Abstract:
A method and system is provided to reinforce wireless communication capabilities between multiple network nodes of an wireless network group. The method and system first detects a wireless transmission capability between a first network node and a second network node. When the wireless transmission capability is lower than a threshold value, one set of reinforcing coordinates will be derived by introducing the first geographic information and the second geographic information. Afterwards, move a third network node to a position with the set of reinforcing coordinates to establish an alternative wireless transmission route between the first network note and second network node. Therefore, when an original wireless transmission route between any two network nodes is abnormal, the alternative wireless transmission route will be available in time and reduce the risks of losing transmission signals.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to wireless communication, in particular, to a method and system for reinforcing wireless network links within a wireless network group. 
     2. Related Art 
     Along with the rapid development of wireless transmission technology, the mass of the transmission wires and cables for connecting a computer with peripheral devices in the past are gradually replaced by wireless transceiver module built in the computer and the peripheral devices. These wireless transceiver modules transmit data between the computer and the peripheral devices according to specific wireless transmission protocols, without any substantial connections. 
     Likewise, two electronic devices or computers having built-in wireless transceiver modules transmit data there-between through wireless transmission, in which the common wireless transmission modes include WiFi, Bluetooth, infrared rays, and so on. Furthermore, through the above wireless transmission modes, Ad-hoc wireless local area network (WLAN) is established by two or more computers. 
     However, a disadvantage of the Ad-hoc WLAN lies in that a wireless transmission distance is not stable enough. For example, the standard IEEE 802.11 has a maximum transmission distance of about 400 meters in theory. However, if the two electronic devices are separated by a concrete wall or other barriers, the transmission distance is greatly reduced to 50 meters or even less than 50 meters. 
     For example, if there is merely one wireless transmission route between a first network node and a second network node, once the wireless transmission route is interrupted, the first network node cannot communicate with the second network node any more due to lack of another alternative wireless transmission route. Therefore, if there is merely one wireless transmission route between the first network node and the second network node, they suffer from an extremely high disconnection risk. 
     Therefore, the conventional Ad-hoc network has the problem of a high communication disconnection risk. 
     SUMMARY OF THE INVENTION 
     To solve the aforesaid problems of the prior art, the present invention provides a system and method for reinforcing the wireless communication capability between multiple network nodes of a wireless network group. When an original wireless transmission route between any two network nodes is abnormal, an alternative wireless transmission route will be available in time and reduce the risks of losing transmission signals. 
     In one aspect of the present invention, a method is provided to reinforce wireless communication capabilities between multiple network nodes of an wireless network group. The method first detects a wireless transmission capability between a first network node and a second network node. When the wireless transmission capability is lower than a threshold value, one set of reinforcing coordinates will be derived by introducing the first geographic information and the second geographic information. Afterwards, move a third network node to a position with the set of reinforcing coordinates to establish an alternative wireless transmission route between the first network note and second network node. 
     In another aspect of the present invention, a system is provided to reinforce wireless communication capabilities between multiple network nodes of an wireless network group. The system includes a detection module, a calculation module and a notification module. The detection module detects a wireless transmission capability between a first network node and a second network node. The calculation module derives at least one set of reinforcing coordinates by introducing first geographic information of the first network node and second geographic information of the second network node when the wireless transmission capability is lower than a threshold value. The notification module is to notify the third network node to move to a position with the set of reinforcing coordinates, to establish an alternative wireless transmission route between the first network node and second network node. 
     These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. It is to be understood that both the foregoing general description and the following detailed description are examples, and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus is not limitative of the present invention, and wherein: 
         FIG. 1A  is a flow chart of a method according to a first embodiment of the present invention; 
         FIG. 1B and 1C  are schematic views of the first embodiment of the present invention; 
         FIG. 2  is a schematic view of a second embodiment of the present invention; 
         FIG. 3A  is a flow chart of a method according to a third embodiment of the present invention; 
         FIG. 3B  is a schematic view of the third embodiment of the present invention; 
         FIG. 4  is a first schematic view of a system according to a fourth embodiment of the present invention; and 
         FIG. 5  is a second schematic view of the system according to the fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description refers to the same or the like parts. 
     All the following embodiments are applicable for a wireless network group with a wireless transmission mode. The wireless network group can be an Ad-hoc WLAN, which includes a plurality of network nodes. The data are transmitted between the network nodes by utilizing a wireless transmission mode, and each network node has geographic information corresponding to a position of each network node. The wireless transmission mode is WiFi, Bluetooth, or infrared rays. Furthermore, the geographic information in each embodiment is one of the following data formats, i.e., global positioning system (GPS) data, assisted global position system (AGPS) data, global positioning system cart (GPSC) data, differential global positioning system (DGPS) data, carrier-phase differential global positioning system (CDGPS) data, Galileo positioning system data, and global navigation satellite system (GLONASS) data. 
     Referring to  FIGS. 1A ,  1  B, and  1 C,  FIG. 1A  is a flow chart of a method according to a first embodiment of the present invention and  FIGS. 1B and 1C  are schematic views of the first embodiment of the present invention. In the first embodiment, the wireless network group includes a plurality of network nodes. These network nodes include a first network node  11 , a second network node  12 , and a movable third network node  13 . At least one initial wireless transmission route  14  exists between the first network node  11  and the second network node  12 . This embodiment includes the following steps. 
     In Step S 10 , detect a wireless transmission capability. The wireless transmission capability between the first network node  11  and the second network node  12  is detected. The wireless transmission capability is defined as the number of wireless transmission routes, a wireless transmission rate, or a combination thereof, between the first network node and the second network node. 
     In Step S 20 , derive at least one set of reinforcing coordinates. At least one reinforcing coordinate is derived by introducing the first geographic information of the first network node  11  and the second geographic information of the second network node  12 . The detailed steps are listed as follows. 
     (1) In Step S 10 , if the wireless transmission capability is defined as the number of wireless transmission routes, the threshold value is defined as a minimum value of the number of initial wireless transmission routes  14  between the first network node  11  and the second network node  12 . When the number of initial wireless transmission routes  14  is less than the threshold value, at least one set of reinforcing coordinate is derived based on the first geographic information of he first network node  11  and the second geographic information of the second network node  12 . 
     (2) In Step S 10 , if the wireless transmission capability is defined as the wireless transmission rate, the threshold value is defined as a minimum transmission rate between the first network node  11  and the second network node  12 . When the wireless transmission rate between the first network node  11  and the second network node  12  is less than the threshold value, at least one set of reinforcing coordinate is derived based on the first geographic information of the first network node  11  and the second geographic information of the second network node  12 . 
     (3) In Step S 10 , if the wireless transmission capability is defined as a combination of the above (1) and (2), when the wireless transmission capability is less than both the threshold values described in the above (1) and (2), at least one set of reinforcing coordinate is derived based on the first geographic information of the first network node  11  and the second geographic information of the second network node  12 . 
     (4) In Step S 10 , if the wireless transmission capability is defined as a combination of the above (1) and (2), when the wireless transmission capability is less than any one of the threshold values described in the above (1) and (2), at least one set of reinforcing coordinate is derived based on the first geographic information of the first network node  11  and the second geographic information of the second network node  12 . 
     In Step S 30 , notify the third network node. The network node  13  is notified to move to a position with the set of reinforcing coordinates. 
     Furthermore, before notifying the third network node  13 , this embodiment further includes a step of searching for a network node having the smallest straight-line distance to a position with the set of reinforcing coordinates in the wireless network group to serve as the third network node  13 . Alternatively, before notifying the third network node  13 , a network node having the smallest path length to a position with the set of reinforcing coordinates is searched in the wireless network group to serve as the third network node  13 . When the network group is located in a spacious geographical environment without any barriers, it is suggested to search for a network node having the smallest straight-line distance to a position with the set of reinforcing coordinates in the wireless network group as the third network node  13 . When the network group is located in an environment having dense buildings or barriers, it is suggested to search for a network node having the smallest path length to a position with the set of reinforcing coordinates as the third network node  13  according to allowable paths among the buildings or barriers. 
     In Step S 40 , establish a wireless transmission route. The third network node  13  arrives at the position with the reinforcing coordinates to establish an alternative first wireless transmission route  15  is established between the first network node  11  and the second network node  12 , so that the data of the first network node  11  are transmitted to the second network node  12  via the third network node  13 , and meanwhile, the data of the second network node  12  are transmitted to the first network node  11  via the third network node  13 . 
     It is noted that, the alternative first wireless transmission route  15  between the first network node  11  and the second network node  12  does not necessarily replace the initial wireless transmission route  14 , and the first wireless transmission route  15  is merely provided for enabling the first network node  11  and the second network node  12  to select to perform wireless transmission via the initial wireless transmission route  14  or the first wireless transmission route  15 . 
     Therefore, in this embodiment, the first wireless transmission route  15  is added to reinforce wireless links between the first network node  11  and the second network node  12 , thereby reducing the disconnection possibility between the first network node  11  and the second network node  12 . 
       FIG. 2  is a schematic view of a second embodiment of the present invention. This embodiment aims at solving the problem that a new wireless transmission route cannot be established between the first network node  11  and the second network node  12  merely depending on the third network node  13 . This embodiment is different from the first embodiment in that, the reinforcing coordinates include a first set of reinforcing coordinates and a second set of reinforcing coordinates. The third network node  13  is notified to move to a position with the first set of reinforcing coordinates. And the wireless network group further includes a movable fourth network node  21 , and the fourth network node  21  is notified to move to another position with the second set of reinforcing coordinates. When the fourth network node  21  arrives at the position with the second set of reinforcing coordinates, the third network node  13  and the fourth network node  21  are connected is series to establish the alternative first wireless transmission route  15  between the first network node  11  and the second network node  12 . 
       FIGS. 3A and 3B  are respectively a flow chart and a schematic view of a method according to a third embodiment of the present invention, which include the following steps. 
     Step S 11  is the same as Step S 10 . 
     In Step S 21 , derive reinforcing coordinates. This step includes all the contents of Step S 20  in the first embodiment, and further derives a first set of reinforcing coordinates and a second set of reinforcing coordinates by introducing the first geographic information of the first network node  11  and the second geographic information of the second network node  12 . 
     In Step S 31 , notify the third network node. The third network node  13  is notified to move to one of the first set of reinforcing coordinates and the second set of reinforcing coordinates. 
     In Step S 41 , notify the fourth network node. The fourth network node  21  is notified to move to another one of the first set of reinforcing coordinates and the second set of reinforcing coordinates. 
     In Step S 51 , establish a wireless transmission route. 
     Through the third network node  13  and the fourth network node  21 , an alternative first wireless transmission route  15  and another alternative second wireless transmission route  32  are respectively established between the first network node  11  and the second network node  12 , so that the first network node  11  and the second network node  12  may select to perform wireless transmission through the initial wireless transmission route  14 , the first wireless transmission route  15 , or the second wireless transmission route  32 , as shown in  FIG. 3B . 
     Besides the first wireless transmission route  15 , this embodiment further adds the second wireless transmission route  32 . Compared with the above embodiments, this embodiment further reinforce the wireless link between the first network node  11  and the second network node  12 , and further reduces the disconnection possibility between the first network node  11  and the second network node  12 . 
     Although only the third network node  13  and the fourth network node  21  in the second and third embodiments are connected in series or in parallel to establish the wireless transmission route, in practice, it can be easily appreciated that, a plurality of network nodes may be connected in series and in parallel to establish a new wireless transmission route. For example, they are connected in series first and then connected in parallel, or they are connected in parallel first and then connected in series, so as to establish a new wireless transmission route. 
       FIG. 4  is a first schematic view of a system according to a fourth embodiment of the present invention, which includes a detection module  41 , a calculation module  42 , and a notification module  43 . This embodiment is illustrated based on the architectures in the first to third embodiments. 
     The detection module  41  is adapted for detecting the wireless transmission capability between the first network node  11  and the second network node  12 , in which the wireless transmission capability is defined in Step S 20  in the first embodiment. 
     The calculation module  42  is for deriving at least one set of reinforcing coordinate by introducing the first geographic information of the first network node  11  and the second geographic information of the second network node  12  when the wireless transmission capability is lower than the threshold value. The calculation manner of the reinforcing coordinates can be obtained with reference to the first, second, and third embodiments. 
     The notification module  43 , as described in Step S 40  in the first embodiment, is adapted for notifying the third network node  13  to move to a position with the reinforcing coordinates. Thus, the third network node  13  arrives at the reinforcing coordinates to establish the alternative first wireless transmission route  15  between the first network node  11  and the second network node  12 . 
     The notification module  43 , as described in the second embodiment, is adapted for notifying the third network node  13  to move to a position with the first set of reinforcing coordinates and the fourth network node  21  to move to another position with the second reinforcing coordinates respectively. Thus, when the third network node  13  arrives at the position with the first set of reinforcing coordinates and the fourth network node  21  arrives at the position with the second set of reinforcing coordinates, the third network node  13  and the fourth network node  21  are connected in series, to establish the alternative first wireless transmission route  15 . 
     The notification module  43 , as described in Step S 41  in the third embodiment, is further adapted for notifying the third network node  13  to move to a position with the first set of reinforcing coordinates and the fourth network node  21  to move to another position with the second set reinforcing coordinates respectively. Thus, when the third network node  13  arrives at the position with the first set of reinforcing coordinates and the fourth network node  21  arrives at the other position with the second reinforcing coordinates respectively, the alternative first wireless transmission route  15  and another alternative second wireless transmission route  32  are respectively established in parallel between the first network node  11  and the second network node  12 . 
     The present invention further includes for a network node having the smallest straight-line distance to a position with the first set of reinforcing coordinates in the wireless network group to serve as the third network node  13 . And, the search module  51  is also adapted for searching for a network node having the smallest straight-line distance to a position with the second reinforcing coordinates to serve as the fourth network node  21 . Alternatively, the search module  51  is adapted for searching for a network node having the smallest path length to a position with the set of the first reinforcing coordinates in the wireless network group to serve as the third network node  13 , and searching for a network node having the smallest path length to another position with the second set of reinforcing coordinates to serve as the fourth network node  21 . 
     When the wireless network group is located in a spacious geographical environment without any barriers, it is suggested to search for a network node having the smallest straight-line distance to the position with the first set of reinforcing coordinates in the wireless network group to serve as the third network node  13  and to search for a network node having the smallest straight-line distance to a position with the second set of reinforcing coordinates in the wireless network group to serve as the fourth network node  21 . When the wireless network group is located in an environment having dense buildings or barriers, it is suggested to search for a network node having the smallest path length to a position with the first set of reinforcing coordinates in the wireless network group to serve as the third network node  13 , and to search for a network node having the smallest path length to another position with the second set reinforcing coordinates in the wireless network group to serve as the fourth network node  21  according to the allowable paths among the buildings or barriers. 
     Additional advantages and modifications will readily occur to those proficient in the relevant fields. The invention in its broader aspects is therefore not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.