Juniper Networks G10 CMTS manual Average Upstream Noise Measurement Example

Noise Measurement Methodology

•Figure 23: Average Upstream Noise Measurement Example

•	Peak Upstream Noise Measurement
•
•	This section defines a procedure for taking the peak upstream noise measurements required
•
•	as part of the RF plant and HFC environment characterization. We recommend that you take
•	a sample of 10 percent of the nodes terminated at the installation site. Table 34 provides the
•	appropriate setup configuration settings for the HP 8591C spectrum analyzer.
•
•

•Table 34: Peak Noise Spectrum Analyzer Setup

•
•	Setting		Value
•
	Start frequency		2 MHz
•
	Stop frequency		45 MHz
•
	Resolution bandwidth		100 kHz
•
•	Video bandwidth		30 kHz
•
	Scale		5 dB/div
•
	Internal amplifier		Off
•
•	Attenuator		0 dB
•
	Reference level of headend		0 dBmV
•
	Max Hold		1 minute
•
•
•	1.	Connect the spectrum analyzer to the selected upstream signal at the upstream splitter
•
		or at the CMTS upstream port.
•
•	2.	Configure the spectrum analyzer using the values defined in Table 34.
•
•	3.	Start the measurement.

•
•	After completing the measurement, the analyzer display should resemble Figure 24 on
•
	page 85.
•

84 JUNOSg 3.0 G10 CMTS Hardware Guide