DMT中一种格型结构算法的DSP实现分析

DMT(离散多音频)调制/解调是ADSL(不对称数字用户线)应用的标准传输技术.尽管DMT能达到比其它调制技术更高的速率,但其计算的复杂性也非常高,尤其是调制/解调核心程序FFT/IFFT的运算.因此,本文探索了一种特别适合DSP处理的时间递归(time-recursive)格型FFT/IFFT算法结构.该结构与其直接运算(N=256)相比仅需原来11%的乘法运算量和9%的加法运算量,从而使ADSL实时性、应用性大大提高.

The DSP Implementation and Analysis of the Lattice Architecture Algorithm In DMT

The discrete multitone (DMT) modulation/demodulation is the standard transmission technique in the application of asymmetric digital subscriber lines (ADSL).Although the DMT can achieve higher data rate compared with other modulation/demodulation schemes,its computational complexity is too high,especially to compute the modulation/demodulation kernel FFT/IFFT.Hence,a lattice algorithm based on the time recursive approach is presented,which is very suitable to run in programmable DSP.The algorithm requires only 11% number of multipliers and 9% number of adders compared with the direct implementation( N =256),so it improves greatly ADSL reality and applicability.