关键词: 非正交多重调制, 离散多音调制, 非对称数字用户环路（ADSL）, 甚高速数字用户环路（VDSL）

Abstract: The Non-orthogonal Multi-modulation Technique（NMT） is a novel modulation technology in which the orthogonality restrictions have been broken through.For validating the feasibility of NMT and providing the evidences of using the new modulation method on ADSL and VDSL，the contrastive computer simulations between NMT and DMT on the ADSL and VDSL loops are conducted.In this paper the coding structures of NMT and DMT are briefly described firstly，and then the technical issues of engineering applications of NMT，such as sub-wave interference and wave form pre-processing，Peak to Average Ratio（PAR），and ill-conditioned equations are interpreted.The feasibility of NMT and the advantages against DMT are verified by the computer simulations，and the transmission efficiency increases by 15% at least.

Key words: Non-orthogonal Multi-modulation Technology（NMT）, Discrete Multi-Tone（DMT）, Asymmetric Digital Subscriber Loop（ADSL）, Very-high-bit-rate Digital Subscriber Loop（VDSL）