51
Testing Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

  • Upload
    lyminh

  • View
    265

  • Download
    2

Embed Size (px)

Citation preview

Page 1: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Testing Upstream and Downstream DOCSIS 3.1 Devices April 2015

Steve Hall

DOCSIS 3.1 Business Development Manager

Page 2: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Agenda

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and reporting key metrics

such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and repair issues that

cause BER.

3. Understanding the complexities of demodulating and measuring low frequency, small grant

upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS 3.1 signals.

2

Page 3: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and reporting key

metrics such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and repair issues that

cause BER.

3. Understanding the complexities of demodulating and measuring low frequency, small grant

upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS 3.1 signals.

3

Agenda

Page 4: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Physical Layer Link Channel (PLC) OFDM Channel Descriptor (OCD)

Downstream Profile Descriptor (DPD) messages

DOCSIS 3.1 Signal Format

4

Page 5: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

NCP

Fields

Data

Fields

DOCSIS 3.1 Signal Format

5

Page 6: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Automatic Demodulation of Downstream signals in VSA

- New DOCSIS3.1 Downstream measurement option BHM for 89601B VSA

(BHM)Key features:

- Automatic setup for downstream configuration by demodulating and

decoding:

Physical Layer Link Channel (PLC)

OFDM Channel Descriptor (OCD)

Downstream Profile Descriptor (DPD) messages

- Decode the NCP and locate the codewords for each profile

- Demod the data for each profile - MER

- Post-process MER & BER/PER measurements to accumulate over

successive acquisition.

© Keysight

Technologies 2015 6

Page 7: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Result Traces – DOCSIS3.1 Downstream

Step 1 – detect and decode PLC Physical Layer Link Channel

Step 2 – detect and decode OCD OFDM Channel Descriptor

(not necessarily sent every frame as per standard)

Step 3 – detect and decode DPD Downstream Profile Descriptor

© Keysight

Technologies 2015 7

Page 8: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Result Traces – DOCSIS3.1 Downstream

Initial performance results…

© Keysight

Technologies 2015 8

Page 9: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Result Traces – DOCSIS3.1 Downstream

Report Profile Results

Report NCP Results

De

sc

rip

tio

n o

f R

es

ult

s

© Keysight

Technologies 2015 9

Page 10: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Result Traces – DOCSIS3.1 Downstream

© Keysight

Technologies 2015 10

Page 11: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Result Traces – DOCSIS3.1 Downstream

© Keysight

Technologies 2015 11

Page 12: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

MER Measurement

Hardware Positioning

$

Max 160MHz

Demod BW + RF Measurements

Max 750 MHz

Demod BW

Max 510 MHz

Demod BW + RF Measurements

MER

12

© Keysight

Technologies 2015

Page 13: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Introducing the N9040B UXA Signal Analyzer

8.4/13.6/26.5

GHz

Streamlined

touch driven

interface

Full BW RTSA

Up to 510

MHz analysis

BW

89600 VSA &

N9068C

Phase Noise

App

Industry

Leading

Phase noise © Keysight

Technologies 2015 13

Page 14: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

– U5303A PCIe High-Speed

Digitizer

• PCIe rack mount expansion

chassis

• Desktop PC

– UXA N9040B Signal Analyzer

• Install 89600 VSA software on

Windows 7 OS or on an

external PC

© Keysight

Technologies 2015

89601B Vector Signal Analyzer

OR

Hardware Platforms: U5303A digitizer or X-Series Spectrum Analyzer

Page 15: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Hardware Platforms: U5303A digitizer and X-Series Spectrum Analyzer

Preserve your X-Series investment!

Combine the power of the PCIe Digitizer Modulation Measurements

with the power of the PXA/UXA RF Measurememts.

Personal Cpmputer

© Keysight

Technologies 2015 15

Page 16: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Agenda

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and reporting key metrics

such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and repair issues

that cause BER.

3. Understanding the complexities of demodulating and measuring low frequency, small grant

upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS 3.1 signals.

16

Page 17: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Device Under

Test

DOCSIS

Frame

Generator

M8190A

To BER or not to BER:

BER says everything is “working nicely” – or that it is NOT!

Hours of testing complete… …yet BER fails!

How do you determine WHY your Bit Error Rate is failing?

Golden Receiver Cable Modem

• CMTS (single ended)

• Optical Transport

• Amplifier

BER

What causes bit errors?

• Clipping?

• Noise?

• Compression?

• Interference?

How and where do they show up other than in an

accumulated over-time BER test?

• Rapid fire in-channel and adjacent-channel energy

spikes?

• Increased unexpected signal amplitude?

• Spurious emissions?

• Reduced Adjacent Channel Power performance? © Keysight

Technologies 2015 17

Page 18: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

How do DOWNSTREAM events manifest themselves?

These events show up at various times and places

and are distinguishable as perturbations in the

frequency domain!

By building a very flexible mask around the spectrum,

these perturbations can be trapped, recorded,

analyzed and subsequently – questions answered! © Keysight

Technologies 2015 18

Page 19: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

The test steps…

Monitor Transient Spectral Behavior

in Real Time

Trigger on Transient Spectral Behavior in

Real Time

Record Transient Spectral Behavior Including Behavior

Leading up to the event

Determine if the Transient Spectral

Behavior Caused Bit Errors

Determine Root Cause and Repair

Issue

19

Page 20: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

The Tools: How are transients found?

Real Time Spectrum Analysis

Watch for the transient event…

20

Page 21: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

The Tools: How are transients found?

Real Time Spectrum Analysis

Watch for the transient event…

21

Page 22: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Frequency Mask trigger

Catches the transient…

The Tools: How are transients found?

Real Time Spectrum Analysis

Watch for the transient event…

22

Page 23: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Set up frequency Mask Trgger in VSA…

The Tools: How are transients found?

Real Time Spectrum Analysis + Vector Signal Analysis

Watch for the transient event…

23

Page 24: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Multiple Domain Insight

Watch for the transient event…

24

Page 25: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Note spectral behavior of transient event…

Multiple Domain Insight

Watch for the transient event…

25

Page 26: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Transient Event Impact on Constellation

Impact on MER

The Tools: How are transients found?

26

Page 27: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

DUT (Amplifier/Optical

Transport or CMTS)

M8190A (DOCSIS 3.1 Frame

Generator)

Real Time Spectrum

Analyzer uses

frequency Mask

Trigger to detect

unwanted energy in

and around the

desired signals.

Vector Signal Analyzer begins recording triggered by a violation detected by

the Real Time Spectrum Analyzer including a pre-trigger window

Monitor Transient Spectral Behavior

in Real Time

Trigger on Transient Spectral Behavior in

Real Time

Record Transient Spectral Behavior Including Behavior

Leading up to the event

The test steps…

© Keysight

Technologies 2015 27

Page 28: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Study demodulation test results for the gap

free recording to answer questions like:

Was signal quality impacted buy the event

that caused the recording to be triggered?

Calculate and

analyze BER

results for the

entire gap-free

recorded frames in

order to answer the

question: Did THIS

event cause bit

errors?

Determine if the Transient Spectral

Behavior Caused Bit Errors

Determine Root Cause and Repair

Issue

© Keysight

Technologies 2015 28

Page 29: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Automating the process…

Test Controller

Create scripts to automate and record

events.

Monitor Transient Spectral Behavior

in Real Time

Trigger on Transient Spectral Behavior in

Real Time

Record Transient Spectral Behavior Including Behavior

Leading up to the event

Determine if the Transient Spectral

Behavior Caused Bit Errors

Determine Root Cause and Repair

Issue

© Keysight

Technologies 2015 29

Page 30: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Testing for the Real Upstream Environment…

CM 1

CM 2

CM 3

CM n

Node Node FIBER

CMTS

Environmental

Interference

How tolerant is this system of this signal?

© Keysight

Technologies 2015 30

Page 31: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Testing for the Real Upstream Environment…

Node Node FIBER

Environmental

Interference

How tolerant is this system of this signal?

Upstream

Generator

Plus

Impairments

Real Time

Spectrum

Analyzer

Plus

VSA

© Keysight

Technologies 2015 31

Page 32: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Real Time Spectrum Analysis and Event recording…

Step 2: Initiate Signal recording!

Step 3: Post-process using Multi-

measurements to show impact during

the event… Step 4: Post-process Multimeasurements

Show recovery after the event the event…

Step 1: RTSA Trigger Mask

© Keysight

Technologies 2015 32

Page 33: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Agenda

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and reporting key metrics

such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and repair issues that

cause BER.

3. Understanding the complexities of demodulating and measuring low frequency, small

grant upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS 3.1 signals.

33

Page 34: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Hybrid Fiber

Coax (HFC)

Network

Stability of MER Measurements at Low Grant %

CMTS

1

96MHz Channel

Spectrum

3

4

5

2

OFDMA

96MHz Channel

Cable

Modems

OFDMA: Low-grant signals are those where less

than about half of the subcarriers are active, and the

remainder are transmitted as nulls.

1 2 3 4 5

© Keysight

Technologies 2015 34

Page 35: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Stability of MER Measurements at Low Grant %

Measurement Challenge: Vector Signal Analysis synchronization algorithms are

optimized for signals with a relatively high grant percentage.

5% grant

96 subcarriers

96 MHz Acquisition BW

DC

Sample Freq. 102.4 MHz

Center Freq. 53 MHz

2048 point FFT

© Keysight

Technologies 2015 35

Page 36: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Stability of MER Measurements at Low Grant %

5% grant

96 subcarriers

96 MHz Acquisition BW

DC

Sample Freq. 102.4 MHz

Center Freq. 53 MHz

2048 point FFT

Mathematically

equivalent to:

Sample Freq. 6.4 MHz

Center Freq. 8 MHz

128 point FFT

100% grant

96 subcarriers

~5 MHz Acquisition BW

Measurement Approach: Reconfigure existing measurements to zoom in on the active

subcarriers only. Thus, rather than analyzing a small percentage of a large FFT block,

the demodulator processes a smaller FFT block that is almost fully-populated!

Smaller acquisition BW improves SNR to the sync algorithms, stabilizes MER readings. Mathematically, the two

approaches are identical – there is no effect on the calculation of MER, carrier frequency error, symbol clock error,

or other measurement results.

Automatic Bandwidth Translation

Compliments of Optimizer Macro!

© Keysight

Technologies 2015 36

Page 37: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Stability of MER Measurements at Low Grant %

“Optimize” VSA Macro

© Keysight

Technologies 2015 37

Page 38: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Results Comparison

Demod config: 2K FFT – 5% grant Demod config: 128 FFT – 100% grant

Avg. MER: ~37 dB

Variance: ±5 dB

Sync stability: 50%

Avg. MER: 53.8 dB

Variance: ±1 dB

Sync stability: 100%

Identical hardware, identical input signal:

© Keysight

Technologies 2015 38

Page 39: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Stability of MER Measurements at Low Grant %

Small Grant 1 Small Grant 2

Setting the grants side by

side creates a challenging

measurement scenario.

Hybrid Fiber

Coax (HFC)

Network

CMTS

1

96MHz Channel

Spectrum

3

4

5

2

OFDMA

96MHz Channel

Cable

Modems

1 2 3 4 5

© Keysight

Technologies 2015 39

Page 40: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Reconfiguring OFDM for Synchronized ACP

• The DOCSIS 3.1 PHY specification requires that Adjacent Channel

Power be measured in the spectrum regions directly adjacent to

the transmitted signal, starting at one subcarrier spacing (25 or 50

kHz) from the outermost active subcarriers.

• However, even well-windowed OFDM signals will have significant

sinX/X modulation sidebands that extend into this region which are

visible when viewed on a traditional swept spectrum analyzer.

© Keysight

Technologies 2015 40

Page 41: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Reconfiguring OFDM for Synchronized ACP

• The ACP specification is not meant to include these sidebands, but

rather to measure only the unwanted noise and distortion that may

accompany them.

• In order to separate these components, the spec requires that ACP

measurements at offsets of 2 MHz or less be performed

synchronously - that is, sampled at the same frequency and in

phase with the underlying OFDM modulation clock.

• This suppresses all orthogonal (modulation-related) energy,

leaving only the non-linear distortion to be summed.

© Keysight

Technologies 2015 41

Page 42: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Reconfiguring OFDM for Synchronized ACP

Adds extra “null” subcarriers to the OFDM

demod configuration.

Configure analyzer to display the null

subcarriers.

Read ACP from VSA spectrum display

using band power markers.

Optimizer

VSA

© Keysight

Technologies 2015 42

Page 43: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

Agenda

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and reporting key metrics

such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and repair issues that

cause BER.

3. Understanding the complexities of demodulating and measuring low frequency, small grant

upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS 3.1 signals.

© Keysight

Technologies 2015 43

Page 44: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

M8190A – Main Features

Breakthrough performance

Up to 90 dBc SFDR for

Reliable and repeatable measurements

14 bit 8 Gsa/s or 12 bit 12 Gsa/s

Variable sample rate from 125 Msa/s to 8/12 Gsa/s

2 GSa memory for

Long play time

5 GHz analog bandwidth

For today’s and tomorrows apps

Operation with leading

software platforms

© Keysight

Technologies 2015 44

Page 45: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

M9099T Waveform Creator - Downstream

Page 46: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

M9099T Waveform Creator - Upstream

Page 47: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

SystemVue Libraries

© Keysight

Technologies 2015 47

Page 48: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

ATP PHY 31 Spectrum Loading

Cable Load

Signals

Notch

Cable Load

Signals

© Keysight

Technologies 2015 48

Page 49: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

ATP PHY 31 Interfering spectrum

© Keysight

Technologies 2015 49

Page 50: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015 50

Output of M8190A as per settings described above

DOCSIS 3.0 = 158

channels, 6 MHz spacing

DOCSIS 3.1, 1901

active subcarriers

Page 51: DOCSIS 3.1 Upstream Signal Analysis - Keysight · PDF fileTesting Upstream and Downstream DOCSIS 3.1 Devices April 2015 Steve Hall DOCSIS 3.1 Business Development Manager

Page

© Keysight

Technologies 2015

Questions?

1. Decoding and demodulating a real downstream DOCSIS 3.1 signal and

reporting key metrics such as MER and BER.

2. Combining powerful trigger and recording techniques to detect, identify and

repair issues that cause BER.

3. Understanding the complexities of demodulating and measuring low frequency,

small grant upstream signals.

4. Generating in-channel and out-of-channel upstream and downstream DOCSIS

3.1 signals.

51