Patent Publication Number: US-2016233917-A1

Title: Device for forming wireless high-frequency signal path and method for controlling same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/KR2014/009724 filed on Oct. 16, 2014, which claims priority to Korean Application No. 10-2013-0124147 filed on Oct. 17, 2013, which applications are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a technology that can be applied to a base station including a repeater in a wireless communication (e.g., PCS, Cellular, CDMA, GSM, LTE, etc.) system, and a wireless high-frequency signal path forming device provided to/from a base station antenna and a method for controlling the same. 
     BACKGROUND ART 
     Typically, a base station of a wireless communication system may be divided into a base station main body for processing transmission/reception signals and a base station antenna having a plurality of radiating elements therein and transmitting/receiving a wireless signal. Typically, the base station main body is installed at a lower position on the ground, the base station antenna part is installed at higher position such as a rooftop or a tower, and a power supply cable is connected therebetween. 
     In recent years, thanks to the increase of easy installation of a tower because devices for processing wireless signals are small and light, a structure for installing, at an antenna front end, a remote wireless device such as a Tower Mounted Amplifier (TMA) or a Remote Radio Head (RRH), etc. responsible for the processing of the transmission/reception wireless signal has been widely applied, so as to compensate for cable losses at the time of signal transmission between the antenna and the base station main body. That is, the base station main body for processing the transmission/reception signals is divided into an RF signal processing part and a baseband signal processing part, and only the baseband signal processing part is provided in the base station main body, and the RF signal processing part is provided in a remote wireless device. In this case, the base station main body may be regarded as “baseband signal processing device”. At this time, typically, the transmission/reception signal is transferred between the base station main body (the base band signal processing device) and the remote wireless device by using an optical communication method in order to prevent transmission signal losses therebetween, and a coaxial cable and the like is connected therebewtween in order to supply an operating power to the remote wireless device. 
     On the other hand, a radiation structure of the base station antenna may have various shapes and structures, and currently, a wireless communication antenna generally uses a conventional dual polarized antenna structure by applying a polarization diversity scheme. The dual polarized antenna structure has a structure for generating two linear-polarized waves, also known as, X polarized waves in which a plurality of radiating elements are orthogonal to each other. At least one radiation module made up of such a plurality of radiating elements is arranged on a reflector, typically, multiple radiation modules are elongated arranged in a longitudinal direction so as to form one antenna array. 
     In recent years, the base station antenna may have a multiple antenna structure where multiple antenna arrays are installed on one reflector or installed on each of the reflectors. The multiple antenna structure includes a multi-band antenna structure where multiple antenna arrays based on multiple bands are provided on one reflector or each of the reflectors, (in combination with a multi-band structure) a Multi Input Multi Output (MIMO) structure for each band, or a beam-forming antenna structure, for example, where three or more antenna arrays are arranged in the same band. 
     In addition, the base station antenna may typically include an Antenna Line Device (ALD) such as a Remote Electrical Tilt (RET) device for adjusting a remotely controllable electronical down tilt angle, a Remote Azimuth Steering (RAS) device for remotely adjusting azimuth steering, and a Remote Azimuth Beamwidth (RAB) device for remotely adjusting a beam width of the azimuth. An example of an antenna including the devices is disclosed in Korean Patent Publication No. 10-2010-0122092 first filed by Amphenol Corporation (published on Nov. 19, 2010 and entitled “Multi-beam Antenna with Multi-device Control Unit”; inventors Gregory Girard and Frank Soulie). 
     For control of the RET device, the RAS device, and the RAB device, Antenna Interface Standards Group (AISG) v2.1.0 was recently devised, and a communication scheme through the 3rd Generation Partnership Project (3GPP) protocol was also developed. According to an AISG standard, communication devices are largely divided into a primary station and a secondary station. The primary station part refers to a master part being installed in the base station main body and transmitting a control signal such as MCU, and the secondary station refers to a slave part being installed in the base station antenna side such as RET and an ALD modem and receiving a control signal and performing an operation based on the control signal. 
     As described above, recently, there is a trend in which the base station antenna system has a more complex structure such as a multiple-antenna structure. Many other devices may be additionally installed in the base station antenna system such as a remote wireless device which is installed in the base station antenna part, and various ALDs which are installed inside of the base station antenna system. Therefore, since a number of failures may occur in each device and components inside the device, being installed in a wireless communication system including a base station antenna, measures for keeping the quality of the mobile communication service most stably have been required. In addition, measures for more efficiently controlling various device installed in a wireless communication system including a base station antenna have been required. 
     SUMMARY 
     Therefore, a purpose of the present invention is to provide a wireless high-frequency signal path forming device and a method for controlling the same which can most stably maintain the quality of a mobile communication service by a base station antenna. 
     Another purpose of the present invention is to provide a wireless high-frequency signal path forming device and a method for controlling the same which can more efficiently control a device to be installed in a base station antenna. 
     According to an aspect of the present invention for achieving the above objects, there is provided a wireless high-frequency signal path forming device. The device may include: a plurality of output ends connected so as to correspond to a plurality of antenna arrays, respectively; a plurality of input ends connected so as to correspond to a plurality of amplifiers, respectively; a switching module for forming a path for variably connecting each of the plurality of input ends to one output end selected from the plurality of output ends according to a switching control signal; and a controller for receiving an external command and outputting a switching control signal for controlling a switching operation of the switching module according to the external command. 
     According to another aspect of the present invention, there is provided a method for controlling a path forming device which is a secondary device for performing a control operation by transmitting/receiving a High-level Data-Link Control (HDLC) message based on an Antenna Interface Standards Group (AISG) standard to/from a primary device. The method may include: receiving the HDLC message from the primary device; extracting a predetermined device address and a procedure ID from the received HDLC messages; checking whether the extracted procedure ID is a procedure ID preconfigured with respect to a path configuration between multiple input ends and multiple output ends provided in the path forming device; performing an operation of configuring a path between the multiple input ends and output ends according to the checked procedure ID; and reporting a result of the performance of the operation to the primary device through a response message. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIGS. 1A and 2A  are exemplary block diagrams illustrating a connection state between a base station antenna and remote wireless device which can be considered in connection with the present invention, and  FIGS. 1B and 2B  are graphs illustrating radiation characteristics according to a connection state of  FIGS. 1A and 2A ; 
         FIG. 3A  is a block diagram showing a connection state between a base station antenna and a remote wireless device according to an embodiment of the present invention, and  FIG. 3B  is a graph showing radiation characteristics of  FIG. 3A ; 
         FIGS. 4A, 4B and 4C  are schematic block diagrams of a wireless high-frequency signal path forming device provided on a base station antenna according to a first embodiment of the present invention; 
         FIG. 5  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna according to a second embodiment of the present invention; 
         FIG. 6  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna according to a third embodiment of the present invention; 
         FIG. 7A  and  FIG. 7B  are schematic block diagrams of a wireless high-frequency signal path forming device provided on a base station antenna according to a fourth embodiment of the present invention; 
         FIG. 8  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna according to a fifth embodiment of the present invention; 
         FIG. 9A  and  FIG. 9B  are schematic block diagrams of a wireless high-frequency signal path forming device provided on a base station antenna according to a sixth embodiment of the present invention; 
         FIGS. 10A, 10B, 10C, and 10D  are schematic block diagrams of a wireless high-frequency signal path forming device provided on a base station antenna according to a seventh embodiment of the present invention; 
         FIG. 11  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna according to an eighth embodiment of the present invention; 
         FIG. 12A  and  FIG. 12B  are schematic block diagrams of a wireless high-frequency signal path forming device provided on a base station antenna according to a ninth embodiment of the present invention; 
         FIGS. 13A, 13B, and 13C  are schematic block diagrams illustrating various installation states of a wireless high-frequency signal path forming device according to various embodiments of the present invention; 
         FIG. 14  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna according to a tenth embodiment of the present invention; 
         FIG. 15  is an exemplary format diagram of a device address that is configured for a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention; 
         FIG. 16A  and  FIG. 16B  are exemplary format diagrams of procedures configured for a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention; 
         FIG. 17  is an exemplary format diagram of a transmission frame between a primary device and a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention; 
         FIG. 18A ,  FIG. 18B ,  FIG. 18C , and  FIG. 18D  are examples for values configured to an information field among transmission frames between a primary device and a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention; and 
         FIG. 19  is a flow chart for the control of a wireless high-frequency signal path forming device according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an exemplary embodiment according to the present invention will be described in detail with reference to the accompanying drawings. In the following description, identical elements are provided with an identical reference numeral where possible. Various specific definitions found in the following description are provided only to help general understanding of the present disclosure, and it is apparent to those skilled in the art that the present disclosure can be implemented without such definitions. 
       FIG. 1A  is an exemplary block diagram showing a schematic connection state between a base station antenna having a multiple antenna structure and a remote wireless device that can be considered in connection with the present invention, and  FIG. 1B  is a graph showing radiation characteristics of the base station antenna according to the connection state of  FIG. 1A . Referring to  FIG. 1A , a base station antenna  10 , for example, having sequentially installed four antenna arrays and performing beam forming function, is illustrated in  FIG. 1A . In addition, a remote wireless device (e.g., RRH)  11  is provided outside of the base station antenna  10 , the RRH includes amplifiers for amplifying, with high power, a wireless transmission signal supplied to each of the four antenna arrays, the amplifiers may include for example, amplifiers  1 ,  2 ,  3 , and  4 , and each of the amplifiers is connected so as to correspond to the sequentially installed four antenna arrays, respectively. At this time, beam forming radiation characteristics at the base station antenna having the above structure can be illustrated as shown in  FIG. 1B , and (a) of  FIG. 1B  illustrates the radiation characteristics of a broadcast beam, and (b) of  FIG. 1B  illustrates the radiation characteristics of a service beam. 
     In the structure shown in  FIG. 1A , for example, a case where the amplifier  2  in the remote wireless device  11  is in a failed state (or off) is shown in  FIG. 2A , and the radiation characteristics of the base station antenna in such a case is shown in  FIG. 2B . (a) of  FIG. 2B  shows the radiation characteristics of the broadcast beam, and (b) of  FIG. 2B  shows the radiation characteristics of the service beam. As shown in  FIG. 2B , it can be seen that overall radiation characteristics of the base station antenna has a very poor side lobe characteristics, low directivity, and very poor service quality. 
     As the high power amplifier is one of components having relatively frequent failures, it is likely to cause the above problems according to the failure of the component. To prepare for such a case, a structure may be considered, in which at least one redundant amplifier is added by employing a redundant structure. However, if a component expected to fail is configured as a redundant structure, the structure becomes more complicated, and especially, in the case of an amplifier and a relatively expensive component, the redundant structure is not preferable in terms of cost-effectiveness. 
     Accordingly, in an embodiment of the present invention, as shown in  FIG. 3A , a structure of changing a connection path between each of the amplifiers and a multiple antenna array is proposed.  FIG. 3A  shows a structure for connecting an output path of an amp  1  to a second antenna array in a state where an amplifier  2  has failed (or off) in the remote wireless device  11 , and  FIG. 3B  shows the radiation characteristics of the base station antenna in the structure of  FIG. 3A . (a) of  FIG. 3B  shows the radiation characteristics of the broadcast beam, and (b) of  FIG. 3B  shows the radiation characteristics of the service beam. 
     The structure shown in  FIG. 3A  is a structure for changing the path of the wireless high-frequency signal, so as to operate an antenna array located as close to the center as possible while maintaining a sequential arrangement state of the antenna array operating when an amplifier has failed (that is, when a wireless high-frequency signal provided to a particular antenna array is blocked). As shown in  FIG. 3B , although the first antenna array arranged in the outermost area is not operated, the overall radiation characteristics maintains center-directivity, and thus it can be seen that the overall radiation characteristics of the base station antenna is relatively good. That is, in an embodiment of the present invention, when applying the structure for changing the path of the wireless high-frequency signal, based on the concept as illustrated in  FIG. 3A , it can be found that the service quality at the base station antenna can be maintained as much as possible. Accordingly, when the structure according to the present invention is employed, a somewhat satisfactory service can be provided until defective components or devices are replaced or even in some cases when the defective components or devices are not replaced. 
       FIGS. 4A, 4B, and 4C  are schematic block diagrams of a wireless high-frequency signal path forming device provided to the base station antenna having a multiple antenna structure, according to a first embodiment of the present invention, and  FIG. 4A  illustrates a normal state,  FIG. 4B  illustrates a state where second and third amplifiers have failed, and  FIG. 4C  illustrates a state where the second amplifier has failed. At first, referring to  FIG. 4A , according to a first embodiment of the present invention, a wireless high-frequency signal path forming device  120  is provided between: sequentially installed multiple antenna arrays, for example, first, second, third and fourth antenna array  101 ,  102 ,  103 , and  104 ; and a plurality of amplifiers i.e., the first, second, third and fourth amplifiers  111 ,  112 ,  113 , and  114  for amplifying, with high power, wireless high-frequency signals are individually provided to the first to fourth antenna arrays  101  to  104 , so as to appropriately change and configure, by external control, each path of the wireless high-frequency signals. At this time, the path forming device  120  will be referred to as a ‘Switching Override System (SOS)’. 
     The first to fourth amplifiers  111 ,  112 ,  113 , and  114  may be elements to be provided in the remote wireless device, such as TMA, BTS, a base station, RRH, etc. In addition, the first to fourth antenna arrays ( 101  to  104 ) may be antenna arrays for forming a beam forming antenna structure. 
     The path forming device  120  includes: a plurality of output ends, that is, first to fourth output ends o 1 , o 2 , o 3 , and o 4  connected so as to correspond to the first to fourth antenna arrays  101  to  104 , respectively; a plurality of input ends, that is, first to fourth input ends i 1 , i 2 , i 3 , and i 4  connected so as to correspond to the first to fourth amplifiers  111  to  114 , respectively; and a switching module  1201  for variably connecting each of the first to fourth input ends i 1  to i 4  to one output end selected among the first to fourth output ends o 1  to o 4  according to a switching control signal SC. In addition, the path forming device  120  includes a controller (e.g., CPU)  1202  that receives a command from outside, analyzes the command, and outputs a switching control signal SC for controlling a switching operation of the switching module  1201  according to the command. 
     The switching module  1201  may be formed with the 1-1st to 1-4th switching points S 11 , S 12 , S 13 , and S 14  which connect a first input end i 1  to one of first to fourth output ends o 1  to o 4  and disconnect the connected path; 2-1st to 2-4th switching points S 21 , S 22 , S 23 , and S 24  which connect a second input end i 2  to one of first to a fourth output ends o 1  to o 4  and disconnect the connected path; 3-1st to 3-4th switching points S 31 , S 32 , S 33 , and S 34  which connect a third input end i 3  to one of first to fourth output ends o 1  to o 4  and disconnect the connected path; and 4-1st to 4-4th switching points S 41 , S 42 , S 43 , and S 44  which connect a fourth input i 4  to one of first to fourth output ends o 1  to o 4  and disconnect the connected path. 
     In  FIG. 4A , the connection status of the switching points is shown, in which signals input to the first to fourth input ends i 1 -i 4  are provided to the first to fourth output ends o 1  to o 4 , respectively. Accordingly, each of the signals output from the first to fourth amplifiers  111  to  114  is provided to first to fourth antenna arrays  101  to  104 . 
     In the structure shown in  FIG. 4A , for example, a state where the second and third amplifiers  112  and  113  have failed (or off) is shown in  FIG. 4B .  FIG. 4B  has omitted a representation of the switching module  1201  and controller  1202  shown in  FIG. 4A  for the convenience of explanation. As shown in  FIG. 4B , when the second and third amplifiers  112  and  113  have failed, and if the switching state of the internal switching points of the path forming unit  120  as shown in  FIG. 4A  is maintained, the providing of the wireless high-frequency signal provided to the second and third antenna arrays  102  and  103  located at the center in the entire antenna structure is stopped. To change the above state, as shown in  FIG. 4B , the switching state of the switching points is changed so as to form a path connecting the first input end i 1  and the second output end o 2 , and the switching state of the switching points is changed so as to form a path connecting the fourth input end i 4  and the third output end o 3 . In this case, the path connecting between the second end i 2  and the third input end i 3  is disconnected. Accordingly, a wireless high-frequency signal is provided toward the second and third antenna arrays  102  and  103  located at the center in the entire antenna structure, and the first and fourth antenna arrays  101  and  104  located at the outer side the entire antenna structure are not operated. 
     As shown in  FIG. 4B , in a case where the second and third amplifiers  112  and  113  have failed, in order to operate the second and third antenna arrays  102  and,  103  located at the center in the entire antenna structure, unlike the state as illustrated in  FIG. 4B , in the path forming device  120 , for example, a path can be formed to enable the first input end i 1  and the third output end o 3  to be connected and the fourth input end i 4  and the second output end o 2  to be connected. However, the above case may be undesirable when considering the path length and characteristics of the wireless high-frequency signal in a design of a switch structure in reality, and the switching between the signal path and the closest antenna array may be desirable. 
     Meanwhile, a state where only the second amplifier  112  has failed (or off) in the structure shown in  FIG. 4A , is shown in  FIG. 4C . As shown in  FIG. 4C , when the second amplifier  112  has failed, as shown in  FIG. 4C , the switching state of the switching points is changed so as to form a path connecting the first input end i 1  and the second output o 2 , and an existing path between the second input i 2  and the second output o 2  is disconnected. 
       FIG. 5  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna having a multiple antenna structure according to a second embodiment of the present invention.  FIG. 5  shows an example of N number of antenna arrays greater than four. Further, in  FIG. 5 , a normal state, that is, an example where all amplifiers are in a normal state (an initial state) is shown. 
     As shown in  FIG. 5 , a wireless high-frequency signal path forming device  121  according to a second embodiment of the present invention is provided between: sequentially installed multiple antenna arrays, for example, first, second, third, fourth, . . . , Nth antenna arrays  101 ,  102 ,  103 ,  104 , . . . ,  10 N; and a plurality of amplifiers, for example, the first, second, third, fourth, and Nth amplifiers  111 ,  112 ,  113 ,  114 , and  11 N for amplifying, with high power, wireless high-frequency signals individually provided to the first to Nth antenna arrays  101  to  10 N, so as to appropriately change and configure, by external control, each path of the wireless high-frequency signals. 
     The path forming device  121  includes: a plurality of output ends, that is, first to Nth output ends o 1 , o 2 , o 3 , o 4 , . . . , and oN connected so as to correspond to the first to Nth antenna arrays  101  to  10 N, respectively; a plurality of input ends, that is, first to Nth input ends i 1 , i 2 , i 3 , i 4 , . . . , and iN connected so as to correspond to the first to Nth amplifiers  111  to  11 N, respectively; and a switching module  1211  for variably connecting each of the first to Nth input ends i 1  to iN to one output end selected among the first to Nth output ends o 1  to oN according to a switching control signal. In addition, the path forming device  121  may include a controller (not shown) which receives a command from outside, analyzes the command, and outputs a switching control signal for controlling a switching operation of the switching module  1201  according to the command. 
     The switching module  1211  includes the 1-1st to 1-Nth switching points S 11 , S 12 , S 13 , S 14 , . . . and S 1 N for connecting a path between the first input end i 1  and one output end among the first to Nth output ends of to oN, or disconnect the connected path. Similarly, 2-1st to 2-Nth switching points S 21 , S 22 , S 23 , S 24 , . . . , S 2 N for the second input end i 2  and; 3-1st to 3-Nth switching points S 31 , S 32 , S 33 , . . . , S 34  for the third input i 3 ; and 4-1st to 4-Nth switching points S 41 , S 42 , S 43 , S 44 , . . . , S 4 N for the fourth input end i 4 , N-1th to N-Nth switching points SN 1 , SN 2 , SN 3 , SN 4 , . . . , SNN for the Nth input end iN, and the like can be formed. 
       FIG. 6  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna having a multiple antenna structure according to a third embodiment of the present invention.  FIG. 6  shows an example of N number of antenna arrays like  FIG. 5 . In addition, in the example of  FIG. 6 , the path forming device is designed to be divided into two sub-devices, that is, a first sub-path forming device  120 - 1 , and a second sub-path forming device  120 - 2 . Further, in  FIG. 6 , an example where the first and second sub-path forming devices  120 - 1  and  120 - 2  are mechanically installed inside the base station antenna  10  is illustrated. 
     An overall appearance of the base station antenna  10  is formed through a radome which corresponds to the conventional mechanical outer cover, an upper cap, and a lower cap, and the plurality of antenna arrays  101 - 10 N can be installed therein. At this time, the lower cap includes a plurality of input and output ports for inputting and outputting the wireless high-frequency signal, a control signal, etc., and the first and second sub-path forming devices  120 - 1  and  120 - 2  may be configured to receive output signals from the first to Nth amplifiers  111  to  11 N through the first to Nth ports P 1  to PN. In addition, in this case, the first to Nth amplifiers  111  to  11 N may be provided in the remote wireless device which is installed at the front end of the base station antenna  10 . 
     The whole N number of antenna arrays  101  to  10 N may be divide into two groups, and the first sub-path forming device  120 - 1  may be configured to be in charge of, for example, first to N/2th antenna arrays  101  to  10 [N/2] disposed on the left part, and the second sub-path forming device  120 - 2  may be configured to be in charge of a [N/2+1]th to Nth antenna arrays  10 [N/2+1] to  10 N disposed on the right part of the whole N number of antenna arrays  101  to  10 N. 
     In the structure shown in  FIG. 6 , when N=8, that is, the total number of antenna arrays is eight, the first and second sub-path forming devices  120 - 1  and  120 - 2  are in charge of four antenna arrays each. In addition, in such a case, it will be appreciated that the first and second sub-path forming devices  120 - 1  and  120 - 2  may have the same structure as the path forming device  120  according to the first embodiment as shown in the  FIG. 4A . Alternatively, the first and second sub-path forming devices  120 - 1  and  120 - 2  may have a structure similar to that of a path forming device  122  according to a fourth embodiment shown in  FIG. 7A . 
       FIGS. 7A and 7B  are schematic block diagrams of a wireless high-frequency signal path forming device provided on the base station antenna having a multiple antenna structure, according to a fourth embodiment of the present invention, and  FIG. 7A  illustrates a normal state, and  FIG. 7B  illustrates a state where second and third amplifiers have failed. A path forming device  122  according to a fourth embodiment of the invention shown in  FIGS. 7A and 7B   122  may have the same structure as, for example, the case where the first sub-path forming device  120 - 1  shown in  FIG. 6  is in charge of four antenna arrays. 
     The above embodiments have been described that, when any amplifier has failed, the path between the amplifiers and the plurality of antenna arrays is changed and configured so as to maintain the operation of the antenna arrays possibly-located in the center among a plurality of antenna arrays. In this case, for example, an antenna array disposed on the outermost area (that is, the first antenna array) may not necessarily be connected to an amplifier other than an amplifier (first amplifier) having a path connected thereto. A structure according to the fourth embodiment of the present invention shown in  FIGS. 7A and 7B  shows an example that can be applied to the above case. 
     At first, referring to  FIG. 7A , when describing a configuration of the path forming device  122  according to the fourth embodiment of the present invention in more detail, the path forming device  122 , like the configuration of the previous embodiments, is provided between sequentially installed first, second, third and fourth antenna arrays  101 ,  102 ,  103 , and  104  and first, second, third and fourth amplifiers  111 ,  112 ,  113 , and  114  for amplifying, with high power, wireless high-frequency signals individually provided to the first to fourth antenna arrays  101  to  104 , so as to appropriately change and configure, by an external control, each of the paths of the wireless high-frequency signals. In addition, the path forming unit  122  includes: first to a fourth output ends o 1 , o 2 , o 3 , and o 4  connected so as to correspond to the first to fourth antenna arrays  101  to  104 , respectively; first to a fourth input ends i 1 , i 2 , i 3 , and i 4  connected to correspond to the first to fourth amplifiers  111  to  114 , respectively; and a switching module  1221  for variably connecting each of the first to fourth input ends i 1  to i 4  to one output end selected from the first to fourth output ends o 1  to o 4  according to a switching control signal. In addition, the path forming device  120  may include a controller (not shown) which receives a command from outside, analyzes the command, and outputs a switching control signal for controlling a switching operation of the switching module  1221  according to the command. 
     At this time, referring to the detailed configuration of the switching module  1221 , unlike the previous embodiments, the switching module  1221  may be formed with: 1-1st to 1-4th switching points S 11 , S 12 , S 13 , and S 14  which connect a first input end i 1  to one of first to fourth output ends o 1  to o 4  and disconnect the connected path; 2-2nd to 2-4th switching points S 22 , S 23 , and S 24  which connect a second input end i 2  to one of second to fourth output ends o 2  to o 4  and disconnect the connected path; 3-3rd and 3-4th switching points S 33  and S 34  which connect a third input end i 3  to either a third or fourth output ends o 3  and o 4  and disconnect the connected path; and a 4-4th switching point S 44  which connects a fourth input i 4  to a fourth output end o 4  and disconnect the connected path. 
     In the structure shown in  FIG. 7A , for example, the state where the second and fourth amplifiers  112  and  114  have failed (or off) is shown in  FIG. 7B .  FIG. 7B  has omitted a representation of the switching module  1221  shown in  FIG. 4A  for the convenience of explanation. As shown in  FIG. 7B , when the second and fourth amplifiers  112  have failed, as shown in  FIG. 7B , the switching state of the switching points is changed so as to form a path connecting the first input end i 1  and the third output end o 3 , and the switching state of the switching points is changed so as to form a path connecting the third input end i 3  and the fourth output end o 4 . In this case, the path connecting between the second input end i 2  and the fourth input end i 4  is disconnected. 
     It can be seen that the switching state of the switching points shown in  FIG. 7B  is a state where a wireless high-frequency signal is provided toward the third and fourth array antennas  103  and  104  in the whole antenna structure. The switching state may be appropriate when assuming a case where the path forming device  122  according to the fourth embodiment shown in  FIGS. 7A and 7B  is applied to the first sub-path forming device  120 - 1  shown  FIG. 6 . It should be understood that the case is applicable when the first sub-path forming device  120 - 1  is in charge of four antenna arrays. In addition, it will be appreciated that the second sub-path forming device  120 - 2  shown in  FIG. 6  also may be implemented similar to that shown in  FIG. 7A . 
     Further, as well as the structure of the switching module  1221  shown in  FIG. 7A , for example, when targeting only four antenna arrays, the switching module may be implemented by the configuration of only enabling the first input end i 1  connected to the first amplifier  111  to be connected to the second output end o 2 , and enabling the fourth input end i 4  connected to the fourth amplifier  114  to be connected to the third output end o 3 . 
       FIG. 8  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna having a multiple antenna structure according to a fifth embodiment of the present invention.  FIG. 8  shows an example of N number of antenna arrays greater than four. Further, in  FIG. 8 , a normal state, that is, an example where all amplifiers are in a normal state (an initial state) is shown. 
     As shown in  FIG. 8 , a wireless high-frequency signal path forming device  123  according to a fifth embodiment of the present invention is provided between sequentially installed first, second, third, fourth, . . . , [N/2]th antenna arrays  101 ,  102 ,  103 ,  104 , . . . ,  10 [N/2] and first, second, third, fourth, and [N/2]th amplifiers  111 ,  112 ,  113 ,  114 , and  11 [N/2] for amplifying, with high power, wireless high-frequency signals individually provided to the first to Nth antenna arrays  101  to  10 [N/2], so as to appropriately change and configure by external control, each path of the wireless high-frequency signals. 
     The path forming device  123  includes: a plurality of output ends, that is, first to [N/2]th output ends o 1 , o 2 , o 3 , o 4 , . . . , and o[N/2] connected so as to correspond to the first to [N/2]th antenna arrays  101  to  10 [N/2], respectively; a plurality of input ends, that is, first to [N/2]th input ends i 1 , i 2 , i 3 , i 4 , . . . , and i[N/2] connected so as to correspond to the first to [N/2]th amplifiers  111  to  11 [N/2], respectively; and a switching module  1231  for variably connecting each of the first to [N/2]th input ends i 1  to i[N/2] to one output end selected among the first to [N/2]th output ends o 1  to o[N/2] according to a switching control signal. In addition, the path forming device  123  may include a controller (not shown) which receives a command from outside, analyzes the command, and outputs a switching control signal for controlling a switching operation of the switching module  1231  according to the command. 
     The switching module  1231  includes the 1-1st to 1-[N/2]th switching points S 11 , S 12 , S 13 , S 14 , . . . and S 1 [N/2] for connecting a path between the first input end i 1  and one output end among the first to [N/2]th output ends o 1  to o[N/2], or disconnect the connected path. In addition, the 2-2nd to 2-[N/2]th switching points S 22 , S 23 , S 24 , . . . , S 2 [N/2] for the second input end i 2 , and 3-3th to 3-[N/2]th switching points S 33 , S 34 , . . . , S 3 [N/2] for the third input i 3 , and 4-4th to 4-[N/2]th switching points S 44 , . . . , S 4 N for the fourth input end i 4 , a [N/2]th switching point SNN for the [N/2]th input end i[N/2], and the like can be formed. 
     The path forming device  1221  according to the fifth embodiment shown in  FIG. 8  may be appropriate when assuming the case where the path forming device  1221  according to the fifth embodiment shown in  FIG. 8  is applied to the first sub-path forming device  120 - 1  shown  FIG. 6 . In addition, it will be appreciated that the second sub-path forming device  120 - 2  shown in  FIG. 6  also may be implemented similar to that shown in  FIG. 8 . 
       FIGS. 9A and 9B  are schematic block diagrams of a device for forming a wireless high-frequency signal path provided to the base station antenna having a multiple antenna structure, according to a sixth embodiment of the present invention, wherein  FIG. 9A  illustrates a normal state, and  FIG. 9B  illustrates a state where second and third amplifiers have failed. The path forming device  124  according to a sixth embodiment of the present invention shown in  FIG. 9A  and  FIG. 9B  is similar to most of the structure of the embodiments shown in  FIG. 4A  or  FIG. 7A , and shows a more detailed example implementable for the switching module.  FIGS. 9A and 9B  primarily show a detailed configuration of the switching module for the convenience of description, and omit showing the other configuration. Further, in the inside of the path forming device  124  of  FIGS. 9A and 9B , the currently connected path is indicated by a solid line, and a disconnected path is indicated by a dotted line. 
     As shown in  FIGS. 9A and 9B , the path forming device  124  according to the sixth embodiment of the present invention may be implemented as a connection structure of four Single-Pole Double Throw (SPDT) switches. That is, the path forming device  124  is provided with a switch which is installed on the first input end i 1  and connects the first input end i 1  to the first or second output end of or o 2 , and a switch which is installed on the fourth input end i 4  and connect the fourth input end i 4  to the third or fourth output end o 3  or o 4 . In addition, in order to perform impedance matching between the input end and the output end, the path forming device  124  is provided with a switch which is installed on the second output end o 2  and connects the second output end o 2  to the first or second input end i 1  or i 2 ; and a switch which is installed on the third output end o 3  and connects the third output end o 3  to the third or fourth input end i 3  or i 4 . 
       FIG. 9A  shows the status of each of the switches such that the first to fourth input ends i 1  to i 4  are connected so as to correspond to the first to fourth output ends of to o 4 , respectively. In this situation, for example, when the second and third amplifiers  112  and  113  have failed, as shown in  FIG. 9B , each of the switches may perform a switching operation of connecting the first input end i 1  to the second output end o 2  and connecting the fourth input end i 4  to the third output end o 3 . 
       FIGS. 10A, 10B, 10C, and 10D  are schematic block diagrams of a wireless high-frequency signal path forming device provided on the base station antenna having a multiple antenna structure, according to a seventh embodiment of the present invention.  FIG. 10A  illustrates a normal state,  FIG. 10B  illustrates a state where second, third, and fifth amplifiers have failed, and  FIGS. 10C and 10D  illustrate a state where the fourth and fifth amplifiers have failed. The wireless high-frequency signal path forming device  125 , according to the seventh embodiment of the present invention shown in  FIGS. 10A to 10D , is most similar to the structure of the first embodiment shown in  FIG. 5  or  FIG. 8  except that the number of the antenna array is eight, and shows a more detailed example implementable for the switching modules. Further, in the inside of the path forming device  125  of  FIGS. 10A to 10D , the currently connected path is indicated by a solid line, and a disconnected path is indicated by a dotted line. 
     As shown in  FIGS. 10A and 10D , the path forming device  125  may be implemented with four SPDT switches, four Single-Pole 3 Throw (SP3T) switches, and four Single-Pole 4 Throw (SP4T) switches. That is, the path forming device  125  is provided with: an SP4T switch which is installed on the first input end i 1  and connects the first input end i 1  to the first, second, third, or fourth output ends o 1 , o 2 , o 3 , or o 4 ; an SP3T switch which is installed on the second input end i 2  and connects the second input end i 2  to the second, third, or fourth output ends o 2 , o 3 , or o 4 ; an SPDT switch which is installed on the third input end i 3  and connects the third input end i 3  to the third or fourth output ends o 3  or o 4 ; an SP4T switch which is installed on the eighth input end i 8  and connects the eighth input end i 8  to the eighth, seventh, sixth, or fifth output ends o 8 , o 7 , o 6 , or o 5 ; an SP3T switch which is installed on the seventh input end i 7  and connects the seventh input end i 7  to the seventh, sixth, or fifth output ends o 7 , o 6 , or o 5 ; and an SPDT switch which is installed on the sixth input end i 6  and connects the sixth input end i 6  to the sixth or fifth output ends o 6  or o 5 . In addition, the path forming device  125  is provided with an SP4T switch which is installed on the fourth output end o 4  and connects the fourth output end o 4  to the first, second, third, or fourth input ends i 1 , i 2 , i 3 , or i 4 ; an SP3T switch which is installed on the third output end o 3  and connects the third output end o 3  to the first, second, or third input ends i 1 , i 2 , or i 3 ; an SPDT switch which is installed on the second output end o 2  and connects the second output end o 2  to the first or second input ends i 1  or i 2 ; the SP4T switch which is installed on the fifth output end o 5  and connects the fifth output end o 5  to the fifth, sixth, seventh, or eighth input ends i 5 , i 6 , i 7 , or i 8 ; the SP3T switch which is installed on the sixth input end i 6  and connects the sixth output end i 6  to the sixth, seventh or eighth input ends i 6 , i 7 , or i 8 ; and the SPDT switch which is installed on the seventh output end o 7  and connects the seventh output end o 7  to the seventh or eighth input ends i 7  or i 8 . 
       FIG. 10A  shows the status of the switch such that the first to eighth input ends i 1  to i 8  correspond to the first to eighth output ends o 1  to o 8 , respectively. In this situation, for example, when the second, third, and fifth amplifiers  112 ,  113 , and  115  have failed, as shown in  FIG. 10B , each of the switches may perform a switching operation of connecting the first input end i 1  to the third output end o 3 , connecting the sixth input end i 6  to the fifth output end o 5 , and connecting the eighth input ends i 8  to the sixth output end o 6 . Accordingly, the third, fourth, fifth and sixth antenna arrays  103 ,  104 ,  105 , or  106  located at the center thereof are implemented to maintain the operation. 
     In the state shown in  FIG. 10A , for example, when the fourth and fifth amplifiers  114  and  115  have failed, as shown in  FIG. 10C , each of the switches may perform a switching operation of connecting the first input end i 1  to the fourth output end o 4  and connecting the eighth input end i 8  to the fifth output end o 5 . In addition, as shown in  FIG. 10D , for example, each switch may perform a switching operation of connecting the first input end i 1  to the second output end o 2 , connecting the second input end i 2  to the third output end o 3 , connecting the third input end i 3  to the fourth output end o 4 , connecting the eighth input end i 8  to the seventh output end o 7 , connecting the seventh input end i 7  to the sixth output end o 6 , and connecting the sixth input end i 6  to the fifth output end o 5 . 
     On the other hand, when referring to the structure shown  FIG. 9A  to  FIG. 10D , for example, in another embodiment of the invention, it can be seen that N/2 number of switches, i.e., the SP[N/2]T switch, the SP[N/2−1]T switch, . . . the SPDT switch, are required as switching elements for actually implementing the path forming device. 
       FIG. 11  is a schematic block diagram of a wireless high-frequency signal path forming device provided on a base station antenna having a multiple antenna structure according to an eighth embodiment of the present invention. The structure of a path forming device according to an eighth embodiment of the present invention shown in  FIG. 11  is logically identical to that of the seventh embodiment shown in  FIG. 10A to 10D , however,  FIG. 11  shows a state where the path forming device is designed to be divided into two sub-devices that can be symmetrically configured, that is, a first sub-path forming device  125 - 1  and a second sub-path forming device  125 - 2 . That is, the first sub-path forming device  125 - 1  may be configured to divide the first to eighth antenna arrays  101  to  108  into two groups, and be in charge of the first to fourth antenna arrays  101  to  104  arranged on the left side, and the second sub-path forming device  125 - 2  may be configured to be in charge of the fifth to eighth antenna arrays  105  to  108  arranged on the right part of the first to eighth antenna arrays  101  to  108 . 
       FIGS. 12A and 12B  are schematic block diagrams of a wireless high-frequency signal path forming device provided on the base station antenna having a multiple antenna structure, according to a ninth embodiment of the present invention, and  FIG. 12A  illustrates a normal state, and  FIG. 12B  illustrates a state where the fourth, fifth, and sixth amplifiers have failed. The structure of a path forming device according to the ninth embodiment of the present invention shown in  FIG. 12  is logically identical to that of the eighth embodiment shown in  FIG. 11 , however,  FIG. 11  shows an example where the first and second sub-path forming devices  126 - 1  and  126 - 2  are mechanically installed inside the base station antenna  10 . 
     For example, the first sub-path forming device  126 - 1  may be configured to receive output signals from the first to fourth amplifiers  111  to  114  through first to fourth ports P 1  to P 4  formed on the base station antenna  10 , and the second sub-path forming device  126 - 2  may be configured to receive output signals from the fifth to eighth amplifiers  115  to  118  through a fifth to eighth ports P 5  to P 8  formed on the base station antenna  10 . 
       FIG. 13A ,  FIG. 13B  and  FIG. 13C  are schematic block diagrams illustrating a variety of installation states of a wireless high-frequency signal path forming device provided on the base station antenna having a multiple antenna structure in accordance with embodiments of the present invention, and  FIG. 13A  shows a state where the path forming device  120  is mechanically installed inside the base station antenna  10 ,  FIG. 13B  shows a state where the path forming device  120  is separately installed between the base station antenna  10  and the remote wireless device  11 . In addition, as shown in  FIG. 13C , the path forming device  120  may also be mechanically installed inside the remote wireless device  11 . That is, the most desirable case is that the path forming device  120  is installed between the antenna  10  and the amplifier on the route, and various positions such as inside the antenna, RRH, etc. are available for the mechanical installation position. 
       FIG. 14  is a schematic block diagram of a wireless high-frequency signal path forming device provided on the base station antenna having a multiple antenna structure in accordance with a tenth embodiment of the present invention, and the path forming device  120  shown in  FIG. 14  may have the same structure as that of other embodiments, and may be installed to receive an external command for a path forming operation, for example, through another ALD  15  connected in a daisy-chain fashion through an AISG cable, etc. 
     On the other hand, the path forming device  120  shown in  FIG. 14  is shown to be installed inside the base station antenna  10 , but may also be installed outside the base station antenna  10 , for example, at the front end of the base station antenna  10 . 
     In the following description, a detailed method for performing the path forming operation, by the path forming device which can be configured as the embodiments of the present invention, according to a command provided from the outside, for example, the base station main body, will be described. At this time, the communication scheme between the path forming device and the external control device according to the present invention proposes a communication scheme which can be compatible with the AISG standard. That is, an embodiment of the present invention proposes a communication scheme in which the base station main body is considered as the primary device according to the AISG standard, and the path forming device is considered as the secondary device according to the AISG standard. 
       FIG. 15  is an example format diagram of a code of a device that is configured for a secondary device and handles the corresponding path forming device as the secondary device in accordance with an AISG standard, in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention. Referring to  FIG. 15 , at first, the path forming device according to the present invention, also known as “SOS” may have a predetermined value as device identification information, that is, a device code, for example, “0x29 [hexadecimal code]” value. 
       FIG. 16A  and  FIG. 16B  are exemplary format diagrams of procedures configured for a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention,  FIG. 16A  illustrates an example of procedures to be applied in the path forming device of the present invention, so as to correspond to common commands prescribed according to an AISG standard for the conventional ALD, and  FIG. 16B  illustrates an example of procedures corresponding to the path forming device-specific operation command according to the present invention. 
     First, referring to  FIG. 16A , for the operation procedures such as an alarm display, an active alarm clear, alarm condition acquisition, the number of sub-units acquisition of the path forming device, etc., procedures also known as, “SOSAlarmIndication”, “SOSClearActiveAlarms”, “SOSGetAlarmStatus”, “SOSGetNumberOfSubunits”, etc. can be defined, and identification code values thereof can be defined as “0x76”, “0x77”, “0x78”, “0x79”, respectively. Respective identification code values may be used by overloading the conventionally defined TMA procedures and the identification code value thereof, in order to prevent table waste of a common command table configured in the AISG standard. 
     Next, referring to  FIG. 16B , a procedure for instructing to set the path as the initial state, also known as “SOSSetSwitchReset” procedure, can be defined in the path forming device according to an embodiment of the present invention, and the identification code value can be defined as “0x70”. The “SOSSetSwitchReset” procedure corresponds to, for example, an operating procedure that returns all the switches to the initial value of the manufacturing process. 
     In addition, a procedure for instructing to notify the current path configuration state, also known as “SOSGetSwitchStatus” procedure, can be defined in the path forming device, and the identification code value may be defined as “0x71”. The “SOSGetSwitchStatus” procedure corresponds to an operation procedure for checking output ends with respect to all input ends, for example, the operation procedure of checking an output end connected to a first input end, an output end connected to a second input end, . . . , an output end connected to a Nth input end is performed. 
     In addition, a procedure for designating an output end connected to a particular input end, also known as “SOSSetSwitchPort” procedure, can be defined in the path forming device, and the identification code value may be defined as “0x72”. In addition, a procedure for instructing to display an output end connected to a particular input end, also known as “SOSGetSwitchPort” procedure, can be defined in the path forming device, and the identification code value may be defined as “0x73”. 
       FIG. 17  is an exemplary diagram of a transmission frame between a primary device and a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention. Referring to  FIG. 17 , the procedures defined as shown in  FIGS. 16A and 16B  can be performed by carrying out communication between the primary device and the secondary device (that is, the path forming device) through a transmission frame according to the AISG standard. 
     The transmission frame between the primary device and the secondary device may be set to a start flag field (Flag, one octet), an Address field (Device Address, one octet), a control fields (Control, one octet), an information field (INFO, one octet), an error correction field (CRC: two octets), and an end flag field (Flag, one octet) according to the conventional AISG standard. 
     In addition, the information field may be configured as a procedure ID field of one octet (Procedure ID), a frame length field of two octets (Number of data octets: low octet+high octet), and a data octet field having a variable length (Data octets). The values of the procedure ID field are configured procedure ID values as shown in  FIGS. 16A and 16B . 
       FIGS. 18A, 18B, 18C, and 18D  are exemplary diagrams for values to be configured in the information field of the transmission frame between a primary device and a secondary device in order to control a wireless high-frequency signal path forming device according to an embodiment of the present invention,  FIG. 18A  shows an example of values associated with a “SOSSetSwitchReset” procedure,  FIG. 18B  shows an example of values associated with a “SOSGetSwitchStatus” procedure,  FIG. 18C  shows an example of values associated with a “SOSSetSwitchPort” procedure, and  FIG. 18D  shows an example of values associated with a “SOSGetSwitchPort” procedure. 
     First, referring to  FIG. 18A , (a) of  FIG. 18A  shows an example of values of the information field corresponding to the command to perform a “SOSSetSwitchReset” procedure transmitted from the primary device to the secondary device. As shown in (a) of  FIG. 18A , the information field is defined by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and the like. The procedure ID value is set to ‘0x70’ as shown in  FIG. 16B , and the frame length value is set to ‘0x01, 0x00’ since the length of a data octet at a rear end of the corresponding frame length field is one octet. The sub-unit value is set to include one or more sub-units in the AISG standard, and accordingly the sub-unit value is set to a default value of ‘0x01’ in (a) of  FIG. 18A . 
     (b) and (c) of  FIG. 18A  show examples of the information field which can be included in the response message according to a command to perform a “SOSSetSwitchReset” procedure transmitted from the secondary device to the primary device, (b) of  FIG. 18A  corresponds to a message notifying of the normal performance of the operation, and (c) of  FIG. 18A  corresponds to a message notifying of the failure in performance of the operation. As shown in (b) of  FIG. 18A , the information field may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. In this case, the return code value may be set to, for example, “0x00” representing the normal performance of the operation (OK). 
     Referring to (c) of  FIG. 18A , the information field for informing of a performance failure of the operation for the command to perform a “SOSSetSwitchReset” procedure may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. At this time, the return code value includes, for example, ‘0x0B’ of one octet representing the failure in performance of the operation (Fail). A value of at least one octet for representing more detailed information on the failure in performance of the operation may be additionally set in the return code field. For example, the value is set to “0x25” representing an unsupported procedure in (c) of  FIG. 18A . 
     Next, referring to  FIG. 18B , (a) of  FIG. 18B  shows an example of values of the information field corresponding to a command to perform a “SOSGetSwitchStaus” procedure transmitted from the primary device to the secondary device. As shown in (a) of  FIG. 18B , the information field is defined by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and the like. The procedure ID value is set to ‘0x71’ as shown in  FIG. 16B , and the frame length value is set to ‘0x01, 0x00’ since the length of a data octet at a rear end of the corresponding frame length field is one octet. A sub-unit value is set to the default value of ‘0x01’. 
     (b), (c), and (d) of  FIG. 18B  show examples of the information field which can be included in the response message according to a command to perform a “SOSGetSwitchStatus” procedure transmitted by the primary device from the secondary device, (b) of  FIG. 18B  corresponds to a message notifying of the normal performance of the operation, (c) of  FIG. 18B  corresponds to another example of a message notifying of the normal performance of the operation, and (d) of  FIG. 18B  corresponds to a message notifying of the failure in performance of the operation. As shown in (b) of  FIG. 18B , the information field may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, a return code value of one octet, and response code values of multiple octets notifying of the connection state of input and output ends. 
     In this case, the return code value may be set to, for example, “0x00” representing the normal performance of the operation (OK). In addition, the response code value may be configured to sequentially represent input ends and output ends associated therewith. That is, in an example shown in (b) of  FIG. 18B , an exemplary response code value is illustrated as ‘0x01 0x01 0x02 0x02 0x03 0x03 0x04 0x04’, which sequentially represents the first input end and an output end connected thereto (that is, the first output end), the second input end and an output end connected thereto (that is, the second output end), the third input end and an output end connected thereto (that is, the third output end), and the fourth input end and an output end connected thereto (that is, the fourth output end). In this response code, it can be seen that the current path forming device is a structure having four input/output ends corresponding to the current four array antenna. 
     On the other hand, (c) of  FIG. 18B  shows another example of a message notifying of the normal performance of the operation, unlike the example with the above-mentioned (b) of  FIG. 18B , an exemplary response code value is illustrated as ‘0x01 0x02 0x02 0x03 0x03 0x04 0x00’, which represents that an output end connected to the first input end is the second output end, an output end connected to the second input end is the third output end, an output end connected to the third input end is the fourth output end, and the fourth output end is in an pen state (that is, for example, represented as ‘0x00’). 
     Referring to (d) of  FIG. 18B , the information field for informing of a performance failure for the command to perform a “SOSGetSwitchStatus” procedure may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. At this time, the return code value includes, for example, ‘0x0B’ of one octet indicating the failure in performance of the operation (Fail). A value of at least one octet for representing more detailed information on the failure in performance of the operation may be additionally set in the return code field. For example, the value is set to “0x25” representing an unsupported procedure in (d) of  FIG. 18B . 
     Next, referring to  FIG. 18C , (a) of  FIG. 18C  shows an example of values of the information field corresponding to a command to perform a “SOSSetSwitchPort” procedure transmitted by the secondary device from the primary device. As shown in (a) of  FIG. 18C , the information field is defined by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and input/output end individually having one octet. The procedure ID value is set to ‘0x72’ as shown in  FIG. 16B , and the frame length value is set to ‘0x03, 0x00’ since the length of a data octet at a rear end of the corresponding frame length field is three octets. A sub-unit value is set to the default value of ‘0x01’. Further, values of the input end and output end are values representing the switching of a designated input end to a designated output end, and in (a) of  FIG. 18C  shows an exemplary value of ‘0x01 0x02’ which instructs to connect the first input end to the second input end. 
     (b) and (c) of  FIG. 18C  show examples of the information field which can be included in the response message according to the command to perform a “SOSGetSwitchStatus” procedure transmitted from the secondary device to the primary device, (b) of  FIG. 18C  corresponds to a message notifying that the normal operation is performed, and (c) of  FIG. 18C  corresponds to a message notifying of the failure in perform of the operation. As shown in (b) of  FIG. 18C , the information field may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. In this case, the return code value may be set to, for example, “0x00” representing the normal performance of the operation (OK). 
     Referring to (c) of  FIG. 18C , the information field for informing of a performance failure for the command to perform a “SOSGetSwitchStatus” procedure may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. At this time, the return code value includes, for example, a ‘0x0B’ of one octet representing the failure in performance of the operation (FAIL), and a value of at least one octet for representing more detailed information on the failure in performance of the operation may be additionally set in the return code field. 
     Next, referring to  FIG. 18D , (a) of  FIG. 18D  shows an example of values of the information field corresponding to the command to perform a “SOSGetSwitchPort” procedure transmitted by the secondary device from the primary device. As shown in (a) of  FIG. 18D , the information field is defined by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and input/output ends individually having one octet. The procedure ID value is set to ‘0x73’ as shown in  FIG. 16B , and the frame length value is set to ‘0x02, 0x00’ since the length of a data octet at a rear end of the corresponding frame length field is two octets. A sub-unit value is set to the default value of ‘0x01’. Further, the value of the input end is a value for displaying an output end connected to a designated input end, and (a) of  FIG. 18D  shows an exemplary value of ‘0x01’ which instructs to notify of an output end connected to the first input end. 
     (b) and (c) of  FIG. 18D  show examples of the information field which can be included in the response message according to the command to perform a “SOSGetSwitchPort” procedure transmitted by the primary device from the secondary device, (b) of  FIG. 18D  corresponds to a message notifying that the normal operation is performed, and (c) of  FIG. 18D  corresponds to a message notifying of the failure in performance of the operation. As shown in (b) of  FIG. 18D , the information field may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and an output value of one octet. A value of an output end is a value for displaying an output end connected to designated input end, and in (b) of  FIG. 18D  shows an exemplary value of ‘0x02’ which instructs to notify that an output end connected to the first input end is the second output end. 
     Referring to (c) of  FIG. 18D , the information field for informing of a performance failure for the command to perform a “SOSGetSwitchPort” procedure may be set by including a procedure ID value of one octet, a frame length value of two octets, a sub-unit value of one octet, and a return code value of one octet. At this time, the return code value includes, for example, a ‘0x0B’ of one octet representing the failure in performance of the operation (FAIL), and a value of at least one octet for representing more detailed information on the failure in performance of the operation may be additionally set in the return code field. 
       FIG. 19  is a signal flow chart for the control of a wireless high-frequency signal path forming device according to an embodiment of the present invention, in  FIG. 19 , the primary device may correspond to MCU, etc. of the base station main body system, and the secondary device is the path forming device in accordance with the present invention. Referring to  FIG. 19 , in step  100 , an initial access operation between the primary and secondary devices is performed according to the AISG rules, and in step  110 , the primary device transmits, to the secondary device, a High-level Data-Link Control (HDLC) message for an HDLC command (Procedure ID) according to the AISG rules. Accordingly, the secondary device receives the HDLC message in step  112  and identifies whether the HDLC message corresponds to an Information Frame (I-Frame) format configured in advance for controlling the operation of the path forming device, in step  114 . When the HDLC message corresponds to the I-Frame format, the secondary device proceeds to step  120 , and when the HDLC message does not correspond to the I-Frame format, the secondary device proceeds to step  115  to perform other operations, namely, an operation of processing an Unnumbered Frame (U-Frame) used for system management or a Supervisory Frame (S-Frame) used for link control. That is, in an embodiment of the present invention, an instruction for controlling the operation of the path forming device is transmitted by using an I-frame carrying the user information and control information for the user information. 
     In step  120 , the secondary device checks whether the procedure of the currently input frame corresponds to a procedure of the path forming device (SOS) according to an embodiment of the present invention. When the procedure corresponds to the SOS procedure, the process proceeds to step  124 , and when the procedure does not correspond to the procedure of the path forming device, the process proceeds to step  122  to process unknown procedures. 
     In step  124 , the secondary device extracts a procedure ID. That is, as shown in  FIG. 16B , the Procedure ID value may be ‘0x70’ correspond to the “SOSSetSwitchReset” procedure, ‘0x71’ corresponding to the “SOSGetSwitchStatus” procedure, ‘0x72’ corresponding to the “SOSSetSwitchPort” procedure, or ‘0x73’ corresponding to the “SOSGetSwitchPort” procedure. 
     Hereinafter, in step  131 , the secondary device checks whether the procedure ID value which is checked in step  124  correspond to ‘0x70’. When the procedure ID value corresponds to ‘0x70’, an operation for setting the path of the path forming device to the initial state is performed according to the “SOSSetSwitchReset” procedure, in step  132 . 
     On the other hand, when the procedure ID value which is checked in step  130  does not correspond to ‘0x70’, the process proceeds to step  133  and checks whether the procedure ID value corresponds to ‘0x71’. When the procedure ID value corresponds to ‘0x71’, the process proceeds to step  134  to perform an operation of checking output ends for all input ends of the path forming device according to the “SOSGetSwitchStatus” procedure. 
     On the other hand, when the procedure ID value which is checked in step  133  does not correspond to ‘0x71’, the process proceeds to step  135  and checks whether the procedure ID value corresponds to ‘0x72’. When the procedure ID value corresponds to ‘0x72’, the process proceeds to step  136  to perform an operation of connecting the input end and output end designated in the primary device according to the “SOSSetSwitchPort” procedure. 
     On the other hand, when the procedure ID value which is checked in step  135  does not correspond to ‘0x72’, the process proceeds to step  137  and checks whether the procedure ID value corresponds to ‘0x73’. When the procedure ID value corresponds to ‘0x73’, the process proceeds to step  138  to perform an operation of displaying an output end connected to an input end inquiring to the primary device according to the “SOSGetSwitchPort” procedure. 
     On the other hand, when the procedure ID value which is checked in step  137  does not correspond to ‘0x73’, the process proceeds to step  139  to perform a corresponding operation according to the procedure ID value. 
     Through the above steps, the secondary device performs a processing operation on the command (frames) received from the primary device, and checks the processing state including the processing result, in step  140 . In the subsequent step  150 , the secondary device transmits, to the primary device, the HDLC response message notifying of the processing result and whether to perform the normal operation. 
     As described above, configurations and operations can be made for a wireless high-frequency signal path forming device and a method for controlling the same according to an embodiment of the present invention. On the other hand, the above descriptions of the present invention have been made with reference to detailed embodiments thereof, however various changes can be made without departing from the scope of the invention. For example, in the above description, it has been described with respect to a plurality of procedures, and various procedures may also be set. For example, a procedure may be set for performing an automatic route setting operation, and the operation may be to check the normal operating condition of each amplifier in the path forming device, and when there is an amplifier failure, to perform an operation of automatically changing the path by itself. To this end, the path forming device may perform operations of storing information such as amplitude values and phase values on each path, monitoring the values in real time, and automatically changing the path when trouble occurs. 
     In addition, in the above description, it has been described that the path forming is made in a direction to maintain the operation of the antenna array located at the center in the whole antenna structure, however, other examples of the present invention may be implemented to achieve the path forming in a direction to maintain the operation of the antenna array located on the edge in the whole antenna structure. 
     In addition, in the above description, the path forming device was configured to be connected to the plurality of amplifiers, however, a configuration for connecting the path forming device to any other communication device for providing a wireless high-frequency signal may also possible, and a structure of indirectly connecting to the amplifier through the other communication devices can be made. 
     In the above description, it has been described that a controller (CPU) and the like is provided within the path forming device, the controller may also be separately provided on the outside of the path forming device. 
     Further, in the above description, it has been described that the remote wireless device, such as the RRH is configured to be attached separately to the outside of the base station antenna, for example, at the front end. In addition, the base station antenna can be implemented such that the remote wireless device is mounted inside the base station antenna. 
     As described above, a method for forming a wireless high-frequency signal path according to the present invention may enable the base station antenna to maintain the quality of a mobile communication service most stably, and enable the device installed in the base station antenna to be more efficiently controlled. 
     In addition to that, various modifications and variations can be made without departing from the scope of the present disclosure, and the scope of the present disclosure shall not be determined by the above-described embodiments and has to be determined by the following claims and equivalents thereof.