- Spectral Analysis Software
- RPM Software Suite
The Trilithic DIA Suite is a powerful tool for analyzing the long-term performance of the
Return Path, and for determining the suitability of selected bands for return services. The
Suite is unmatched in its flexibility and ease of use, enabling the operator to identify
low-level, chronic problems long before they can disrupt return services. Power Summing, a
unique feature of the DIA Suite, can re-compute spectral data to evaluate ingress severity
at several near-DOCSIS bandwidths, giving an accurate appraisal of the return path's ability
to carry real-world traffic. DIA Components, CompressR and ProfilR CompressR is normally
co-located on the system controller with IngressManagR Monitoring Software. Usually, it is
set to operate in the background," continually summarizing and evaluating reverse spectral
records generated by IngressManagR. CompressR can perform several computations on the
arriving data, based on limits selectable by the operator. These include:
- The calculated maximum, minimum and average ingress values for each connected node, in intervals of a few minutes to an hour
- The calculated percent of measurements, at each return frequency, that exceeded one or more user-set limits during a settable interval
- The availability of selectable bandwidths at a succession of return frequencies
Computed results are stored as an Access-compatible data base in a hard drive data file.
CompressR can also process stored spectral data from previously-archived files, and build
summaries of historical trends spanning weeks or months. ProfilR is a report-generating
application that interprets ingress summaries compiled by CompressR , reporting analyses in
graphical format or as tabular reports. Because it works from summaries, rather than raw
data, ProfilR operates swiftly, allowing an operator to analyze a large number of records
with the minimum processing delay.
ProfilR reports cover the following parameters:
- The Max/Min/Avg. levels of noise, ingress and traffic levels over specified intervals
- The Average Discrete Ingress Probability
- Ingress Threshold Probability
- Specific Frequency Discrete Ingress Probability
- Specific Channel Discrete Ingress Probability
To facilitate comparisons, data for several nodes may be displayed simultaneously. Each
graph has a handy marker function which numerically reads out the value of any selected
point. A "click and drag" Zoom function makes it easy to home in on a segment of the graph
that is of special interest. All graphs can be stored for later recall.
Power Summing, a Unique DIA Feature
Much like a spectrum analyzer, the Guardian SST Return Analyzer analyzes return band ingress
in a series of adjacent resolution bandwidths, "slices" of the spectrum each a few hundred
kHz wide. However, most return services span several analyzer resolution bandwidths. In
other ingress measurement systems this can cause errors, including underestimation of
impulse ingress power and overestimation of coherent ingress (beats, common path
distortions, etc). CompressR solves this problem by summing the ingress power in a settable
number of adjacent resolution bandwidths, allowing evaluation of ingress levels in
bandwidths similar to those actually used by digital services.
DIA Displays MAX/MIN/AVG
Displays the Max, Min and Avg. levels - vs - frequency. Data for one or more nodes can be
viewed sequentially by time increment. Time increments may be advanced either manually or
automatically.
Waterfall & Power Summing Unavailability Reports
Displays successive traces of ingress levels or channel unavailability over time. With
amplitude or channel unavailability displayed as variations in color, frequency on the y
axis and the time on the x axis for the selected node.
Ingress Threshold Probability Report
Plots the unavailability as the percent of times the ingress level at each frequency crosses
any of the four user-set thresholds for the specified period, by frequency.
Specific Frequency Discrete Ingress Probability Signal Report
Plots the unavailability as the percent of threshold violations for each of the four user
thresholds for each time increment, for a selected frequency.
Specific Channel Discrete Ingress Probability Signal Report
Plots channel unavailability for a specified frequency band (channel or service) vs. time
for each of the 4 thresholds.
The Average Discrete Ingress Probability Signal Report
Calculates the average probability that a node's ingress will exceed one to four thresholds
over a user-specified time interval. The ADISP is a useful "Figure of Merit" for assessing a
node's overall performance over time.
