ANSI SCTE 132-2019 pdf free download – Test Method for Reverse Path (Upstream) bit error rate.
1. Introduction
1.1. Executive Summary
This procedure defines a method of measurement for bit error rate(BER) in the return path of activeCable Telecommunications equipment. It is intended for measurement of 75-ohm. See the CableTelecommunications Testing Guidelines document, ANSI/SCTE 96 2013, for a discussion of propertesting techniques.
1.2. Scope
Since the introduction of Cablelabs DOCSIS 3.1 specifications,QAM channels have been sharing theupstream spectrum with OFDMA channels. Through Proactive Network Maintenance (PNM), DOCSIS3.1 specifications leverage CMTS and cable modem features and capabilities to enable measurement andreporting of network conditions and their effects. These measurements include FEC statistics (BER) asmeasured by the CMTS on upstream OFDMA channels.Accordingly, the scope of this test was notbroadened to cover OFDMA channels. Instead, the reader is referred to the DOCSIS 3.1 specifications.For bit error rate measurements in the forward path see ANSI/SCTE 121 2011.
2. Normative References
The following documents contain provisions,which, through reference in this text, constitute provisionsof this document. At the time of Subcommittee approval, the editions indicated were valid. All documentsare subject to revision; and while parties to any agreement based on this document are encouraged to investigate the possibility of applying the most recent editions of the documents listed below, they arereminded that newer editions of those documents might not be compatible with the referenced version.
2.1.SCTE References
• ANSI/SCTE 96 2013: Cable Telecommunications Testing Guidelines2.2. Standards from Other Organizations
• DOCSIS 3.1, Physical Layer Specification, CM-SP-PHYv3.1-113-171220, December 20,2017,
Cable Television Laboratories,Inc.
2.3. Published Materials
• No normative references are applicable.3. Informative References
The following documents might provide valuable information to the reader but are not required whencomplying with this document.
3.1. SCTE References
• ANSI/SCTE 121 2011: Test Method for Downstream Bit Error Rate
3.2. Standards from Other Organizations
• No informative references are applicable.
3.3. Published Materials
• No informative references are applicable.
6. Equipment
Only equipment specific to this procedure is described in detail here. ANSI/SCTE 96 2008: Cable Telecommunications Testing Guidelines, should be consulted for further information on all other equipment
6.1. Equipment
6.1.1. Digital Loading
Digital loading can consist of individual QAM channels or broadbandsimulated digital noise loading (SDNL)
A. Equipment if using Simulated Digital Noise Loading (SDNL)
Broadband Noise Generator
Bandwidth equal to or wider than specified channel planVariable output power or incorporates an external variable
attenuator.
Appropriate bandpass (high/low pass) filter to shape the noise loadingin accordance with the specified channel plan
16 dB minimum return loss,75ohm
.+/- 1OMHz from edge frequency, >40 dB rejection+/- 0.25 dB flatness
-<1.5 dB insertion loss
. Notch filters (channel deletion filters)
Center frequency = Center frequency of test channel16 dB minimum return loss, 75ohm
Bandwidth sufficient for the modulation under test, >50 dBrejection
+/- 2MHz from band edge,<3.0 dB insertion loss+/-0.25 dB flatness in the passband
<1.5 dB insertion loss
B. Equipment if using individual QAM channels for loading
• QAM generators, equal in bandwidth to channel under test(Quantity =digital bandwith/QAM bandwidth -1)
• RF combiner, used to combine QAM generators
6.1.2. Common Equipment
• Transmitter for conversion of data to a RF modulated signal in the range of return path frequency.
• Receiver for conversion of RF signals in the range of return path signals to data.ANSI SCTE 132 pdf download.