DOCSIS-CMTS-CM-US-OFDMA is an auxiliary schema that defines the CM's status information for OFDMA upstream channels. Revision History: 3.5.1-B.2 Per ECN CCAP-OSSIv3.1-N-20.2110-2: Updates definitions for MeanRxMer, StdDevRxMer, and ThresholdRxMerValue to clarify these values are reported in units Hundredth dB, per ECN CCAP-OSSIv3.1-N-20.2110-2. 3.5.1-B.1 Initial version. DOCSIS 3.1 CCAP Operations Support System Interface Specification CCAP-OSSIv3.1-N-15.1390-2 This attribute is the lower of the CCAP’s maximum supported upstream frequency and the CM’s maximum supported upstream frequency. It indicates the highest upstream frequency the CCAP can use to receive signals from this CM taking into account the capabilities of both devices. This attribute is the total received power in a specified OFDMA channel, normalized to power in a 1.6 MHz bandwidth, at the RF input port of the CMTS for a given CM. This attribute is the mean of the dB values of the RxMER measurements of all active subcarriers. The mean is computed directly on the dB values as follows: Mean = sum of (RxMER dB values) / number of RxMER values MeanRxMer is reported in units Hundredth dB. This attribute is the standard deviation of the dB values of the RxMER measurements of all active subcarriers. The standard deviation is computed directly on the dB values as follows: StdDev = sqrt(sum of (RxMER dB values - RxMER_mean)^2 / number of RxMER values) StdDevRxMer is reported in units Hundredth dB. This attribute specifies the percentile (such as 2nd percentile or 5th percentile) of all active subcarriers in an OFDM channel at which the ThresholdRxMerValue occurs. That is, (Percentile) % of the subcarriers have RxMER less than or equal to the ThresholdRxMerValue. This attribute is the RxMER value corresponding to the specified RxMerThreshold percentile value. The CCAP sorts the subcarriers in ascending order of RxMER, resulting in a post-sorting subcarrier index ranging from 1 to the number of active subcarriers. If the percentile value corresponds to a non-integer post-sorting subcarrier index, the post-sorting index is truncated (floor function is applied); that is, the post-sorting index is selected which is the greatest integer less than or equal to the corresponding percentile value. For example, if there are 3677 active subcarriers and the 2nd percentile is specified, the CCAP computes floor(3677*0.02) = 73. That is, the RxMER value of the 73rd subcarrier in the sorted list is associated with the 2nd percentile. ThresholdRxMerValue is reported in units Hundredth dB, but is only accurate to a quarter dB. This attribute is the frequency in Hz of the highest-frequency subcarrier having RxMER = ThresholdRxMer value.