Dynamic IUC for OFDMA Transmission By Hongbiao Zhang & Peter Wolff, Casa Systems In a cable plant, it is essential to manage upstream spectrum and mitigate the impact of interferences, especially for lower spectrum bands that are susceptible to various types of noise ingress.

The last major piece of the OFDMA puzzle is the interval usage codes (IUC). These are very similar to OFDM’s downstream profiles. Each IUC has a modulation and a pilot pattern and supports variable bit-loading.

IUC 13 is the base OUDP burst descriptor sent to the cable modem before it has completed registration with the CMTS. IUC 13 should be configured in the CMTS with a robust modulation such as 64-QAM or 128-QAM.

2021年4月27日 · Information “Produced or Provided” by the Entity (IPE) is evidence for the audit that is generated by the entity and used by the auditors to test a control. Information Used by the “Company or Entity” (IUC) is evidence that is used by the Company/Entity, in order to perform or execute their internal controls.

2020年4月1日 · Recommended Interval Usage Code (IUC) Based on the receive modulation error ratio (RxMER) values collected periodically during upstream probing, the CMTS finds among the existing IUCs up to two that provide the highest speed while having sufficient signal to noise ratio (SNR) margin for the CMTS to receive code words with acceptable error rates.

When a DOCSIS 3.1 modem first comes online and communicates with the CMTS using an upstream OFDMA channel, the CMTS will first set the modem’s OFDMA upstream data profile (OUDP) to IUC 13. This should be configured to be a low order modulation like 16-QAM so that it is resilient to any noise and ensures the modem will come online.

RxMER data and the IUC data is a powerful tool in understanding the performance of each of the node segments and the individual modems. This paper will discuss methods on how to analyze the upstream

The FEC T bytes can be increased on a long IUC from eight to nine when using 16-QAM. This table lists the recommended profiles, assuming four-tick minislots at 1.6 MHz, or two ticks at 3.2 MHz. IUC

2009年2月28日 · Request (IUC=1): This is the message sent by the cable modem when it has IP data to transmit. Initial Maintenance (IUC=3): These are the Range Requests sent by a cable modem to the CMTS in a contention window when a cable modem firsts starts to “range” with a CMTS (i.e. when a cable modem first registers).

We build our framework, called iUC, on top of the IITM model, which already provides soundness and flexibility while lacking sufficient usability. At the core of iUC is a single simple template for specifying essentially arbitrary protocols in a convenient, formally precise, and flexible way. We illustrate the main