Patent Publication Number: US-9894677-B1

Title: Systems and methods for configuring a scheduler at an access node

Description:
TECHNICAL BACKGROUND 
     Telecommunication systems, such as cellular networks or other wireless networks, use various network links throughout the network to communicate. For example, an access node may use a network link to communicate with another access node while using a separate network link to communicate with another processing node. Accordingly, the system may rely on a well-established network to provide efficient communication services. 
     In certain circumstances, a portion of the network may experience high load (e.g., load above a threshold) or poor channel conditions. For example, a communication link may experience large amount of data traffic or poor channel conditions may render a communication link less effective, and the efficiency of the system may suffer. Accordingly, a system that effectively balances load and considers channel conditions may be able to provide a high quality service to users of the system. 
     OVERVIEW 
     Systems and methods are described for configuring a scheduler at an access node. At least two regions may be determined for a coverage area of an access node, wherein a first region is bounded by a first distance from the access node and a second region is bounded by a second distance from the access node such that the second distance is greater than the first distance. Wireless transmissions may be scheduled from the access node based on a fairness algorithm such that the fairness algorithm schedules wireless transmissions to wireless devices associated with the first region based on throughput for the wireless devices associated with the first region and the fairness algorithm schedules wireless transmissions to wireless devices associated with the second region based on throughput for wireless devices associated with the second region. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exemplary communication system to configure a scheduler at an access node. 
         FIG. 2  illustrates another exemplary communication system to configure a scheduler at an access node. 
         FIG. 3  illustrates an exemplary method for configuring a scheduler at an access node. 
         FIG. 4  illustrates another exemplary communication system to configure a scheduler at an access node. 
         FIG. 5  illustrates another exemplary communication system to configure a scheduler at an access node. 
         FIG. 6  illustrates another exemplary method for configuring a scheduler at an access node. 
         FIG. 7  illustrates an exemplary processing node. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates an exemplary communication system  100  to configure a scheduler at an access node comprising wireless device  102 , access node  104 , communication network  106 , and communication links  108  and  110 . Other network elements may be present in the communication system  100  to facilitate communication but are omitted for clarity, such as controller nodes, base stations, base station controllers, gateways, mobile switching centers, dispatch application processors, and location registers such as a home location register or visitor location register. Furthermore, other network elements may be present to facilitate communication between access node  104  and communication network  106  which are omitted for clarity, including additional processing nodes, routers, gateways, and physical and/or wireless data links for carrying data among the various network elements. 
     Wireless device  102  can be any device configured to communicate over communication system  100  using a wireless communication link. For example, wireless device  102  can include a cell phone, a smart phone, a computing platform such as a laptop, palmtop, or a tablet, a personal digital assistant, or an internet access device, and combinations thereof. It is noted that while one wireless device is illustrated in  FIG. 1  as being in communication with access node  104 , any number of wireless devices can be implemented. 
     Access node  104  is a network node capable of providing wireless communications to wireless device  102 , and can be, for example, a base transceiver station, a radio base station, and an eNodeB device. Access node  104  may communicate with communication network  106  over communication link  110 . Although only access node  104  is illustrated in  FIG. 1 , wireless device  102  (and other wireless devices not depicted) can be in communication with a plurality of access nodes and/or small cells. The plurality of access nodes and/or small cells can be associated with different networks and can support different communication protocols and radio access technologies. 
     Communication network  106  can be a wired and/or wireless communication network, and can comprise processing nodes, routers, gateways, and physical and/or wireless data links for carrying data among various network elements, including combinations thereof, and can include a local area network, a wide area network, and an internetwork (including the Internet). Communication network  106  can be capable of carrying voice information and other information, for example, to support communications by a wireless device such as wireless device  102 . Wireless network protocols may comprise code division multiple access (CDMA) 1×RTT, Global System for Mobile communications (GSM), Universal Mobile Telecommunications System (UMTS), High-Speed Packet Access (HSPA), Evolution Data Optimized (EV-DO), EV-DO rev. A, and Third Generation Partnership Project Long Term Evolution (3GPP LTE). Wired network protocols that may be utilized by communication network  106  comprise Ethernet, Fast Ethernet, Gigabit Ethernet, Local Talk (such as Carrier Sense Multiple Access with Collision Avoidance), Token Ring, Fiber Distributed Data Interface (FDDI), and Asynchronous Transfer Mode (ATM). Communication network  106  may also comprise a wireless network, including base stations, wireless communication nodes, telephony switches, internet routers, network gateways, computer systems, communication links, or some other type of communication equipment, and combinations thereof. 
     Communication links  108  and  110  can be wired or wireless communication links. Wired communication links can comprise, for example, twisted pair cable, coaxial cable or fiber optic cable, or combinations thereof. Wireless communication links can comprise a radio frequency, microwave, infrared, or other similar signal, and can use a suitable communication protocol, for example, GSM, CDMA, UMTS, HSPA, EV-DO, or 3GPP LTE, or combinations thereof. Other wireless protocols can also be used. 
       FIG. 2  illustrates an exemplary communication system  200  for configuring a scheduler at an access node. System  200  comprises wireless devices  202 ,  204 ,  206 , and  208 , access node  210 , and coverage regions  212  and  214 . Wireless devices  202 ,  204 ,  206 , and  208  may comprise wireless devices similar to wireless device  102  and access node  210  may comprise an access node similar to access node  104 . 
     In an embodiment, system  200  may use a plurality of carriers in order to provide wireless communication services. A plurality of carriers that comprise bandwidth for wireless communications (e.g., 2.5 GHz carrier, 1900 Mhz carrier, and 800 Mhz carrier, and the like) may include a plurality of channels (e.g., 5 Mhz channels, 10 Mhz channels, 15 Mhz channels, and the like) that may further be divided into subcarriers. 
     In an embodiment, a signal area may comprise an area around an access node where a wireless device may detect wireless signals transmitted from the access node (e.g., a references signal) at a signal level above a threshold. In this example, access node  210  may comprise a signal area that is partitioned into coverage regions  212  and  214 . For example, coverage region  212  may comprise the region between access node  210  and a first distance, illustrated by the inner concentric circle, and coverage region  214  may comprise the region between region  212  and a second distance, illustrated by the outer concentric circle. Access node  210  may transmit wireless signals over one or more particular band classes (BCs). A band class may comprise a block of wireless spectrum. In an embodiment, a frequency band may comprise a band class. Examples of such band classes may be blocks of spectrum at 800 MHz, 1,900 MHz, and 2,500 MHz 
     In operation, access node  210  may establish communication with wireless devices  202 ,  204 ,  206 , and  208  such that access node  210  provides the wireless devices access to a communication network (e.g., communication network  106 ). Access node  210  may schedule transmissions (e.g., physical resource block transmissions) to wireless devices in communication with the access node. For example, a packet may be received at access node  210  that is associated with wireless device  202 , and access node  210  may schedule one or more transmissions to wireless device  202  to communicate the data from the received packet. 
     In an embodiment, access node  210  may schedule transmissions according to a fairness algorithm. For example, for each wireless device in communication with an access node, a scheduler may calculate k such that k=arg max r i (t)/R i (t). Here, R i (t) may comprise an average data rate for wireless device i over a time window, and r i (t) may comprise an instantaneous data rate (e.g., average instantaneous data rate) for wireless device i. A fairness algorithm may then schedule a transmission for the wireless device that comprises the greatest k value. 
     In some embodiments, fairness algorithms may limit throughput for an access node. For example, wireless devices  202  and  204  may be closer in proximity to the access node  210 , and therefore may comprise a greater channel quality (e.g., CQI) than wireless devices  208  and  206 . As such, when communicating with access node  210 , wireless devices  202  and  204  may be able to achieve a higher throughput (e.g., use a more efficient modulation and coding scheme) than wireless devices  206  and  208 . Accordingly, when scheduling wireless resources (e.g., physical resource block transmissions), fairness to wireless devices  206  and  208  may limit throughput. A system that balances fairness and throughput may be able to provide efficient wireless communications. 
     Systems and methods are described for configuring a scheduler at an access node. At least two regions may be determined for a coverage area of an access node, wherein a first region is bounded by a first distance from the access node and a second region is bounded by a second distance from the access node such that the second distance is greater than the first distance. Wireless transmissions may be scheduled from the access node based on a fairness algorithm such that the fairness algorithm schedules wireless transmissions to wireless devices associated with the first region based on throughput for the wireless devices associated with the first region and the fairness algorithm schedules wireless transmissions to wireless devices associated with the second region based on throughput for wireless devices associated with the second region. 
       FIG. 3  illustrates an exemplary method for configuring a scheduler at an access node. The method will be discussed with reference to the exemplary communication system  200  illustrated in  FIG. 2 , however, the method can be implemented with any suitable communication system. 
     Referring to  FIG. 3 , at step  302 , at least two regions may be determined for a coverage area of an access node, wherein a first region is bounded by a first distance from the access node and a second region is bounded by a second distance from the access node such that the second distance is greater than the first distance. For example, coverage regions  212  and  214  may be determined for the coverage area of access node  210 . Coverage region  212  may comprise the region between access node  210  and a first distance, illustrated by the inner concentric circle, and coverage region  214  may comprise the region between region  212  and a second distance, illustrated by the outer concentric circle. 
     At step  304 , wireless transmissions may be scheduled from the access node based on a fairness algorithm such that the fairness algorithm schedules wireless transmissions to wireless devices associated with the first region based on throughput fairness for the wireless devices associated with the first region and the fairness algorithm schedules wireless transmissions to wireless devices associated with the second region based on throughput fairness for wireless devices associated with the second region. For example, wireless transmissions may be scheduled from access node  210  to wireless devices  202 ,  204 ,  206 , and  208 . The wireless transmission may be scheduled based on a coverage region associated with the wireless devices. For example, wireless devices  202  and  204  may be associated with coverage region  212  and wireless devices  206  and  208  may be associated with coverage region  214 . 
     In an embodiment, a scheduling metric may be calculated for each of wireless devices  202 ,  204 ,  206  and  208 . The scheduling metric for each wireless device may be calculated based on the throughput for the particular wireless device. Access node  210  may schedule transmissions for region  212  based on the calculated scheduling metrics for wireless devices  202  and  204 , and may schedule transmissions for region  214  based on the calculated scheduling metrics for wireless devices  206  and  208 . In an embodiment, access node  210  may schedule a transmission for region  212  to the wireless device associated with that region that comprises the greatest calculated metric (e.g., one of wireless devices  202  and  204 ), and may schedule a transmission for region  214  to the wireless device associated with that region that comprises the greatest calculated metric (e.g., one of wireless devices  206  and  208 ). 
     In an embodiment, access node  202  may schedule transmissions for any of regions  212  and  214  based on the calculated scheduling metrics for wireless devices  202 ,  204 ,  206  and  208 . In an embodiment, the calculated scheduling metric for a wireless device may be based on a determined fairness for the region associated with that wireless device, as described herein. Here, the wireless device with the highest calculated scheduling metric may be scheduled the next available transmission (e.g., physical resource block) for any of regions  212  and  214 . Wireless transmissions may comprise the transmission of one or more physical resources blocks (PRBs). 
       FIG. 4  illustrates another exemplary communication system  400  to configure a scheduler at an access node. Communication system  400  may comprise wireless devices  402  and  404 , access node  406  and  408 , controller node  410 , gateway node  412 , communication network  414 , and communication links  416 ,  418 ,  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 , and  434 . Other network elements may be present in the communication system  400  to facilitate communication but are omitted for clarity, such as base stations, base station controllers, gateways, mobile switching centers, dispatch application processors, and location registers such as a home location register or visitor location register. 
     Wireless device  402  and  404  can be any devices configured to communicate over communication system  400  using a wireless communication link. For example, wireless devices  402  and  404  can include a cell phone, a smart phone, a computing platform such as a laptop, palmtop, or a tablet, a personal digital assistant, or an internet access device, and combinations thereof. 
     Access nodes  406  and  408  are network nodes capable of providing wireless communications to wireless devices  402  and  404 , and can be, for example, a base transceiver station, a radio base station, or an eNodeB device. In an embodiment, access node  406  can comprise a serving access node for wireless devices  402  and  404 . Access nodes  406  and  408  may communicate with controller node  410  over communication links  424  and  426 , respectively, and with gateway node  412  over communication links  428  and  430 , respectively. Access nodes  406  and  408  may also communicate directly with each other over communication link  422 . 
     Controller node  410  can be any network node configured to manage services within system  400 . Controller node  410  may provide other control and management functions for system  400 . The controller node  410  can be a single device having various functions or a plurality of devices having differing functions. For example, controller node  410  can include at least one of a multi-cell/multicast coordination entity (MCE), a mobility management entity (MME), a mobile switching center (MSC), a radio network controller (RNC), and a combination thereof. 
     Controller node  410  can comprise a processor and associated circuitry to execute or direct the execution of computer-readable instructions to obtain information. Controller node  410  can retrieve and execute software from storage, which can include a disk drive, a flash drive, memory circuitry, or some other memory device, and which can be local or remotely accessible. The software may comprise computer programs, firmware, or some other form of machine-readable instructions, and may include an operating system, utilities, drivers, network interfaces, applications, or some other type of software, including combinations thereof. Controller node  410  can receive instructions and other input at a user interface. Controller node  410  can comprise a processor and associated circuitry to execute or direct the execution of computer-readable instructions to obtain information. 
     Gateway node  412  is a network element which can comprise a processor and associated circuitry to execute or direct the execution of computer-readable instructions. Gateway node  412  may retrieve and execute software from storage, which can include a disk drive, flash drive, memory circuitry, or some other memory device, and which can be local or remotely accessible. The software comprises computer programs, firmware, or some other form of machine-readable instructions, and may include an operating system, utilities, drivers, network interfaces, applications, or some other type of software, including combinations thereof. In an embodiment, gateway node  412  can provide instructions to access nodes  406  and  408  related to channel selection in communications with wireless devices  402  and  404 . For example, gateway node  412  can comprise at least one of a serving gateway (SGW), a packet data network gateway (PDNGW), a cellular gateway (CGW), and a combination thereof. 
     Communication network  414  can be a wired and/or wireless communication network, and can comprise processing nodes, routers, gateways, and physical and/or wireless data links for carrying data among various network elements, including combinations thereof, and can include a local area network, a wide area network, and an internetwork (including the Internet). Communication network  414  may also comprise base stations, wireless communication nodes, telephony switches, internet routers, network gateways, computer systems, communication links, or some other type of communication equipment, and combinations thereof. Wireless network protocols may comprise code division multiple access (CDMA) 1×RTT, Global System for Mobile communications (GSM), Universal Mobile Telecommunications System (UMTS), High-Speed Packet Access (HSPA), Evolution Data Optimized (EV-DO), EV-DO rev. A, and Third Generation Partnership Project Long Term Evolution (3GPP LTE). Wired network protocols that may be utilized by communication network  414  comprise Ethernet, Fast Ethernet, Gigabit Ethernet, Local Talk (such as Carrier Sense Multiple Access with Collision Avoidance), Token Ring, Fiber Distributed Data Interface (FDDI), and Asynchronous Transfer Mode (ATM). 
     Communication links  416 ,  418 ,  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 , and  434  can be wired or wireless communication links. Wired communication links can be, for example, twisted pair cable, coaxial cable or fiber optic cable, or combinations thereof. Wireless communication links can be a radio frequency, microwave, infrared, or other similar signal, and can use a suitable communication protocol, for example, Global System for Mobile telecommunications (GSM), Code Division Multiple Access (CDMA), or Long Term Evolution (LTE), or combinations thereof. Other wireless protocols can also be used. 
     Other network elements may be present in the communication system  400  to facilitate wireless communication but are omitted for clarity, such as base stations, base station controllers, gateways, mobile switching centers, dispatch application processors, and location registers such as a home location register or visitor location register. Furthermore, other network elements may be present to facilitate communication among access nodes  406  and  408 , controller node  410 , gateway node  412 , and communication network  414  which are omitted for clarity, including additional processing nodes, routers, gateways, and physical and/or wireless data links for carrying data among the various network elements. In an embodiment, any of controller node  410 , gateway node  412 , and one or more modules of access nodes  406  and/or  408  may perform all or parts of the methods of  FIGS. 3 and 6 . 
       FIG. 5  illustrates an exemplary communication system  500  for configuring a scheduler at an access node. System  500  comprises wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512 , access node  514 , and coverage regions  516 ,  518 , and  520 . Wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512  may comprise wireless devices similar to wireless device  402  and access node  514  may comprise an access node similar to access node  406 . 
     In an embodiment, system  500  may use a plurality of carriers in order to provide wireless communication services. A plurality of carriers that comprise bandwidth for wireless communications (e.g., 2.5 GHz carrier, 1900 Mhz carrier, and 800 Mhz carrier, and the like) may include a plurality of channels (e.g., 5 Mhz channels, 10 Mhz channels, 15 Mhz channels, and the like) that may further be divided into subcarriers. 
     In an embodiment, a signal area may comprise an area around an access node where a wireless device may detect wireless signals transmitted from the access node (e.g., a references signal) at a signal level above a threshold. In this example, access node  514  may comprise a signal area that is partitioned into coverage regions  516 ,  518  and  520 . For example, coverage region  516  may comprise the region between access node  514  and a first distance, illustrated by the inner concentric circle, coverage region  518  may comprise the region between region  516  and a second distance, illustrated by the middle concentric circle, and coverage region  520  may comprise the region between region  518  and a third distance, illustrated by the outer concentric circle. Access node  514  may transmit wireless signals over one or more particular band classes (BCs). A band class may comprise a block of wireless spectrum. In an embodiment, a frequency band may comprise a band class. Examples of such band classes may be blocks of spectrum at 800 MHz, 1,900 MHz, and 2,500 MHz 
     In operation, access node  514  may establish communication with wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512  such that access node  514  provides the wireless devices access to a communication network (e.g., communication network  414 ). Access node  514  may schedule transmissions (e.g., physical resource block transmissions) to wireless devices in communication with the access node. For example, a packet may be received at access node  514  that is associated with wireless device  502 , and access node  514  may schedule one or more transmissions to wireless device  502  to communicate the data from the received packet. 
     In an embodiment, access node  514  may schedule transmissions according to a fairness algorithm. For example, for each wireless device in communication with an access node, a scheduler may calculate k such that k=arg max r i (t)/R i (t). Here, R i (t) may comprise an average data rate for wireless device i over a time window, and r i (t) may comprise an instantaneous data rate (e.g., average instantaneous data rate) for wireless device i. A fairness algorithm may then schedule a transmission for the wireless device that comprises the greatest k value. 
     In some embodiments, fairness algorithms may limit throughput for an access node. For example, wireless devices  502  and  504  may be closer in proximity to the access node  514 , and therefore may comprise a greater channel quality (e.g., CQI) than wireless devices  510  and  512 . As such, when communicating with access node  514 , wireless devices  502  and  504  may be able to achieve a higher throughput (e.g., use a more efficient modulation and coding scheme) than wireless devices  510  and  512 . Accordingly, when scheduling wireless resources (e.g., physical resource block transmissions), fairness to wireless devices  510  and  512  may limit throughput. A system that balances fairness and throughput may be able to provide efficient wireless communications. 
     Systems and methods are described for configuring a scheduler at an access node. At least two regions may be determined for a coverage area of an access node, wherein a first region is bounded by a first distance from the access node and a second region is bounded by a second distance from the access node such that the second distance is greater than the first distance. Wireless transmissions may be scheduled from the access node based on a fairness algorithm such that the fairness algorithm schedules wireless transmissions to wireless devices associated with the first region based on throughput fairness for the wireless devices associated with the first region and the fairness algorithm schedules wireless transmissions to wireless devices associated with the second region based on throughput fairness for wireless devices associated with the second region. 
       FIG. 6  illustrates an exemplary method for configuring a scheduler at an access node. The method will be discussed with reference to the exemplary communication system  500  illustrated in  FIG. 5 , however, the method can be implemented with any suitable communication system. 
     Referring to  FIG. 6  at step  602 , at least two regions may be determined for a coverage area of an access node, wherein a first region is bounded by a first distance from the access node and a second region is bounded by a second distance from the access node such that the second distance is greater than the first distance. For example, coverage regions  516 ,  518 , and  520  may be determined for the coverage area of access node  514 . Coverage region  516  may comprise the region between access node  514  and a first distance, illustrated by the inner concentric circle, coverage region  518  may comprise the region between region  516  and a second distance, illustrated by the middle concentric circle, and coverage region  520  may comprise the region between region  518  and a third distance, illustrated by the outer concentric circle. 
     In an embodiment, the first distance, second distance, and third distance may be based on a percentage of area covered by each coverage region for the coverage area of access node  514 . For example, the first distance may be determined such that coverage region  516  covers 50% of the coverage area, the second distance may be determined such that coverage region  518  covers 25% of the coverage area, and the third distance may be determined such that coverage area  520  covers 25% of the coverage area. In this example, coverage area  516  comprises the coverage area that provides wireless devices with the highest channel quality connections with access node  514  (e.g., coverage area associated with highest throughput for wireless devices), coverage area  518  comprises the coverage area that provides wireless devices with the second highest channel quality connections with access node  514  (e.g., coverage area associated with second highest throughput for wireless devices), and coverage area  520  comprises the coverage area that provides wireless devices with the lowest channel quality connections with access node  514  (e.g., coverage area associated with lowest throughput for wireless devices). 
     In an embodiment, the first distance, second distance, and third distance may be based on a coverage area for band classes used to provide wireless services at access node  514 . For example, the first distance may be determined based on a coverage area for a first band class, the second distance may be determined based on a coverage area for a second band class, and the third distance may be determined based on a coverage area for a third band class. In this example, coverage area  516  may provide wireless devices with the highest throughput connections because the first band class may be associated with the highest throughput connections, coverage area  518  may provide wireless devices with the second highest throughput connections because the second band class may be associated with the second highest throughput connections, and coverage area  520  may provide wireless devices with the lowest throughput connections because the third band class may be associated with the lowest throughput connections. 
     At step  604 , resources may be allocated to the coverage regions, wherein a first set of wireless resources at the access node are allocated to the first region, a second set of wireless resources at the access node are allocated to the second region, and a third set of wireless resources are allocated to the third region. For example, wireless resources at access node  514  may be allocated to regions  516 ,  518  and  520 . 
     In an embodiment, the allocation may be based on a percentage of wireless devices associated with each region. For example, 50% of users may be associated with region  516 , 35% with region  518 , and 15% with region  520 . Accordingly, region  516  may be allocated 50% of the wireless resources (e.g., available physical resource block transmissions) at access node  514 , region  518  may be allocated 35% of the wireless resources at access node  514 , and region  520  may be allocated 15% of the wireless resources at access node  514 . 
     In another embodiment, the allocation may be based on a historical percentage of wireless devices associated with each region. For example, over a period of time (e.g., hours, days, months, and the like), a historical average may indicate that 50% of users are associated with region  516 , 35% with region  518 , and 15% with region  520 . Accordingly, the allocations to regions  516 ,  518 , and  520 , as described herein, may be performed. In an embodiment, the allocation may be based on a historical percentage of wireless devices associated with each region at a particular time. For example, a historical average may indicate that at 9:00 am on a Monday, 50% of users are associated with region  516 , 35% with region  518 , and 15% with region  520 , however at 4:00 pm on a Saturday, 70% of users are associated with region  516 , 15% with region  518 , and 15% with region  520 . Accordingly, the allocations to regions  516 ,  518 , and  520 , as described herein, may be performed. In an embodiment, wireless resources at access node  514  may be allocated to the coverage regions in any other suitable manner. 
     In an embodiment, the same wireless resources may be allocated to all of regions  516 ,  518 , and  520 . For example, a set of physical resources blocks may be available for scheduling, and the physical resources blocks may be scheduled to any of regions  516 ,  518 , and  520  (e.g., based on the scheduling metrics calculated for wireless devices associated with the region, as described herein). 
     At step  606 , a scheduling metric may be calculated for each wireless device associated with each region. For example, a fairness metric may be calculated for each wireless devices associated with each of regions  516 ,  518 , and  520 . 
     In an embodiment, a wireless device may be associated with a region based on a channel quality indicator (CQI) for the wireless device. For example, region  516  may be associated with a first set of CQIs, region  518  may be associated with a second set of CQIs, and region  520  may be associated with a third set of CQIs. Accordingly, a wireless device may be associated with a region based on the CQI reported for the wireless device. 
     In an embodiment, a wireless device may be associated with a region based on a modulation and coding scheme for the wireless device. For example, region  516  may be associated with a first set of modulation and coding schemes, region  518  may be associated with a second set of modulation and coding schemes, and region  520  may be associated with a third set of modulation and coding schemes. Accordingly, a wireless device may be associated with a region based on the modulation and coding scheme the wireless device uses to communicate with access node  514 . 
     In an embodiment, a wireless device may be associated with a region based on a location for the wireless device. For example, region  516  may be associated with a first geographic region (e.g., from the location of access node  414  to the first distance), region  518  may be associated with a second geographic region (e.g., from the first distance to the second distance), and region  520  may be associated with a third geographic region (e.g., from the second distance to the third distance). Accordingly, a wireless device may be associated with a region based on which geographic region in which the wireless device is located. 
     In an embodiment, a scheduling metric may be calculated for wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512 . For example, the scheduling metric may be based on an average data rate and an instantaneous data rate for the wireless device. In an embodiment, the scheduling metric may comprise: k i =arg max r i (t)/R i (t). Here, R i (t) may comprise an average data rate (or throughput) for wireless device i over a time window, and r i (t) may comprise an instantaneous data rate or throughput (e.g., average instantaneous data rate or throughput) for wireless device i. 
     In another embodiment, the scheduling metric may be based on a channel quality indicator (CQI), average data rate (or throughput), and fairness calculated for the wireless device. For example, the scheduling metric may comprise: 
     
       
         
           
             
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     Here, CQI i  may comprise the channel quality indicator for wireless device i, R i  may comprise an average data rate (or throughput) for wireless device i over a time window, and Fairness, may comprise a calculated fairness for wireless device i, where the calculated fairness comprises the fairness for the wireless device based on (e.g., relative to) the coverage region associated with the wireless device. The fairness metric may comprise a value between 0 and 1 that indicates the fairness for the coverage region associated with the wireless device. 
     In an embodiment, the fairness metric may comprise: 
     
       
         
           
             Fairness 
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     Here, x i  may comprise a data rate (or throughput) for wireless device i, where the Fairness is calculated based on summations over wireless devices i to n, as represented above. In this example, a fairness metric may be calculated for a coverage region based on the wireless devices associated with the particular coverage region. In an embodiment, coverage region  516  may comprise a first wireless device, a second wireless device, and a third wireless device. Here, the fairness metric may be calculated for region  516 , where n=3, and where the data rate (or throughput) for each of the three wireless devices is used to determine the metric, as illustrated above. 
     In an embodiment, k i  (scheduling metric) may be calculated for wireless device  502  based on a CQI for wireless device  502  (CQI i ), an average throughput for wireless device  502  (R i ), and a calculated fairness metric for the coverage region associated with wireless device  502  (Fairness i ), that is coverage region  516 . In this example, the calculated fairness metric for coverage region  516  may be determined based on the data rates (or throughputs) for the wireless devices associated with region  516  (x i ). A k i  may similarly be calculated for each of wireless devices  504 ,  506 ,  508 ,  510 , and  512  based on Fairness metrics for regions  516 ,  518 , and  520 . 
     At step  608 , wireless transmissions may be scheduled from the access node based on a fairness algorithm such that the fairness algorithm schedules wireless transmissions to wireless devices associated with the first region based on throughput fairness for the wireless devices associated with the first region, the fairness algorithm schedules wireless transmissions to wireless devices associated with the second region based on throughput fairness for wireless devices associated with the second region, and the fairness algorithm schedules wireless transmissions to wireless devices associated with the third region based on throughput fairness for wireless devices associated with the third region. For example, wireless transmissions may be scheduled from access node  514  to wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512 . The wireless transmission may be scheduled based on a coverage region associated with the wireless devices. In an embodiment, wireless devices  502  and  504  may be associated with region  516 , wireless devices  506  and  508  may be associated with region  518 , and wireless devices  510  and  512  may be associated with region  520 . 
     In an embodiment, a scheduling metric may be calculated for each of wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512 , as described herein. Access node  514  may schedule transmissions for region  516  based on the calculated scheduling metrics for wireless devices  502  and  504 , may schedule transmissions for region  518  based on the calculated scheduling metrics for wireless devices  506  and  508 , and may schedule transmissions for region  520  based on the calculated scheduling metrics for wireless devices  510  and  512 . For example, wireless resources may be allocated to each or regions  516 ,  518 , and  520 , and transmissions may be scheduled based on the allocations. In an embodiment, access node  514  may schedule a transmission for region  516  to the wireless device associated with that region that comprises the greatest calculated scheduling metric (e.g., one of wireless devices  502  and  504 ), may schedule a transmission for region  518  to the wireless device associated with that region that comprises the greatest calculated scheduling metric (e.g., one of wireless devices  506  and  508 ), and may schedule a transmission for region  520  to the wireless device associated with that region that comprises the greatest calculated scheduling metric (e.g., one of wireless devices  510  and  512 ). 
     In an embodiment, wireless transmission may be scheduled for a coverage region based on the allocated wireless resources for that region. For example, access node  514  may schedule a transmission for region  516  from a first set of wireless resources associated with the region, may schedule a transmission for region  518  from a second set of wireless resources associated with the region, and may schedule a transmission for region  520  from a third set of wireless resources associated with the region. 
     In an embodiment, access node  514  may schedule transmissions for any of regions  516 ,  518 , and  520  based on the calculated scheduling metrics for wireless devices  502 ,  504 ,  506 ,  508 ,  510 , and  512 . For example, access node  514  may use a set of resources for all of regions  516 ,  518 , and  520 . In an embodiment, the calculated scheduling metric for a wireless device may be based on a determined fairness for the region associated with that wireless device, as described herein. Here, the wireless device with the highest calculated scheduling metric may be scheduled the next available transmission (e.g., physical resource block) for any of regions  516 ,  518 , and  520 . 
     In an embodiment, regions  516 ,  518 , and  520  may be associated with a first band class, a second band class, and a third band class respectively. In this example, a fairness metric (as described herein) may be calculated relative to each band class, and a scheduling metric for each wireless device (as described herein) may be calculated relative to the band class associated with the wireless device. In an embodiment, where a calculated fairness metric for a particular band class falls below a criteria (e.g., threshold fairness), one or more wireless devices communicating over that particular band class may be instructed to switch to another band class. Subsequently, a new fairness metric may be calculated for each of the band classes after handover. Transmissions may then be scheduled from the access node to wireless devices according to the new fairness metrics (and subsequently calculated scheduling metrics for the wireless devices). 
     Although the methods described perform steps in a particular order for purposes of illustration, the methods discussed herein are not limited to any particular order or arrangement. One skilled in the art, using the disclosure provided herein, will appreciate that various steps of the methods can be omitted, rearranged, combined, and/or adapted in various ways. 
       FIG. 7  illustrates an exemplary processing node  700  in a communication system. Processing node  700  comprises communication interface  702 , user interface  704 , and processing system  706  in communication with communication interface  702  and user interface  704 . Processing node  700  can be configured to determine a communication access node for a wireless device. Processing system  706  includes storage  708 , which can comprise a disk drive, flash drive, memory circuitry, or other memory device. Storage  708  can store software  710  which is used in the operation of the processing node  700 . Storage  708  may include a disk drive, flash drive, data storage circuitry, or some other memory apparatus. Software  710  may include computer programs, firmware, or some other form of machine-readable instructions, including an operating system, utilities, drivers, network interfaces, applications, or some other type of software. Processing system  706  may include a microprocessor and other circuitry to retrieve and execute software  710  from storage  708 . Processing node  700  may further include other components such as a power management unit, a control interface unit, etc., which are omitted for clarity. Communication interface  702  permits processing node  700  to communicate with other network elements. User interface  704  permits the configuration and control of the operation of processing node  700 . 
     Examples of processing node  700  include controller node  410  and gateway node  412 . Processing node  700  can also be an adjunct or component of a network element, such as an element of access nodes  104  or  406  and the like. Processing node  700  can also be another network element in a communication system. Further, the functionality of processing node  700  can be distributed over two or more network elements of a communication system. 
     The exemplary systems and methods described herein can be performed under the control of a processing system executing computer-readable codes embodied on a computer-readable recording medium or communication signals transmitted through a transitory medium. The computer-readable recording medium is any data storage device that can store data readable by a processing system, and includes both volatile and nonvolatile media, removable and non-removable media, and contemplates media readable by a database, a computer, and various other network devices. 
     Examples of the computer-readable recording medium include, but are not limited to, read-only memory (ROM), random-access memory (RAM), erasable electrically programmable ROM (EEPROM), flash memory or other memory technology, holographic media or other optical disc storage, magnetic storage including magnetic tape and magnetic disk, and solid state storage devices. The computer-readable recording medium can also be distributed over network-coupled computer systems so that the computer-readable code is stored and executed in a distributed fashion. The communication signals transmitted through a transitory medium may include, for example, modulated signals transmitted through wired or wireless transmission paths. 
     The above description and associated figures teach the best mode of the invention. The following claims specify the scope of the invention. Note that some aspects of the best mode may not fall within the scope of the invention as specified by the claims. Those skilled in the art will appreciate that the features described above can be combined in various ways to form multiple variations of the invention, and that various modifications may be made to the configuration and methodology of the exemplary embodiments disclosed herein without departing from the scope of the present teachings. Those skilled in the art also will appreciate that various features disclosed with respect to one exemplary embodiment herein may be used in combination with other exemplary embodiments with appropriate modifications, even if such combinations are not explicitly disclosed herein. As a result, the invention is not limited to the specific embodiments described above, but only by the following claims and their equivalents.