计算机与现代化 ›› 2013, Vol. 218 ›› Issue (10): 167-171.doi: 10.3969/j.issn.10062475.2013.10.041

• 应用与开发 • 上一篇    下一篇

DDS中ROM存储的线性分层插值压缩方法

熊巍   

  1. 江西省计算技术研究所,江西南昌330002
  • 收稿日期:2013-07-23 修回日期:1900-01-01 出版日期:2013-10-26 发布日期:2013-10-26

Hierachical Linear Interpolation Approach of ROM Compressionin Direct Digital Frequency Synthesizer

XIONG Wei   

  1. Jiangxi Institute of Computing Technology, Nanchang 330002, China
  • Received:2013-07-23 Revised:1900-01-01 Online:2013-10-26 Published:2013-10-26

摘要: 在直接数字频率合成器(Direct Digital Frequency Synthesizer, DDS)中,传统ROM存储表的正弦函数幅度压缩法为了达到高压缩率,通常采用较为复杂的正弦近似函数,增加了硬件电路的复杂度。本文提出一种线性分层插值的ROM表压缩方法,通过分层、分段线性插值近似,可以显著减少相位点幅度的量化比特数,同时各层可以共用同一个插值和重建电路,使得硬件的复杂度显著降低。理论分析和仿真结果表明,本文提出的ROM表压缩方法在不显著增加硬件电路复杂度的情况下,可以有效提高ROM表的压缩比。

关键词: 直接数字频率合成, 压缩比, 插值函数, 存储压缩

Abstract: Complex approximate functions are often used in traditional sine amplitude compression approach for ROM compression in direct digital frequency synthesizer to achieve high compression rate. This paper proposes a new hierachical linear interpolation approach for ROM compression and phase-to-sine amplitude conversion of sinusoid output DDS. Experimental results show that the proposed approach can achieve a higher compression rate with equal spectral performances and simpler hardware structure than most of the previous works.

Key words: direct digital frequency synthesis, compression ratio, interpolation function, storage compression

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