Abstract:
Aspects of the disclosure provide a method for power reduction in an electronic device. The method includes determining a local timer value corresponding to an idle time for the electronic device to stay in an idle mode. The electronic device is registered to a service provider to provide service to the electronic device. Further, the method includes starting, upon entering the idle mode, a specific timer with the local timer value, and another timer to track a next update time for the electronic device to update tracking area to the service provider for maintaining the electronic device to be registered to the service provider, exiting the idle mode and entering the power saving mode when the specific timer expires, exiting the power saving mode when the other timer expires, and updating the tracking area to the service provider to keep the electronic device being registered to the service provider.

Description:
INCORPORATION BY REFERENCE 
       [0001]    This present disclosure claims the benefit of U.S. Provisional Application No. 62/234,863, “Device local Power Saving Mode Activation in case network does lack support for Power saving mode” filed on Sep. 30, 2015, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
         [0003]    Power consumption is one of the dominant concerns for an electronic device that is a battery-powered. For example, machine type communication devices, such as wireless sensors, and the like are used to keep track of real-time information, such as temperature, rainfall, and the like. In an example, the machine type communication devices are battery powered, and can seldom-or never be recharged, thus power consumption is crucial to extend the battery life and the device life. 
       SUMMARY 
       [0004]    Aspects of the disclosure provide a method for power reduction in an electronic device. The method includes determining, by the electronic device, a local timer value corresponding to an idle time for the electronic device to stay in an idle mode before entering a power saving mode. The electronic device is registered to a service provider to provide service to the electronic device. Further, the method includes starting, upon entering the idle mode, a specific timer with the local timer value, and another timer to track a next update time for the electronic device to update tracking area to the service provider for maintaining the electronic device to be registered to the service provider, exiting the idle mode and entering the power saving mode when the specific timer expires, exiting the power saving mode when the other timer expires, and updating the tracking area to the service provider to keep the electronic device being registered to the service provider. 
         [0005]    To determine, by the electronic device, the local timer value corresponding to the idle time for the electronic device to stay in the idle mode before entering the power saving mode, the method includes determining an availability of a timer value provided by the service provider for the electronic device to stay in the idle mode, and determining, by the electronic device, the local timer value when the timer value is not available. 
         [0006]    To determine the availability of the timer value provided by the service provider for the electronic device to stay in the idle mode, the method includes transmitting a request to the service provider to request an activation of the power saving mode from the service provider, and determining whether the timer value exists in a response from the service provider. 
         [0007]    In an example, the method includes transmitting an attach request that includes a proposed timer value corresponding to a proposed idle time for the electronic device to stay in the idle mode, and determining whether an attach accept message includes the timer value provided by the service provider. In another example, the method includes transmitting a tracking area update that includes a proposed timer value corresponding to a proposed idle time for the electronic device to stay in the idle mode, and determining whether a tracking area update accept message includes the timer value provided by the service provider. 
         [0008]    In an example, the method includes shutting down at least one of paging reception, measurement, and cell selection operations in the power saving mode. 
         [0009]    In an embodiment, the method includes determining the local timer value corresponding to the idle timer based on attributes of the electronic device. 
         [0010]    Aspects of the disclosure provide an apparatus that includes a transceiver circuit and a baseband processing circuit. The transceiver circuit is configured to receive and transmit wireless signals that register the apparatus to a service provider. The baseband processing circuit is configured to determine a local timer value corresponding to an idle time for the apparatus to stay in an idle mode before entering a power saving mode, start, upon the apparatus entering the idle mode, a specific timer with the local timer value, and another timer to track a next update time for the electronic device to update tracking area to the service provider for maintaining the apparatus to be registered to the service provider, control the apparatus to exit the idle mode and enter the power saving mode when the specific timer expires, control the apparatus to exit the power saving mode when the other tinier expires and generate a tracking area update message for the transceiver circuit to transmit to the service provider to keep the apparatus being registered to the service provider. 
         [0011]    Aspects of the disclosure provide a non-transitory computer readable medium storing program instructions for causing a processor to execute operations for power reduction in an electronic device. The operations include determining a local timer value corresponding to an idle time for the electronic device to stay in an idle mode before entering a power saving mode. The electronic device is registered to a service provider to provide service to the electronic device. The operations further include starting, upon entering the idle mode, a specific timer with the local timer value, and another timer to track a next update time for the electronic device to update tracking area to the service provider for maintaining the electronic device to be registered to the service provider, controlling the electronic device to exit the idle mode and enter the power saving mode when the specific timer expires, controlling the electronic device to exit the power saving mode when the other timer expires, and updating the tracking area to the service provider to keep the electronic device being registered to the service provider. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Various embodiments of this disclosure that are proposed as examples will be described in detail with reference to the following figures, wherein like numerals reference like elements, and wherein: 
           [0013]      FIG. 1  shows a diagram of a communication system  100  according to an embodiment of the disclosure; and 
           [0014]      FIG. 2  shows a flow chart outlining a process  100  according to an embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0015]      FIG. 1  shows a diagram of a communication system  100  according to an embodiment of the disclosure. The communication system  100  includes an electronic device  110  that has established a connection with a service provider network  101 . The electronic device  110  has a power saving mode, and generally relies on timing information provided from the service provider network  101  to enter/exit the power saving mode without losing the connection with the service provider network  101 . According to the disclosure, when the timing information from the service provider network  101  is not available, the electronic device  100  is configured to locally determine timing information that can be used to enter/exit the power saving mode without losing the connection with the service provider network  101 , and then to use the timing information to enter/exit the power saving mode to save power. 
         [0016]    The service provider network  101  can be any suitable service provider network, such as mobile service provider network, wireless communication service provider, and the like. In an embodiment, the service provider network  101  is a mobile service provider network  101  that can be implemented using any suitable wireless communication technology, such as third generation ( 3 G) mobile network technology, fourth generation ( 4 G) mobile network technology, fifth generation ( 5 G) mobile network technology, global system for mobile communication (GSM), long-term evolution (LTE), and the like. The service provider network  101  includes a plurality of nodes, such as interface nodes  102 , core nodes  105 , and the like that are coupled together by any suitable network technology, such as wired, wireless, fiber optical network, and the like. 
         [0017]    In an example, the interface nodes  102 , such as base transceiver stations, Node Bs, evolved Node Bs, and the like, include hardware components and software components configured to enable wireless communications between the interface nodes and electronic devices, such as the electronic device  110 , and the like that has subscribed services provided by the service provider network  101 . Further, in the example, the core nodes  105  include hardware components and software components to form a backbone to manage and control the services provided by the service provider network  101 . 
         [0018]    The electronic device  110  can be any suitable electronic device. In an example, the electronic device  110  is a terminal device used by an end-user (user equipment) for mobile telecommunication, such as a cell phone, a smart phone, a tablet computer, and the like. In another example, the electronic device  110  is a machine type communication device, such as a wireless sensor, and the like. 
         [0019]    According to an aspect of the disclosure, the electronic device  110  is configured to perform suitable procedure to register to the service provider network  101 . When the electronic device  110  is registered to the service provider network  101 , the service provider network  101  allocates resources, such as memory resource, timer resource, frequency resource, channel resource, and the like for communication with the electronic device  110 . The electronic device  110  can communicate with the service provider network  101  using the allocated resources. When the electronic device  110  loses the registered status with the service provider network  101 , the electronic device  110  need to perform the suitable procedure again to be registered with the service provider network  101 . 
         [0020]    According to an aspect of the disclosure, the electronic device  110  is a battery-powered device. The electronic device  110  is configured to have a plurality of operation modes, such as a normal mode, an idle mode, a power saving mode (PSM), and the like that have different levels of power consumption. For example, the power saving mode has the least power consumption among the operation modes. The electronic device  110  is configured to increase opportunities to enter the power saving mode to save power, and increase battery life. 
         [0021]    In an embodiment, the power saving mode relies on information provided by the service provider network  101  to keep the electronic device  110  to be registered in the power saving mode. When the information provided by the service provider network  101  is not available, the electronic device  110  is configured to determine locally the information that can keep the electronic device  110  to be registered in the power saving mode, and use the information to enter/exit the power saving mode. 
         [0022]    Specifically, in the  FIG. 1  example, the electronic device  110  includes a transceiver circuit  120  and a baseband processing circuit  130  coupled together as shown in  FIG. 1 . In the example, the transceiver circuit  120  is coupled to an antenna  111 , and includes a transmitting circuit  121 , a receiving circuit  122 , and a measurement circuit  123 . 
         [0023]    The transceiver circuit  120  is configured to receive and transmit wireless signals. For example, the receiving circuit  122  is configured to generate electrical signals in response to captured electromagnetic waves by the antenna  111 , process the electrical signals to extract digital streams from the electrical signals. In an example, the transmitting circuit  121  is configured to receive digital streams, such as management frames, data frames, and the like from for example the baseband processing circuit  130 , generate radio frequency (RF) signals to carry the digital streams, and emit electromagnetic waves in the air via the antenna  111  to transmit wireless signals that carry the digital streams. The measurement circuit  123  is configured to perform measurements, such as received signal strength measurement, and the like. 
         [0024]    The baseband processing circuit  130  is configured to perform various processing in baseband. The baseband processing circuit  130  can be implemented using any suitable technology. In an embodiment, the baseband processing circuit  130  is implemented using pure circuits. In another embodiment, the baseband processing circuit  150  is implemented using a processor (not shown) and memory circuit (not shown). The memory circuit is configured to store data and software instructions. The processor is configured to execute software instructions to process data. 
         [0025]    According to an aspect of the disclosure, the electronic device  110  can be configured to have multiple operation modes of different power consumption. For example, when the electronic device  110  is configured in the normal mode, the transmitting circuit  121 , the receiving circuit  122 , the measurement circuit  123  and the baseband processing circuit  130  are actively in operation, thus the electronic device  110  consumes a relatively large amount of power. 
         [0026]    When the electronic device  110  is in the idle mode, the transmitting circuit  121  is powered off in an example to reduce power consumption. In the idle mode, the electronic device  110  still performs certain operations, such as paging reception operation, measurement operation, cell re-selection operation, and the like. For example, the receiving circuit  122  is still active and receives and processes for example paging signals; the measurement circuit  123  is still active and measures for example received signal strength; and the baseband processing circuit  130  is active and performs, for example, cell reselection operations based on the received paging signals and the measurements of the received signal strength. 
         [0027]    When the electronic device  110  is in the power saving mode, the certain operations, such as paging reception operation, measurement operation, cell re-selection operation, are shut off to save more power. For example, in the power saving mode, the transmitting circuit  121 , the receiving circuit  122  and the measurement circuit  123  are powered off. In addition, in an example, the baseband processing circuit  130  can be configured to reduce power consumption. For example, a portion of the baseband processing circuit  130  can be powered off 
         [0028]    In the  FIG. 1  example, the baseband processing circuit  130  includes a mode controller  140 , a plurality of timers  161 - 163 , and a communication controller  150  coupled together as shown in  FIG. 1 . The baseband processing circuit  130  can include other suitable components (not shown). 
         [0029]    The communication controller  150  is configured to manage communication with the service provider network  101 . In an embodiment, the communication controller  150  is configured to manage communication according to a telecommunication technical standard, such as standards developed by the 3rd generation partnership project (3GPP) unites telecommunications standard development organizations. For example, the communication controller  150  is configured to have an access stratum (AS) functional layer that is responsible for carrying information between the electronic device  110  and the service provider network  101  (e.g., the interface nodes  102 ) using wireless signals, and have a non-access stratum (NAS) functional layer that is responsible for managing the establishment of communication and for maintaining continuous communications between the electronic device  110  and the service provider network  101  (e.g., core nodes  105 ). 
         [0030]    The communication controller  150  can provide information to the transceiver circuit  120  and can receive information from the transceiver circuit  120 . The transceiver circuit  120  can be configured according to the operations of the communication controller  150 . For example, when the communication controller  150  is configured to stop transmitting operations (uplink) of the AS functional layer operations in the idle mode, the transmitting circuit  121  can be powered off When the communication controller  150  is configured to stop receiving operations (downlink) of the AS functional layer operations in the power saving mode, the receiving circuit  122  and the measurement circuit  123  can be powered off In an example, the communication controller  150  explicitly provides control signals to power up/down the respective circuits in the transceiver circuit  120 . In another example, the communication controller  150  provides information that is indicative of power controls to the respective circuits in the transceiver circuit  120 , and accordingly the transceiver circuit  120  can generate control signals to power up/down the respective circuits in the transceiver circuit  120 . 
         [0031]    The mode controller  140  is configured to control the timers  161 - 163 , and provide information to the communication controller  150  according to operations of the timers  161 - 163 . For example, the mode controller  140  can set a timer value to a timer, and start the timer; when the timer expires, the mode controller  140  adjusts operation mode accordingly. 
         [0032]    The timers  161 - 163  are configured to keep track of time. In an embodiment, the timers  161 - 163  are implemented in hardware, such as using circuits. In an example, a timer is implemented using a counter circuit. For example, when a value is set to the timer, the counter circuit is initiated with the value; when the tinier is started, the counter circuit counts down according to a clock signal at a steady pace; and when the counter circuit reaches zero, the tinier expires. 
         [0033]    In the  FIG. 1  example, the timer  161  (T 3412  timer) is configured to track time for periodic tracking area update, the tinier  162  (T 3324  timer) is configured to track time for the idle time, and the timer  163  is configured to track time for locally determined idle time. 
         [0034]    In an example, when the electronic device  110  registers with the service provider network  101  and establishes a communication with the service provider network  101 , the electronic device  110  performs periodic tracking area update to keep the registered status with the service provider network  101 . The period for tracking area update is referred as periodic tracking area update period. The tracking area update allows the electronic device  110  to periodically notify the availability of the electronic device  110  to the service provider network  101  for the service provider network  101  to maintain the electronic device  110  to be registered. For example, in the LTE technology, the service provider network  101  locates the electronic device  110  in the units of tracking areas for the purpose of paging. A tracking area includes a single cell or a plurality of cells. The electronic device  110  periodically notifies the tracking area where the electronic device  110  is located. The service provider network  101  maintains NAS connection over a reachable time that is based on the tracking area update period. In an example, the core nodes  105  allocates a reachable timer (not shown) corresponding to the electronic device  110 . The reachable tinier is set with a reachable time that is longer than the periodic tracking area update period, such as a sum of the periodic tracking area update period and four additional minutes, and keeps track of time for next tracking area update. When the reachable tinier expires, and the service provider network  101  does not receive tracking area update from the electronic device  110 , the electronic device  110  may lose the NAS connection, and may need to perform a communication establishment procedure again with the service provider network  101  to register to the service provider network  101  again in order to receive the service provided by the service provider network  101 . 
         [0035]    In the  FIG. 1  example, the timer  161  in the electronic device  110  tracks the time for a next periodic tracking area update. In an example, when the timer  161  expires, the mode controller  140  controls the electronic device  110  to enter the normal mode, the communication controller  150  then provides tracking area update information, and the transceiver circuit  120  transmits wireless signals carrying the tracking area update information. The interface nodes  102  receive the tracking area update information in wireless signals, and the core nodes  105  process the tracking area update information. Thus, the electronic device  110  keeps the NAS connection with the service provider network  110 . 
         [0036]    In the  FIG. 1  example, the timer  162  in the electronic device  110  tracks the time that the electronic device  110  is in the idle mode. In an example, when the timer  162  expires, the mode controller  140  controls the electronic device  110  to exit the idle mode, and to enter the power saving mode to save power. 
         [0037]    In an example, the service provider network  101  supports the power saving mode, and provide suitable timer values to allow the electronic device  110  to have more opportunities to stay in the power saving mode. For example, during operation, when the mode controller  140  determines to change to power saving mode, the communication controller  150  includes a first timer value that is proposed for the timer  162  in a message, such as an attach request, a tracking area update request, and the like to indicate a request to activate the power saving mode from the service provider network  101 . It is noted that, in an example, the communication controller  150  can include a second timer value that is proposed for the timer  161  in the message. In an example, the second timer value is the periodic tracking area update period. 
         [0038]    Then, the transceiver circuit  120  transmits wireless signals carrying the message. The service provider network  101  receives the message, and identifies the request to activate the power saving mode. When the service provider network  101  accepts the request to activate the power saving mode, the service provider network  101  provides a third timer value that is determined for the timer  162  in a response message, such as an attach accept message, a tracking area update accept message, and the like. It is noted that, in an example, the service provider network  101  provides a fourth timer value that is determined for the timer  161  in the response message. 
         [0039]    In an example, the service provider network  101  sets the reachable timer corresponding to the electronic device  110  according to the fourth timer value, such as four minutes in addition to the fourth timer value, and starts the reachable timer. 
         [0040]    It is noted that the third timer value can be the same as the first timer value or can be different from the first timer value, and the fourth timer value can be the same as the second timer value or can be different from the second timer value. 
         [0041]    In an example, when the electronic device  110  receives the response message from the service provider network  101 , the electronic device  110  extracts the timer values in the response message, and sets timers according to the timer values in the response message. In an example, the mode controller  140  sets the timer  162  to have the third timer value, sets the timer  161  to have the fourth timer value, starts the timer  161  and the timer  162 , and controls the electronic device  110  to enter the idle mode. When the timer  162  expires, the mode controller  140  controls the electronic device  110  to enter the power saving mode; and when the timer  161  expires, the mode controller  140  controls the electronic device  110  to exit the power saving mode and enter the normal mode. Then, the communication controller  150  prepares tracking area update message, and the transceiver circuit  120  transmits wireless signals to carry the tracking area update message. 
         [0042]    According to an aspect of the disclosure, the electronic device  110  is not able to receive the timer values provided by the service provider network  101 . In an example, the service provider network  101  does not support the power saving mode, and does not include the third timer value in the response message. 
         [0043]    According to the disclosure, when the electronic device  110  does not receive the third timer value, the mode controller  140  can determine a local timer value, and set a timer, such as the timer  163  according to the local timer value. In an embodiment, the mode controller  140  determines the local timer value based on attributes of the electronic device  110 , such as applications that are running in the electronic device  110 , battery remaining level, and the like. In an example, the local timer value is zero to aggressively save power. Generally, the local tinier value is smaller than the periodic tracking area update period, which is the second timer value for the timer  161 . 
         [0044]    Then, the mode controller  140  sets the timer  161  to have the second timer value, sets the timer  163  to have the local timer value, starts the timer  161  and the timer  163 , and controls the electronic device  110  to enter the idle mode. When the timer  163  expires, the mode controller  140  controls the electronic device  110  to exit the idle mode and enter the power saving mode; and when the timer  161  expires, the mode controller  140  controls the electronic device  110  to exit the power saving mode and enter the normal mode. Then, the communication controller  150  prepares tracking area update message, and the transceiver circuit  120  transmits wireless signals to carry the tracking area update message to the service provider network  101 . 
         [0045]    It is noted that the electronic device  110  can exit the power saving mode due to other triggers, such as a need to send data generated in the electronic device  110 . 
         [0046]      FIG. 2  shows a flow chart outlining a process example  200  according to an embodiment of the disclosure. In an example, the process is executed by the electronic device  110  in  FIG. 1 . The process starts at S 201  and proceeds to S 210 . 
         [0047]    At S 210 , a request to activate a power saving mode from a service provider network is transmitted. In the  FIG. 1  example, the mode controller  140  determines a chance to enter the power saving mode, the communication controller  150  generates a message, such as an attach request, a tracking area update request, and the like to include a first timer value that is proposed for the T 3324  timer (the timer  162 ) to indicate a request to activate the power saving mode. In an example, the message includes a second tinier value that is proposed for the T 3412  timer (the timer  161 ). Then, the transceiver circuit  120  transmits wireless signals carrying the message. 
         [0048]    At S 220 , a response message is received. In the  FIG. 1  example, the service provider network  101  sends an attach accept message in response to the attach request, or sends a tracking area update accept message in response to the tracking area update request. When the service provider network  101  supports the power saving mode operation and accepts the power saving mode, the service provider network  101  provides a third timer value that is determined for the T 3324  timer in the response message. In an example, the response message also includes a fourth timer value that is determined for the T 3412  timer. However, when the service provider network  101  does not support the power saving mode operation, the third timer value for the timer T 3324  is not in the response message. 
         [0049]    At S 230 , the electronic device  110  detects whether the third timer value for the T 3324  timer is in the response message. When the third timer value for the T 3324  is in the response message, the process proceeds to S 240 ; otherwise the process proceeds to S 260 . 
         [0050]    At S 240 , the electronic device  110  enters the idle mode. Further, the mode controller  140  sets the third value to the T 3324  timer, sets the fourth value to the T 3412  timer, and starts the T 3412  timer and the T 3324  timer. 
         [0051]    At S 245 , when the timer T 3324  expires, the electronic device  110  exits the idle mode and enters the power saving mode. 
         [0052]    At S 250 , when the timer T 3412  expires, the electronic device  110  exits the power saving mode. Other suitable triggers can also cause the electronic device  110  to exit the power saving mode. 
         [0053]    At S 260 , the electronic device  110  enters the idle mode. Further, the mode controller  140  determines a local timer value for the Timer X (the timer  163 ), sets the Timer X with the local timer value, sets the T 3412  timer with the periodic tracking area update period, and starts the T 3412  timer and the Timer X. 
         [0054]    At S 265 , when the Timer X expires, the electronic device  110  exits the idle mode and enters the power saving mode. 
         [0055]    At S 270 , when the timer T 3412  expires, the electronic device  110  exits the power saving mode. Other suitable triggers can also cause the electronic device  110  to exit the power saving mode. 
         [0056]    At S 280 , the electronic device  110  enters the normal mode. In the normal mode, the transceiver  120  is powered up and transmits/receives wireless signals that carry various information. When the electronic device  110  finds a change to enter the power saving mode, the process returns to S 210 . 
         [0057]    When implemented in hardware, the hardware may comprise one or more of discrete components, an integrated circuit, an application-specific integrated circuit (ASIC), etc. 
         [0058]    While aspects of the present disclosure have been described in conjunction with the specific embodiments thereof that are proposed as examples, alternatives, modifications, and variations to the examples may be made. Accordingly, embodiments as set forth herein are intended to be illustrative and not limiting. There are changes that may be made without departing from the scope of the claims set forth below.