T1e1.4/98-318r1

adapt to line changes. This document shows that: 1. the bit-swap protocol in ADSL standards is resilient to errors, even if entire acknowledgement commands are lost

T1e1.4/98-252

Several contributions to date, e.g. [1, 2, 3, 4] have proposed methods for reducing PAR at the output of the transmitter IFFT. The values of achievable PAR reduction, the complexity estimates and the algorithms described for these methods refer to these IFFT sample points. These values must be filtered and converted to continuous time prior to amplification, and thus a study of the PAR in the continuous domain is necessary. We show that if PAR reduction is done on these Nyquist rate samples, the PAR of the continuous time waveform can increase significantly, but if we extend the tone-reservation and tone-injection algorithms to reduce the PAR at twice the Nyquist rate, the continuous time PAR can be efficiently reduced by more than 4dB for a wide range of transmit filters. Moreover, for the toneinjection method we can extend our previous algorithms to include the effects of the transmit filter, which leads to PAR reductions of more than 5dB at the AFE input. NOTICE 1 This contributio..