Abstract:
A wireless mobile device capable of developing a wireless fidelity (Wi-Fi) access point map. The mobile device comprises a Wi-Fi module and a processor. The Wi-Fi module is configured to communicate with a plurality of Wi-Fi access points and determine a signal strength from at least one of the Wi-Fi access points at each of a plurality of locations. The processor is configured to display a Wi-Fi access point map on a display of the mobile device, the map configured to associate the signal strength of the at least one Wi-Fi access point with each location, and direct a user of the mobile device to a location on the map, the location on the map having a stronger Wi-Fi signal that a current location of the mobile device.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present application relates generally to wireless communication and, more specifically, to a system and method for developing a Wi-Fi access point map using sensors in one or more wireless mobile devices. 
       BACKGROUND OF THE INVENTION 
       [0002]    Today, many buildings and campuses include a number of wireless fidelity (Wi-Fi) access points. Such Wi-Fi access points allow wireless devices (especially mobile devices) access to one or more Wi-Fi networks. Through a Wi-Fi network, each wireless device may browse the Internet, exchange emails, hold voice conversations, or engage in a variety of other types of communication. 
         [0003]    In many cases, a building may not have enough Wi-Fi access points to provide an acceptable wireless signal throughout the building. For example, wireless devices in some floors or wings of the building may experience a good Wi-Fi signal, while wireless devices in other floors or wings of the building may experience a poor Wi-Fi signal. Materials in walls, ceilings, and floors further affect a Wi-Fi signal. 
         [0004]    When a user of a wireless device is in a location that does not have a good Wi-Fi signal, he or she may wish to move to a location associated with a stronger signal. However, the user may not be very familiar with the building, or with the Wi-Fi signal coverage throughout the building, in order to know where to move. Furthermore, even though the Wi-Fi module of prior art wireless devices can remember the SSID and credentials for a particular Wi-Fi access point, it typically cannot remember the overall Wi-Fi coverage of a building with multiple Wi-Fi points. Thus, the user cannot rely on a prior art wireless device to receive directions to move to a better coverage area. 
       SUMMARY OF THE INVENTION 
       [0005]    A wireless mobile device capable of developing a wireless fidelity (Wi-Fi) access point map is provided. The mobile device comprises a Wi-Fi module and a processor. The Wi-Fi module is configured to communicate with a plurality of Wi-Fi access points and determine a signal strength from at least one of the Wi-Fi access points at each of a plurality of locations. The processor is configured to display a Wi-Fi access point map on a display of the mobile device, the map configured to associate the signal strength of the at least one Wi-Fi access point with each location, and direct a user of the mobile device to a location on the map, the location on the map having a stronger Wi-Fi signal that a current location of the mobile device. 
         [0006]    A method of using a Wi-Fi access point map is provided. The method comprises communicating with a plurality of Wi-Fi access points. The method also comprises determining a signal strength from at least one of the Wi-Fi access points at each of a plurality of locations. The method further comprises displaying a Wi-Fi access point map on a display of a wireless device, the map configured to associate the signal strength of the at least one WiFi access point with each location. The method still further comprises directing a user of the device to a location on the map, the location on the map having a stronger Wi-Fi signal that a current location of the device. 
         [0007]    A wireless communication network is provided. The network comprises a plurality of Wi-Fi access points and an administrator configured for communication with the Wi-Fi access points and with a plurality of wireless mobile devices. The administrator is configured to receive from each of the mobile devices data comprising a plurality of locations and a signal strength of at least one of the Wi-Fi access points at each of the locations. The administrator is also configured to develop a Wi-Fi access point map, the map configured to associate the signal strength of the Wi-Fi access points with each location. The administrator is further configured to provide the Wi-Fi access point map to at least one of the mobile devices. 
         [0008]    Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
           [0010]      FIG. 1  illustrates a wireless mobile device according to one embodiment of the present disclosure; 
           [0011]      FIG. 2  illustrates a Wi-Fi network configured for developing a Wi-Fi access point map, according to one embodiment of the present disclosure; and 
           [0012]      FIG. 3  depicts another aspect of operation of the Wi-Fi network, according to one embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0013]      FIGS. 1 through 3 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged wireless network. 
         [0014]    The present disclosure provides a system and method for developing a map of Wi-Fi access points in a location such as a building, using one or more wireless devices with a 3D magnetic compass, accelerometer sensor, and Wi-Fi module. The word “building” as used herein means any building, group of buildings, spaces around a building, campus, or similar area where Wi-Fi access points would be located. 
         [0015]      FIG. 1  illustrates a wireless mobile device according to one embodiment of the present disclosure. Wireless mobile device  100  comprises antenna  105 , radio frequency (RF) transceiver  110 , transmit (TX) processing circuitry  115 , microphone  120 , and receive (RX) processing circuitry  125 . Wireless mobile device  100  also comprises speaker  130 , main processor  140 , input/output (I/O) interface (IF)  145 , keypad  150 , display  155 , and memory  160 . Wireless mobile device  100  further comprises an accelerometer sensor  170 , compass  175 , and, optionally, a global positioning system (GPS) receiver  180 . 
         [0016]    Radio frequency (RF) transceiver  110  receives from antenna  105  an incoming RF signal transmitted by a base station of a wireless network, such as network  130 . Radio frequency (RF) transceiver  110  down-converts the incoming RF signal to produce an intermediate frequency (IF) or a baseband signal. The IF or baseband signal is sent to receiver (RX) processing circuitry  125 , which produces a processed baseband signal by filtering, digitizing the baseband or IF signal, additional filtering, if necessary, demodulation and/or decoding. Receiver (RX) processing circuitry  125  transmits the processed baseband signal to speaker  130  (i.e., voice data) or to main processor  140  for further processing (e.g., web browsing). 
         [0017]    Transmitter (TX) processing circuitry  115  receives analog or digital voice data from microphone  120  or other outgoing baseband data (e.g., web data, e-mail, interactive video game data) from main processor  140 . Transmitter (TX) processing circuitry  115  encodes, modulates, multiplexes, and/or digitizes the outgoing baseband data to produce a processed baseband or IF signal. Radio frequency (RF) transceiver  110  receives the outgoing processed baseband or IF signal from transmitter (TX) processing circuitry  115 . Radio frequency (RF) transceiver  110  up-converts the baseband or IF signal to a radio frequency (RF) signal that is transmitted via antenna  105 . In accordance with embodiments of the present disclosure, RF transceiver  110 , processing circuitry  115  and  125 , and/or main processor  140  comprise a Wi-Fi module configured for Wi-Fi communication. 
         [0018]    In certain embodiments, main processor  140  is a microprocessor or microcontroller. Memory  160  is coupled to main processor  140 . In certain embodiments, part of memory  160  comprises a random access memory (RAM) and another part of memory  160  comprises a non-volatile memory, such as Flash memory, which acts as a read-only memory (ROM). 
         [0019]    Main processor  140  controls the overall operation of wireless device  100 . In one such operation, main processor  140  controls the reception of forward channel signals and the transmission of reverse channel signals by radio frequency (RF) transceiver  110 , receiver (RX) processing circuitry  125 , and transmitter (TX) processing circuitry  115 , in accordance with well-known principles. Main processor  140  executes software stored in memory  160  in order to control the overall operation of wireless device  100 . 
         [0020]    Main processor  140  is capable of executing other processes and programs resident in memory  160 . Main processor  140  can move data into or out of memory  160 , as required by an executing process. Main processor  140  is also coupled to I/O interface  145 . I/O interface  145  provides mobile device  100  with the ability to connect to other devices such as laptop computers and handheld computers. I/O interface  145  is the communication path between these accessories and main controller  140 . 
         [0021]    Main processor  140  is also coupled to keypad  150  and display unit  155 . The operator of mobile device  100  uses keypad  150  to enter data into mobile device  100 . Display  155  may be a liquid crystal display capable of rendering text and/or graphics from web sites. In certain embodiments, display  155  may be a touch-sensitive screen and keypad  150  may be displayed on the touch-sensitive screen of display  155 . Alternate embodiments may use other types of displays. 
         [0022]    In accordance with embodiments of the present disclosure, main processor  140  is coupled to accelerometer sensor  170  and compass  175 . Compass  175  may be, for example, a 3D magnetic compass. In certain embodiments, wireless device  100  also includes GPS receiver  180 , which is coupled to main processor  140 . Accelerometer  170 , compass  175 , and optional GPS receiver  180  enable wireless device  100  to track and provide location and orientation information, as described in greater detail herein. 
         [0023]      FIG. 2  illustrates a Wi-Fi network configured for developing a Wi-Fi access point map, according to one embodiment of the present disclosure. Wi-Fi network  200  comprises a number of Wi-Fi access points, represented by access points  201 ,  202 , and  203 . Wi-Fi network  200  also comprises user  210 , mobile device  212 , and administrator  215 . Wi-Fi network  200  may be located substantially inside a building  220 . Building  220  may include one or more stories, one or more interior rooms or areas, and one or more hallways or passageways. 
         [0024]    Mobile device  212  may represent wireless mobile device  100  in  FIG. 1 . Mobile device  212  is in wireless communication with one or more access points  201 - 203 . Access points  201 - 203  are in wireless and/or wired communication with each other and with administrator  215 . User  210  uses wireless device  212  to engage in wireless communication via Wi-Fi network  200 . In certain embodiments, administrator  215  may serve as network controller or network administrator for Wi-Fi network  200 . In other embodiments, controller and administrator functions for Wi-Fi network  200  may be performed by one or more other devices (not shown). Likewise, administrator  215  may be an IT, network, or data administrator for a company, building  220 , etc. Administrator  215  may be located inside building  220 , or may be remote to building  220 . 
         [0025]    Mobile device  212  includes one or more algorithms for determining the location, orientation, and direction and speed of movement of device  212 . The algorithms use empirical data which may be determined from reference experiments and preloaded into mobile device  212 , or may be acquired over time during use of mobile device  212 . In certain embodiments, the algorithms may be stored in memory  160  of mobile device  212 . The algorithms may be used to carry out the operations of mobile device  212  described in greater detail below. 
         [0026]    In one aspect of operation, mobile device  212  uses compass  175  and accelerometer sensor  170  to determine the location and orientation of device  212  within building  220 . Using readings from accelerometer  170 , along with a low pass filter associated with the accelerometer  170 , mobile device  212  calculates the direction of gravity. Mobile device  212  uses digital compass  175  in conjunction with accelerometer  170  to detect the direction that device  212  is facing. As mobile device  212  moves, it uses compass  175  and accelerometer sensor  170  to detect changes in location, orientation, and direction of movement, as well as speed of movement. In certain embodiments, the location, orientation, and direction and speed of movement are determined with respect to a known point or landmark, e.g., an entrance to building  220 . Thus, mobile device  212  is aware of its movement around building  220 . For example, mobile device may sense that it is moving up a stair well, down a hallway, or in any other direction. 
         [0027]    As described earlier, mobile device  212  may optionally include GPS receiver  180 . A GPS receiver typically does not operate well within a building. Thus, GPS receiver  180  may not be used to track wireless device  212  while it is in building  220 . However, some buildings, particularly large ones, may have multiple entrances from the outside. In such a case, GPS receiver  180  may be used to determine which entrance device  212  uses to enter building  220 . Then once inside building  220 , device  212 &#39;s location can be determined from its movement away from that entrance. 
         [0028]    As mobile device  212  moves within building  220 , the Wi-Fi RSSI (signal strength) associated with nearby Wi-Fi access points changes. Since each Wi-Fi access point has a unique BSSID or MAC address to identify itself, mobile device  212  can detect the handoff between access points and estimate an approximate distance and direction to each nearby access point. The Wi-Fi environmental data is cached on device  212 . Later, device  212  may use the Wi-Fi environmental data to prompt user  210  to move to a different location if the Wi-Fi coverage is poor at a particular location. 
         [0029]    In certain embodiments, mobile device  212  includes a simple Wi-Fi locator user interface. The simple user interface may provide an arrow or similar indicator on display  155  that points in a direction where better Wi-Fi coverage is located. In other embodiments, mobile device  212  includes a more detailed Wi-Fi locator user interface. The more detailed user interface may display an actual map or simulation of building  220  with indicators pinpointing the location of better coverage. The user interface may include verbal or textual directions guiding a user to an improved Wi-Fi signal. For example, empirical data obtained from the accelerometer and compass could be used to provide very detailed step-by-step directions for navigating the building, such as “move 10 meters east” or “walk  10  steps down the hallway and turn right, then take 3 more steps” or “take the elevator to the third floor and go 20 feet west from the elevator.” 
         [0030]      FIG. 3  depicts another aspect of operation of the Wi-Fi network, according to one embodiment of the present disclosure. In this embodiment, administrator  215  is used to obtain information related to Wi-Fi coverage, and provide the information to mobile device  212 . In one embodiment, administrative personnel may walk (or otherwise move) one or more smart wireless devices (e.g., device  212 ) around building  220  to survey Wi-Fi signal strength readings throughout building  220 . This information is then sent to administrator  215  for processing and storage. Alternatively or additionally, Wi-Fi coverage information is collected from a variety of devices (e.g., devices  212 ,  222 ,  232 ,  242 ) over time, with each device reporting coverage information to administrator  215  as it is moves to a new location or encounters a change in Wi-Fi signal strength. This method is particularly useful in a building with many wireless devices that move around the building. 
         [0031]    For example, assume building  220  is populated with a number of wireless devices (e.g., devices  222 ,  232 ,  242 ) similar to device  212 . As each wireless device moves about building  220 , the device provides an indication of Wi-Fi signal strength to administrator  215 , which collects the aggregate data. For example, as device  212  provides signal strength information to administrator  215 , administrator  215  identifies the location of device  212  using RSSI readings. Alternatively, device  212  may provide its location information based on data from accelerometer  170  and compass  175 . As Wi-Fi signal strength data is collected over time from multiple devices in multiple locations, each location is associated with a particular signal strength. If multiple devices report a signal strength for a single location, administrator  215  may calculate a representative strength for the location, such as by averaging the various reported values. Thus, administrator  215  will develop a map of signal strengths over time. Later, administrator  215  may push the map down to device  212 . In certain embodiments, the map is customized based on the location of device  212 . 
         [0032]    Signal strength information may be constantly received and processed by administrator  215 . The information is then shared with wireless device  212  according to a variety of time tables. In certain embodiments, signal strength information is requested by device  212  continuously, periodically according to a predetermined time schedule, or only when prompted by user  210 . In other embodiments, signal strength information is pushed from administrator  215  to device  212  automatically, either continuously or periodically according to a predetermined time schedule. 
         [0033]    As described earlier, wireless device  212  may develop its own map of signal strengths as it moves about building  220 . In this case, device  212  would not need to get Wi-Fi signal information from administrator  215 . However, building map information from administrator  215  could be sent to device  212  to augment the Wi-Fi signal map information generated by device  212 . 
         [0034]    Embodiments of the present disclosure may have additional applications. For example, the disclosed system may be used by IT administrators to survey Wi-Fi environmental parameters in a location (e.g., a building) and optimize the placement of the access points around the location. The disclosed system may also be used to trace a phone within an enterprise&#39;s premise. 
         [0035]    Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.