作者:陈旭文1, 刘桂雄2, 唐文明2
作者单位:1. 揭阳职业技术学院, 广东 揭阳 522051;
2. 华南理工大学, 广东 广州 510640
关键词:扩展收敛域;对数;区间压缩;FPGA
摘要:
针对经典自然对数坐标旋转数字计算机(coordinate rotation digital computer,CORDIC)算法在应用上存在问题,研究扩展收敛域任意对数CORDIC算法与FPGA实现。通过区间压缩方法,对收敛域外的数据进行转换,实现收敛域扩展至全收敛域,并应用换底公式扩展到任意底数的对数运算。仿真试验表明,采用15级流水线结构,以10为底的对数CORDIC运算最大时延小于17个时钟周期,最大计算误差为0.000 27。该算法应用于40 mm玻璃钢的超声检测中,其TCG回波图能有效抑制杂散波,提高信号的分辨力,运算速度比传统方法快,对超声相控仪器的开发具有应用价值。
Arbitrary logarithm CORDIC algorithm based on expansion convergence domain and FPGA implementation
CHEN Xuwen1, LIU Guixiong2, TANG Wenming2
1. Jieyang Vocational and Technical College, Jieyang 522051, China;
2. South China University of Technology, Guangzhou 510640, China
Abstract: Aiming at the problems of classic natural logarithm CORDIC algorithm on application, the convergence domain of extension arbitrary logarithm CORDIC algorithm and FPGA implementation is discussed. Using interval compression method to convert the extraterritorial data of convergence domain, the whole convergence domain is extended, and the arbitrary base logarithm operation is extended on the application of the soled formula. Simulation results show that using 15 stage pipeline structure, the maximum delay of logarithm CORDIC algorithm with base 10 is less than 17 clock cycles, and the maximum error is obtained 0.000 27. Ultrasonic testing on the 40 mm glass steel, the TCG echo can effectively suppress the spurious wave, improve the signal resolution, and the operation speed is faster than traditional methods, which has important application value on development of ultrasonic phased array instrument.
Keywords: extended convergence domain;logarithm;interval compression;FPGA
2015, 41(7): 108-111 收稿日期: 2015-2-8;收到修改稿日期: 2015-3-17
基金项目: 国家重大科学仪器设备开发专项(2013YQ230575)
作者简介: 陈旭文(1976-),男,广东揭阳市人,讲师,硕士,主要从事计算机应用研究与教学工作。
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