J4 ›› 2013, Vol. 40 ›› Issue (6): 62-66.doi: 10.3969/j.issn.1001-2400.2013.06.011

• 研究论文 • 上一篇    下一篇

一种4路内插CORDIC的14位吉赫兹DDS IP核

刘马良;朱樟明;郭旭龙;杨银堂   

  1. (西安电子科技大学 微电子学院,陕西 西安  710071)
  • 收稿日期:2013-04-09 出版日期:2013-12-20 发布日期:2014-01-10
  • 作者简介:刘马良(1985-),男,西安电子科技大学博士研究生,E-mail: liumalianghy@163.com.
  • 基金资助:

    国家863资助项目(2012AA012302,2013AA014103)

4-channel-interpolated 14-bit high speed CORDIC DDS IP core

LIU Maliang;ZHU Zhangming;GUO Xulong;YANG Yintang   

  1. (School of Microelectronic, Xidian Univ., Xi'an  710071, China)
  • Received:2013-04-09 Online:2013-12-20 Published:2014-01-10

摘要:

直接数字频率合成器由于具有快速的频率转换时间和极高的频率分辨率,已得到了广泛的应用,但输出带宽较窄和杂散抑制较差一直是制约直接数字频率合成器输出信号质量的关键因素.基于改进的CORDIC相位幅度映射技术,采用4级流水线结构的相位累加器,设计了一种4路内插CORDIC结构的14位高速直接数字频率合成器 IP核.与传统单路CORDIC结构相比,时钟采样频率是原来的4倍,能有效提高输出信号的无杂散动态范围,并降低电路的复杂度和面积.验证结果表明,当采样时钟频率为1GHz、频率分辨率为0.23Hz、输出频率为82MHz时,无杂散动态范围为86.7dBc,基于0.18μm 1P6M CMOS工艺所实现的IP核有效面积为1.33mm2,能嵌入式应用于高精度宽频雷达、通讯系统的系统芯片.

关键词: 直接数字频率合成器, 坐标旋转机算法, 时钟内插, 改进相位幅度映射, CMOS

Abstract:

The direct digital frequency synthesizer (DDS) has been widely used because of the advantages of less frequency hopping time and fine frequency discrimination. But the disadvantages of narrowband and poor SFDR performance limit the quality of the DDS output signal. Based on the improved phase to sine-amplitude mapping technology, this paper presents a 4-channel-interpolated 14-bit high speed CORDIC DDS IP core with a 4-stage pipelined phase accumulator. Compared with the traditional CORDIC structure, the sample rate is four times higher, and the complexity and area of the circuit are reduced. The test results indicate that when the sample clock frequency is 1GHz and the frequency resolution is 0.23Hz, the output frequency is 82MHz with a SFDR of 86.7dB. Based on the 0.18μm 1P6M CMOS process, the effective area of the IP core is 1.33mm2. The DDS presented in this paper can be used in system chips of the high accuracy wide band radar and communication system as embedded application.

Key words: direct digital frequency synthesizer, coordinate rotation digital computer, clock interpolation, improved for phase to sine-amplitude mapping, complementary metal oxide semiconductor

中图分类号: 

  • TN402