Joint optimization of single-carrier and multi-carrier DSL spectra

The loop plant can be optimized to provide significantly higher bit rates than currently provided, offering higher speeds that in some cases will even support digital entertainment video, without installing new remote terminals or repeaters. Algorithms for using measured crosstalk data to jointly optimize DSL performance have been recently published, and are based on finding the optimal transmit PSD in an iterative fashion. However, these algorithms can ensure joint optimization of homogenous DSL services only. In this paper, we present an iterative algorithm for jointly optimizing single-carrier and multi-carrier DSL services. In particular, we address the case of joint optimization of ADSL and G.shdsl. Simulations are run with many different crosstalk couplings for several scenarios of loop length and numbers of crosstalkers. Simulation results show that average bit rate increases of several hundred percent are commonly achieved on relatively long loops with these dynamic spectrum management (DSM) techniques.