Abstract:
Embodiments disclosed herein provide systems and methods for adjusting an access channel dormancy timer. In a particular embodiment, a method comprises wirelessly receiving a call request from a wireless communication device. In response to the call request, starting an access channel timer and transferring call set-up signaling to extend the call. If the access channel timer expires before a negative response is received to the call set-up signaling, then allocating a wireless access channel to the wireless device for the call. If the negative response is received before the timer expires, then denying the wireless access channel to the wireless device for the call. If the negative response is received after the timer expires, then releasing the wireless access channel from the wireless device. If a positive response is received before the timer expires, then allocating the wireless access channel to the wireless device for the call.

Description:
TECHNICAL BACKGROUND 
     Wireless devices, such as cellular phones, communicate with other systems and devices via wireless communication networks. A wireless device connects with a wireless communication network by exchanging communications with an access node for that wireless network, such as a base station. The wireless device communicates with the access node using both control and access channels. Control channels are used to exchange control messages with connected wireless devices and each control channel may be shared among multiple wireless devices. Access channels are used for more bandwidth intensive communications, such as user voice and data communications, and each access channel can be used by one wireless device at a time. 
     Each access node on a wireless network has a limited number of access channels that the access node can allocate to wireless devices that are connected to the access node. As more access channels are allocated to various wireless devices the number of access channels available for allocation to other wireless devices is reduced. If communications are not being exchanged by a wireless device on an access channel, then that access channel does not need to be allocated to that wireless device and can be available for allocation to a wireless device that will exchange communications. 
     OVERVIEW 
     Embodiments disclosed herein provide systems and methods for adjusting an access channel dormancy timer. In a particular embodiment, a method comprises wirelessly receiving a call request from a wireless communication device. In response to the call request, the method provides starting an access channel timer and transferring call set-up signaling to extend the call. If the access channel timer expires before a negative response is received to the call set-up signaling, then allocating a wireless access channel to the wireless communication device for the call. If the negative response is received to the call set-up signaling before the access channel timer expires, then denying the wireless access channel to the wireless communication device for the call. If the negative response is received to the call set-up signaling after the access channel timer expires, then releasing the wireless access channel from the wireless communication device. If a positive response is received to the call set-up signaling before the access channel timer expires, then allocating the wireless access channel to the wireless communication device for the call. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a wireless communication system. 
         FIG. 2  illustrates the operation of a wireless communication system. 
         FIG. 3  illustrates a wireless communication system. 
         FIG. 4  is a sequence diagram illustrating the operation of a wireless communication system. 
         FIG. 5  is a sequence diagram illustrating the operation of a wireless communication system. 
         FIG. 6  is a sequence diagram illustrating the operation of a wireless communication system. 
         FIG. 7  is a sequence diagram illustrating the operation of a wireless communication system. 
         FIG. 8  illustrates a wireless access node. 
     
    
    
     DETAILED DESCRIPTION 
     The following description and associated figures teach the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects of the best mode may be simplified or omitted. 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. Thus, those skilled in the art will appreciate variations from the best mode that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents. 
       FIG. 1  illustrates wireless communication system  100 . Wireless communication system  100  includes wireless communication device  101 , wireless access node  102 , and wireless communication network  103 . Wireless communication device  101  and wireless access node  102  communicate over wireless link  110 . Wireless access node  102  and wireless network  103  communicate over communication link  111 . 
     In operation, wireless device  101  communicates with other devices and systems via access node  102  and wireless network  103 . When exchanging communications other than control communications, such as voice and data communications, wireless device  101  requires an access channel provided by access node  102 . Once wireless device  101  is assigned an access channel, then wireless device  101  and access node  102  can exchange communications over that access channel. 
     Access node  102  has a limited number of access channels to allocate to connected wireless devices, such as wireless device  101 . Thus, when no communications are being exchanged with wireless device  101 , access node  102  tries to not allocate an access channel to wireless device  101 . Not allocating an access channel to wireless device  101  during periods where no communications are being exchanged on the access channel allows access node  102  to allocate that access channel to another device that needs the access channel for communications. Therefore, an access channel is assigned to wireless device  101  for less time during periods of communication inactivity increases the time that the access channel is available to be assigned to another device. 
       FIG. 2  illustrates the operation of wireless communication system  100 . Access node  102  receives a call request from wireless device  101  (step  200 ). The call request may be for a voice call, video call, VoIP call, application data, or any other type of request for communications that would use an access channel from access node  102 . The call may be received over a control channel of access node  102  that is used for control communications between access node  102  and wireless device  101 , as well as other wireless devices connected to access node  102 . 
     After receiving the call request from wireless device  101 , access node  102  starts an access channel timer (step  202 ). The access channel timer indicates when an access channel should be allocated to wireless device  101  for the communications indicated by the call request. The access channel timer may take various forms. In one example, the access channel timer may be a countdown timer that begins with a set time value then, upon starting, counts down to zero. Alternatively, the timer may start at zero then count up to a set value. In another example, the timer may be a continuously running timer where access node  102  notes the time indicated by the timer after receiving the call request then monitors the timer for a set time increment. The access channel timer may be set to any length of time. 
     Access node  102  then transfers call set-up signaling to extend the call (step  204 ). The call set-up signaling may by any type of signaling or message that will allow the call to reach a destination indicated by the call. For example, if the call is a voice call then the destination may be a phone or wireless device. The call set-up signaling may be transferred to other systems and devices on wireless network  103  but may also be transferred from wireless network  103  to devices and systems on other communication networks. 
     In some embodiments access node  102  may determine a destination for the call request. The destination may be a device or system that is indicated by the call request, such as a phone number, address, or other type of identifier. The call set-up signaling may transfer the call request to a next system in a chain of systems leading to the destination or directly to the destination itself. Alternatively, the call set-up signaling may be a paging signal to the destination or may indicate to another system that the destination should receive a paging signal. 
     As stated above, the access channel timer may be set to any length of time. However, in some embodiments, the length of time may be an average of past times that wireless device  101 , or other devices on access node  102  or wireless network  103 , waited before receiving a response to the call set-up signaling. Otherwise, the access timer may be set to a time that strikes a balance between keeping an access channel available for other wireless devices while also providing wireless device  101  with an access channel for the call request in a timely manner. 
     If the access channel timer expires, or otherwise indicates that an amount of time has passed, before access node  102  receives a negative response to the call set-up signaling, then access node  102  allocates a wireless access channel to wireless device  101  for the call (step  206 ). The negative response may be a message, or some other type of signaling, that indicates that the call request cannot be completed. The negative response may be received the destination indicated by the call request or by a system or device in the network chain leading to the destination. For example, the destination for the call request may be a wireless device on another wireless network. If that wireless network is unable to reach the device then the wireless network may transfer a message back to access node  102  that the destination cannot be reached. 
     If the negative response is received to the call set-up signaling after the access channel timer expires, then access node  102  releases the wireless access channel from wireless device  101  (step  210 ). In this case, the access channel was already allocated to wireless device  101  upon the expiration of the access channel timer as described in the preceding example. Thus, when a negative response is received after the access channel has been allocated to wireless device  101 , then the access channel should be released because no communications will be exchanged on the access channel with regards to the call request. After being released the access channel is now available to be assigned to other wireless devices communicating with access node  102 . 
     Additionally, if the negative response is received to the call set-up signaling before the access channel expires, then access node  102  denies the wireless access channel to wireless device  101  (step  208 ). The access channel is denied because no communications will be exchanged on the access channel with regards to the call request and the access channel remains available for assignation to other wireless devices. 
     However, if a positive response is received to the call set-up signaling before the access channel timer expires, then access node  102  allocates the wireless access channel to the wireless communication device for the call (step  206 ). The positive response may be a message, or some other type of signaling, that indicates that the destination for the call request is available to be notified of the call request. The access channel is allocated to wireless device  101  because once the destination can be notified of the call request then it is more likely that the access channel will be needed for communications between wireless device  101  and the destination. 
     Therefore, the above discussion allows for access node  102  to wait before assigning an access channel to wireless device  101 . This allows the access channel to remain unassigned for a longer period of time, which will allow the access channel to be assigned to another wireless device if needed. 
     In some embodiments, if access node  102  receives a negative response, then access node  102  transfers a message over the control channel to wireless device  101  indicating that the call request cannot be completed. Wireless device  101  may then notify the user of wireless device  101  accordingly. 
     In other embodiments, if access node  102  receives a positive response, then access node  102  establishes a call between wireless device  101  and the destination for the call over the access channel provided by access node  102 . 
     Referring back to  FIG. 1 , wireless communication device  101  comprises Radio Frequency (RF) communication circuitry and an antenna. The RF communication circuitry typically includes an amplifier, filter, modulator, and signal processing circuitry. Wireless communication device  101  may also include a user interface, memory device, software, processing circuitry, or some other communication components. Wireless communication device  101  may be a telephone, computer, e-book, mobile Internet appliance, wireless network interface card, media player, game console, or some other wireless communication apparatus—including combinations thereof. 
     Wireless access node  102  comprises RF communication circuitry and an antenna. The RF communication circuitry typically includes an amplifier, filter, RF modulator, and signal processing circuitry. Wireless access node  102  may also comprise a router, server, memory device, software, processing circuitry, cabling, power supply, network communication interface, structural support, or some other communication apparatus. Wireless access node  102  could be a base station, Internet access node, telephony service node, wireless data access point, or some other wireless communication system—including combinations thereof. 
     Wireless communication network  103  is a communication network that comprises telephony switches, wireless access nodes, Internet routers, network gateways, computer systems, communication links, or some other type of communication equipment—including combinations thereof. 
     Wireless link  110  uses the air or space as the transport media. Wireless link  110  may use various protocols, such as Code Division Multiple Access (CDMA), Evolution Data Only (EVDO), Worldwide Interoperability for Microwave Access (WIMAX), Global System for Mobile Communication (GSM), Long Term Evolution (LTE), Wireless Fidelity (WIFI), High Speed Packet Access (HSPA), or some other wireless communication format. Communication link  111  uses metal, glass, air, space, or some other material as the transport media. Communication link  111  could use various communication protocols, such as Time Division Multiplex (TDM), Internet Protocol (IP), Ethernet, communication signaling, CDMA, EVDO, WIMAX, GSM, LTE, WIFI, HSPA, or some other communication format—including combinations thereof. Communication link  111  could be a direct link or may include intermediate networks, systems, or devices. 
       FIG. 3  illustrates wireless communication system  300 . Wireless communication system  300  includes wireless communication device  301 , base station  304 , wireless communication network  303 , control system  304 , and destination  305 . Wireless device  301  and base station  302  communicate over wireless link  310 . Base station  302  and wireless network  303  communicate over link  311 . Wireless network  303  and destination  305  communicate over link  312 . 
     Communication control system  304  comprises a computer system and communication interface. Communication control system  304  may also include other components such a router, server, data storage system, and power supply. Communication control system  304  may reside in a single device or may be distributed across multiple devices. Communication control system  304  is shown internally to base station  302 , but system  304  could be an independent system, such as an MSC, or integrated into another system of wireless network  303 . 
     Destination  305  comprises a device or system that is capable of communicating with wireless device  301 . Destination  305  may be a wireless communication device, wireline communication device, application system, or any other type of system or device. Destination  305  may be a system or device on wireless network  303  but may also be connected to wireless network  303  through other networks. 
       FIG. 4  is a sequence diagram illustrating the operation of wireless communication system  300 . Wireless device  301  transfers a call request to base station  302  over a control channel used to exchange control communications between base station  302  and connected wireless devices. The call request indicates that wireless device  301  intends to establish a voice call with destination  305 . Upon receiving the call request control system  304  starts an access channel timer. The access channel timer starts at a preset value and begins to count down to zero, which will indicate to control system  304  that an access channel should be allocated to wireless device  301 . 
     Control system  304  transfers a locate message to wireless device  301  over the control channel. The locate message indicates to wireless device  301  that control system  304  is attempting to locate and contact destination  305 . Upon receiving the locate message, wireless device  301  indicates to a user of wireless device  301  that destination  305  is being located. The indication may be in the form of a ring back tone or some other form of audible or visual message capable of conveying that destination  305  is being located. 
     Control system  304  then searches for destination  305  as indicated by the call request. The search may find the location of destination  305  on wireless network  303 , or some other network, or may find the next step in a chain of systems or networks leading to destination  305 , such as a public switched telephone network. Upon finding destination  305 , control system  304  transfers a paging signal to destination  305 . In this example, before receiving a response to the page from destination  305 , the access channel timer reaches zero. In response to the expiration of the access channel timer, control system allocates an access channel for wireless device  301  and base station  302 . The wireless access channel is used to exchange communications between wireless device  301  and destination  305  if and when destination  305  accepts the call from wireless device  301 . 
       FIG. 5  is a sequence diagram illustrating the operation of wireless communication system  300 . Wireless device  301  transfers a call request to base station  302  over a control channel used to exchange control communications between base station  302  and connected wireless devices. The call request indicates that wireless device  301  intends to establish a voice call with destination  305 . Upon receiving the call request control system  304  starts an access channel timer. The access channel timer starts at a preset value and begins to count down to zero, which will indicate to control system  304  that an access channel should be allocated to wireless device  301 . 
     Control system  304  transfers a locate message to wireless device  301  over the control channel. The locate message indicates to wireless device  301  that control system  304  is attempting to locate and contact destination  305 . Upon receiving the locate message, wireless device  301  indicates to a user of wireless device  301  that destination  305  is being located. The indication may be in the form of a ring back tone or some other form of audible or visual message capable of conveying that destination  305  is being located. 
     Control system  304  then searches for destination  305  as indicated by the call request. The search may find the location of destination  305  on wireless network  303 , or some other network, or may find the next step in a chain of systems or networks leading to destination  305 , such as a public switched telephone network. Upon finding destination  305 , control system  304  transfers a paging signal to destination  305 . In this example, control system  304  receives a negative response indicating that destination  305  cannot be notified of the call or that destination  305  declined the call. Due to the negative response, control system  304  denies allocation of an access channel to wireless device  301  because wireless device  301  and destination  305  will not need the access channel to exchange communications. After receiving a negative response, the expiration of the access channel timer does not matter because control system  304  no longer needs to allocate an access channel to wireless device  301  for the communications related to the call request. Thus, the timer may be reset for future use or simply ignored. 
       FIG. 6  is a sequence diagram illustrating the operation of wireless communication system  300 . Wireless device  301  transfers a call request to base station  302  over a control channel used to exchange control communications between base station  302  and connected wireless devices. The call request indicates that wireless device  301  intends to establish a voice call with destination  305 . Upon receiving the call request control system  304  starts an access channel timer. The access channel timer starts at a preset value and begins to count down to zero, which will indicate to control system  304  that an access channel should be allocated to wireless device  301 . 
     Control system  304  transfers a locate message to wireless device  301  over the control channel. The locate message indicates to wireless device  301  that control system  304  is attempting to locate and contact destination  305 . Upon receiving the locate message, wireless device  301  indicates to a user of wireless device  301  that destination  305  is being located. The indication may be in the form of a ring back tone or some other form of audible or visual message capable of conveying that destination  305  is being located. 
     Control system  304  then searches for destination  305  as indicated by the call request. The search may find the location of destination  305  on wireless network  303 , or some other network, or may find the next step in a chain of systems or networks leading to destination  305 , such as a public switched telephone network. Upon finding destination  305 , control system  304  transfers a paging signal to destination  305 . In this example, before receiving a response to the page from destination  305 , the access channel timer reaches zero. In response to the expiration of the access channel timer, control system allocates an access channel for wireless device  301  and base station  302 . The wireless access channel is allocated in anticipation of a positive response being received indicating that destination  305  is being notified about the call request. 
     However, in this example, control system  304  receives a negative response indicating that the destination could not be notified of the call request or has denied the call request. Due to the negative response, wireless device  301  will no longer need the access channel for communications related to the call request. Therefore, control system  304  releases the access channel that was previously allocated to wireless device  301  so that the access channel can be used for other wireless devices. 
       FIG. 7  is a sequence diagram illustrating the operation of wireless communication system  300 . Wireless device  301  transfers a call request to base station  302  over a control channel used to exchange control communications between base station  302  and connected wireless devices. The call request indicates that wireless device  301  intends to establish a voice call with destination  305 . Upon receiving the call request control system  304  starts an access channel timer. The access channel timer starts at a preset value and begins to count down to zero, which will indicate to control system  304  that an access channel should be allocated to wireless device  301 . 
     Control system  304  transfers a locate message to wireless device  301  over the control channel. The locate message indicates to wireless device  301  that control system  304  is attempting to locate and contact destination  305 . Upon receiving the locate message, wireless device  301  indicates to a user of wireless device  301  that destination  305  is being located. The indication may be in the form of a ring back tone or some other form of audible or visual message capable of conveying that destination  305  is being located. 
     Control system  304  then searches for destination  305  as indicated by the call request. The search may find the location of destination  305  on wireless network  303 , or some other network, or may find the next step in a chain of systems or networks leading to destination  305 , such as a public switched telephone network. Upon finding destination  305 , control system  304  transfers a paging signal to destination  305 . In this example, control system  304  receives a positive response indicating that destination  305  is being notified of the call request. Due to the positive response, control system  304  allocates an access channel to wireless device  301  because there is now increased likelihood that the call will be accepted by destination  305  and that communications will be exchanged between wireless device  301  and destination  305 . 
       FIG. 8  illustrates wireless access node  800 . Access node  800  is an example of wireless access node  102 , although access node  102  may use alternative configurations. Access node  800  comprises wireless communication interface  801 , communication interface  802 , and processing system  803 . Processing system  803  is linked to communication interface  801  and user interface  802 . Processing system  803  includes processing circuitry  805  and memory device  806  that stores operating software  807 . 
     Wireless communication interface  801  comprises RF communication circuitry and an antenna. The RF communication circuitry typically includes an amplifier, filter, RF modulator, and signal processing circuitry. Wireless communication interface  801  may also include a memory device, software, processing circuitry, or some other communication device. Wireless communication interface  801  may use various protocols, such as CDMA, GSM, UMTS, HSPA, EV-DO, EV-DO rev. A, 3GPP LTE, WiMAX, Wi-Fi, or some other wireless communication format. 
     Network communication interface  802  comprises components that communicate over communication links, such as network cards, ports, RF transceivers, processing circuitry and software, or some other communication devices. Network communication interface  802  may be configured to communicate over metallic, wireless, or optical links. Network communication interface  802  may be configured to use TDM, IP, Ethernet, optical networking, wireless protocols, communication signaling, or some other communication format—including combinations thereof. 
     Processing circuitry  805  comprises microprocessor and other circuitry that retrieves and executes operating software  807  from memory device  806 . Memory device  806  comprises a disk drive, flash drive, data storage circuitry, or some other memory apparatus. Operating software  807  comprises computer programs, firmware, or some other form of machine-readable processing instructions. Operating software  807  may include an operating system, utilities, drivers, network interfaces, applications, or some other type of software. When executed by circuitry  805 , operating software  807  directs processing system  803  to operate access node  800  as described herein. 
     In particular, operating software  807  directs processing system  803  to wirelessly receive a call request from a wireless communication device via wireless communication interface  801 . Processing system  803  further, in response to receiving the call request, starts an access channel timer. Communication interface  802  transfers call set-up signaling to extend the call. If the access channel timer expires before a negative response is received to the call set-up signaling, then processing system  803  allocates a wireless access channel to the wireless communication device for the call. If the negative response is received to the call set-up signaling before the access channel timer expires, then processing system  803  denies the wireless access channel to the wireless communication device for the call. If the negative response is received to the call set-up signaling after the access channel timer expires, then processing system  803  releases the wireless access channel from the wireless communication device. If a positive response is received to the call set-up signaling before the access channel timer expires, then processing system  803  allocates the wireless access channel to the wireless communication device for the call. 
     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. As a result, the invention is not limited to the specific embodiments described above, but only by the following claims and their equivalents.