1. Foundation
The specifications hereunder is issued pursuant to paragraph 1 of Article 42 of the Telecommunications Acts.

2. Scope
The specifications apply only to the Asymmetric Digital Subscriber Line （ADSL）Terminal Equipment （ATU-R）and POTS Splitter.

3. Contents and Reference
3.1 This specification is established in reference to the ITU-T Rec. G.992.1、G.992.3、G.992.5 and G.996.1；and other international technical standards.
3.2 In consideration of consistency between this technical specification and the international technical standards, NCC will adhere to the pertinent modification as in the latest version of the technical standards in regard to test items, conformance requirement and test methods established in this specification.

4. Abbreviations

5. ADSL System Framework
This Recommendation defines the minimal set of requirements to provide satisfactory simultaneous transmission between the network and the customer interface of a variety of high-speed simplex and low-speed duplex channels and other services such as POTS. The system framework shown in follow Figure illustrates the functional blocks required to provide ADSL service.

6. Test Items and documents specified
6.1 POTS Splitter Test detailed list
6.2 ATU-R Test detailed list
6.3 ATU-R with POTS splitter function comply with requirements of 6.1 and 6.2.

7. POTS Splitter interface testing
7.1 DC Loop Resistance
7.1.1 Purpose：To verify that the POTS Splitter DC Loop Resistance is in compliance with the requirements specified in 6.1.
7.1.2 measurement arrangement：
7.1.3 Method of measurement：
（1）The measurement arrangement is given in Figure 1.
（2）The U-R interface shorted and to adjust the POTS loop currents to 10mA.
（3）To measurement DC voltage from tip-to-ring at the POTS interface.
（4）To calculate DC Loop Resistance.
（5）Repeat step (3),(4) for adjusting the POTS loop currents to 20mA.,60mA and 100mA.
（6）To calculate the DC Loop resistance from tip-to-ring at the POTS interface.
7.2 Insulation Resistance
7.2.1 Purpose：To verify that the POTS Splitter DC Insulation Resistance is in compliance with the requirements specified in 6.1.
7.2.2 measurement arrangement：
7.2.3 Method of measurement：
（1）The measurement arrangement is given in Figure 2.
（2）The U-R interface opened and to adjust the insulation resistance tester output voltage to DC100V。
（3）To measurement the insulation resistance from ring-to-ground at the POTS interface.
（4）To measurement the insulation resistance from tip-to-ground at the POTS interface.
（5）To measurement the insulation resistance from tip-to-ring at the POTS interface.
7.3 Insertion Loss in the Voice Band
7.3.1 Purpose：To verify that the POTS Splitter insertion loss in the voice band (1004Hz) is in compliance with the requirements specified in 6.1.
Simulate test loop ：0,0.5kft,2.0kft,5.0 kft pairs of 26 AWG Cable.
7.3.2 measurement arrangement：
7.3.3 Method of measurement：
（1）The measurement arrangement is given in Figure 4.
（2）To choose 26AWG 0ft Cable test loop, the insertion loss at 1004 Hz from the source to the termination shall be measured and without the POTS Splitter/ZHP-r combination inserted.
（3）the insertion loss at 1004 Hz from the source to the termination shall be measured and with the POST Splitter/ZHP-r combination inserted.
（4）To choose 26AWG 5kft Cable , ANSI Loop13, CSA Loop4, Loop8 test loop, repeat step (2),(3).
（5）To calculate insertion loss. and record test result
7.4 Attenuation in the ADSL Band
7.4.1 Purpose：To verify that the POTS Splitter attenuation in the ADSL band is in compliance with the requirements specified in 6.1.
7.4.2 measurement arrangement：
7.4.3 Method of measurement：
（1）The measurement arrangement is given in Figure 5.
（2）To measurement of the POTS splitter attenuation in the ADSL band. and record test result
7.5 Attenuation Distortion in the Voice Band
7.5.1 Purpose：To verify that the POTS Splitter attenuation distortion in the voice band is in compliance with the requirements specified in Table 1.
7.5.2 measurement arrangement：
7.5.3 Method of measurement：
（1）The measurement arrangement is given in Figure 6.
（2）To choose 26AWG 0ft Cable test loop, the insertion loss at 200Hz to 3400Hz test signal from the source to the termination shall be measured and without the POTS Splitter/ZHP-r combination inserted.
（3）The attenuation distortion at 200Hz to 3400Hz test signal from the source to the termination shall be measured and with the POTS Splitter/ZHP-r combination inserted.
（4）The attenuation distortion at 1004Hz test signal from the source to the termination shall be measured and with the POTS Splitter/ZHP-r combination inserted. To compare the attenuation distortion at 200Hz to 3400Hz test signal.
（5）Repeat step (2),(3),(4) and to measurement the attenuation distortion at 3400Hz to 4000Hz test signal. To compare the attenuation distortion at 1004Hz test signal.
（6）To choose 26 AWG 0.5kft , 2.0kft, 5kft Cable test loop, repeat step (2),(3),(4),(5). and record test result
7.6 Delay Distortion in the Voice band
7.6.1 Purpose：To verify that the POTS Splitter delay distortion in the voice band is in compliance with the requirements specified in Table 2.
7.6.2 measurement arrangement：
7.6.3 Method of measurement：
（1）The measurement arrangement is given in Figure 7.
（2）To choose 26AWG 0ft Cable test loop, the signal delay at 600Hz to 3200Hz test signal from the source to the termination shall be measured and without the POTS Splitter/ZHP-r combination inserted.
（3）The signal delay at 600Hz to 3200Hz test signal from the source to the termination shall be measured and with the POTS Splitter/ZHP-r combination inserted. To compare the signal delay for (2).
（4）To choose 26AWG 0ft Cable test loop, the signal delay at 200Hz to 4000Hz test signal from the source to the termination shall be measured and without the POTS Splitter/ZHP-r combination inserted.
（5）The signal delay at 20Hz to 4000Hz test signal from the source to the termination shall be measured and with the POTS Splitter/ZHP-r combination inserted. To compare the signal delay for (4). and record test result
（6）To choose 26 AWG 0.5kft , 2.0kft, 5kft Cable test loop, repeat step (2),(3),(4),(5). and record test result
7.7 Return Loss in the Voice band
7.7.1 Purpose：To verify that the POTS Splitter return loss in the voice band is in compliance with the requirements specified in Table 3.
7.7.2 measurement arrangement：
7.7.3 Method of measurement：
（1）The measurement arrangement is given in Figure 8.
（2）To measurement return loss.
（3）To choose Individual frequencies start at 2200 Hz and sweep to 3400 Hz., repeat step (2),(3). and record test result
7.8 Longitudinal Balance Testing in the Voice band
7.8.1 Purpose：To verify that the POTS Splitter longitudinal balance testing in the voice band is in compliance with the requirements specified in 6.1.
7.8.2 measurement arrangement：
7.8.3 Method of measurement：
（1）The measurement arrangement is given in Figure 9, and a DC bias current of 25mA will be applied.
（2）To measurement longitudinal balance. and record test result
7.9 Transparent Capacitor
7.9.1 Purpose：To verify that the POTS Splitter transparent capacitor is in compliance with the requirements specified in 6.1.
7.9.2 measurement arrangement：
7.9.3 Method of measurement：
（1）The measurement arrangement is given in Figure 10.
（2）To measurement the POTS Splitter capacitance at the POTS interfaces in the frequency range of 20-30 Hz.
（3）To measurement the stray capacitance to ground from either leg (TIP or RING) of the POTS splitter. and record test result
Surge Testing
7.10.1 Purpose：To verify that the POTS Splitter U-R interface after applying the surge test, all the operational functions must work well.
7.10.2 measurement arrangement：
Method of measurement：
（1）The measurement arrangement is given in Figure 11.
（2）Metallic surge wave form :
Type A：
Open Circuit Voltage ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧560μs and peak voltage≧800V.
Short Circuit Current ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧560μs, the surge generator should support over 100A peak current.
Type B：
Open Circuit Voltage ：Front time〔Tf〕≦9μs、decay time 〔Td〕≧720μs and peak voltage≧1000V.
Short Circuit Current ：Front time〔Tf〕≦5μs、decay time 〔Td〕≧320μs, the surge generator should support over 25A peak current.
（3）SW OFF, apply one surge of each polarity between two leads.
（4）SW ON, apply one surge of each polarity between two leads.
（5）To check the POTS Splitter complying with the conformance requirement section 6.1e s

8. ATU-R interface testing
8.1 Transmitter Pass Band PSD Response Testing
8.1.1 Purpose：To verify that the ATU-R transmitter pass band PSD response is in compliance with the requirements specified in 6.2.
8.1.2 measurement arrangement：
8.1.3 Method of measurement：
（1）The measurement arrangement is given in Figure 12.
（2）To check the ATU-R is at handshake state.
（3）To measurement the ATU-R PSD with differential probe and spectrum analyzer in Pass Band.
（4）To measurement the ATU-R PSD with differential probe and spectrum analyzer in low frequency stop band
（5）To add attenuate value and check the ATU-R is at break down state. To reduce attenuate value and check the ATU-R is at handshake state. To measurement the ATU-R in High Frequency Stop Band
8.2 Total Signal Power Limitation
8.2.1 Purpose：To verify that the ATU-R Total Signal Power is in compliance with the requirements specified in 6.2.
8.2.2 measurement arrangement：
8.2.3 Method of measurement：
（1）The measurement arrangement is given in Figure 13.
（2）To check the ATU-R is at handshake state.
（3）To use the Line attenuator to reduce down-Stream signal.
（4）To measurement the Vrms of transmitter signal.
（5）To calculate Total Signal Power = 20 log (Vrms/316mV).and record test result
8.3 ADSL Band Longitudinal Balance
8.3.1 Purpose：To verify that the ADSL Band Longitudinal Balance of the ATU-R is in compliance with the requirements specified in 6.2.
8.3.2 measurement arrangement：
8.3.3 Method of measurement：
（1）The measurement arrangement is given in Figure 14.
（2）To calibrate a procedure for the longitudinal balance tester.
（3）To measurement the ADSL Band Longitudinal Balance.
（4）To calculate LB= 20log |EL/Em| dB. and record test result
8.4 Input Impedance
8.4.1 Purpose：To verify that the ATU-R input impedance is in compliance with the requirements specified in 6.2.
8.4.2 measurement arrangement：
8.4.3 Method of measurement：
（1）The measurement arrangement is given in Figure 15.
（2）To set LCR impedance tester output signal (3V, 4 kHz).
（3）To measurement impedance.
（4）To measurement capacitor.
（5）Record test result. and record test result
8.5 Surge Testing
8.5.1 Purpose：To verify that the ATU-R after applying the surge test, all the operational functions must work well.
8.5.2 measurement arrangement：
Method of measurement：
a. Metallic：
（1）The measurement arrangement is given in Figure 16.
（2）Metallic surge wave form :
Type A：
Open Voltage ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧560μs and peak voltage≧800V.
Short Current ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧560μs, the surge generator should support over 100A peak current.
Type B：
Open Circuit Voltage ：Front time〔Tf〕≦9μs、decay time 〔Td〕≧720μs and peak voltage≧1000V.
Short Circuit Current ：Front time〔Tf〕≦5μs、decay time 〔Td〕≧320μs, the surge generator should support over 25A peak current.
（3）Ａpply one surge of each polarity between Tip and Ring .
（4）To check the ATU-R complying with the conformance requirement section 6.2.
b. Longitudinal：
（1）The measurement arrangement is given in Figure 16.
（2）Longitudinal surge wave form :
Type A：
Open Circuit Voltage ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧160μs and peak voltage≧1500V.
Short Circuit Current ：Front time〔Tf〕≦10μs、decay time 〔Td〕≧160μs, the surge generator should support over 200A peak current.
Type B：
Open Circuit Voltage ：Front time〔Tf〕≦9μs、decay time 〔Td〕≧720μs and peak voltage≧1500V.
Short Circuit Current ：Front time〔Tf〕≦5μs、decay time 〔Td〕≧320μs, the surge generator should support over 37.5A peak current.
（3）Ａpply one surge of each polarity between Tip and Ring and ground (or cover).
（4）To check the ATU-R complying with the conformance requirement section 6.2.
c. AC Power Line Surge Test:
（1）The measurement arrangement is given in Figure 17.
（2）surge wave form : Front time〔Tf〕≦2μs、decay time 〔Td〕≧10μs and peak voltage≧2500V. the surge generator should support over 1000A peak current.
（3）Apply the above surge wave form on the AC power line of ATU-R, while ATU-R is powered on , and then change the polarity to test it three times. There was an interval of 60 seconds between every other times.
（4）To check the ATU-R power interface complying with the conformance requirement mpare the si