Do you mean upstream OFDMA or downstream OFDM? I thought most areas had at least 1 downstream OFDM channel to be compatible with DOCSIS 3.1 and 940Mbps (AKA Go Super Fast) speed tier.

From what I understand, you want to see a lot of correctable errors on the OFDM channel because that means it's running at its maximum possible speed. When you start seeing uncorrectable errors, that's when you should worry. I think the messages you're seeing are just the modem shuffling around OFDM profiles for maximum performance.

The Next Codeword Pointer (NCP) is a portion of the downstream OFDM channel which is dedicated to carry information about the mapping of FEC codewords to subcarriers within a symbol. NCP is generally considered a part of the Downstream Convergence Layer. [DOCSIS PHYv3.1] includes a detailed description of the NCP.

Only Channel 33 is an issue which is OFDM PLC. All other channels have no correctable or uncorrectable errors in the last 24 hours. There are about 43 0million correctable errors on Channel 33 in the last 36 hours, no uncorrectable errors. They climb at an astonishing rate. As you may be able to tell, signal is 10.8 dBmV, SNR is 45.1.

dave9 would be the best source but I think the OFDM(A) channels are your overall circuits. These circuits are then divided into separate channels: 32 and 4. Therefore the overall circuits wouldn't be individually locked. I could be wrong and sure I am.

Basically upstream OFDM is being enabled in some areas along with a extra downstream OFDM channel. No new upstream speeds have been announced but I predict they are coming. Seems if you have 8 upstream channels you are close to an upgrade.

Question: Consider an OFDM system. Assume that the total number of samples for DFT and IDFT is 2. The total number of sub carriers is 2. One sample of cyclic prefix is added to each OFDM symbol. Each packet consists of one OFDM symbol for channel estimation followed by one or more OFDM symbols for data transmission.

2024年6月19日 · But event log shows continuous type 16 FEC errors with around 1 - 2 min intervals. OFDM/OFDMA Profile ID ...

Low SNR on the OFDM channel (downstream channel 159) is probably causing the uncorrectables. OFDM is for DOCSIS 3.1 that is why the light switches. I would bypass the router for a hour and see if the VPN is still effected. If so, schedule a technician.

Question: Consider an OFDM system with N=256 subcarriers in 5MHz of bandwidth, with a carrier of fc=2GHz and a length L=16 cyclic prefix. The 4 subcarriers near N/2 are nulled. A digital modulation with M=64 is used in the modulation of sub-carriers. a. What is the subcarrier bandwidth? b. What is the length of the guard interval? c.