• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    A wireless communication system includes a private LTE base station, a commercial carrier LTE base station, and a mobile wireless communications device. The mobile wireless communications device includes an LTE transceiver, a memory, and a controller coupled to the LTE transceiver and the memory. The controller stores an assigned AC value in the memory based upon a priority of use characteristic value, stores a random AC value in the memory, and determines whether access is available to the private LTE base station or the commercial carrier LTE base station. When the private LTE base station is available for access, a connection is made based upon the assigned AC value and a private LTE barring value received from the private LTE base station. When the commercial carrier LTE base station is available for access, a connection is made based upon the random AC value and a commercial carrier barring value.
    公开号:AU2013217617A1
    申请号:U2013217617
    申请日:2013-01-30
    公开日:2014-06-19
    发明作者:Gregory Newell Henderson；Reid Henry Johnson
    申请人:Harris Corp；
    IPC主号:H04W48-02
    专利说明:
    WO 2013/119426 PCT/US2013/023699 WIRELESS COMMUNICATION SYSTEM HAVING ASSIGNED ACCESS CLASSES AND RELATED METHODS Field of the Invention 5 The present invention relates to the field of wireless communications, and, more particularly, to a long term evolution wireless communication system and related methods. Background of the Invention 10 A typical wireless communications system comprises a plurality of wireless communications devices exchanging data with each other. In some wireless communications systems, for example, infrastructure networks, the system may further comprise a wireless base station for managing communications between the wireless communications devices. In other words, each intra-system communication 15 would be exchanged via the wireless base station. In other wireless communications systems, for example, mesh networks and ad hoc wireless networks, the wireless base station may be omitted, i.e., the wireless communications devices may communicate directly with each other. The wireless communications devices may communicate with each 20 other based upon a wireless communications protocol. The 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) wireless communications protocol is a robust technology aimed at providing metropolitan area networks, as disclosed in the 3GPP TS 22.011 V8.9.0 (2009-09) Technical Specification, which is hereby incorporated by reference in its entirety. In particular, the LTE wireless 25 protocol is commonly referred to as the fourth generation cellular protocol. The LTE wireless communications protocol may provide for: increased bandwidth, low latency, and increased signal penetration. Moreover, the LTE wireless communications protocol provides an entirely packet switched protocol for both voice and data, and a simplified infrastructure that is easily integrated into legacy 30 systems. -1- WO 2013/119426 PCT/US2013/023699 One potential drawback to the LTE wireless communications protocol may comprise sub-par performance in network sectors that are experiencing high user density, for example, during large events, such as sports events at large capacity stadiums. During these situations, the network throughput may be reduced 5 significantly, effectively rendering the wireless communication system inoperative. One approach to this drawback is included in the LTE wireless communications protocol, this approach comprising the barring factor feature. In the LTE wireless communications protocol, each mobile wireless communications device has an access class associated with it, the access classes including 0-15. In the LTE 10 wireless communication system, access classes 11-15 are reserved for special users, i.e., Class 15 -PLMN Staff; Class 14 - Emergency Services; Class 13 - Public Utilities (e.g., water/gas suppliers); Class 12 - Security Services; and Class 11 PLMN Use. When a wireless communications device connects to a wireless 15 network, the device is randomly assigned a class from 0-9. During situations where the LTE wireless communication system may need to throttle usage, the network operator may access the barring factor feature. When the wireless communications device first connects to the wireless communication system, the device receives the standing barring rate (when the base station is operating in barring mode) and the 20 device generates a random number. If the random number is less than the barring rate, the device continues to connect to the network. Otherwise, the device terminates the connection process to the LTE wireless communication system. A drawback to this approach is that since the mobile wireless communications device is barred based upon the randomly generated number, the barring rate is consequently applied 25 randomly without any consideration to the actual priority of the user. Another approach to priority in an LTE wireless communication system is disclosed in U.S. Patent Application Publication No. 2008/0200146 to Wang et al. Wang et al. uses the 11-15 access classes to provide priority similar to that of the typical LTE wireless communication system with special provisioning to 30 make emergency calls. -2- WO 2013/119426 PCT/US2013/023699 Summary of the Invention In view of the foregoing background, it is therefore an object of the present invention to provide an LTE wireless communication system that can address high use applications. 5 This and other objects, features, and advantages in accordance with the present invention are provided by an LTE wireless communication system comprising a private LTE base station, a commercial carrier LTE base station, and a mobile wireless communications device comprising an LTE transceiver, a memory, and a controller coupled to the LTE transceiver and the memory. The controller is 10 configured to store an assigned access class (AC) value in the memory based upon a priority of use characteristic value, store a random AC value in the memory, and determine whether access is available to the private LTE base station or the commercial carrier LTE base station. When the private LTE base station is available for access, then the wireless communication device will connect thereto based upon 15 the assigned AC value and a private LTE barring value received from the private LTE base station, and when the commercial carrier LTE base station is available for access, then connect thereto based upon the random AC value and a commercial carrier barring value received from the commercial carrier LTE base station. Advantageously, the mobile wireless communications device may operate in both 20 standard LTE wireless communication systems and in privatized special priority LTE communication systems. More specifically, the controller may be configured to generate a comparative barring rate based upon one of the assigned AC value and the random AC value, and compare the comparative barring rate with one of the private LTE 25 barring value and the commercial carrier barring value. The controller may be configured to stop connecting to the private LTE base station when the comparative barring rate is greater than or equal to the respective private LTE barring value. The controller may be further configured to stop connecting to the commercial carrier LTE base station when the comparative barring rate is greater than or equal to the 30 commercial carrier barring value. The controller may be configured to restart -3- WO 2013/119426 PCT/US2013/023699 connecting to the private LTE base station or the commercial carrier LTE base station after a barring time value has expired. Another aspect is directed to a method of operating an LTE mobile wireless communications device. The method includes storing an assigned AC value 5 in a memory of the LTE mobile wireless communication device based upon a priority of use characteristic value, storing a random AC value in the memory, and determining whether access is available to a private LTE base station or a commercial carrier LTE base station. The method also includes when the private LTE base station is available for access, then connecting thereto based upon the assigned AC value and 10 a private LTE barring value received from the private LTE base station, and when the commercial carrier LTE base station is available for access, then connecting thereto based upon the random AC value and a commercial carrier barring value received from the commercial carrier LTE base station. 15 Brief Description of the Drawings FIG. 1 is a schematic diagram of an LTE wireless communication system, according to the present invention. FIG. 2 is a flowchart illustrating operation of a mobile wireless communications device from the system of FIG. 1. 20 FIG. 3 is a more detailed flowchart illustrating operation of the mobile wireless communications device from the system of FIG. 1. FIG. 4 is a schematic diagram of prioritized ACs in the LTE wireless communication system of FIG. 1. 25 Detailed Description of the Preferred Embodiments The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. 30 Rather, these embodiments are provided so that this disclosure will be thorough and -4- WO 2013/119426 PCT/US2013/023699 complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. Referring initially to FIG. 1, an LTE wireless communication system 10 according to the present invention is now described. The LTE wireless 5 communication system 10 includes a private LTE base station 11 (FIG. 2: Public Safety PLMN), and a commercial carrier LTE base station 12. The commercial carrier LTE base station 12 is part of a commercial carrier cellular network, such as a Global System for Mobile Communications (GSM) or a code division multiple access (CDMA) cellular network (e.g., as provided by the Verizon Wireless or ATT Wireless 10 networks). The LTE wireless communication system 10 includes a mobile wireless communications device 13 comprising an LTE transceiver 15, an antenna 17 coupled to the LTE transceiver, a memory 14, and a controller 16 coupled to the LTE transceiver and the memory. For example, the controller 16 may comprise an 15 integrated circuit (IC) microprocessor, such as a dual core Tegra processor, as available from the NVIDIA Corporation of Santa Clara, CA, or may comprise a software module. Referring additionally to FIGS. 2-3 and flowcharts 80, 50 therein, a method of operating the mobile wireless communications device 13 is now described 20 (Blocks 81, 51). The controller 16 is configured to store an assigned AC value in the memory 14 based upon a priority of use characteristic value (Block 83). In particular, the assigned AC value utilizes the typical random ACs of LTE, i.e., AC values 0-9. Advantageously, while typical LTE systems place all public safety devices into AC 14 (Emergency Services), the mobile wireless communications device 13 is able to 25 leverage the already existing ACs 0-9 to provide the desired granularity in the prioritization. For example, the memory 14 may comprise a portion of a subscriber identification module (SIM) card, and the assigned AC value may be stored therein. The assigned AC value is for use in cooperation with the private LTE base station 11, 30 which is part of a private cellular communication network, such as a public safety -5- WO 2013/119426 PCT/US2013/023699 communication network or a government metropolitan area network, for example. The controller 16 is configured to store the priority of use characteristic value comprising at least one of a first responder user value or a maintenance user value. In short, the priority of use characteristic value ranks the relative importance of the 5 mobile wireless communications device 13 user to the private cellular communication network's operator. In one exemplary embodiment, the first responder user would have a greater priority than a typical maintenance user. The assigned AC value may be programmed into the memory 14 of the mobile wireless communications device 13 via multiple methods. One such method 10 may comprise the private cellular communication network's operator pre programming the assigned AC value into the mobile wireless communications device 13 before issuing the equipment to the user. In another embodiment, the user may subsequently program the assigned AC value into the memory 14 or change the pre programmed existing value. 15 For operation on the commercial carrier LTE base station 12, the controller 16 determines and stores a random AC value in the memory 14 (Block 85). In one embodiment, the controller 16 performs a random process to determine the random AC value, and in another embodiment, the commercial carrier LTE base station 12 provides such value, which is received via the LTE transceiver 15. 20 During operation, the mobile wireless communications device 13 travels through varying geographical areas that may or may not be within the network coverage of the commercial carrier LTE base station 12 and the private LTE base station 11. As an initial matter, the controller 16 determines whether it can camp (connect) onto either the private LTE base station 11 or the commercial carrier LTE 25 base station 12 (Blocks 87, 53). In other words, the controller 16 is configured to determine whether access is available to the private LTE base station 11 or the commercial carrier LTE base station 12. The controller 16 determines this availability of coverage by downloading a received network identification value (e.g., Public Land Mobile Network (PLMN) identification number) from either the private 30 LTE base station 11 or the commercial carrier LTE base station 12 (Block 55) (e.g., in -6- WO 2013/119426 PCT/US2013/023699 the illustrated embodiment, labeled broadcasted information elements). When either the private LTE base station 11 or the commercial carrier LTE base station 12 is available, as part of the initial cell provisioning process, the mobile wireless communications device 13 determines whether the network operator has engaged the 5 restricted access mode, i.e., utilization of the barring feature (Block 57). When the private LTE base station 11 is available for access, the controller 16 is configured to then connect thereto based upon the assigned AC value and a private LTE barring value received from the private LTE base station (Blocks 89, 59). The operator of the private LTE wireless communication system determines 10 whether to access the barring feature of LTE and selectively sets the private LTE barring value depending on usage dynamics. In some embodiments, the private LTE base station 11 is configured to set the private LTE barring value based upon a location of the private LTE base station. For example, if an emergency situation has occurred in a section of a city, the operator of the private LTE base station 11 may 15 lower the private LTE barring value transmitted to devices in the area of the emergency, thereby assuring that high priority users, such as first responders and law enforcement, may reliably use the private LTE base station. When the commercial carrier LTE base station 12 is available for access, the controller 16 is configured to then connect thereto based upon the random 20 AC value and a commercial carrier barring value received from the commercial carrier LTE base station (Block 91). Again, the commercial carrier makes the decision as to whether to utilize the barring feature of LTE. Advantageously, the mobile wireless communications device 13 operates typically during the connection process to the commercial carrier LTE base station 12, but utilizes a special priority 25 connection procedure when connecting to the private LTE base station 11 (Block 93). More specifically, and depending on which base station is available for access, the controller 16 is configured to generate a comparative barring rate based upon one of the assigned AC value (private LTE base station 11) and the random AC value (commercial carrier LTE base station 12). For example, the controller 16 30 illustratively divides either the assigned AC value or the random AC value by 10. -7- WO 2013/119426 PCT/US2013/023699 The controller 16 is configured to then compare the comparative barring rate with one of the private LTE barring value and the commercial carrier barring value (depending on which base station the mobile wireless communications device 13 is trying to connect to) (Blocks 61, 63). 5 Regardless of which base station the mobile wireless communications device 13 is trying to connect with, the controller 16 is configured to stop connecting to either the private LTE base station 11 or the commercial carrier LTE base station 12 when the comparative barring rate is greater than or equal to the respective private LTE barring value or the commercial carrier barring value. In other words, the 10 mobile wireless communications device 13 is barred from connecting to the respective base station. At Block 65, the controller 16 checks whether the AC value of the mobile wireless communications device 13 is in barred list. If the mobile wireless communications device 13 is barred, the controller 16 is configured to restart connecting to the private LTE base station 11 or the commercial carrier LTE base 15 station 12 after a barring time value has expired (Block 67). In the alternative, the mobile wireless communications device 13 may enter into the cell re-selection procedure, i.e., the controller 16 looks for other base stations to connect to (Block 69). The controller 16 is configured to continue connecting to the private LTE base station 11 or the commercial carrier LTE base station 12 when the 20 comparative barring rate is less than the respective private LTE barring value and the commercial carrier barring value (Blocks 71, 73, 75). In other words, the mobile wireless communications device 13 user's AC value has not been barred. In applications where the mobile wireless communications device 13 has access to multiple LTE base stations. In particular, the controller 16 of the mobile 25 wireless communications device 13 may be configured to, when both the private LTE base station 11 and the commercial carrier LTE base station 12 are available for access, then connect to a base station based upon a preferred received network identification value. For example, the controller 16 can store a preferred PLMN ID and connect to the base station associated with the same. In the case of a private user, 30 the mobile wireless communications device 13 would be configured to prefer the -8- WO 2013/119426 PCT/US2013/023699 private PLMN ID LTE base station 11 when in coverage of both. In the case where the controller 16 is barred from the private LTE base station 11, but had commercial coverage, it would connect to the commercial LTE base station 12. Advantageously, the mobile wireless communications device 13 is able 5 to operate with either the private LTE base station 11 or the commercial carrier LTE base station 12 with little modification to the typical network infrastructure. Also, the network operator of the private LTE base station 11 may adjust the private LTE barring rate on a site-to-site basis, providing enhanced control to network usage. Additionally, the mobile wireless communications device 13 appears to operate 10 typically to the network infrastructure, thereby maintaining adherence to LTE standards. Another aspect is directed to a method of operating an LTE mobile wireless communications device 13. The method includes storing an assigned AC value in a memory 14 of the LTE mobile wireless communication device 13 based 15 upon a priority of use characteristic value, storing a random AC value in the memory, and determining whether access is available to a private LTE base station 11 or a commercial carrier LTE base station 12. The method also includes when the private LTE base station 11 is available for access, then connecting thereto based upon the assigned AC value and a private LTE barring value received from the private LTE 20 base station, and when the commercial carrier LTE base station 12 is available for access, then connecting thereto based upon the random AC value and a commercial carrier barring value received from the commercial carrier LTE base station. Referring now to FIG. 4, a diagram 95 illustrates an example embodiment of the prioritized ACs from the LTE wireless communication system 10. 25 In particular, ACs 11-15 have typical assignments based upon the LTE wireless communications protocol. The random classes of 0-9 have been reassigned to provide a detailed and tiered AC arrangement. In particular, ACO is assigned to first responders, giving them the highest priority; AC 1 is assigned to law enforcement; AC2 is assigned to emergency medical services; AC3 is assigned to municipal 30 command and control; AC4 is assigned to fire prevention; AC5 is assigned to hospital -9- WO 2013/119426 PCT/US2013/023699 staff; AC6 is not assigned and left open for future expansion; and AC7-9 are assigned to varying levels of public utility workers. -10-
    权利要求:
    Claims (10)
    [1] 1. A long term evolution (LTE) wireless communication system comprising: 5 a private LTE base station; a commercial carrier LTE base station; and a mobile wireless communications device comprising an LTE transceiver, a memory, and a controller coupled to said LTE transceiver and said memory and configured to 10 store an assigned access class (AC) value in said memory based upon a priority of use characteristic value, store a random AC value in said memory, determine whether access is available to said private LTE base station or said commercial carrier LTE base station, 15 when said private LTE base station is available for access, then connect thereto based upon the assigned AC value and a private LTE barring value received from said private LTE base station, and when said commercial carrier LTE base station is 20 available for access, then connect thereto based upon the random AC value and a commercial carrier barring value received from said commercial carrier LTE base station.
    [2] 2. The LTE wireless communication system of Claim 1 wherein 25 said controller is configured to, when both said private LTE base station and said commercial carrier LTE base station are available for access, then connect to a base station based upon a preferred received network identification value.
    [3] 3. The LTE wireless communication system of Claim 1 wherein 30 said controller is configured to: -11- WO 2013/119426 PCT/US2013/023699 generate a comparative barring rate based upon one of the assigned AC value and the random AC value; and compare the comparative barring rate with one of the private LTE barring value and the commercial carrier barring value. 5
    [4] 4. The LTE wireless communication system of Claim 3 wherein said controller is configured to stop connecting to said private LTE base station when the comparative barring rate is greater than or equal to the respective private LTE barring value; and wherein said controller is configured to stop connecting to said 10 commercial carrier LTE base station when the comparative barring rate is greater than or equal to the commercial carrier barring value.
    [5] 5. The LTE wireless communication system of Claim 4 wherein said controller is configured to restart connecting to said private LTE base station or 15 said commercial carrier LTE base station after a barring time value has expired.
    [6] 6. The LTE wireless communication system of Claim 3 wherein said controller is configured to continue connecting to said private LTE base station or said commercial carrier LTE base station when the comparative barring rate is less 20 than the respective private LTE barring value or the commercial carrier barring value.
    [7] 7. The LTE wireless communication system of Claim 1 wherein said controller is configured to store the priority of use characteristic value comprising at least one of a first responder user value and a maintenance user value. 25
    [8] 8. A method of operating a long term evolution (LTE) mobile wireless communications device, the method comprising: storing an assigned access class (AC) value in a memory of the LTE mobile wireless communication device based upon a priority of use characteristic 30 value; -12- WO 2013/119426 PCT/US2013/023699 storing a random AC value in the memory; determining whether access is available to a private LTE base station or a commercial carrier LTE base station; when the private LTE base station is available for access, then 5 connecting thereto based upon the assigned AC value and a private LTE barring value received from the private LTE base station; and when the commercial carrier LTE base station is available for access, then connecting thereto based upon the random AC value and a commercial carrier barring value received from the commercial carrier LTE base station. 10
    [9] 9. The method of Claim 8 further comprising when both the private LTE base station and the commercial carrier LTE base station are available for access, then connect to a base station based upon a preferred received network identification value. 15
    [10] 10. The method of Claim 8 further comprising: generating a comparative barring rate based upon one of the assigned AC value and the random AC value; and comparing the comparative barring rate with one of the private LTE 20 barring value and the commercial carrier barring value. -13-
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    法律状态:
    2014-12-04| FGA| Letters patent sealed or granted (standard patent)|
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