发表机构
Delft University of Technology; Robin Radar Systems（代尔夫特理工大学; Robin雷达系统公司）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出一种通过改变FMCW啁啾间等待时间实现对数周期慢时间采样，结合复高斯过程最大似然估计，在短驻留天气雷达中实现无模糊多普勒速度谱重建，实验验证了非周期采样在扩展域分支识别和谱宽估计上的优势。
AI 中文摘要
本文解决了短驻留天气雷达测量中的快速多普勒反折叠问题。所提出的方法通过仅改变频率调制连续波（FMCW）啁啾之间的等待时间，实现了对数周期慢时间设计。快速时间波形、带宽和距离处理链保持不变，而采集改变了多普勒模糊结构。我们为分布式天气谱制定了一种新颖的矩空间模糊函数。该函数在平均多普勒速度和谱宽上联合度量统计模糊性，并通过期望相对似然表示竞争性旁瓣。一种复高斯过程（CGP）最大似然估计器从测量的非周期样本中重建谱。一种确定性盆地选择和优化策略加速了相同的CGP似然计算，而无需定义不同的统计估计器。真实降水测量在扩展搜索域上确立了中心分支的稳定性。使用64次慢时间扫描，我们比较了三种采集方式及其相关估计器。周期数据通过离散傅里叶变换（DFT）和参数谱估计（PSE）处理，对数周期数据通过非均匀离散傅里叶变换（NUDFT）和CGP处理，交错数据通过速度差和CGP估计器处理。当驻留时间减少到32次扫描时，差异变得更加明显。结果表明，非周期时间采样能够实现扩展域分支识别，而不会降低谱宽估计的性能。
英文摘要
The problem of fast Doppler counter-aliasing for short-dwell weather-radar measurements is addressed. The proposed approach realizes a log-periodic slow-time design by changing only the waiting time between otherwise unchanged frequency-modulated continuous-wave (FMCW) chirps. The fast-time waveform, bandwidth, and range-processing chain are preserved while the acquisition changes the Doppler ambiguity structure. We formulate a novel moment-space ambiguity function for distributed weather spectra. It measures statistical ambiguity jointly in mean Doppler velocity and spectral width and expresses the competing sidelobes through their expected relative likelihood. A complex Gaussian process (CGP) maximum-likelihood estimator reconstructs the spectrum from the measured aperiodic samples. A deterministic basin-selection and optimization strategy accelerates the same CGP likelihood without defining a different statistical estimator. Real precipitation measurements establish central-branch stability over an extended search domain. Using 64 slow-time sweeps, we compare three acquisitions and their associated estimators. Periodic data are processed by the discrete Fourier transform (DFT) and parametric spectral estimation (PSE), log-periodic data by the nonuniform discrete Fourier transform (NUDFT) and CGP, and staggered data by velocity-difference and CGP estimators. The differences become more pronounced when the dwell is reduced to 32 sweeps. The results show that aperiodic time sampling enables extended-domain branch identification without degrading spectral-width estimation.
Comments24 pages, 14 figures, 1 table
