Abstract:
The disclosure provides a satellite finding apparatus and satellite finding method, includes a set-top-box (STB) and a satellite antenna receiving device (SARD). The STB receives signals from the satellite antenna receiving device, and the STB comprises a central processing unit, a power transforming unit, a satellite switching judging module, a driving controlling module and a current detecting module. The SARD includes motors, tuners and antennas. The disclosure further provides a satellite finding method. The satellite finding apparatus will perform short-circuit detection if a switch of satellite is determined upon. The disclosure enables the motor only at the time when the satellite finding apparatus needs to find the satellite, it can save energy and prevents the destroying of the motor.

Description:
FIELD 
       [0001]    The present disclosure generally relates to satellite finding technology of digital televisions, and more particularly to a satellite finding apparatus and satellite finding method. 
       BACKGROUND 
       [0002]    In digital satellite receiving system, a control signal from a signal line between a set-top-box (STB) and a satellite receiver is transmitted to a Low Noise Block (LNB), a polar axis seat, and other devices to switch satellites. Satellite antenna and LNB device are active devices and they work outside, so they are easily effected by the environment. The STB transmits the control signal to a motor to rotate the polar axis seat for receiving satellite signals. The motor only works at the time while repositioning to focus on a satellite, so most of the time the motor is idle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    Implementations of the present technology will now be described, by way of example only, with reference to the attached figures, wherein: 
           [0004]      FIG. 1  is a configuration schematic diagram of a satellite finding apparatus according to one embodiment of the disclosure. 
           [0005]      FIG. 2  is a configuration schematic diagram of a STB according to an embodiment of the disclosure. 
           [0006]      FIG. 3  is a configuration schematic diagram of a satellite antenna receiving device according to an embodiment of the disclosure. 
           [0007]      FIG. 4  is a process diagram of a satellite finding method according to an embodiment of the disclosure. 
           [0008]      FIG. 5  is a process diagram of the short circuit detection according to an embodiment of the disclosure. 
           [0009]      FIG. 6  is a diagram of coding scheme of switch controlling command according to an embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure. The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean “at least one”. 
         [0011]    Several definitions that apply throughout this disclosure will now be presented. 
         [0012]    The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The connection can be such that the objects are permanently connected or releasably connected. The term “comprising,” when utilized, means “including, but not necessarily limited to”. it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like. 
         [0013]      FIG. 1  shows a configuration schematic diagram of a satellite finding apparatus DO according to one embodiment of the disclosure. 
         [0014]    In one embodiment, satellite finding apparatus DO comprises a set top box (STB)  10  and a satellite antenna receiving device  20 . The STB  10  is electrically connected to satellite antenna receiving device  20  via signal line  120 . STB  10  receives an antenna signal from satellite antenna receiving device  20 , and signal line  120  can be a coaxial cable. As shown in  FIG. 1 , remote control  30  and keyboard  31  are coupled to STB  10 , and are configured to input channel switch commands and any other control inputs. The connection types of STB, remote control  30 , and keyboard  31  can be wired or wirelessly connected. In other embodiment, keyboard  31  can be included in STB  10 . 
         [0015]      FIG. 2  is a configuration schematic diagram of STB  10  according to an embodiment of the disclosure. 
         [0016]    In one embodiment, STB  10  comprises central processing unit (CPU)  102 . CPU  102  is configured to compute and output control signal according to signal received from remote control  30  or keyboard  31  as control inputs. The control signal comprises channel switch commands and satellite switch control signals. Power transforming module  103  is coupled to CPU  102 , and is configured to obtain system voltage. System voltage is converted to voltage required by satellite antenna receiving device  20  when the satellite antenna receiving device  20  is a multi-polarization type which requires different voltages. Therefore, power transforming module  103  can output different voltages to suit different conditions. For example, power transforming module  103  can convert the system voltage to 13V or 18V. Satellite switching judging module  104  is coupled to CPU  102 , and is configured to receive the channel switch commands. In an embodiment, satellite switching judging module  104  analyzes if target channel is on the same satellite as current channel by checking relevant websites. In other embodiments, current broadcasting channel and other information can be stored in memory device in STB  10 , such as flash memory. Therefore, satellite switching judging module  104  can analyze and make determination by reading the memory device. If the target channel and the current channel are on the same satellite, then satellite switching judging module  104  sends result of determination to CPU  102 . CPU  102  sends a channel switching command to satellite antenna receiving device  20  to switch channels. When the target channel and the current channel are on different satellites, satellite switching judging module  104  sends module driving command to driving controlling module  105 . Driving controlling module  105  is coupled to satellite switching judging module  104  and power transforming module  103 . The driving controlling module  105  receives a command from satellite switching judging module  104 , and sends short circuit detecting command to current detecting module  106 , to detect if the signal line  120  between STB  10  and satellite antenna receiving device  20  is shorted or not. The result of detection is sent to CPU  102 . Driving controlling module  105  also encodes a switch control command according to commands from satellite switching judging module  104  and sends the encoded switch control command to satellite antenna receiving device  20  via signal line  120 . 
         [0017]    Current detecting module  106  is coupled to driving controlling module  105  and power transforming module  103 . The current detecting module  106  is configured to receive command from driving controlling module  105  and detect if signal line  120  is shorted or not. Information as to the detection is sent to driving controlling module  105 . In one embodiment, current detecting module  106  scans voltage of the signal line  120 , the driving controlling module  105  analyzes if it is shorted according to voltage status from current detecting module  106  detected at an output end. For example, when the output voltage is high, driving controlling module  105  determines that signal line  120  is shorted. Conversely, when the output voltage is low, driving controlling module  105  determines that signal line  120  is not shorted. In addition, if the current detecting module  106  does not detect a voltage signal after scanning signal line  120 , the current detecting module  106  generates a voltage signal to signal line  120  via the current detecting module  106  scan end. Then driving controlling module  105  analyzes if the signal line  120  is shorted or not according to the output voltage of current detecting module  106  at an output end. For example, in an embodiment, current detecting module  106  scan end generates a high voltage signal to signal line  120 , then driving controlling module  105  analyzes if signal line  120  is shorted or not according to output voltage signal from current detecting module output end. It should be understood that, the aforesaid method of detecting short circuit is not to limit the scope of the disclosure, current detecting module  106  can send high voltage or low voltage to signal line  120 . Also, it should be understood that, although current detecting module  106  is detecting if the signal line  120  is shorted or not, signal line  120  is electrically connected with STB  10  and satellite antenna receiving device  20 . Thus any part of STB  10  and satellite antenna receiving device  20  which is shorted will be detected by current detecting module  106 . In other embodiments, current detecting module  106  can be set in other location to detect if satellite finding apparatus is shorted or not. 
         [0018]    As shown in  FIG. 2 , CPU  102  is coupled to power transforming module  103  output port and current detecting module  106 . In one embodiment, each module of STB  10  is driven by commands of CPU  102 , such as channel switching command, power switching command, satellite switching command, and so on. In other embodiments, modules can be driven by each other, for example, satellite switching judging module  104  sends switch control command to satellite antenna receiving device  20  via signal line  120  directly. 
         [0019]    As shown in  FIG. 2 , in an embodiment, STB  10  further comprises wireless receiving unit  101  to receive external signal from external control. The wireless receiving unit  101  which is coupled to CPU  102  is configured to send received signal to CPU  102 . In other embodiment, wireless receiving unit  101  can be removed, and STB  10  obtains external signal via other ways. For example, STB  10  can receive external signal by keyboard  31 , through WIFI, ZIGBEE, or other ways. 
         [0020]      FIG. 3  is a configuration schematic diagram of a satellite antenna receiving device  20  according to an embodiment of the disclosure. 
         [0021]    In one embodiment, satellite antenna receiving device  20  comprises protecting switch  201  and switch control module  202 . Switch control module  202  is coupled to protecting switch  201 . Also switch control module  202  and protecting switch  201  are coupled to power transforming module  103 . Switch control module  202  receives switch control command from driving controlling module  105  and decodes the switch control command to control protecting switch  201 . Motor  203  is coupled to protecting switch  201 , and is configured to receive signal from protecting switch  201  and execute corresponding action. Tuner  204  and antenna  205  are coupled to motor  203 . As shown in  FIG. 3 , protecting switch  201  input port is coupled to tuner  204 , so the tuner  204  is coupled to power transforming module  103 . In one embodiment, protecting switch  201  can be switch circuit consisting of transistor and metal oxide semiconductor field effect transistors (MOSFETs). 
         [0022]      FIG. 4  is a process diagram of a satellite finding method according to an embodiment of the disclosure, the method comprises the following steps. 
         [0023]    Step S 10 , CPU  102  decodes received external channel changing command and sends it to satellite switching judging module  104 . The external channel switch command can be signal from keyboard  31 , remote control  30  or other devices; 
         [0024]    Step S 20 , satellite switching judging module  104  analyzes if the target channel and the current channel are on the same satellite. If they are on the same satellite, then step S 201  is executed, otherwise step S 30  is executed; 
         [0025]    Step S 201 , satellite switching judging module  104  returns analytic result to CPU  102  and CPU  102  sends command to satellite antenna receiving device  20  to switch channels; 
         [0026]    Step S 30 , satellite switching judging module  104  sends module driving command to driving controlling module  105  to do short circuit test on signal line  120 . If signal line  120  is shorted, then execute step S 310  and step S 311 , otherwise execute step S 320 ; 
         [0027]    Step S 310  and step S 311 ; driving controlling module  105  alerts CPU  102  that signal line  120  is shorted, and CPU  102  sends command to cut off power for satellite antenna receiving device  20 ; 
         [0028]    Step S 320 , driving controlling module  105  encodes switch control command and sends encoded signal to switch control module  202  to enable protecting switch  201  to power on motor  203 ; 
         [0029]    Step S 40  and step S 401  and step S 402 ; CPU  102  sends satellite switching command, motor  203  rotates polar axis seat to look for and focus on satellite. When satellite is found, CPU  102  sends command to turn off protecting switch  201  to power off motor  203 . 
         [0030]      FIG. 5  is a process diagram of short circuit detection according to an embodiment of the disclosure. In an embodiment, this method comprises the following steps. 
         [0031]    Step  301  and step  302 ; driving controlling module  105  sends short circuit detecting command to current detecting module  106  according to command from satellite switching judging module  104 . Current detecting module  106  detects if voltage exists on signal line  120 . If signal line  120  has voltage then execute step S 304 , otherwise execute step S 303 ; 
         [0032]    Step S 303 , current detecting module  106  sends a high voltage to signal line  120 ; 
         [0033]    Step S 304 , analyzes output voltage from current detecting module  106  output end. If the output voltage is high, the signal line  120  is regarded as shorted. If the output voltage is low, the signal line  120  is regarded as not shorted, then sends analytic result to driving controlling module  105  and CPU  102 . 
         [0034]      FIG. 6  is a diagram of coding scheme of switch controlling command according to an embodiment of the disclosure. The STB  10  and satellite antenna receiving device  20  can communicate via DiSEqC communication protocol. This protocol is used by many satellite programming providers for accomplishing 2-way communication through a coaxial cable. The disclosure is not limited to use of the DiSEqC protocol. Other communication methods and protocols between STBs and satellite antenna components can be used without departing from the scope hereof. In one embodiment, switch control command is based on DiSEqC commands, so it is convenient for switch control module  202  to decode switch control signal. In an embodiment the switch control command is encoding as follows: 
         [0035]    Header: frame header, indicate that following date is switch control command; 
         [0036]    command: define on/off commands; 
         [0037]    P: parity check bit. 
         [0038]    The satellite finding apparatus and satellite finding method only enable the motor when it is necessary to change satellites, when there is no need to change satellites the motor is closed to save energy. Because the motor is disabled most time, so it reduces the risk of being struck by lightning and short circuit by rain soaked, and it will detect if the satellite finding apparatus is shorted before motor enabled to protect apparatus. 
         [0039]    The foregoing description, for purposes of explanation, is with reference to specific embodiments. However, the illustrated embodiments are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The various modifications which are possible within the principles of the disclosure will therefore be protected within the scope of the claims.