CN1988568B - Detecting method for no-electric terminal of asymmetric digital users - Google Patents

Detecting method for no-electric terminal of asymmetric digital users Download PDF

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Publication number
CN1988568B
CN1988568B CN2005101116684A CN200510111668A CN1988568B CN 1988568 B CN1988568 B CN 1988568B CN 2005101116684 A CN2005101116684 A CN 2005101116684A CN 200510111668 A CN200510111668 A CN 200510111668A CN 1988568 B CN1988568 B CN 1988568B
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test
line
adsl
broadband
impedance characteristic
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CN1988568A (en
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姜先荣
张博
梁侃
金少舫
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Shanghai Xinguotai Information Communication Co., Ltd.
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XINTAI COMMUNICATION TECHNOLOGY Co Ltd SHANGHAI
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Abstract

The invention relates to a method for detecting ADSL. Its characters show as follows: it automatically grasp line by DSLAM or grasp line by plug cable through switch-remote test server, and it detects the AC impedance characteristics and the proximal capacitance characteristics to the mixed line through a broadband test module, and it judges whether there is ADSL terminals or not according to thecomparison between the leisure DeltP parameters of AC impedance characteristics and the model DeltP of free lines. The invention also relates to a equipment for detecting ADSL, its features is that: it is composed of a broadband testing server, a broadband test equipment, a multiplexer for central DSL's access, a subscriber line, a ADSL modem, a ADSL separator, a client phone.

Description

A kind of asymmetric digital subscriber line is not gone up the electric terminals detection method
Technical field
The present invention relates to a kind of asymmetric digital subscriber line (ADSL) and do not go up the electric terminals detection method, judge that whether the asymmetric digital subscriber line terminal that do not power on exists, can whether exist and detect the domestic asymmetric digital subscriber line that do not power on (ADSL) user terminal of promoting the use of at present (ADSL MODEM or ADSL separator), can help telecom operators to carry out the ADSL fault fast positioning, belong to communication technical field.
Background technology
Along with being on the increase of asymmetric digital subscriber line ADSL, the broadband fault is also in quick growth, there is the fault more than 60% to be user side in its broadband fault, wherein be to be linked into copper core broken string in the circuit of ADSL terminal before the user terminal and the outsourcing medium is intact greatly, the clamping head is connected loosening with terminal, the inner contact of clamping head is bad, for the user, be difficult to find, and for the line attendant of operator, be difficult to too find, must solve this type of fault with segmentation thread-changing elimination methods, so this class ADSL Breakdown Maintenance becomes the very problem of headache of operator.How to judge that the circuit broken string still is to be right after the ADSL user terminal, this is that fault is judged very important branch, if can detect the terminal of far-end exists, just illustrate that also trunk circuit does not break to user side, whether traditional voice service is to exist by the detection phone to judge whether circuit arrives user side, at present judge whether phone exists technology very ripe, but for last after the ADSL business, there is such individual line subscriber, be that user side does not have phone, normally only connect the ADSL terminal, whether have by judging phone that to judge whether circuit arrives user side unworkable.
The existence of ADSL user terminal has two kinds of situations, the MODEM terminal of an ADSL powers on, this type can judge to also have a kind of not powering on by the handshake that detects MODEM, and detection method of the present invention is the detection at the ADSL terminal that does not power on.
Summary of the invention
The purpose of this invention is to provide and a kind ofly judge that rapidly, accurately asymmetric digital subscriber line (ADSL) do not go up the electric terminals detection method.
For realizing above purpose, technical scheme of the present invention provides a kind of asymmetric digital subscriber line and does not go up the electric terminals detection method, it is characterized in that,
A: end office's testing server grabs line automatically by local side DSL couple in multiplexer or the distributing frame connector is grabbed line, the different length ceases to be busy that extracts some is right, each is connected broadband test device to side a and b, test near-end swinging cross direct-to-ground capacitance C, near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg and side a and b ac impedance characteristic intermediate parameters Δ P-Ab over the ground respectively, set up functional relation each other;
1) end of the test bus of broadband test device is connect simultaneously the side a and b of test line, other end ground connection, the Digital Multi-Meter Test module testing ceases to be busy by broadband test device is to the near-end swinging cross direct-to-ground capacitance C of side a and b;
2) two ends with the test bus of broadband test device connect side a and b respectively, choose ceases to be busy to the measuring point of AB end signal source end and, circuit side measuring point and, ac impedance measurement module testing ceases to be busy by broadband test device is to the near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg over the ground of side a and b, Δ P is the ratio of test point signal source end power and test point circuit side power, and computing formula is:
ΔP=10log(p 0/p 1) (dB)
P 0Be test point signal source end power, P 1Be test point circuit side power;
3) the ac impedance characteristic intermediate parameters Δ P-Ab between the right side a and b line of test ceases to be busy, configuration, computational methods are with 2);
4) set up functional relation Δ P-Ab=F (C, Δ P-Abg) by least-square fitting approach;
B: end office's testing server grabs line automatically by local side DSL couple in multiplexer or the distributing frame connector is grabbed line, extract actual test line, each is connected broadband test device to actual test line side a and b, Digital Multi-Meter Test module by broadband test device is carried out Digital Multi-Meter Test to actual test line, judge whether circuit has swinging cross, bump, the ground vapour fault, described swinging cross is meant that resistance is less than 2kohm between the AB end, the described electricity that bumps is meant the AB end, the AG end, friendship between the BG end, direct voltage any one greater than 5V, described ground vapour is meant the AG end, resistance is less than 2kohm between the BG end, if have, directly finish test, cue circuit has fault, otherwise carries out c pacing examination;
C: to actual test line by near-end swinging cross direct-to-ground capacitance C and near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg over the ground come the computation-free line to the time Δ P-Ab parameter:
1) the near-end swinging cross direct-to-ground capacitance C of the tested actual track of test, method is with 1 among the step a);
2) near-end swinging cross ac impedance characteristic intermediate parameters Δ the P '-Abg over the ground of the tested actual track of test, method is with 2 among the step a);
3) calculate ac impedance characteristic intermediate parameters Δ P '-Ab between the side a and b line by function Δ P-Ab=F (C, Δ P-Abg);
D: test the ac impedance characteristic intermediate parameters Δ P1-Ab between tested actual track side a and b line, method is with 3 among the step a.);
E: ac impedance characteristic intermediate parameters Δ P '-Ab compares between the ac impedance characteristic intermediate parameters Δ P-Ab between the side a and b line that ceases to be busy is right and the side a and b line of actual track, if difference is greater than 1dB, illustrate that not to be ceases to be busy right, difference by ac impedance characteristic intermediate parameters Δ P1-Ab and Δ P '-Ab has judged whether the ADSL terminal again, if greater than 1dB, then thinking, difference has the ADSL terminal; Otherwise there is not the ADSL terminal.
A kind of asymmetric digital subscriber line is not gone up the equipment that the electric terminals detection method is disposed, it is characterized in that, by the broadband test server that contains the ADSL Tester Beyond Line that do not power on, broadband test device, possesses the local side DSL couple in multiplexer of grabbing the line function automatically, subscriber's line, ADSL Modem, the ADSL separator, the user side phone is formed, the broadband test server is connected with local side DSL couple in multiplexer by broadband test device, local side DSL couple in multiplexer is connected with the ADSL separator, and the ADSL separator is connected with the user side phone with ADSL Modem respectively.
Described broadband test device is made up of control output module, ac impedance measurement module and Digital Multi-Meter Test module, and the control output module connects ac impedance measurement module and Digital Multi-Meter Test module respectively.
The present invention adopts end office's testing server to grab line automatically by DSLAM or the distributing frame connector is grabbed line, by broadband test module testing ac impedance characteristic and near-end swinging cross direct-to-ground capacitance characteristic, irrelevant with terminal, the ac impedance characteristic intermediate parameters Δ P that obtains by test and the Δ P model of dead pair compare, and judge whether to exist the ADSL terminal.
The present invention can pass through the near-end swinging cross, directly test parameter over the ground, the parameter of test is not influenced by the terminal that connects between the AB circuit can fully, only relevant with line characteristic, and the test of the ac impedance characteristic intermediate parameters between AB is not influenced by user side phone set terminal type, can accurately judge line end (user side) and whether connect ADSL service terminal (ADSL modem or ADSL separator or both combination), can accurately test dead pair or the dead pair machine of answering and be judged as and do not have the ADSL terminal.
Whether advantage of the present invention is rapid, accurate test subscriber to hold asymmetric digital subscriber line (ADSL) terminal that does not power on to exist.
Description of drawings
Fig. 1 is the ADSL terminal test system configuration schematic diagram that do not power on;
Fig. 2 is the broadband test device high-level schematic functional block diagram;
The flow chart that Fig. 3 detects for the ADSL terminal that do not power on;
Parameter access model between Fig. 4 measurement circuit AB-G;
Fig. 5 is an ac impedance characteristic intermediate parameters Δ P test circuit model;
Fig. 6 is a parameter access model between measurement circuit AB.
Embodiment
The invention will be further described below in conjunction with drawings and Examples.
Embodiment
As Fig. 1, shown in 2, be the ADSL terminal test system configuration schematic diagram that do not power on, the equipment that the electric terminals detection method that do not go up described a kind of asymmetric digital subscriber line is disposed is by the broadband test server 1 that contains the ADSL Tester Beyond Line that do not power on, broadband test device 2, possesses the local side DSL couple in multiplexer 3 of grabbing the line function automatically, subscriber's line 4, ADSL Modem 5, ADSL separator 6, user side phone 7 is formed, broadband test server 1 is connected with local side DSL couple in multiplexer 3 by broadband test device 2, local side DSL couple in multiplexer 3 is connected with ADSL separator 6 by subscriber's line 4, and ADSL separator 6 is connected with user side phone 7 with ADSL Modem 5 respectively.
Described broadband test device 2 is made up of control output module 8, ac impedance measurement module 9 and Digital Multi-Meter Test module 10, and control output module 8 connects ac impedance measurement module 9 and Digital Multi-Meter Test module 10 respectively.
These testing equipments all are the products that the applicant sold several years, here use as known conditions, broadband test device possesses test ac impedance characteristic and Digital Multi-Meter Test function, also need possess the continue function of (test AB-ground) of near-end swinging cross, end office's testing server runs on the software under the ordinary PC environment.
As shown in Figure 3, flow chart for the ADSL terminal detection that do not power on, highlight the ADSL terminal detection algorithm that do not power on that disposes in the broadband test server below, its major function is by broadband test module testing ac impedance characteristic and near-end swinging cross direct-to-ground capacitance characteristic (irrelevant with terminal), the ac impedance characteristic intermediate parameters Δ P that obtains by test and the Δ P model of dead pair compare, judge whether to exist the ADSL terminal, specifically be divided into for five steps:
A: end office's testing server 1 grabs line automatically by local side DSL couple in multiplexer 3 or the distributing frame connector is grabbed line, extract 25, the ceases to be busy of different length is right, be that what device end the circuit two ends are not taken over and (required cable of the same type, the similar cable of " copper core polyolefin insulating plastic-aluminum composite sheath city communication cable " YD/T 322-1996 definition for example), the number of lines can be greater than 25, for being used for later step 1-4 curve fit number of data points, it is many more to count, the curve fit degree is high more, it is fixed to come according to the distribution of various places cable length during practical operation, test near-end swinging cross direct-to-ground capacitance C respectively, near-end swinging cross AC impedance intermediate parameters Δ P-Abg over the ground and, and AB ac impedance characteristic intermediate parameters Δ P-Ab, set up functional relation each other;
1) end of the test bus of broadband test device 2 is connect simultaneously the side a and b of test line, other end ground connection, Digital Multi-Meter Test module 10 by broadband test device 2 is tested the near-end swinging cross direct-to-ground capacitance C of ceases to be busys to side a and b, as shown in Figure 4, this Fig. 4 has introduced the method that the near-end swinging cross is tested over the ground that how to realize, promptly realize that at the broadband test device end side a and b line access point directly connects, various parameters after the swinging cross of test side a and b line and between the ground wire, the cable outsourcing protectiveness that requires testing equipment power supply ground and test line is altogether;
2) two ends with the test bus of broadband test device 2 connect side a and b respectively, choose the measuring point 11 and 12 of ceases to be busy to side a and b signal source end, circuit side measuring point 13 and 14 is tested near-end swinging cross over the ground the ac impedance characteristic intermediate parameters Δ P-Abg of ceases to be busys to side a and b by the ac impedance measurement module 9 of broadband test device 2; The test access model is seen Fig. 4, and the test circuit model be Fig. 6, and Fig. 6 has introduced and tested various parameters and access model broadband test device between the side a and b line, and the cable outsourcing protectiveness that requires testing equipment and test line altogether.
Δ P is the ratio of test point 11,12 signal source end power and test point 13,14 circuit side power, and computing formula is:
ΔP=10log(p 0/p 1) (dB)
P 0Be test point 11,12 signal source end power, P 1Be test point 13,14 circuit side power;
3) the ac impedance characteristic intermediate parameters Δ P-Ab between the right side a and b line of test ceases to be busy, the test access model is seen Fig. 6, the test circuit model be Fig. 4, computational methods same 2);
4) set up functional relation Δ P-Ab=F (C, Δ P-Abg) by least-square fitting approach;
B: end office's testing server 1 grabs line automatically by local side DSL couple in multiplexer 3 or the distributing frame connector is grabbed line, extract actual test line, each is connected broadband test device 2 to actual test line side a and b, 10 pairs of actual test lines of Digital Multi-Meter Test module by broadband test device 2 carry out Digital Multi-Meter Test, judge whether circuit has swinging cross, bump, the ground vapour fault, described swinging cross is meant that resistance is less than 2kohm between the AB end, the described electricity that bumps is meant the AB end, the AG end, friendship between the BG end, direct voltage any one greater than 5V, described ground vapour is meant the AG end, resistance is less than 2kohm between the BG end, if have, directly finish test, cue circuit has fault, otherwise carries out c pacing examination;
C: to actual test line by near-end swinging cross direct-to-ground capacitance C and near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg over the ground come the computation-free line to the time Δ P-Ab parameter:
1) the near-end swinging cross direct-to-ground capacitance C of the tested actual track of test, method is with 1 of step a);
2) near-end swinging cross ac impedance characteristic intermediate parameters Δ the P '-Abg over the ground of the tested actual track of test, method is with 2 of step a);
3) calculate ac impedance characteristic intermediate parameters Δ P '-Ab between the side a and b line by function Δ P-Ab=F (C, Δ P-Abg);
D: test the ac impedance characteristic intermediate parameters Δ P1-Ab between tested actual track side a and b line, method is with 3 of step a);
E: ac impedance characteristic intermediate parameters Δ P '-Ab compares between the ac impedance characteristic intermediate parameters Δ P1-Ab between the side a and b line that ceases to be busy is right and the side a and b line of actual track, if difference is greater than 1dB, illustrate that not to be ceases to be busy right, difference by ac impedance characteristic intermediate parameters Δ P1-Ab and Δ P '-Ab has judged whether the ADSL terminal again, if greater than 1dB, then thinking, difference has the ADSL terminal; Otherwise there is not the ADSL terminal.

Claims (3)

1. an asymmetric digital subscriber line is not gone up the electric terminals detection method, it is characterized in that,
A: end office's testing server (1) grabs line automatically by local side DSL couple in multiplexer (3) or the distributing frame connector is grabbed line, the different length ceases to be busy that extracts some is right, each is connected broadband test device (2) to side a and b, test near-end swinging cross direct-to-ground capacitance C, near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg and side a and b ac impedance characteristic intermediate parameters Δ P-Ab over the ground respectively, set up functional relation each other;
1) end of the test bus of broadband test device (2) is connect simultaneously the side a and b of test line, other end ground connection, Digital Multi-Meter Test module (10) the test ceases to be busy by broadband test device (2) is to the near-end swinging cross direct-to-ground capacitance C of side a and b;
2) two ends with the test bus of broadband test device (2) connect side a and b respectively, choose the measuring point (11,12) of ceases to be busy to AB end signal source end, circuit side measuring point (13,14), test near-end swinging cross over the ground the ac impedance characteristic intermediate parameters Δ P-Abg of ceases to be busy by the ac impedance measurement module (9) of broadband test device (2) to side a and b, Δ P is the ratio of test point (11,12) signal source end power and test point (13,14) circuit side power, and computing formula is:
ΔP=10log(p 0/p 1) (dB)
P 0Be test point (11,12) signal source end power, P 1Be test point (13,14) circuit side power;
3) the ac impedance characteristic intermediate parameters Δ P-Ab between the right side a and b line of test ceases to be busy, configuration, computational methods are with 2);
4) set up functional relation Δ P-Ab=F (C, Δ P-Abg) by least-square fitting approach;
B: end office's testing server (1) grabs line automatically by local side DSL couple in multiplexer (3) or the distributing frame connector is grabbed line, extract actual test line, each is connected broadband test device (2) to actual test line side a and b, Digital Multi-Meter Test module (10) by broadband test device (2) is carried out Digital Multi-Meter Test to actual test line, judge whether circuit has swinging cross, bump, the ground vapour fault, described swinging cross is meant that resistance is less than 2kohm between the AB end, the described electricity that bumps is meant the AB end, the AG end, friendship between the BG end, direct voltage any one greater than 5V, described ground vapour is meant the AG end, resistance is less than 2kohm between the BG end, if have, directly finish test, cue circuit has fault, otherwise carries out c pacing examination;
C: to actual test line by near-end swinging cross direct-to-ground capacitance C and near-end swinging cross ac impedance characteristic intermediate parameters Δ P-Abg over the ground come the computation-free line to the time Δ P-Ab parameter:
1) the near-end swinging cross direct-to-ground capacitance C of the tested actual track of test, method is with 1 among the step a);
2) near-end swinging cross ac impedance characteristic intermediate parameters Δ the P '-Abg over the ground of the tested actual track of test, method is with 2 among the step a);
3) calculate ac impedance characteristic intermediate parameters Δ P '-Ab between the side a and b line by function Δ P-Ab=F (C, Δ P-Abg);
D: test the ac impedance characteristic intermediate parameters Δ P1-Ab between tested actual track side a and b line, method is with 3 among the step a);
E: ac impedance characteristic intermediate parameters Δ P '-Ab compares between the ac impedance characteristic intermediate parameters Δ P-Ab between the side a and b line that ceases to be busy is right and the side a and b line of actual track, if difference is greater than 1dB, illustrate that not to be ceases to be busy right, difference by ac impedance characteristic intermediate parameters Δ P1-Ab and Δ P '-Ab has judged whether the ADSL terminal again, if difference is greater than 1dB, then think to have the ADSL terminal, otherwise do not have the ADSL terminal.
2. a kind of asymmetric digital subscriber line according to claim 1 is not gone up the equipment that the electric terminals detection method is disposed, it is characterized in that, by the broadband test server (1) that contains the ADSL Tester Beyond Line that do not power on, broadband test device (2), possesses the local side DSL couple in multiplexer (3) of grabbing the line function automatically, subscriber's line (4), ADSL Modem (5), ADSL separator (6), user side phone (7) is formed, broadband test server (1) is connected with local side DSL couple in multiplexer (3) by broadband test device (2), local side DSL couple in multiplexer (3) is connected with ADSL separator (6) by subscriber's line (4), and ADSL separator (6) is connected with user side phone (7) with ADSL Modem (5) respectively.
3. a kind of asymmetric digital subscriber line according to claim 2 is not gone up the equipment that the electric terminals detection method is disposed, it is characterized in that, described broadband test device (2) is made up of control output module (8), ac impedance measurement module (9) and Digital Multi-Meter Test module (10), and control output module (8) connects ac impedance measurement module (9) and Digital Multi-Meter Test module (10) respectively.
CN2005101116684A 2005-12-20 2005-12-20 Detecting method for no-electric terminal of asymmetric digital users Active CN1988568B (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2530409Y (en) * 2002-02-01 2003-01-08 淄博信通电器有限公司 ADSL line tester
CN2631133Y (en) * 2003-06-27 2004-08-04 上海欣泰通信技术有限公司 ADSL accessing comprehensive testing apparatus
CN1549467A (en) * 2003-05-10 2004-11-24 华为技术有限公司 Testing apparatus and method for XDSL

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2530409Y (en) * 2002-02-01 2003-01-08 淄博信通电器有限公司 ADSL line tester
CN1549467A (en) * 2003-05-10 2004-11-24 华为技术有限公司 Testing apparatus and method for XDSL
CN2631133Y (en) * 2003-06-27 2004-08-04 上海欣泰通信技术有限公司 ADSL accessing comprehensive testing apparatus

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CN 2530409 Y,全文.
JP特开2002-77389A 2002.03.15

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