Non-iterative bit-loading algorithm for ADSL-type DMT applications

The authors propose a solution to the hit-loading problem for discrete multitone (DM1) modulation on digital subscriber loops (DSL). which involves less complex calculations than the existing algorithms. An optimal loading algorithm is presented and evaluated where the average bit error rate (BER) of the DMT is minimised for given total bit-rate and overall available power constraints. For reasons of simplicity, bit and power allocations are optimised separately. Unlike existing algorithms, the proposed algorithm is non-iterative, and thus requires fewer complex calculations. Computer simulation results, using the classical carrier serving area (CSA) lines in an ADSL environment, show that, in addition to having low computational complexity, the proposed method is slightly more efficient than existing algorithms.