Abstract:
A device for testing a function of a telephone exchange during a production process includes a sending-end module for sending a test criterion, a receiving-end module for receiving a test criterion, an input/output interface module connected to a telephone exchange, a call connection indicating unit, a signal switching unit, and a controlling unit for controlling a test procedure. The device not only tests whether a call can be connected and whether a call can be answered, but analyzes local electrical characteristics of the telephone exchange at the telephone exchange-end. With the device, signals treated by an analog-to-digital conversion process can display various voice information of a voice signal conveyed by the telephone exchange, such that a damaged portion of the telephone exchange can be assessed whenever a test fails, thereby cutting test costs and production costs.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s).100111543 filed in Taiwan, R.O.C. on Apr. 1, 2011, the entire contents of which are hereby incorporated by reference. 
       FIELD OF TECHNOLOGY 
       [0002]    The present invention relates to automatic test devices, and more particularly, to a device for testing a call connection function of a telephone exchange during a production process. 
       BACKGROUND 
       [0003]    A call connection function test has to be conducted during a manufacturing process of some telecommunication products which include a conventional telephone exchange, an online telephone exchange, and even an optical network terminal (ONT), a cable modem, and a DSL modem which have an online telephone exchange function. 
         [0004]    In this regard, a conventional test entails: connecting two telephone set interfaces of a telephone exchange to two telephone sets, respectively; calling first said telephone set from second said telephone set manually; and determining a call connection function of the telephone exchange according to whether first said telephone set rings or not and whether the call can be answered. However, the conventional test is predisposed to mistakes of manual operation and human-induced errors in criteria of judgment. 
         [0005]    Another conventional test entails: connecting two modems which are connected to a computer to two telephone set interfaces of the telephone exchange, respectively; and determining a call connection function of the telephone exchange by the computer controlling the modems in outputting and receiving a signal. However, to effectuate collaborative operation, the conventional test requires two additional modems which occupy much space on a production line, make it impossible to perform a test on plenty of products simultaneously, and fail to obtain sufficient test data. 
         [0006]    Yet another conventional test entails obtaining a complete test result by a precise apparatus. Although the test result thus obtained is relatively complete, the precise apparatus is expensive and thus only applicable to a test conducted in a R&amp;D stage or a design stage rather than a test conducted on a production line. 
       SUMMARY 
       [0007]    It is an objective of the present invention to provide a device that meets the need to perform a test on a production line quickly and accurately. 
         [0008]    Another objective of the present invention is to provide a device that can be automatically operated such that a plurality of telephone exchanges can be tested by the devices concurrently. 
         [0009]    Yet another objective of the present invention is to provide a device for providing a call connection function, evaluating local electrical characteristics, and testing the quality of a voice signal. 
         [0010]    In order to achieve the above and other objectives, the present invention provides a device for testing a function of a telephone exchange. The device comprises: a sending-end module for generating and sending a voice signal and a dialing signal to the telephone exchange; a receiving-end module for testing electrical characteristics of the voice signal sent from the telephone exchange after being transmitted inside the telephone exchange, and for converting the voice signal sent from the telephone exchange into a digital signal; an input/output interface module comprising a telephone set interface unit and comprising a first interface and a second interface which are electrically connected to two telephone set interfaces of the telephone exchange, respectively; a call connection indicating unit electrically connected to the telephone set interface unit for generating an indicating signal in response to a status of electrical connection between the first interface and the second interface; a signal switching unit electrically connected to the sending-end module, the receiving-end module, and the telephone set interface unit and adapted to switch a transmission path of the voice signal; and a controlling unit electrically connected to the sending-end module, the receiving-end module, the call connection indicating unit, and the signal switching unit and adapted to controllably drive the sending-end module and the signal switching unit to send the dialing signal to the telephone exchange via the first interface. After receiving the dialing signal, the telephone exchange generates a ring signal. The ring signal enters the call connection indicating unit via the input/output interface module and produces a first test result according to whether the indicating signal has been generated. 
         [0011]    In an embodiment, under the control of the controlling unit, the signal switching unit receives a local voltage current signal from a telephone set interface of the telephone exchange through the second interface in response to generation of the indicating signal and sends the local voltage current signal to the receiving-end module such that electrical characteristics of the local voltage current signal are treated as a second test result. 
         [0012]    In an embodiment, under the control of the controlling unit, the sending-end module generates the voice signal, and the voice signal sent out from the telephone exchange and received via the second interface is sent to the receiving-end module through the signal switching unit, such that the voice signal converted into a digital signal by the receiving-end module is treated as a third test result. 
         [0013]    In an embodiment, the sending-end module further comprises: a dialing unit controlled by the controlling unit and adapted to generate the dialing signal for performing a dialing operation; and a voice generating unit controlled by the controlling unit and adapted to generate the voice signal. 
         [0014]    In an embodiment, the receiving-end module further comprises: a voice signal amplifying unit electrically connected to the signal switching unit and adapted to amplify the voice signal sent out from the telephone exchange; a current/voltage testing unit electrically connected to the signal switching unit and adapted to test a current/voltage level of the voice signal and a local current/voltage level of the local voltage current signal; and an analog-to-digital conversion unit electrically connected to the voice signal amplifying unit and the current/voltage testing unit and adapted to convert the voice signal thus amplified, the current/voltage level of the voice signal, and the local current/voltage level of the local voltage current signal into a digital signal and send the digital signal to the controlling unit. 
         [0015]    In an embodiment, the controlling unit compares the voice signal which has been converted into the digital signal and a preset audio standard data and treats a comparison result as the third test result. 
         [0016]    The device of the present invention not only tests whether a call can be connected and whether a call can be answered, but analyzes electrical characteristics of an interface of the telephone exchange. With the device, signals treated by an analog-to-digital conversion process can display various voice information of a voice signal conveyed by the telephone exchange, and all the test results are quantified and conveyed to a back-end computer, such that a damaged portion of the telephone exchange can be assessed at the manufacturer end whenever a test fails, thereby cutting test costs, testing time, and production costs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    Objectives, features, and advantages of the present invention are hereunder illustrated with specific embodiments in conjunction with the accompanying drawings, in which: 
           [0018]      FIG. 1  is a function block diagram of a device for testing a telephone exchange according to an embodiment of the present invention; and 
           [0019]      FIG. 2  is a function block diagram of a device for testing a telephone exchange according to another embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Referring to  FIG. 1 , there is shown a function block diagram of a device for testing a telephone exchange according to an embodiment of the present invention. The device comprises a sending-end module  110 , a receiving-end module  120 , an input/output interface module  130 , a call connection indicating unit  140 , a signal switching unit  150 , and a controlling unit  160 . 
         [0021]    The sending-end module  110  is controlled by the controlling unit  160  and is for use in generating a dialing signal and a voice signal. The dialing signal is for triggering a telephone exchange, that is, triggering a call connection function of a product under test, such that the telephone exchange is in a call-connected status. Afterward, the telephone exchange generates a call connection ring signal and sends the ring signal to the call connection indicating unit  140  via the input/output interface module  130 . The voice signal is for determining the quality of the voice transmission of the telephone exchange That is, after the voice signal has been delivered within the telephone exchange, it is feasible to determine whether the strength, the signal frequency shift, and the signal to noise level of the voice signal sent from the telephone exchange meet the related standards. With the device according to an embodiment of the present invention, the aforesaid are quantified and provided to a back-end computer  300  for determination. 
         [0022]    The receiving-end module  120  is for testing the electrical characteristics of the voice signal sent from the telephone exchange so as to determine the electrical characteristics of the voice signal sent from a local end of the telephone exchange, and is for amplifying the voice signal so as to determine the quality of the voice signal, such as the strength of the voice signal. The receiving-end module  120  also converts the determined electrical characteristics and the amplified voice signal into a digital signal, such that the digital signal drives the back-end computer  300  to record data. 
         [0023]    In an embodiment of the present invention, the device simulates a sending end and a receiving end, and thus the input/output interface module  130  comprises a first interface  132  as a first telephone set and a second interface  134  as a second telephone set. Hence, the interfaces  132 ,  134  can be electrically connected to the two telephone set interfaces of the telephone exchange, respectively. The input/output interface module  130  comprises a telephone set interface unit  136  which is electrically connected to the interfaces and used for serving as a bridge interface for signal transmission. 
         [0024]    The call connection indicating unit  140  is electrically connected to the telephone set interface unit  136  in response to whether the dialing signal generated by the sending-end module  110  has successfully triggered the telephone exchange. After receiving the dialing signal, the telephone exchange generates the ring signal. The ring signal enters the call connection indicating unit  140  via the input/output interface module  130 . The call connection indicating unit  140  converts the ring signal into an indicating signal. That is, the first interface  132  and the second interface  134  will be electrically connected, provided that the call connection function of the telephone exchange is good. Hence, the ring signal generated by the telephone exchange enables the call connection indicating unit  140 . For example, the indicating signal is equivalent to a ring at the receiving end. 
         [0025]    The signal switching unit  150  is controlled by the controlling unit  160  and is electrically connected to the sending-end module  110 , the receiving-end module  120 , and the telephone set interface unit  136  for switching a transmission path of the voice signal. That is, the signal switching unit  150  controlled by the controlling unit  160  distinguishes the test signal sending function from the test signal receiving function of the device, such that the transmission of signals can be correctly processed. 
         [0026]    The controlling unit  160  is the core of the control of the test procedure carried out by the device according to an embodiment of the present invention. The controlling unit  160  is electrically connected to the sending-end module  110 , the receiving-end module  120 , the call connection indicating unit  140 , and the signal switching unit  150 . Under the control of the controlling unit  160 , the sending-end module  110  sends the dialing signal to the telephone exchange through the first interface  132  of the input/output interface module  130  to produce a first test result according to whether the indicating signal has been generated. Under the control of the controlling unit  160 , the signal switching unit  150  receives the local voltage current signal from a telephone set interface of the telephone exchange through the second interface  134  in response to the generation of the indicating signal and sends the local voltage current signal to the receiving-end module  120  such that the electrical characteristics of the local voltage current signal are treated as a second test result. 
         [0027]    The controlling unit  160  can further control the sending-end module  110  in sending out the voice signal through the signal switching unit  150  which has undergone a switching process once again and the first interface  132  in response to the generation of the electrical characteristics of the voice signal. Afterward, the second interface  134  receives the voice signal from the telephone exchange. Then, the voice signal is sent to the receiving-end module  120  through the signal switching unit  150  which has undergone a switching process once again, converted into the digital signal, and treated as a third test result. 
         [0028]    Afterward, the test results are sent to the computer  300 . The controlling unit  160  treats the voice signal which has been amplified and converted into the digital signal as the third test result and sends it to the computer  300 . Alternatively, the controlling unit  160  compares the voice signal which has been amplified and converted into the digital signal and a preset audio standard data, treats the comparison result as the third test result, and sends the third test result to the computer  300 . 
         [0029]    Accordingly, the process flow of a test conducted by means of the device according to an embodiment of the present invention is described hereunder. 
         [0030]    Under the control of the controlling unit  160 , the sending-end module  110  generates the dialing signal for performing a dialing operation and sends the dialing signal thus generated to the telephone exchange. 
         [0031]    Once the telephone exchange successfully receives the dialing signal, that is, when the call gets connected, it will mean that the call connection function of the telephone exchange (i.e., the device under test) is good. As a result, the call connection indicating unit  140  receives the ring signal from the telephone exchange The call connection indicating unit  140  converts the ring signal into the indicating signal (a first test result) and informs the controlling unit  160  of the aforesaid signal conversion. Afterward, under the control of the controlling unit  160 , the receiving-end module  120  answers the call; or, in other words, under the control of the controlling unit  160 , the signal switching unit  150  causes the local voltage current signal to be transmitted from a telephone set interface of the telephone exchange to the receiving-end module  120 . 
         [0032]    The receiving-end module  120  processes the local voltage current signal to identify electrical characteristics (a second test result) thereof, digitalizes the electrical characteristics thus identified, and sends the second test result to an internal memory of the controlling unit  160  or an external memory (not shown). 
         [0033]    Then, under the control of the controlling unit  160 , the sending-end module  110  generates the voice signal to simulate the course of a call, and the voice signal is sent to an interface of the telephone exchange. Afterward, the telephone exchange sends out the voice signal via another interface; and then, under the control of the controlling unit  160 , the voice signal is sent to the receiving-end module  120  and processed therein to yield a third test result. 
         [0034]    Eventually, the first, second, and third test results are sent to the computer  300 . The test results are going to be analyzed by the computer  300  later. However, the controlling unit  160  can also perform the aforesaid analysis in part or even in whole. This embodiment is just illustrative of the present invention. Persons skilled in the art can readily conceive different aspects of the implementation of data analysis of the present invention without being limited by the disclosure of this embodiment. 
         [0035]    Referring to  FIG. 2 , there is shown a function block diagram of a device for testing the telephone exchange according to another embodiment of the present invention. The sending-end module  110  further comprises a dialing unit  112  and a voice generating unit  114 . The dialing unit  112  is electrically connected to the signal switching unit  150 . The dialing unit  112  is placed under the control of the controlling unit  160  and adapted to generate the dialing signal for performing a dialing operation. The voice generating unit  114  is electrically connected to the signal switching unit  150  and is also placed under the control of the controlling unit  160  to generate the voice signal. For example, an audio information can be stored in the voice generating unit  114  in advance, such that the stored audio information can be selected by the controlling unit  160  whenever the voice signal is to be generated. 
         [0036]    The receiving-end module  120  further comprises a voice signal amplifying unit  122 , a current/voltage testing unit  124 , and an analog-to-digital conversion unit  126 . The voice signal amplifying unit  122  is electrically connected to the signal switching unit  150  and adapted to amplify the voice signal. The current/voltage testing unit  124  is electrically connected to the signal switching unit  150  and adapted to measure the voice signal current/voltage level and a local current/voltage level at a telephone set interface of the telephone exchange, so as to obtain the local electrical characteristics of the telephone exchange. The analog-to-digital conversion unit  126  is electrically connected to the voice signal amplifying unit  122 , the current/voltage testing unit  124 , and the controlling unit  160  and adapted to convert the amplified voice signal and the current/voltage level of the voice signal into a digital signal for being transmitted to the controlling unit  160 . 
         [0037]    In conclusion, in an embodiment of the present invention, the device quantifies all the test items and sends the quantified data to the computer  300 . The test results indicate whether the test items are up to standard or not. Upon detection of a non-conforming telephone exchange, the manufacturer end of the non-conforming telephone exchange can determine, by making reference to the test results, whether the problem lies in an audio amplifying circuit, an audio encoding/decoding circuit, or an interface local current/voltage generating circuit of the non-conforming telephone exchange, so as to reduce the time taken to perform maintenance, thereby cutting test costs and production costs. 
         [0038]    The present invention is disclosed above by preferred embodiments. However, persons skilled in the art should understand that the preferred embodiments are illustrative of the present invention only, but should not be interpreted as restrictive of the scope of the present invention. Hence, all equivalent modifications and replacements made to the aforesaid embodiments should fall within the scope of the present invention. Accordingly, the legal protection for the present invention should be defined by the appended claims.