.S. Pat. No. 11,265,064 on Mar. 1, 2022, which is a continuation of U.S. application Ser. No. 15/649,187, filed Jul. 13, 2017, which issued as U.S. Pat. No. 10,523,301 on Dec. 31, 2019, which is a continuation of U.S. application Ser. No. 15/153,361, filed May 12, 2016, which issued as U.S. Pat. No. 9,736,815 on Aug. 15, 2017, which is a continuation of U.S. application Ser. No. 14/186,344 filed Feb. 21, 2014, which issued as U.S. Pat. No. 9,351,281 on May 24, 2016, which claims the benefit of U.S. Provisional Patent Application No. 61/768,004, filed Feb. 22, 2013, the contents of all are incorporated herein by reference as if fully set forth.

US Referenced Citations (46)
Number Name Date Kind
3314067 Rutz Apr 1967 A
5729825 Kostreski et al. Mar 1998 A
6167272 Hellstern Dec 2000 A
6510172 Miller Jan 2003 B1
6741587 Holma et al. May 2004 B2
7288918 Di Stefano Oct 2007 B2
7406055 Taira Jul 2008 B2
7599420 Forenza et al. Oct 2009 B2
7990840 Laroia et al. Aug 2011 B2
8032134 Tung Oct 2011 B2
8135423 Fuijita et al. Mar 2012 B2
8310201 Wright Nov 2012 B1
9350442 Ohm et al. May 2016 B2
9351281 Zeine May 2016 B2
9736315 Pulhug Aug 2017 B2
9736815 Zeine Aug 2017 B2
9941754 Leabman Apr 2018 B2
10128931 Rothaar Nov 2018 B2
10523301 Zeine Dec 2019 B2
10884094 Johnson Jan 2021 B2
11265064 Zeine Mar 2022 B2
20020085627 Younis Jul 2002 A1
20020137547 Judson Sep 2002 A1
20030117320 Kim et al. Jun 2003 A1
20040023649 Bing et al. Feb 2004 A1
20040152415 Anagnos Aug 2004 A1
20040203905 Cuffaro Oct 2004 A1
20040213187 Fujil Oct 2004 A1
20070037528 Doan et al. Feb 2007 A1
20070140177 Li et al. Jun 2007 A1
20080214128 Lim et al. Sep 2008 A1
20080285631 Shattil Nov 2008 A1
20080298494 Richardson Dec 2008 A1
20100112936 Friman et al. May 2010 A1
20100172421 Okamura Jul 2010 A1
20110032149 Leabman Feb 2011 A1
20110250928 Schlub et al. Oct 2011 A1
20120142280 Banu et al. Jun 2012 A1
20120281783 Cheng et al. Nov 2012 A1
20130039342 Kazmi Feb 2013 A1
20140078973 Kazmi et al. Mar 2014 A1
20140114635 Sato et al. Apr 2014 A1
20140192915 Mundarath et al. Jul 2014 A1
20180062715 Li Mar 2018 A1
20190369263 Kreeger Dec 2019 A1
20220173518 Stokes Jun 2022 A1
Foreign Referenced Citations (33)
Number Date Country
1252189 May 2000 CN
1545770 Nov 2004 CN
1653828 Aug 2005 CN
1746699 Mar 2006 CN
1802797 Jul 2006 CN
101056451 Oct 2007 CN
101056451 Oct 2007 CN
101171765 Apr 2008 CN
100435492 Nov 2008 CN
101317336 Dec 2008 CN
101861718 Oct 2013 CN
102204120 Jul 2014 CN
107181518 Sep 2017 CN
111190184 May 2020 CN
1922824 May 2008 EP
1992077 Nov 2008 EP
2269408 Jan 2011 EP
06-303172 Oct 1994 JP
10-070502 Mar 1998 JP
2005-140639 Jun 2005 JP
2005-159504 Jun 2005 JP
2006-166321 Jun 2006 JP
2006-246633 Sep 2006 JP
2013-047942 Mar 2013 JP
2009-0110593 Oct 2009 KR
200910811 Mar 2009 TW
9708849 Mar 1997 WO
2005053182 Jun 2005 WO
2007021891 Feb 2007 WO
2007084717 Dec 2007 WO
2009025501 Feb 2009 WO
2009111597 Dec 2009 WO
2013006462 Jan 2013 WO
Non-Patent Literature Citations (1)
Entry
Ye, “Study on the Application of the SDMA Theory in MIMO,” Chinese Master's Thesis (Jul. 31, 2012).
Related Publications (1)
Number Date Country
20230421234 A1 Dec 2023 US
Provisional Applications (1)
Number Date Country
61768004 Feb 2013 US
Continuations (5)
Number Date Country
Parent 17671212 Feb 2022 US
Child 18461124 US
Parent 16725215 Dec 2019 US
Child 17671212 US
Parent 15649187 Jul 2017 US
Child 16725215 US
Parent 15153361 May 2016 US
Child 15649187 US
Parent 14186344 Feb 2014 US
Child 15153361 US