CN102143279B - Detecting device, method and system - Google Patents
Detecting device, method and system Download PDFInfo
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- CN102143279B CN102143279B CN201010614406.0A CN201010614406A CN102143279B CN 102143279 B CN102143279 B CN 102143279B CN 201010614406 A CN201010614406 A CN 201010614406A CN 102143279 B CN102143279 B CN 102143279B
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Abstract
The invention discloses a detecting device, method and system, which belong to the technical field of communication. The device comprises a control module, a sampling resistor network and a controllable short-circuit loop, wherein one end of the controllable short-circuit loop is connected with a feedback loop of the sampling resistor network while the other end thereof is connected with the control module; one end of the sampling resistor network is connected with the control module while the other end thereof is connected with a test load; the sampling resistor network is used for sampling a test signal emitted from the control module and sending the sampled signal back to the control module; the controllable short-circuit loop is used for shorting out the feedback loop in the sampling resistor network; and the control module is used for shorting out the feedback loop in the sampling resistor network through controlling the controllable short-circuit loop so as to test the resistance-capacitance of the test load. The embodiment of the invention effectively reduces the interference error among lines in the sampling resistor network through controlling the working state of the controllable short-circuit loop so as to obtain more accurate testing result.
Description
Technical field
The present invention relates to communication technical field, particularly a kind of checkout equipment, method and system.
Background technology
Along with the continuous expansion of broadband network, operator requires towards the future development simple, maintainability is good, cost is low the O&M of broadband network.Wherein, concerning Virtual network operator, how can detect the telephone line of user side simply and effectively, to obtain its parameter needed, (this parameter can for direct voltage, insulation resistance, capacitance-resistance parameter etc., for telecommunications attendant provides basic line upkeep data), be need the eager problem solved.
In prior art, operator adopts the broadband network parameter of MELT (Metallic Line Test) testing equipment to user side to test.This testing equipment is arranged at place of operator, and operator can by the simple and effective parameter measuring needs of this equipment.As shown in Figure 1, at CO (Central Office, telephone exchange) side arranges MELT testing equipment, wherein, MELT substantial periphery circuit, this circuit comprises MELT module and sampling resistor network, and MELT module is by the load of sampling resistor network connecting test, and wherein test load comprises subscribers feeder and ustomer premises access equipment.Wherein, the concrete grammar being carried out parameter testing by this testing equipment is: the different parameters that MELT module is tested as required sends a low-frequency high-voltage test signal, this low-frequency high-voltage test signal is by cabling 2,3 and be sent to test load through sampling resistor, meanwhile, this low-frequency high-voltage signal lead 1,4 send MELT module back to by sampling resistor network.MELT module carries out calculation of parameter according to the amplitude of the signal received and phase information, obtains the capacitance-resistance value of test load, and the capacitance-resistance value of operator by obtaining, judges the O&M situation of test load.
After prior art is analyzed, inventor finds that prior art at least has following shortcoming: existing MELT checkout equipment is the capacitance-resistance value between unified test subscriber's line, wherein subscribers feeder is also known as AB line, it is the name of twisted pair telephone 2 lines, if A line capacitance-resistance value over the ground therefore will be obtained respectively, or B line capacitance-resistance value over the ground, need to carry out complicated de-embedding to test result in software, but in MELT peripheral circuit as shown in Figure 1, sampling resistor internetwork line holding wire close together, coupling capacitance meeting effect string drive test test result between line, especially the capacitance-resistance of line characteristic can be caused to test inaccurate, in de-embedding process, repeatedly use coarse test result can cause serious error accumulation, cause the test result precision finally obtained not high.
Summary of the invention
In order to the measuring accuracy improving broadband network embodiments provides a kind of checkout equipment, method and system.Described technical scheme is as follows:
On the one hand, provide a kind of checkout equipment, described equipment comprises: control module, sampling resistor network, controlled short-circuit loop;
One end of described controlled short-circuit loop is connected with the feedback loop of described sampling resistor network, and the other end is connected with described control module, and described sampling resistor network one end connects described control module, and the other end is connected with test load;
Described control module is used for by controlling described controlled short-circuit loop, makes the feedback loop of described sampling resistor network be in short-circuit condition, tests the capacitance-resistance value of described test load;
The test signal that described sampling resistor network sends for described control module of sampling, and send sampled signal back to described control module;
Described controlled short-circuit loop is in short-circuit condition for making the feedback loop in described sampling resistor network.
On the other hand, provide a kind of detection method, described method comprises:
Control any one group of controlled short-circuit loop and be in conducting state;
Send low-frequency high-voltage test signal and be sent to test load by sampling network;
Receive the feedback signal that described test load is sent back to by described sampling resistor network;
The capacitance-resistance value of described test load is calculated according to described feedback signal.
On the other hand, additionally provide a kind of detection system, described system comprises: checkout equipment, test load;
Wherein, described checkout equipment comprises: control module, sampling resistor network, controlled short-circuit loop;
One end of described controlled short-circuit loop is connected with the feedback loop of described sampling resistor network, and the other end is connected with described control module, and described sampling resistor network one end connects described control module, and the other end is connected with described test load;
The test signal that described sampling resistor network sends for described control module of sampling, and send sampled signal back to described control module;
Described controlled short-circuit loop is in short-circuit condition for making the feedback loop in described sampling resistor network;
Described control module is used for by controlling described controlled short-circuit loop, makes the feedback loop of described sampling resistor network be in short-circuit condition, tests the capacitance-resistance value of described test load.
The beneficial effect of the technical scheme that the embodiment of the present invention provides is: by controlling the operating state of controlled short-circuit loop, effectively reduces the mushing error between sampling resistor network center line, to obtain more accurate test result.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the circuit diagram of checkout equipment in prior art;
Fig. 2 is the structural representation of a kind of checkout equipment that the embodiment of the present invention 1 provides;
Fig. 3 is the circuit diagram of a kind of checkout equipment that the embodiment of the present invention 1 provides;
Fig. 4 is the flow chart of a kind of detection method that the embodiment of the present invention 2 provides;
Fig. 5 is the structural representation of a kind of detection system that the embodiment of the present invention 3 provides.
Embodiment
For making the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, embodiment of the present invention is described further in detail.
Embodiment 1
Participate in Fig. 2, present embodiments provide a kind of checkout equipment, on the basis of existing checkout equipment, increase controlled short-circuit loop, comprising: control module 101, sampling resistor network 102, controlled short-circuit loop 103;
One end of controlled short-circuit loop 103 is connected with the feedback loop of sampling resistor network 102, and the other end is connected with control module 101, sampling resistor network 102 one end link control module 101, and the other end is connected with test load;
Control module 101, for by controlling controlled short-circuit loop, makes the feedback loop of sampling resistor network 102 be in short-circuit condition, the capacitance-resistance value of test test load;
The test signal that sampling resistor network 102 sends for sampling control module, and send sampled signal back to control module;
Controlled short-circuit loop 103 is in short-circuit condition for making the feedback loop in sampling resistor network 102.
In the present embodiment, equal controlled short-circuit loop in parallel on each the group feedback loop in sampling resistor network 102, one end of controlled short-circuit loop connects the feedback loop of sampling resistor network, other end link control module.
Further, in the present embodiment, controlled short-circuit loop in parallel on any one group of feedback loop in sampling resistor network 102, one end of controlled short-circuit loop connects the feedback loop of sampling resistor network, other end link control module.
In the present embodiment, control module comprises gate-controlled switch, and gate-controlled switch one end connects controlled short-circuit loop, and control module makes controlled short-circuit loop be in conducting state by controlling the closed of gate-controlled switch.
Equipment in the present embodiment is applied to broadband line test, by the voltage cable to CPE (Customer PremiseEquipment, user side equipment) side, resistance, the test such as electric capacity judges line conditions, for telecommunications attendant provides basic line upkeep data.Such as, when certain network user application carries out broadband access network by home phone line, after Virtual network operator receives the application of user, need first to detect the telephone line of this user, obtain some parameters on this circuit, judge whether this circuit can meet the O&M requirement of broadband network for it, if obtain the requirement that test result meets operator, then also give this user installation broadband network, after user opens broadband network, operator also can the checkout equipment provided by the present embodiment frequently, detect some basic parameters of user side broadband line, for telecommunications attendant provides basic line upkeep data, attendant is made to grasp the operation situation of circuit.
See Fig. 3, be the circuit of the checkout equipment that the present embodiment provides, comprise: Melt module 10 (control module), sampling resistor network 18, short-circuit loop 16,17, controlled short-circuit end 13,15, gate-controlled switch 14,19.Wherein, Melt module 10 sends signal end and is connected to sampling resistor network 18 by cabling 20 and 24, sampling resistor network 18 is connected to load equipment 30 by cabling 31, wherein, load equipment 30 is CPE, 22 and 26 receive the signal fed back, sampling resistor network 18 also connects back the receiving terminal of Melt module 10 by sampling resistor network cabling (22 or 26), 31 is XDSL (Digital Subscribe Line, digital subscriber line) cable, be generally category 5 twisted pair, signal on circuit is connected to the controlled short-circuit end 13 and 15 of Melt module simultaneously through short-circuit loop 16 and 17, its center line 31 and load equipment 30 are test load.Further, control corresponding software Closing Switch 14 or 19 by Melt module 10, switch 14 and 19 completes fault control by short circuit loop 16 and 17.Gate-controlled switch 14 and 19 is placed in chip internal.45 represent MELT module and DSL business module directly has annexation.Short-circuit loop, controlled short-circuit end, gate-controlled switch form controlled short-circuit loop.
The beneficial effect of the technical scheme that the embodiment of the present invention provides is: by controlling the operating state of controlled short-circuit loop, parameter testing between AB line is fully separated, effectively reduce the mushing error between line, and by the short-circuit calibration value that prestores, test value is verified, thus obtains more accurate test result.
Embodiment 3
See Fig. 4, present embodiments provide a kind of detection method, comprising:
Step 201: send low-frequency high-voltage test signal and be sent to test load by sampling resistor network;
Step 202: receive the feedback signal that test load is sent back to by sampling resistor network;
Step 203: the capacitance-resistance value calculating test load according to feedback signal.
Wherein, transmission low-frequency high-voltage test signal also comprises before being sent to described test load by sampling resistor network:
Acquisition prestores short-circuit calibration value.
Correspondingly, in the present embodiment, calculate the capacitance-resistance value of test load according to feedback signal, also comprise afterwards:
Judge whether the capacitance-resistance value obtained meets pre-conditioned;
If met, then show that this test does not exist error, using the capacitance-resistance value that obtains as described check test value; If do not met, then show that this test exists error, the capacitance-resistance value obtained and the short-circuit calibration value that prestores are carried out read group total, obtains check test value.
In the present embodiment, being convenient to make those skilled in the art understand the present invention, carrying out capacitance-resistance test to utilize the testing circuit shown in Fig. 3 and being described.
Wherein, before carrying out capacitance-resistance test, preferably, by arranging short circuit condition, preserve one group of capacitance-resistance check value in advance, namely prestore short-circuit calibration value.Concrete, control gate-controlled switch and close, by the line short circuit of Melt module 10 to ground, test loop now, the test value obtained is the short-circuit calibration value that prestores.In the present embodiment, in order to ensure the accuracy of data, before each parameter testing, can all obtain the short-circuit calibration value that once prestores, also can obtain the short-circuit calibration value that once prestores within the time of presetting, the present embodiment is not specifically limited at this.
In the present embodiment, controlled short-circuit loop has three kinds of selective operational modes, can guarantee that measurement circuit capacitance-resistance parameter is more accurate, and pattern one: 19 disconnects, and 14 close, separately test A line; Pattern two: 14 disconnects, and 19 close, independent test b line; Pattern three is 14 and 19 to disconnect simultaneously, parameter between test A, B line and AB line.In the present embodiment, the demand different according to client, by controlling the operating state of short-circuit loop, ensures the independence of single line test, thus improves measuring accuracy.As, when needing to test A parameter over the ground, the controlled short-circuit loop at control B line place is in short-circuit condition, when Melt module 10 starts to test, send a low-frequency high-voltage test signal by cabling 22,24 and be sent to test load 30 through sampling resistor, but because the feedback loop at now B line place is in short-circuit condition, so Melt module 10 only receives the signal that test load feeds back by 26 at A line place, Melt module 10 calculates the signal fed back, obtain A line parameter over the ground, which reduces 22,20 to 24,26 line between disturb.Equally when needing test b parameter over the ground, the controlled short-circuit loop at control A line place is in short-circuit condition, when Melt module 10 starts to test, send a low-frequency high-voltage test signal by cabling 22,24 and be sent to test load 30 through sampling resistor, but because the feedback loop at now A line place is in short-circuit condition, so Melt module 10 only receives the signal fed back by 20, Melt module 10 calculates the signal fed back, obtain B line parameter over the ground, which reduces 24,26 to 22,20 line between disturb.
After obtaining test parameter, Melt module 10 is according to after the low-frequency high-voltage signal received, obtain amplitude and the phase place of this signal, the concrete amplitude according to low-frequency high-voltage signal and phase information carry out calculation of parameter, and test obtains one group of capacitance-resistance test value A of test load.Wherein, after obtaining test value A, test value A is assessed, judge whether the capacitance-resistance value A obtained meets pre-conditioned, if met, then this test value A is directly exported as calibration testing value; If do not met, carrying out read group total to test value A and the short-circuit calibration value that prestores, obtain calibration testing value C.After obtaining calibration testing value C, test value C will be calibrated and export.Wherein, the condition preset shows that test value exists the pre-conditioned of error, judged by formula (1):
2pi*freq*Ctest*Rtest < D formula (1)
Wherein, Pi is circumference ratio, Freq: be the frequency test signal that MELT module sends, Ctest: be the capacitance in capacitance-resistance test value A, Rtest: be the resistance value in capacitance-resistance test value A, D: for can a constant of self-defining, and this present embodiment is set to 0.1.If the value obtained after wherein the resistance value in the capacitance-resistance value obtained and capacitance being substituted into formula (1) is respectively less than D (0.1), then this capacitance-resistance value meets pre-conditioned, this test value of surface does not have error, if the value obtained after the resistance value in the capacitance-resistance value obtained and capacitance are substituted into formula (1) is respectively greater than D, then this capacitance-resistance value does not meet pre-conditioned, shows that this test exists error.
In the present embodiment, the testing circuit in Application Example 1 tests the parameter value such as voltage cable, resistance, electric capacity of cpe side in broadband line network, for telecommunications attendant provides basic line upkeep data.
The beneficial effect of the technical scheme that the embodiment of the present invention provides is: by controlling the operating state of controlled short-circuit loop, effectively reduce the mushing error between sampling resistor network center line, and by the short-circuit calibration value that prestores, test value is verified, thus obtain more accurate test result.
Embodiment 3
See Fig. 5, embodiments provide a kind of detection system, the detection system in the present embodiment is in the wireline inspection in broadband network, comprising: checkout equipment 301 and test load 302.
Wherein, checkout equipment 302 comprises: control module, sampling resistor network, controlled short-circuit loop;
One end of controlled short-circuit loop is connected with the feedback loop of sampling resistor network, and the other end is connected with control module, sampling resistor network one end link control module, and the other end is connected with test load 302;
Sampling resistor network is used for the test signal that sampling control module sends, and sends sampled signal back to control module;
Controlled short-circuit loop is in short-circuit condition for making the feedback loop in sampling resistor network;
Control module is used for by controlling controlled short-circuit loop, makes the feedback loop of sampling resistor network be in short-circuit condition, the capacitance-resistance value of test test load 302.
In the present embodiment, equal controlled short-circuit loop in parallel on each the group feedback loop in sampling resistor network, one end of controlled short-circuit loop connects the feedback loop of sampling resistor network, other end link control module.
Further, in the present embodiment, controlled short-circuit loop in parallel on any one group of feedback loop in sampling resistor network, one end of controlled short-circuit loop connects the feedback loop of sampling resistor network, other end link control module.
Preferably, in the present embodiment, control module comprises gate-controlled switch, and gate-controlled switch one end connects controlled short-circuit loop, and control module makes controlled short-circuit loop be in conducting state by controlling the closed of gate-controlled switch.
The beneficial effect of the technical scheme that the embodiment of the present invention provides is: by controlling the operating state of controlled short-circuit loop, effectively reduce the mushing error between sampling resistor network center line, and by the short-circuit calibration value that prestores, test value is verified, thus obtain more accurate test result.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (9)
1. a detection method, is characterized in that, described method comprises:
Acquisition prestores short-circuit calibration value;
Control any one group of controlled short-circuit loop and be in conducting state;
Send low-frequency high-voltage test signal and be sent to test load by sampling resistor network;
Receive the feedback signal that described test load is sent back to by described sampling resistor network;
The capacitance-resistance value of described test load is calculated according to described feedback signal;
Judge whether the described capacitance-resistance value obtained meets pre-conditioned; Wherein, describedly pre-conditionedly refer to 2pi*freq*Ctest*Rtest<D, pi is circumference ratio, freq is the frequency of described low-frequency high-voltage test signal, Ctest is the capacitance in described capacitance-resistance value, and Rtest is the resistance value in described capacitance-resistance value, and D is predetermined threshold value;
If met, then show that this test does not exist error, using the described capacitance-resistance value that obtains as check test value; If do not met, then show that this test exists error, the described capacitance-resistance value obtained and the described short-circuit calibration value that prestores are carried out read group total, obtains described check test value.
2. a checkout equipment, is characterized in that, described equipment comprises: control module, sampling resistor network, controlled short-circuit loop;
One end of described controlled short-circuit loop is connected with the feedback loop of described sampling resistor network, and the other end is connected with described control module, and described sampling resistor network one end connects described control module, and the other end is connected with test load;
The test signal that described sampling resistor network sends for described control module of sampling, and send sampled signal back to described control module;
Described controlled short-circuit loop is in short-circuit condition for making the feedback loop in described sampling resistor network;
Described control module is used for by controlling described controlled short-circuit loop, makes the feedback loop of described sampling resistor network be in short-circuit condition, tests the capacitance-resistance value of described test load;
Described control module, also for performing detection method as described in claim 1.
3. equipment according to claim 2, it is characterized in that, equal controlled short-circuit loop in parallel on each group feedback loop in described sampling resistor network, one end of described controlled short-circuit loop connects the feedback loop of described sampling resistor network, and the other end connects described control module.
4. equipment according to claim 2, it is characterized in that, controlled short-circuit loop in parallel on any one group of feedback loop in described sampling resistor network, one end of described controlled short-circuit loop connects the feedback loop of described sampling resistor network, and the other end connects described control module.
5. checkout equipment according to claim 2, it is characterized in that, described control module comprises gate-controlled switch, and described gate-controlled switch one end connects described controlled short-circuit loop, and described control module makes described controlled short-circuit loop be in conducting state by controlling the closed of described gate-controlled switch.
6. a detection system, is characterized in that, described system comprises: checkout equipment, test load;
Wherein, described checkout equipment comprises: control module, sampling resistor network, controlled short-circuit loop;
One end of described controlled short-circuit loop is connected with the feedback loop of described sampling resistor network, and the other end is connected with described control module, and described sampling resistor network one end connects described control module, and the other end is connected with described test load;
The test signal that described sampling resistor network sends for described control module of sampling, and send sampled signal back to described control module;
Described controlled short-circuit loop is in short-circuit condition for making the feedback loop in described sampling resistor network;
Described control module is used for by controlling described controlled short-circuit loop, makes the feedback loop of described sampling resistor network be in short-circuit condition, tests the capacitance-resistance value of described test load;
Described control module, also for performing detection method as described in claim 1.
7. system according to claim 6, it is characterized in that, equal controlled short-circuit loop in parallel on each group feedback loop in described sampling resistor network, one end of described controlled short-circuit loop connects the feedback loop of described sampling resistor network, and the other end connects described control module.
8. system according to claim 6, it is characterized in that, controlled short-circuit loop in parallel on any one group of feedback loop in described sampling resistor network, one end of described controlled short-circuit loop connects the feedback loop of described sampling resistor network, and the other end connects described control module.
9. detection system according to claim 6, it is characterized in that, described control module comprises gate-controlled switch, and described gate-controlled switch one end connects described controlled short-circuit loop, and described control module makes described controlled short-circuit loop be in conducting state by controlling the closed of described gate-controlled switch.
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| CN201010614406.0A CN102143279B (en) | 2010-12-28 | 2010-12-28 | Detecting device, method and system |
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| CN201010614406.0A CN102143279B (en) | 2010-12-28 | 2010-12-28 | Detecting device, method and system |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1311597A (en) * | 2000-05-17 | 2001-09-05 | 深圳市中兴通讯股份有限公司 | Test device and method for telephone line |
| CN101014063A (en) * | 2007-02-15 | 2007-08-08 | 华为技术有限公司 | Method and apparatus for measuring line capacity |
| CN101217594A (en) * | 2008-01-14 | 2008-07-09 | 中兴通讯股份有限公司 | A test method of insulation resistance and capacitance on telephone lines |
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2010
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1311597A (en) * | 2000-05-17 | 2001-09-05 | 深圳市中兴通讯股份有限公司 | Test device and method for telephone line |
| CN101014063A (en) * | 2007-02-15 | 2007-08-08 | 华为技术有限公司 | Method and apparatus for measuring line capacity |
| CN101217594A (en) * | 2008-01-14 | 2008-07-09 | 中兴通讯股份有限公司 | A test method of insulation resistance and capacitance on telephone lines |
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