Abstract:
A mobile receiver is programmed with available channels by initially searching for all potentially available channels and autoprogramming the receiver with channels that are detected by the receiver. Subsequently, only potentially available channels that have not been programmed into the receiver are searched for to reduce autoprogramming time when, e.g., the mobile receiver is carried to a higher elevation.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to automatically programming channels into mobile receivers such as mobile televisions and radios. 
     BACKGROUND OF THE INVENTION 
     When a television is initially installed in a user&#39;s home after purchase, the receiver of the TV automatically searches for channels that are available in the area and records information pertaining to available channels in memory using a data structure known as a “channel map”. The channel map includes information for each available channel, such as channel frequency. Without a channel map the receiver otherwise would tune to the next higher channel in response to a “channel up” command regardless of whether a signal is present. This also would be the case for channel changes for decrementing the channel number. The search and record function is known as “autoprogramming” because it automatically programs the TV with information pertaining to available channels. 
     As understood herein, with the advent of digital televisions and hundreds of satellite channels, digital ones of which might in fact carry several sub-channels, the autoprogramming function discussed above can consume much time. This is not only because of the increased number of channels but also because digital channels are more complicated to map, requiring not just a frequency map but also various decoding information. 
     As also understood herein, the location of a mobile TV receiver frequently can change and with it the available channels, precipitating another autoprogramming cycle even if the location of the receiver and thus the identity of available channels haven&#39;t changed much. Indeed, as recognized herein due to variable reception conditions such as elevation, shielding by buildings or terrestrial objects, etc, a mobile receiver may not be able to detect all the potentially available channels in a given location at a given time, although such channels might become immediately available when the receiver is moved a relatively short distance. 
     SUMMARY OF THE INVENTION 
     To avoid a complete cycle of autoprogramming a receiver when the receiver has been moved a comparatively short distance that permits the receiver to receive signals from many if not most of the channels that are already programmed into the receiver, the receiver searches only for channels that have not yet been programmed into it. 
     Accordingly, a method for programming a mobile receiver with available channels includes initially searching for all potentially available channels, and programming the receiver with channels that are detected by the receiver. The method also includes subsequently searching only for potentially available channels that have not already been programmed into the receiver. 
     In some implementations the partial search is executed automatically in response to a determination that the receiver has moved, e.g., in altitude and/or beyond a threshold. The potentially available channels may be indicated by a potentially available channel map, and channels that are detected during initial full autoprogramming can be listed on an actually available channel map. Then, channels detected during subsequent partial scans may be added to the actually available channel map. The actually available channel map can then be invoked in response to, e.g., a channel command. If desired, peer to peer information may be used to generate the actually available channel map. 
     In another aspect, a mobile receiver has a channel tuner, a processor communicating with the tuner, and a computer readable medium accessible to the processor. The medium can include instructions to cause the processor to control the tuner to execute a scan of all frequencies in a group of frequencies associated with potentially available channels. Information related to all channels detected during the scan is added to an actually available channel data structure. Subsequently, a scan is executed only of frequencies in the group of frequencies that are not associated with channels in the actually available channel data structure. 
     In another aspect, a system includes means for tuning to each of plural potentially available channels, and means for adding potentially available channels that are detected to an actually available channel listing. Means are provided for, subsequent to adding the potentially available channels that are detected to the actually available channel listing, scanning only potentially available channels not already on the actually available channel listing. 
     The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective of an example implementation of the receiver, with some components shown schematically; 
         FIG. 2  is a flow chart of example logic that may be used in accordance with present principles; and 
         FIG. 3  is an example graphical user interface (GUI) that can be used to allow a user to initiate quick autoprogramming. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring initially to  FIG. 1 , a mobile receiver  10  includes a portable, typically hand-held lightweight hollow housing  12  bearing a video display  14  such as but not limited to a flat panel matrix display, a microdisplay device, a laser or LED-based microprojection device, etc. The display  14  may be standard definition video, high definition video, or other type of video display. Thus, while the receiver  10  in  FIG. 1  is a TV receiver it is to be understood that the receiver alternatively may be, e.g., an AM/FM radio receiver, etc. that is configured to receive plural channels of typically broadcast programming. 
     Being a mobile receiver  10 , the housing  12  may also bear one or more DC batteries  16 . In some embodiments the housing  12  can further include an AC power receptacle to receive AC power from the electrical grid. 
     As shown in  FIG. 1 , the receiver  10  includes a processor  18  that controls the display  14  in response to user commands such as channel up/down commands, volume up/down commands, etc. input by means of control keys  20  on the housing  12  and/or by means of keys  22  on a wireless remote control  24  communicating with the processor  18 . The example receiver  10  of  FIG. 1  also includes a TV tuner  26  communicating with the processor  18  for outputting signals from a channel on a tuned-to frequency for presentation on the display  14 . 
     The processor  18  also accesses a computer readable medium  28  such as disk-based storage, solid state storage, etc. Computer instructions embodying the logic of  FIG. 2  may be contained on the medium  28 , as can data structures such as one or more channel maps or other appropriate data structures (e.g., tables) each of which can be correlated to respective geographic locations if desired. 
     In example embodiments the processor  18  can also receive position information from a position receiver  30  such as but not limited to a geographic position satellite (GPS) receiver. In addition or alternatively as user can input a geographic location using the control keys  20 ,  22 . An antenna  32  may also be provided on the housing for receiving broadcast signals, which may be sent to the processor  18 . 
     Now referring to  FIG. 2 , an initial autoprogramming is executed at block  34  in which all potentially available frequencies are scanned for to detect available channels. The initial autoprogramming may be accomplished automatically upon first energization in a geographic region as indicated by, e.g., the signal from the position receiver  30  or by user input, and/or it may be done in response to a user command using, e.g., the GUI of  FIG. 3  discussed further below. 
     In some embodiments, to execute block  34  the processor  18  accesses a pre-stored potentially available channel map in the medium  28 , in some implementations using geographic location as entering argument. The channel map defines all of the channels that are potentially available, and all channels on the potentially available channel map are scanned at block  34 . 
     In other implementations, upon initial power on the receiver  10  can receive a transmitter location data base which provides the potentially available channel map listing all potentially available channels for which to scan. 
     In still other embodiments no initial channel map may be provided, in which case the processor  18  simply scans each frequency on which a channel might be carried in the relevant band (e.g., the TV channel frequency band) from, e.g., lowest frequency to highest. In this case, each frequency on which a channel might be carried in the relevant band in effect defines the potentially available channel map. Scanning the band enables the processor  18  to determine if a channel signal is found at each frequency. 
     Based on the channels that are detected as being actually available during the scan, the processor  18  constructs an “actually available channel” map. At block  36  the channels on the actually available channel map are autoprogrammed into the receiver  10 . Autoprogramming may include, e.g., programming information for each channel found to be available at block  34  including, e.g., channel frequency, decoding information for digital channels, etc. 
     In the event that the receiver  10  is moved, the logic of block  38  can be executed. At block  38 , only frequencies associated with channels that were not detected as being available at block  34  are scanned to determine if channel signals can detected on those frequencies such that autoprogramming time subsequent to initial autoprogramming advantageously can be minimized. In one example implementation the processor  34  accesses the “actually available channel” map and compares it to the potentially available channel map and scans only for channels of the potentially available channel map that are not also listed on the actually available channel map. 
     For example, if the receiver  10  is moved from a relatively low height to a relatively high height, e.g., to a high floor in a building, additional channels may be detected that were undetected at block  34  during initial autoprogramming at the lower height. Under these circumstances the newly available channels are quickly autoprogrammed because only frequencies that were not detected to carry channel signals at block  34  are scanned. 
     To this end, in some example embodiments signals from the position receiver  30  can be used to provide elevation information. Or, the user may manually enter elevation information. In either case, the logic at block  38  may be automatically executed upon receipt of elevation data that differs from prior (or default) elevation information by more than a threshold amount. 
     Yet again, as shown in  FIG. 3  a GUI can be presented on the display  14  in response to selection of “autoprogram” from a higher level menu. The GUI may include a “full autoprogram” selection, which if selected by the user by means of, e.g., the control keys  20 / 22  causes the logic of block  34  to be executed. The GUI may also include a “quick autoprogram update” selection which, if selected, causes the logic of Block  38  to be executed. 
     Still further, the logic of block  38  may be executed automatically when signals from, e.g., the position receiver  30  indicate a change in location greater than a local area threshold, indicating that the receiver substantially remains in the area in which the initial autoprogram was executed but has moved sufficiently to open the possibility that previously unavailable channels might have become available. Along these same lines the full autoprogram logic of block  34  may be executed automatically when signals from, e.g., the position receiver  30  indicate a change in location greater than a wide threshold, indicating that the receiver  10  has moved substantially completely out of the area in which the initial autoprogram was executed. 
     In any case, in non-limiting embodiments based upon a TV transmitter&#39;s height above average terrain (HAAT) data that can be stored in, e.g., the medium  28 , the receiver  10  can access a transmitter database in, e.g. the medium  28  to identify neighboring areas for additional potential channels for which to scan, in addition to or in lieu of the channel map comparison described above. Additionally or alternatively, a reception prediction algorithm such as the Longley-Rice algorithm can be executed by the processor  18  to determine which channels are potentially available given the height of the receiver  10 . 
     In addition to or in lieu of using GPS as a position receiver, multiple means may be used for determining the location of the receiver. For example, reception of stations of known geographic location can be used as a determination of the location of the receiver  10 . Yet again, a last known location of the receiver  10  may be used to predict the current location of the receiver  10 , e.g., based on historical scan patterns the processor  18  may always execute the partial scan of block  38  at a certain location, anticipating movement to another location. Or, the processor can use time of day to make assumptions based upon prior usage in order to predict the location. Alternatively, an absolute or relative pressure sensor such as a Silicon-based sensor may be used in the receiver  10  for detecting elevation changes. Still further, the receiver  10  may incorporate an equalizer/ghost canceller filter and if it does, the processor  18  may monitor for changes in the associated filter coefficients greater than a threshold, and/or equalizer tap energy, indicating that a location change or other change potentially making additional channels available has occurred and thus triggering the partial scan logic. 
     If desired, a group of users using similar receivers  10  can use peer to peer communication to alert each other of the content of a local actually available channel map. In such an embodiment each receiver  10  would include a transmitter such as a WiFi transmitter or wireless telephony transmitter. 
     As contemplated herein, in the event that the receiver  10  is moved from an area of good reception to an area of poor reception, the entire autoprogram logic of block  34  may be re-executed, or, if an “actually available channel” map exists for the area of poor reception, that map can be retained in memory and then invoked for channel surfing purposes in lieu of the “actually available channel.” map for the area of good reception when the position receiver  30  indicates that the mobile receiver  10  is back in the area of poor reception. 
     While the particular EFFICIENT MOBILE RECEIVER AUTOPROGRAMMING is herein shown and described in detail, it is to be understood that the subject matter which is encompassed by the present invention is limited only by the claims.