| 摘要: |
| 为了提高线性调频连续波(Linear Frequency Modulation Continuous Wave，LFMCW)雷达的测距精度，一般采用稳定性能好、计算量小的Quinn算法。但在低信噪比、频率偏差位于量化频谱附近时，Quinn算法的估计误差很大。针对Quinn算法的缺陷，提出了一种改进的Quinn算法，该算法引入频率偏差因子，把频率偏差先平移到量化频率中间，利用Quinn算法在频率偏差位于量化频谱中间获取高精度测距的优点，提高LFMCW雷达的测距精度。仿真结果表明，改进的Quinn算法具有很好的抗噪声性能，频率估计均方根误差接近克拉美罗下限（Cramer-Rao Low Bound，CRLB），能够满足LFMCW对测距精度的需求。 |
| 关键词: 线性调频连续波雷达 测距精度 Quinn算法 频率偏差 |
| DOI：10.3969/j.issn.1672-2337.2018.05.001 |
| 分类号:TN958.94 |
| 基金项目:国家自然科学基金(No.61771083，61704015)； 长江学者和创新团队发展计划(No.IRT1299)； 重庆市科委重点实验室专项经费； 重庆市基础与前沿研究计划项目(No.cstc2015jcyjBX0065)； 重庆市高校优秀成果转化资助项目(No.KJZH17117) |
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| An Improved Quinn Algorithm for Improving the LFMCW Radar Ranging Accuracy |
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LI Lingxia，JIA Shuai，XIE Liangbo，JIANG Zhi
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Chongqing Key Lab of Mobile Communications Technology，Chongqing University of Posts and Telecommunications，Chongqing 400065，China
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| Abstract: |
| In order to improve the ranging accuracy of LFMCW radar，Quinn algorithm has been adopted due to its good stability and low computational complexity.However，the ranging accuracy of Quinn algorithm will decrease when the signal to noise ratio is low and the frequency deviation locates nearby the quantization spectrum.To solve this issue，an improved Quinn algorithm is proposed，which can achieve the high ranging accuracy when the frequency deviation locates in the middle of the quantized spectrum.Utilizing the advantage of the Quinn algorithm，the proposed algorithm uses a frequency deviation factor to shift the frequency deviation to the middle of the quantization frequency to increase the ranging accuracy.Simulation results show that the improved Quinn algorithm has high noise immunity，and the normalized mean square error of frequency estimation is close to CRLB，which can satisfy the ranging accuracy requirement of LFMCW. |
| Key words: LFMCW radar ranging accuracy Quinn algorithm frequency deviation |
