Patent Publication Number: US-2023164575-A1

Title: Dynamic radio access technology bandwidth adaptation across asymmetric dss networks

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     None. 
     BACKGROUND 
     To overcome interference challenges observed with symmetric dynamic spectrum sharing (DSS) solution, operators are exploring asymmetric DSS solutions in which both Long Term Evolution (LTE) and New Radio (NR) can have different carrier bandwidths. Current implementation is to define shared bandwidth portion manually and does not have the flexibility to dynamically expand and reduce this shared bandwidth portion within the larger bandwidth depending on varying traffic profiles. 
     Consider a band-X with contiguous 30 megahertz (MHz) bandwidth with NR cell defined for the entire bandwidth while 10 MHz is being used as shared DSS cell for both LTE and NR users. If LTE traffic usage gradually increases and congests the entire 10 MHz bandwidth while the 30 MHz bandwidth is underutilized, there is no mechanism to dynamically expand the LTE bandwidth inside the 30 MHz band-X. Similarly, if LTE shared 10 MHz bandwidth is significantly underutilized while NR traffic is high, it would be ideal to reduce the LTE bandwidth to minimize interference and improve NR throughputs. 
     SUMMARY 
     A method and system are provided to dynamically expand and reduce certain DSS shared radio access technology (RAT) bandwidth based on traffic usages. LTE and NR can share contiguous spectrum in an intra band scenario. When the bandwidth of LTE or NR exceeds a threshold, the bandwidth can be incrementally increased by a pre-defined amount, especially when the corresponding bandwidth of the adjacent technology (ie. the adjacent NR or LTE in DSS) is being underutilized. Also, when the bandwidth of LTE or NR is underutilized, the bandwidth can be incrementally reduced by a pre-defined amount, especially when the corresponding bandwidth of the adjacent technology in DSS is exceeding its bandwidth threshold. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures, and wherein: 
         FIG.  1    is an illustration of dynamic spectrum sharing in band-X where New Radio (NR) bandwidth shares spectrum with Long Term Evolution (LTE) bandwidth, according to an implementation of an embodiment of the present invention; 
         FIG.  2    is an illustration of dynamic spectrum sharing in band-X where Long Term Evolution (LTE) bandwidth shares spectrum with New Radio (NR) bandwidth, according to an implementation of an embodiment of the present invention; 
         FIG.  3    illustrates a process for dynamically changing radio access technology (RAT) bandwidth based on traffic usage, according to an implementation of an embodiment of the present invention; and 
         FIG.  4    illustrates another process for dynamically changing radio access technology (RAT) bandwidth based on traffic usage, according to an implementation of an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The subject matter of embodiments of the invention is described with specificity herein to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. Rather, the inventors have contemplated that the claimed subject matter might be embodied in other ways, to include different steps or combinations of steps similar to the ones described in this document, in conjunction with other present or future technologies. Moreover, although the terms “step” and/or “block” may be used herein to connote different elements of methods employed, the terms should not be interpreted as implying any particular order among or between various steps herein disclosed unless and except when the order of individual steps is explicitly described. 
     Throughout this disclosure, several acronyms and shorthand notations are employed to aid the understanding of certain concepts pertaining to the associated system and services. These acronyms and shorthand notations are intended to help provide an easy methodology of communicating the ideas expressed herein and are not meant to limit the scope of embodiments described in the present disclosure. The following is a list of these acronyms: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 3G 
                 Third-Generation Wireless Technology 
               
               
                   
                 4G 
                 Fourth-Generation Cellular Communication System 
               
               
                   
                 5G 
                 Fifth-Generation Cellular Communication System 
               
               
                   
                 5GCN 
                 5G Core Network 
               
               
                   
                 BS 
                 Base Station 
               
               
                   
                 BTS 
                 Base Transceiver Station 
               
               
                   
                 CDMA 
                 Code Division Multiple Access 
               
               
                   
                 CDMA2000 
                 Code Division Multiple Access 2000 
               
               
                   
                 DSS 
                 Dynamic Spectrum Sharing 
               
               
                   
                 eNodeB or 
                 Evolved Node B 
               
               
                   
                 eNB 
                   
               
               
                   
                 gNB or 
                 Next Generation Node B 
               
               
                   
                 gNodeB 
                   
               
               
                   
                 GPRS 
                 General Packet Radio Service 
               
               
                   
                 GSM 
                 Global System for Mobile communications 
               
               
                   
                 IP 
                 Internet Protocol 
               
               
                   
                 LTE 
                 Long Term Evolution 
               
               
                   
                 MD 
                 Mobile Device 
               
               
                   
                 ME 
                 Mobile Equipment 
               
               
                   
                 ng-eNB 
                 Next Generation Evolved Node B 
               
               
                   
                 NR 
                 New Radio 
               
               
                   
                 OS 
                 Operating System 
               
               
                   
                 PC 
                 Personal Computer 
               
               
                   
                 PCS 
                 Personal Communications Service 
               
               
                   
                 RAT 
                 Radio Access Technology 
               
               
                   
                 RF 
                 Radio-Frequency 
               
               
                   
                 RFI 
                 Radio-Frequency Interference 
               
               
                   
                 SIM 
                 Subscriber Identity Module 
               
               
                   
                 TDMA 
                 Time Division Multiple Access 
               
               
                   
                 UE 
                 User Equipment 
               
               
                   
                 UMTS 
                 Universal Mobile Telecommunications Service 
               
               
                   
                 WCDMA 
                 Wideband Code Division Multiple Access 
               
               
                   
                 WiMAX 
                 Worldwide Interoperability for Microwave Access 
               
               
                   
                   
               
            
           
         
       
     
     Further, various technical terms are used throughout this description. 
     In a first aspect, a method and system of dynamically changing a radio access technology (RAT) bandwidth based on traffic usage is provided that includes operating dynamic spectrum sharing (DSS) in a mobile communications network that includes a first wireless standard technology and a second wireless standard technology. A radio network node is configured to operate and monitor traffic usage in a first RAT and a second RAT. The first RAT operates in the first wireless standard technology and the second RAT operates in the second wireless standard technology. The first RAT is configured to operate with a first bandwidth larger than the second RAT that is configured to operate with a second bandwidth. The first RAT and the second RAT are configured to operate with DSS for a particular band. The radio network node is configured to expand the second bandwidth of the second RAT by a pre-defined amount when a second RAT utilization is higher than a second operator-defined threshold and a first RAT utilization is lower than a first operator-defined threshold. The radio network node is configured to reduce the second bandwidth of the second RAT by the pre-defined amount when the second RAT utilization is lower than the second operator-defined threshold and the first RAT utilization is higher than the first operator-defined threshold. 
     In a second aspect, a method of dynamically changing a radio access technology (RAT) bandwidth based on traffic usage is provided that includes operating dynamic spectrum sharing (DSS) in a mobile communications network that includes 4G wireless technology and 5G wireless technology. A radio network node monitors traffic usage in Long Term Evolution (LTE) and New Radio (NR) and configures bandwidths for LTE and NR. LTE operates in 4G wireless technology and NR operates in 5G wireless technology. NR operates with a first bandwidth larger than LTE, which operates with a second bandwidth, where NR and LTE operate with DSS for a particular band. Or, NR operates with the first bandwidth smaller than LTE, which operates with the second bandwidth, where NR and LTE operate with DSS for the particular band. When NR has a larger assigned bandwidth than LTE, the second bandwidth of LTE is expanded by a pre-defined amount when a LTE utilization is higher than a LTE operator-defined threshold and a NR utilization is less than a NR operator-defined threshold. Also, when NR has a larger assigned bandwidth than LTE, the second bandwidth of LTE is reduced by the pre-defined amount when the LTE utilization is less than the LTE operator-defined threshold and the NR utilization is higher than the NR operator-defined threshold. When NR has a smaller assigned bandwidth than LTE, the first bandwidth of NR is expanded by a pre-defined amount when the NR utilization is higher than the NR operator-defined threshold and the LTE utilization is less than the LTE operator-defined threshold. Also, when NR has a smaller assigned bandwidth than LTE, the first bandwidth of NR is reduced by the pre-defined amount when the NR utilization is less than the NR operator-defined threshold and the LTE utilization is higher than the LTE operator-defined threshold. 
     In  FIG.  1   , a graph  100  illustrates LTE and NR functioning in a shared radio access technology bandwidth. Particularly, graph  100  is an illustration of the assignment of bandwidth for New Radio (NR)  110  in 5G wireless technology and Long Term Evolution (LTE)  120  in 4G wireless technology. The actual assignment of bandwidth occurs in either an eNodeB, gNB, or ng-eNB, which are the radio access technology devices used to connect cellular wireless devices back to a core network. As one can see in graph  100 , LTE shares bandwidth with NR, and this shared bandwidth is referred to as dynamic spectrum sharing (DSS). For example, NR  110  could have a bandwidth of 30 MHz and LTE  120  could have a bandwidth of 10 MHz. The DSS would be that portion of 10 MHz shared between NR and LTE. This sharing of bandwidth enables an operator to have both 4G LTE users and 5G NR users operate in a same band-X  105 . 
     In an implementation of an embodiment of the present invention, the bandwidth of NR  110  and LTE  120  can dynamically be adjusted to accommodate changes in traffic usage for 5G NR users and 4G LTE users. This can occur when there is a contiguous bandwidth spectrum in an intra band scenario. An operator configures bandwidth thresholds for NR  110  and LTE  120  in an eNodeB, gNB, or ng-eNB. For  FIG.  1   , when traffic usage for LTE  120  reaches the bandwidth threshold, the eNodeB, gNB, or ng-eNB checks the bandwidth for NR  110 . And if the traffic usage for NR  110  is less than its allocated bandwidth threshold, the eNodeB, gNB, or ng-eNB increases the bandwidth of LTE  120  by a pre-defined amount. The increase in bandwidth can occur up to a set maximum imposed by the operator Likewise, if the traffic usage for LTE  120  is less than the bandwidth threshold set for 4G LTE users and the traffic usage for NR  110  is more than the bandwidth threshold set for 5G NR users, the eNodeB, gNB, or ng-eNB reduces the bandwidth of LTE  120  by a pre-defined amount. The decrease in bandwidth can continue to occur down to a minimum set by the operator. 
     Turning now to  FIG.  2   , a graph  200  illustrates a converse of graph  100 . Graph  200  illustrates of NR and LTE functioning in a shared radio access technology bandwidth. Particularly, graph  200  is an illustration of the assignment of bandwidth for LTE  210  in 4G wireless technology and NR  220  in 5G wireless technology. As one can see in graph  200 , NR shares bandwidth with LTE, in DSS. For example, LTE  210  could have a bandwidth of 30 MHz and NR  220  could have a bandwidth of 10 MHz. The DSS would be that portion of 10 MHz shared between NR and LTE. This sharing of bandwidth enables the operator to have both 4G LTE users and 5G NR users operate in a same band-X  205 , similar to band-X  105 . 
     As stated before for NR  110  and LTE  120 , LTE  210  and NR  220  can dynamically be adjusted to accommodate changes in traffic usage for 4G LTE users and 5G NR users. The operator configures bandwidth thresholds for LTE  210  and NR  220 , which might be slightly less than the full bandwidths shown in graph  200  in  FIG.  2   . For example, if LTE has a bandwidth of 30 MHz and NR  220  has a bandwidth of 10 MHz, the operator may allocate bandwidth thresholds that are less than the bandwidth maximums in order to reduce interference. Therefore, when traffic user for NR  220  reaches the bandwidth threshold, the eNodeB, gNB, or ng-eNB can check the bandwidth of LTE  210 . If the traffic usage for LTE  210  is less than the allocated bandwidth threshold, the eNodeB, gNB, or ng-eNB can incrementally increase the bandwidth of NR  220  by a pre-defined amount. Likewise, if the traffic usage for NR  220  is less than the bandwidth threshold set for 5G NR users and the traffic usage for LTE  210  is more than the bandwidth threshold set for 4G LTE users, the eNodeB, gNB, or ng-eNB (or any other assigned radio access technology) can reduce the bandwidth of NR  220  by a pre-defined amount. The decrease can continue in a loop or repetitive arrangement until a minimum set by the operator is reached. 
     Turning now to  FIG.  3   , a method for dynamically changing radio access technology (RAT) bandwidth based on traffic usage is provided in a process  300 . In a step  310 , dynamic spectrum sharing (DSS) is provided in a mobile communications network that includes a first wireless standard technology and a second wireless standard technology. In a step  320 , a radio network node monitors traffic usage in a first radio access technology (RAT) (e.g. NR  110 , LTE  210 ) and a second radio access technology (RAT) (e.g. LTE  120 , NR  220 ). The first RAT operates in the first wireless standard technology and the second RAT operates in the second wireless standard technology, in a step  330 . In a step  340 , the first RAT has a first bandwidth larger than the second RAT with a second bandwidth, with DSS for a particular band. In a step  350 , the second bandwidth of the second RAT is expanded by a pre-defined amount when a second RAT utilization is higher than a second operator-defined threshold, and a first RAT utilization is less than a first operator-defined threshold. The second bandwidth of the second RAT is reduced by the pre-defined amount when the second RAT utilization is less than the second operator-defined threshold, and the first RAT utilization is higher than the first operator-defined threshold, in a step  360 . 
     Turning now to  FIG.  4   , a method for dynamically changing radio access technology (RAT) bandwidth based on traffic usage is provided in a process  400 . In a step  410 , dynamic spectrum sharing (DSS) is provided in a mobile communications network that includes a 4G wireless technology and a 5G wireless technology. A radio network node monitors traffic usage in Long Term Evolution (LTE) (e.g. LTE  120 , LTE  210 ) and New Radio (NR) (e.g. NR  110 , NR  220 ) and configures bandwidths for LTE and NR, in a step  420 . LTE operates in 4G wireless technology and NR operates in 5G wireless technology, in a step  430 . In a step  440 , NR has a first bandwidth that is larger than LTE with a second bandwidth for a particular band. Or, NR has the first bandwidth that is smaller than LTE with the second bandwidth for the particular band. When NR has a larger assigned bandwidth than LTE, the second bandwidth of LTE is expanded by a pre-defined amount when a LTE utilization is higher than a LTE operator-defined threshold and a NR utilization is less than a NR operator-defined threshold, in a step  450 . In a step  460 , When NR has the larger assigned bandwidth than LTE, the second bandwidth of LTE is reduced by the pre-defined threshold amount when the LTE utilization is less than the LTE operator-defined threshold and the NR utilization is higher than the NR operator-defined threshold. In a step  470 , when NR has a smaller assigned bandwidth than LTE, the first bandwidth of NR is expanded by a pre-defined amount when the NR utilization is higher than the NR operator-defined threshold and the LTE utilization is less than the LTE operator-defined threshold. In a step  480 , when NR has a smaller assigned bandwidth than LTE, the first bandwidth of NR is reduced by the pre-defined amount when the NR utilization is less than the NR operator-defined threshold and the LTE utilization is higher than the LTE operator-defined threshold.