Volpe Firm | Technology Blog

23 11, 2021

Why RxMER?

Mia Colabrese2021-11-23T16:42:11-05:00November 23rd, 2021|

The DOCSIS 3.1 PHY specification includes several PNM parameters and tests. One of the most useful downstream tests for OFDM is called receive modulation error ratio (RxMER) per subcarrier. RxMER per subcarrier provides an MER measurement for each subcarrier in the OFDM (downstream) or OFDMA (upstream) channel. This means if an OFDM channel has 7600 subcarriers, the RxMER per subcarrier data will provide 7600 MER results, one corresponding to each subcarrier. When plotted, it looks like a spectrum analyzer chart, but has different meanings. See Figure 1 for

3 11, 2021

PTP Clocks

Mia Colabrese2021-11-03T12:30:23-04:00November 3rd, 2021|

In this episode Brady Volpe of Nimble This and The Volpe Firm, discusses PTP clocks with subject matter experts Jim Olsen from Microchip and Rob Jodrie from Syncworks. This discussion includes a very high level break down of PTP profiles and why you should care? The evolution of PTP, Boundary clocks, best practices and things to look out for. You may think this is not a big topic but this is something that impacts all operators big, medium or small when deploying distributed access architecture (DAA) such as

2 11, 2021

SCTE EXPO 2021 Wrap-up

Mia Colabrese2024-11-21T13:37:28-05:00November 2nd, 2021|

In this episode Brady Volpe of Nimble This and The Volpe Firm, and John Downey of Cisco discuss the best of SCTE EXPO 2021 The discussion is on all things DOCSIS. Tips, suggestions and recommendations. Another power hour of cable. The best of SCTE EXPO 2021: SCTE EXPO 2021 wrap up Exceptional show, watch till November 14th 2021 SCTE EXPO 2021 papers on NCTAtechnicalpapers.com SCTE presentations on SCTE EXPO 2021 site Brady's presentations: You can catch Brady Volpe In the following sessions Advanced Analytics 1 of 3:

3 09, 2021

Interpreting Full Band Capture and RxMER

Mia Colabrese2021-09-03T10:44:50-04:00September 3rd, 2021|

In this episode Brady Volpe of Nimble This and The Volpe Firm, and John Downey of Cisco discuss interpreting Full Band Capture (FBC) and RxMER which is the MER of the subcarriers in the OFDM channel. Cable is a technology business and we seem to always come up with new terms and new things to understand and interpret. FBC has been around now but still not everyone knows what it means and how to understand it correctly. RxMER is a bit newer but can still be mysterious

23 08, 2021

DOCSIS is Green

Mia Colabrese2021-08-23T11:28:23-04:00August 23rd, 2021|

DOCSIS is Green (full length). Shorter and cleaner version is seen in Broadband Library DOCSIS Going Green. The simplest solution is almost always the best. Through technological advancements we can do more with less. There are important discussions happening about green initiatives in our industry. Usually on the consumer electronics side. According to the NCTA “Cable operators, video programmers, equipment manufacturers, research labs and others are now providing a more energy efficient experience that is saving consumers millions of dollars in energy bills and preventing millions of metric tons of

20 08, 2021

Cisco vCMTS

Mia Colabrese2021-08-23T11:57:31-04:00August 20th, 2021|

Cisco vCMTS? Brady Volpe founder of The Volpe Firm and Nimble This, John Downey and Jason Miller Technical Marketing Engineer of Cisco discuss Cisco's virtual CMTS (vCMTS). The topic came up during ANGACOMs 2021 presentation. I didn't know Cisco even had a vCMTS, did you? Well, let's find out what they are doing and if they are really taking away the CLI as discussed at ANGACOM. The discussion is on all things DOCSIS. Tips, suggestions and recommendations. Another power hour of cable with Brady Volpe and John Downey CMTS

15 07, 2021

DOCSIS Primary Channel Impaired Downstream Troubleshooting

Mia Colabrese2023-02-17T18:41:43-05:00July 15th, 2021|

In this episode Brady and John discuss what happens to an impaired DOCSIS Primary channel & ANGA COM highlights. When an impaired DOCSIS Primary channel occurs, do to one ore more impairment, how does it impact other DOCSIS channels? Primary being a type of "management" SC-QAM channel. Does it make a difference? We also cover the top content from the ANGA COM show. Didn't have time to watch all of the ANGA COM show material. No problem. Brady and John will make sure your up to speed

4 06, 2021

Machine Learning and PNM

Mia Colabrese2021-08-13T08:43:30-04:00June 4th, 2021|

Machine Learning and PNM Yes, it’s real and yes, it’s deployed and working! The day has arrived, Skynet is here! [1]. Fortunately, no to Skynet and in more good news our machines are in the cable plant and they are learning. They have been deployed into the cable world and they are finding the nasty impairments we knew were there. Machine learning and PNM are making the technician’s job easier on many levels. It’s much easier to find the impairments, it’s significantly easier for technicians to know what

3 06, 2021

Recommendations to resolving DOCSIS 3.1 cable modems crashing with OFDMA

Mia Colabrese2021-06-03T12:49:12-04:00June 3rd, 2021|

Recommendations to resolving DOCSIS 3.1 cable modems crashing with OFDMA Place OFDMA channels above 42 MHz: For those fortunate with 5-65 MHz or 5-85 MHz return paths, keeping four 6.4 MHz SC-QAM signals below 42 MHz and then loading one OFDMA channel above 42 MHz is ideal. Your SC-QAM channels should be fully optimized with dynamic profile modulation up to 64-QAM. Then, by placing your OFDMA channel above 42 MHz, you’re ensuring its likely to be in a low noise environment. A bonus is that subscribers with in-home amplifiers

3 06, 2021

Cable Modems Crashing with OFDMA

Mia Colabrese2021-06-07T14:51:59-04:00June 3rd, 2021|

Why are the DOCSIS 3.1 Cable Modems Crashing with OFDMA This too shall pass. Yes, we’ve seen this before: OFDMA + DBC = BSoD Yes, you have experienced it. Either as a subscriber or technician. The cable modem is on but there is no data flowing through it. Reboot the modem and it works again. It’s the equivalent of the Microsoft Windows blue screen of death (BSoD) and it’s back with a vengeance for cable operators running DOCSIS 3.1 OFDMA with a noisy upstream. What gives? I will