Measured Spectral Compatibility of T1.413 Fdd Psd Mask Compliant Non-stationary Service with Dmt

This paper presents some measurements supporting the spectral compatibililty of a T1.413 FDD PSD mask compliant non-stationary service with a DMT service that is using bit swapping. EtherLoop technology modems use a Spectrum Manager function to monitor the line between bursts, and upon detecting significant coupling with an ADSL type service, switch to a safe mode of operation [1]. This safe mode of operation imposes a maximum output power limit for each EtherLoop baud rate that conforms to the T1.413 Issue 2 FDD PSD mask [2]. First, this paper points out a possible error in the test setup used in “Selected Measurement on Non-Stationary and Stationary Crosstalk Effects upon FDM ADSL” [3]. Next this paper presents test data which confirm that non-stationary services whose output power exceeds the T1.413 FDD PSD mask [2] can impact a DMT system that uses bit swapping. Finally, this paper presents test data which show that a non-stationary service whose power levels conform to the T1.413 FDD PSD mask [2] has no negative impact on a DMT system that uses bit swapping.