docsPnmCmtsDsOfdmNoisePwrRatioTable
DOCS-PNM-MIB ·
.1.3.6.1.4.1.4491.2.1.27.1.3.2
Object
table
The purpose of downstream NPR measurement is to view the noise, interference and intermodulation products underlying a portion of the OFDM signal. As an out-of-service test, the CMTS can define an exclusion band of zero-valued subcarriers which forms a spectral notch in the downstream OFDM signal for all profiles of a given downstream channel. The CM provides its normal spectral capture measurements, or symbol capture, which permit analysis of the notch depth. A possible use case is to observe LTE interference occurring within an OFDM band; another is to observe intermodulation products resulting from signal-level alignment issues. Since the introduction and removal of a notch affects all profiles, causing possible link downtime, this feature is intended for infrequent maintenance.
Context
- MIB
- DOCS-PNM-MIB
- OID
.1.3.6.1.4.1.4491.2.1.27.1.3.2- Type
- table
- Status
- current
- Parent
- docsPnmCmtsObjects
- Siblings
- 7
- Children
- 1
Syntax
No syntax metadata recorded.
Values & Constraints
No enumerated values or constraints recorded.
Related Objects
Sibling Objects
| Object | Type | Syntax | OID |
|---|---|---|---|
| docsPnmCmtsDsOfdmSymCapTable The purpose of downstream symbol capture is to provide partial
functionality of a network analyzer to analyze the response of the
cable plant.
At the CMTS, the transmit… | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.1 |
| docsPnmCmtsUsOfdmaAQProbeTable The purpose of upstream capture is to measure plant response and view
the underlying noise floor, by capturing at least one OFDMA symbol
during a scheduled active or quiet probe. … | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.3 |
| docsPnmCmtsUsImpNoiseTable This table provides statistics of burst/impulse noise occurring in a
selected narrow band. A bandpass filter is positioned in an unoccupied
upstream band. A threshold is set, ener… | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.4 |
| docsPnmCmtsUsHistTable The purpose of the upstream histogram is to provide a measurement of
nonlinear effects in the channel such as amplifier compression and
laser clipping. For example, laser clipping… | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.5 |
| docsPnmCmtsUsOfdmaRxPwrTable The purpose of the upstream channel power metric is to provide an
estimate of the total received power in a specified OFDMA channel at
the F connector input of the CMTS line card … | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.6 |
| docsPnmCmtsUsOfdmaRxMerTable This item provides measurements of the upstream receive modulation
error ratio (RxMER) for each subcarrier. The CMTS measures the RxMER
using an upstream probe, which is not subje… | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.7 |
| docsPnmCmtsUsSpecAnTable The upstream triggered spectrum analysis measurement provides a
wideband spectrum analyzer function in the CMTS which can be triggered
to examine desired upstream transmissions as… | table | - | .1.3.6.1.4.1.4491.2.1.27.1.3.8 |
Child Objects
| Object | Type | Syntax | OID |
|---|---|---|---|
| docsPnmCmtsDsOfdmNoisePwrRatioEntry The conceptual row of the 'docsPnmCmtsDsOfdmNoisePwrRatioTable'. An instance
is dynamically created and exists for an associated ifIndex of the
physical downstream channel upon wh… | row | - | .1.3.6.1.4.1.4491.2.1.27.1.3.2.1 |