Abstract:
Aspects of the disclosure provide a method for controlling user equipment (UE) to improve user experience. The method includes sensing an environmental condition using a sensor associated with the UE, and governing a communication functionality of the UE based on the sensed environmental condition.

Description:
INCORPORATION BY REFERENCE 
     This application claims the benefit of U.S. Provisional Applications No. 61/294,003, “Elevator Environment Detector” filed on Jan. 11, 2010, and No. 61/419,187, “Controlling Communication System Using Application Sensor Inputs” filed on Dec. 2, 2010, which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     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. 
     Generally, cellular networks include numerous base stations and numerous user equipment (UE) devices, each of which devices communicates at any given time with one or more of the base stations. A pairing between a UE and a base station is periodically evaluated for quality of a communication link, and the pairing is occasionally changed. 
     SUMMARY 
     Aspects of the disclosure provide a method for controlling user equipment (UE) to improve user experience. The method includes sensing an environmental condition using a sensor associated with the UE, and governing a communication functionality of the UE based on the sensed environmental condition. 
     In an embodiment, the method includes sensing a proximity to a human appendage, and controlling a radiation characteristic of the UE for communication based on the sensed proximity. To control the radiation characteristic, in an example, the method includes adjusting respective transmission power of multiple antennas to direct transmission away from a human head when the UE is sensed in a proximity of the human head. In another example, the method includes reducing a radiation power when the UE is sensed in the proximity of the human head. 
     According to an aspect of the disclosure, to sense the environmental condition, the method includes sensing a motion dynamic of the UE. Further, in an example, to govern the communication functionality, the method includes at least one of governing a receiving algorithm based on the sensed motion dynamic, governing a protocol stack operation of the UE based on the sensed motion dynamic, and governing a scan process to search for a servicing base station based on the sensed motion dynamic. 
     In an embodiment, the method further includes re-establishing a communication service with a last servicing base station based on the sensed environmental condition. 
     In an example, the method includes sensing an elevation dynamic of the UE using a gravimeter, and storing the last servicing base station when the sensed elevation dynamic is indicative of the UE being in an elevator. For example, the method includes activating the gravimeter when the UE loses reception from the last servicing base station. 
     To re-establish the communication service with the last servicing base station based on the senses environmental condition, in an example, the method includes re-establishing the communication service with the last servicing base station when the sensed elevation dynamic is indicative of the UE being out of the elevator. In another example, the method includes re-establishing the communication service with the last servicing base station when received signal strength exceeds a threshold. 
     Aspects of the disclosure also provide user equipment (UE) that has improved user experience. The UE includes an environmental sensor module configured to sense an environmental condition of the UE, a wireless communication module configured to perform wireless communication, and a communication controller configured to govern operations of the wireless communication module based on the sensed environmental condition input from the environmental sensor module. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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: 
         FIG. 1  shows a block diagram of user equipment (UE)  101  according to an embodiment of the disclosure; 
         FIGS. 2A and 2B  show block diagrams of a mobile phone  201  during operation according to an embodiment of the disclosure; and 
         FIG. 3  shows a flow chart outlining a process example  300  for governing communication operations based on a sensed environmental condition according to an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       FIG. 1  shows a block diagram of user equipment (UE)  101  according to an embodiment of the disclosure. The UE  101  includes an environmental sensor module  110 , a wireless communication module  120 , and a communication controller  130 . The communication controller  130  is configured to control operations of the wireless communication module  120  based on inputs from the environmental sensor module  110 . In an embodiment, these elements are coupled together as shown in  FIG. 1 . 
     The UE  101  can be any suitable user equipment, such as a mobile phone, a personal data assistant, a handheld device, a laptop computer, a camera, a printer, a media device, and the like. According to an embodiment of the disclosure, the UE  101  is configured to communicate with an access point in a communication network, such as a base station in a cellular telephony network, and the like, to perform mobile communication. 
     The wireless communication module  120  receives signals from the air, and processes the received signals. In addition, the wireless communication module  120  prepares signals for transmission, and transmits the prepared signals into the air. The wireless communication module  120  includes various suitable hardware components and software components. 
     For example, the wireless communication module  120  includes a receiving path (not shown). In an embodiment, the receiving path includes a front-end analog portion that processes the received signals using analog techniques, an analog to digital converter (ADC) that converts the processed signals from analog form to digital form, and digital circuits that process the converted signals using digital techniques. In an example, the front-end analog portion includes a signal quality measurement circuit that measures a signal quality, such as a signal strength of a received signal. 
     The wireless communication module  120  also includes a transmission path (not shown). In an embodiment, the transmission path includes digital circuits to process signals for transmission using digital techniques, a digital to analog converter (DAC) that converts the processed signals from digital form to analog form, and analog circuits that prepare the converted signals for transmission using analog techniques. In an example, the analog circuits include a power amplifier that can be used to adjust signal transmission power. 
     Further, the wireless communication module  120  includes software components, such as communication protocols, scan algorithms, and the like, that are in the form of instruction codes stored in a computer readable medium. The instruction codes can be executed by a processor to perform operations on the received signals, and generate signals for transmission. 
     According to an aspect of the disclosure, the wireless communication module  120  is configured to perform a full scan process or a partial scan process to search for a suitable servicing base station, for example when a quality of a communication link between the UE  101  and a base station falls below a communication link threshold. In an example, the wireless communication module  120  tunes its synchronization to every possible communication link to receive a signal sent by a base station, measure a signal quality, and determines whether the base station is suitable for a servicing base station based on the signal quality. 
     In another example, the wireless communication module  120  includes a list of a subset of base stations, such as neighbor base stations, various available modes with the base stations, and the like. The wireless communication module  120  respectively tunes its synchronization to each neighbor base station on the list, receives a signal to measure a signal quality, and determines whether the neighbor base station is suitable for a servicing base station based on the signal quality. 
     In another example, the wireless communication module  120  receives instructions, for example, from the communication controller  130 , to start scanning from a specific base station. The wireless communication module  120  tunes its synchronization to the specific base station to receive a signal, measures a signal quality, and determines whether the specific base station is suitable for a servicing base station based on the signal quality. 
     According to another aspect of the disclosure, the wireless communication module  120  is able to adjust radiation characteristic for transmission. In an example, the wireless communication module  120  controls the power amplifier to adjust transmission power. In another example, the wireless communication module  120  includes multiple antennas for transmission. The wireless communication module  120  can adjust respective transmission power of the multiple antennas, such that the collective transmission by the multiple antennas has a desired radiation pattern. In another example, the multiple antennas have spatial and/or directional difference, and the wireless communication module  120  selects suitable antennas for transmission. For example, the wireless communication module  120  selects a directional antenna having a desired transmission direction. 
     According to another aspect of the disclosure, the wireless communication module  120  is able to operate according to different wireless communication standards, such as code division multiple access (CDMA), wideband CDMA, long term evolution (LTE), advanced version of LTE (LTE-A), global system for mobile (GSM), WiFi, and the like. The wireless communication module  120  selects a standard, and communicates according to the standard. 
     According to another aspect of the disclosure, the wireless communication module  120  is implemented by a layered architecture, such as a protocol stack, to provide various communication services and to suitably respond to various events. The protocol stack includes various layers. Each layer is configured to perform a portion of the communication services, and is configured to communication with adjacent layers. The operation of the protocol stack, and the operations of the layers can be suitably controlled. 
     The environmental sensor module  110  senses suitable environmental parameters. It is noted that the environmental sensor module  110  can include various sensors to sense various parameters in the environment. The environmental condition is determined based on sensed values from one or more sensors. 
     In an embodiment, the environmental sensor module  110  includes gravimeter (G-sensor) that uses a miniature accelerometer to sense a gravitational field. The gravitational field can be used to detect motion dynamics of the UE  101  in a vertical direction. In an example, the G-sensor senses a gravitational field, and compensates the gravitational field to detect a vertical acceleration of the UE  101 , for example, in an elevator. An integral of the vertical acceleration over time is indicative a vertical velocity of the UE  101 . Further, an integral of the vertical velocity provides a vertical distance traveled by the UE  101 . 
     It is noted that the environmental sensor module  110  can include other suitable accelerometer that senses acceleration in other directions. 
     In another embodiment, the environmental sensor module  110  includes a compass that senses a magnetic field. In an example, the compass provides directional information of the UE  101 . In another embodiment, the environmental sensor module  110  includes a Gyro-sensor that senses spatial movement, such as rotation, and the like. In an example, the Gyro-sensor provides a rotation vector that is indicative of rotation of the UE  101 . 
     In another embodiment, the environmental sensor module  110  includes a global position system (GPS) that provides location and velocity information. In another embodiment, the environmental sensor module  110  includes a humidity sensor that provides humidity in the environment. In another embodiment, the environmental sensor module  110  includes a surrounding temperature sensor that provides an external temperature. In another embodiment, the environmental sensor module  110  includes a barometric sensor that provides pressure and altitude measurement. In another embodiment, the environmental sensor module  110  includes a radar that detects a surrounding metal structure. 
     It is noted that the environmental sensor module  110  can include other suitable sensors, such as proximity sensor, video sensor, optical sensor, and the like. 
     The communication controller  130  receives inputs from the environmental sensor module  110 , and determines one or more environmental conditions based on the inputs. Based on the environmental conditions, the communication controller  130  controls operations of the wireless communication module  120 . 
     In an embodiment, the communication controller  130  provides the environmental information to the protocol stack to govern the operation of the protocol stack. The protocol stack delivers the environmental information to suitable layers, causes the suitable layers of the wireless communication module  120  to suitably respond to the environmental information. For example, the layers suitably adjust communication services based on the environmental information. In an example, an LTE stack includes an L3 layer of radio resource control (RRC) protocol that performs signal strength measurement, cell reselection, handover, security, integrity services, and the like. The L3 layer may perform differently according to the environmental information. In an example, when the environmental information indicates that the UE  101  is in an elevator, the L3 layer holds on cell reselection and handover services in response to relatively low received signal strength, until the UE  101  exits the elevator. However, when the environmental information indicates that the UE  101  is in an open area, the L3 layer performs cell reselection and handover services in response to relatively low received signal strength. 
     In another embodiment, the communication controller  130  receives inputs from the environmental sensor  110  to determine a proximity of the UE  101  to a human appendage, such as a human hand, a human head, and the like. Further, the communication controller  130  controls the operation of the wireless communication module  120  based on the determined proximity of the UE  101 . In an example, the communication controller  130  determines that the UE  101  is in a proximity of a user&#39;s head when the user puts the UE  101  near his ear to listen to an internal speaker of the UE  101 . The communication controller  130  controls the wireless communication module  120  to adjust radiation characteristics, such as adjusting respective transmission power of multiple antennas, selecting an antenna with a directional radiation pattern, reducing transmission power, and the like, to minimize radiation to the user. It is noted that, in an embodiment, by adjusting radiation characteristics, the UE  101  is controlled so as to emit radiation in a pattern that is less detrimental to the user, although this comes at a cost of a sub-optical, but nevertheless acceptable, communication link with the base station. 
     In another embodiment, the communication controller  130  receives inputs from the environmental sensor module  110  to determine that the UE  101  is in a metal structure that acts similarly to a Faraday&#39;s cage. The communication controller  130  controls the wireless communication module  120  to enter a power saving mode to save energy until the UE  101  exits the metal structure. 
     In another embodiment, the communication controller  130  receives inputs from the surrounding temperature sensor. Based on the surrounding temperature, the communication controller  130  controls the wireless communication module  120  to adjust the transmission power. For example, when the surrounding temperature is higher than a threshold, the communication controller  130  controls the wireless communication module  120  to increase the transmission power. 
     The communication controller  130  can be implemented by various techniques. In an example, the communication controller  130  is implemented as logic circuits. In another example, the communication controller  130  is implemented as instruction codes stored in a computer readable medium. The instruction codes are executed by a processor to perform the control operations. 
       FIGS. 2A and 2B  show simplified block diagrams of a mobile phone  201  ( 201 A in  FIG. 2A and 201B  in  FIG. 2B ) during operation according to an embodiment of the disclosure. The mobile phone  201  includes a G-sensor  210  ( 210 A in  FIG. 2A and 210B  in  FIG. 2B ), a wireless communication module  220  ( 220 A in  FIG. 2A and 220B  in  FIG. 2B ), and a communication controller  230  ( 230 A in  FIG. 2A and 230B  in  FIG. 2B ). In an embodiment, the communication controller  230  includes a memory  231  ( 231 A in  FIG. 2A and 231B  in  FIG. 2B ). 
     In the embodiment, the mobile phone  201  is configured to perform telecommunication via a servicing base station. In an example, initially, the wireless communication module  220  performs a scan process to search for a base station as its servicing base station to receive service. Further, periodically, the wireless communication module  220  listens to signals from the servicing base station, measures signal quality, and determines whether it is necessary to switch to another base station. For example, when the wireless communication module  220  has strong reception, for example, signal strength being larger than a threshold, the wireless communication module  220  stay camped on to the servicing base station. However, when the wireless communication module  220  has a weak reception, for example, signal strength being smaller than a threshold, the wireless communication module  220  starts a scan process, such as a partial scan process, a full scan process, and the like, to search for another servicing base station with which a better communication link is available. 
     The communication controller  230  receives inputs from the G-sensor  210 . Based on the inputs from the G-sensor  210 , the communication controller  230  determines whether the mobile phone  201  is in an elevator, for example, and controls the operations of the wireless communication module  220 , such as a scan process, based on the determination. 
     In  FIG. 2A , during operation, when the wireless communication module  220 A has a weak reception, the wireless communication module  220 A informs the communication controller  230 A of the weak reception. 
     In response to the weak reception, the communication controller  230 A stores the present servicing base station as a last servicing base station in the memory  231 A. In addition, in an example, the communication controller  230 A sends a signal to activate the G-sensor  210 A, and starts to receive inputs from the G-sensor  210 A. In an embodiment, the communication controller  230 A sends a signal to the wireless communication module  220 A to start a scan process to search for another servicing base station. In another embodiment, the wireless communication module  220 A automatically starts a scan process to search for another servicing base station. 
     In  FIG. 2B , the G-sensor  210 B senses gravitational field and provides gravitational information, such as sensed gravitation values, to the communication controller  230 B. Based on the sensed gravitation values, the communication controller  230 B detects vertical dynamics and determines whether the mobile phone  201 B is in an elevator based on the vertical dynamics. Based on the determination, the communication controller  230 B sends control signals to the wireless communication module  220 B. 
     In an embodiment, the communication controller  230 B receives sensed gravitation values from the G-sensor  210 B. The communication controller  230 B compensates the sensed gravitation value to determine a vertical acceleration. Further, in an example, the communication controller  230 B integrates the vertical acceleration over time. The integration of vertical acceleration is indicative of a vertical velocity of the mobile phone  201 B. In an example, when the absolute value of the integration is larger than the threshold, the communication controller  230  determines that the mobile phone  201 B has vertical movement. 
     Further, in an example, the communication controller  230 B integrates the vertical velocity of the mobile phone  201 B. The integration of the vertical velocity is indicative of a vertical distance traveled by the mobile phone  201 B. In an example, when the absolute value of the integration is larger than a floor height, the communication controller  230  determines that the mobile phone  201 B is in an elevator. 
     According to an aspect of the disclosure, the communication controller  230 B keeps track of the vertical acceleration of the mobile phone  201 B. In an example, when the vertical acceleration changes sign, for example, from positive to negative, the communication controller  230 B determines that the elevator is about to stop. In another example, when the vertical velocity is zero, the communication controller  230 B determines that the elevator stops. In another example, when the vertical velocity stays zero for a time duration that is greater than a threshold, the communication controller  230 B determines that the elevator stops. It is noted that, in an example, the threshold is configurable. In the case of an elevator, the threshold accommodates, e.g., intermediate stops. 
     In an embodiment, when the elevator stops, the communication controller  230 B sends a signal to the wireless communication module  220 B to start a scan process from the last servicing base station to search for a servicing base station. 
     In another embodiment, when the communication controller  230 B determines that the mobile phone  201 B is in an elevator, for example, by sensing vertical acceleration/deceleration, or by detecting presence in a Faraday&#39;s cage, the communication controller  230 B instructs the wireless communication module  220 B to monitor received signal strength periodically, such as every 1 ms. When the wireless communication module  220 B starts to have strong reception, the communication controller  230 B determines that the elevator stops, and instructs the mobile phone  201 B to start a scan process from the last servicing base station to start search for a servicing base station. 
     According to an aspect of the disclosure, an elevator may act as a Faraday&#39;s cage to block communication signals in the air. Thus, when a mobile phone enters the elevator, the mobile phone loses reception; and when the mobile phone exits the elevator, the mobile phone regains reception. Then, presence in an elevator can be determined by detecting a Faraday&#39;s cage, and/or sensing vertical acceleration. 
     In the  FIG. 2A  and  FIG. 2B  example, when the mobile phone  201  enters the elevator, the mobile phone  201  loses reception, and saves the last servicing base station. When the mobile phone  201  exits the elevator, the mobile phone  201  starts a scan process from the last servicing base station, and quickly re-locks to the last servicing base station to receive wireless communication service from the relocked servicing base station. 
     In a comparison example, when a comparison mobile phone enters the elevator, the comparison mobile phone loses reception from a present servicing base station, and starts a scan process to search for another servicing base station. Due to the weak reception, the comparison mobile phone may fail a partial scan, and starts a full scan process. When the comparison mobile phone exits the elevator, the comparison mobile phone is in a middle of the partial scan or the full scan. Then, it may take tens of seconds to couple of minutes for the comparison mobile phone to finish the scan process, and re-lock to the last servicing base station. According to another aspect, the searching operations in the elevator waste power, because presence in a Faraday&#39;s cage typically precludes receipt of suitable signals. 
     It is noted that the mobile phone  201  can use inputs from other sensors to detect whether the mobile phone  201  enters or exits an elevator. In an example, the mobile phone  201  uses inputs from an internal radar configured to detect a metal structure that acts as a Faraday&#39;s cage to determine whether the mobile phone  201  enters or exits an elevator. 
       FIG. 3  shows a flow chart outlining a process example  300  for governing communication operations based on a sensed environmental condition according to an embodiment of the disclosure. In an embodiment, the process  300  is executed by the mobile phone  201  in  FIG. 2A  and  FIG. 2B . The process starts at S 301  and proceeds to S 310 . 
     At S 310 , the mobile phone  201  receives weak reception. In an example, initially, the mobile phone  201  is camped to a servicing base station for wireless communication service. Periodically, the wireless communication module  220  listens to the servicing base station, and evaluates signal quality received from the servicing base station. When the signal quality is high, for example, the signal strength being larger than a threshold, the wireless communication module  220  remain camped to the servicing base station. However, when the signal quality is lower, for example, the signal strength being lower than a threshold, the wireless communication module  220  has a weak reception to the present servicing base station or even loses reception from the present servicing base station. When the wireless communication module  220  detects the weak reception, the wireless communication module  220  sends a signal to the communication controller  230  to inform the weak reception. In an embodiment, in response to the weak reception, the communication controller  230  stores the present servicing base station as a last servicing base station in the memory  231 . 
     At S 320 , the communication controller  230  controls the wireless communication module  220  to start a scan process to search for a suitable servicing base station. In an embodiment, the communication controller  230  controls the wireless communication module  220  to start a partial scan process to search for suitable servicing base station according to a list of a subset of base stations. In another embodiment, the communication controller  230  controls the wireless communication module  220  to start a full scan process to search for suitable servicing base station. It is noted that, in an embodiment, the wireless communication module  220  starts the scan process by itself when weak reception is detected. 
     At S 330 , the communication controller  230  activates sensors, such as the G-sensor  210 , for example. The communication controller  230  starts to receive inputs from the G-sensor  210  and detects vertical dynamics of the mobile phone  201  based on the inputs. In an embodiment, the communication controller  230  sets up a timer for the sensors. 
     At S 340 , the communication controller  230  determines whether there is vertical movement. In an example, the communication controller  230  receives a gravitation value from the G-sensor  210 . The communication controller  230  compensates for the gravitation value to detect vertical acceleration. Then, the communication controller  230  integrates the vertical acceleration over time to detect vertical velocity. When an absolute value of the vertical velocity is larger than a threshold, the communication controller  230  determines that the mobile phone  201  has vertical movement, and the process proceeds to S 350 ; otherwise, the communication controller  230  determines that the mobile phone  201  does not have vertical movement, and the process proceeds to S 399  and terminates. 
     At S 350 , the communication controller  230  tracks the vertical movement until a stop is detected. In an embodiment, the communication controller  230  keeps track of the vertical acceleration. When the vertical acceleration changes sign, such as from positive to negative, or from negative to positive, the communication controller  230  detects that the vertical movement is about to stop. In another embodiment, the communication controller  230  keeps track of the vertical velocity. When the vertical velocity is zero, the communication controller  230  detects that the vertical movement stops. 
     At S 360 , the communication controller  230  determines whether the vertical movement causes the mobile phone  201  to travel a vertical distance that is larger than a threshold, such as a floor height, and the like. When the vertical distance is larger than the floor height, the process proceeds to S 370 ; otherwise, the process proceeds to S 380 . 
     At S 370 , the communication controller  230  sends a signal to the wireless communication module  220  to restart a scan process from the stored last servicing base station. The process proceeds to S 399  and terminates. 
     At S 380 , the communication controller  230  determines whether a sensor time-out happens. When the sensor time-out happens, the process proceeds to S 399  and terminates; otherwise, the process returns to S 340  to detect vertical movement. 
     It is noted that the process  300  can be suitably modified. In an example, at S 370 , after the wireless communication module  220  restarts a scan process from the stored last serving base station, the process returns to S 340  to detect further vertical movement. In another example, S 320  and S 330  are executed in parallel or in a different order. 
     While the invention has been described in conjunction with the specific embodiments thereof that are proposed as examples, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, embodiments of the invention as set forth herein are intended to be illustrative, not limiting. There are changes that may be made without departing from the scope of the invention.