ANSI SCTE-115-2011 pdf download Test Method for Reverse Path (Upstream) Intermodulation Using Two Carriers
1.0 SCOPE
1.1 This test procedure defines a method of measurement of intermodulation distortion in the reverse “upstream” path of Cable Telecommunications equipment. This test procedure uses two signal sources (CW sources) at the input of the device under test and uses a spectrum analyzer to measure the discrete second and third intermodulation distortions generated by the device under test.
1.2 This procedure is a very unique procedure for reverse “upstream” measurements and is distinguished from other similar procedures in the following ways:
Designed for two-way actives
Two port measurement, reverse direction only
Injects two reverse carriers and measure intermodulation distortion in the reverse band
Used to verify performance of reverse path amplifier For similar procedures, please reference the following:
SCTE 145 2008: Test Method for Second Harmonic Distortion of Passives Using a Single Carrier
SCTE 126 2006: Test Method for Distortion of 2-way Active Amplifier Caused by Insufficient Isolation of Built in Diplex Filter
SCTE 109 2010: Test Method for Common Path Distortion
Each of these procedures is targeted at a different measurement for a unique purpose. They are independent, are specifically applicable to the device being measured, use the test equipment commonly available at the manufacturing sites used to make the device being tested, and directly measure the impairment that must be controlled. The key differences are whether they are designed for actives or passives and whether they are single port or two port measurements. Other differences are the types of distortion products being measured and the filters required to do so.
2.0 NORMATIVE REFERENCES The following document contains provisions, which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreement based on this standard are encouraged to investigate the possibility of applying the most recent editions of the documents listed below.