An Advanced Multi-Frequency Radar for Atmospheric Research

用于大气研究的先进多频雷达

• 批准号: 0116272
• 负责人: Stephen Frasier
• 金额: $ 100万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0116272&HistoricalAwards=false
• 关键词: Advanced; Multi; Frequency; Radar; Atmospheric

This is a Major Research Instrumentation award that supports the development of a portable, three-wavelength scanning radar designed for meteorological research. Called the Advanced Multi-Frequency Radar (AMFR), it consists of a single antenna capable of transmitting and receiving frequencies in the Ku-band (13 GHZ), Ka-band (33 GHz), and W-band (95 GHz). (These frequencies correspond respectively to wavelengths of 2.2, 0.91, and 0.32 cm.) Each of the three radar systems will be capable of both Doppler and polarization measurements. The PI has already developed a dual-wavelength radar called the Cloud Profiling Radar System (CPRS), which operates at 0.9 and 0.3 cm. This award enables the addition of the third radar having 2.2 cm wavelength, the construction of a new antenna, and improvement of the sensitivity of the existing systems at 0.9 and 0.3 cm. A unique feature of the radar is a system of feeds designed to insure that the single antenna produces collocated, matched beams for the three wavelengths. Measurements at all wavelengths will thus be from the same volume of cloud. The AMFR will be highly portable and relatively inexpensive to deploy. Applications will be primarily to cloud microphysics. Initial emphasis will be on layer clouds and precipitation processes in winter storms. The radar will be able to detect some precipitation-free clouds, at least at the shorter wavelengths. Moreover, rain and snow, when present, give different signals at the three receivers because the polarization characteristics of precipitation and the deviations from Rayleigh scattering both depend on wavelength. These signals can be employed in various ways to distinguish rain from snow and to give information on the shape of ice-phase precipitation particles, the drop-size distribution in rain, and the variation of these quantities with height and time. Measurements of this kind will give new insight on the formation and evolution of precipitation, contributing fundamentally to cloud physics and providing information needed to improve the treatment of precipitation in mesoscale and climate models.

这是一项重大研究仪器奖，旨在支持为气象研究设计的便携式三波长扫描雷达的开发。 它被称为高级多频雷达（AMFR），由一个能够发射和接收Ku波段（13 GHz）、Ka波段（33 GHz）和W波段（95 GHz）频率的单一天线组成。 （这些频率分别对应于2.2、0.91和0.32 cm的波长。） 三个雷达系统中的每一个都将能够进行多普勒和偏振测量。 PI已经开发了一种称为云廓线雷达系统（CPRS）的双波长雷达，其工作波长为0.9和0.3厘米。 该合同使第三部雷达的波长增加到2.2厘米，建造新的天线，并提高现有系统在0.9和0.3厘米的灵敏度。 该雷达的一个独特之处是设计了一个馈电系统，以确保单个天线为三个波长产生并置的匹配波束。 因此，所有波长的测量将来自相同体积的云。 AMFR将是高度便携的，部署起来相对便宜。 应用将主要是云微物理学。 最初的重点将放在冬季风暴中的层状云和降水过程上。 该雷达将能够探测到一些无降水云，至少在较短的波长。 此外，雨和雪，当存在时，在三个接收器给出不同的信号，因为降水的偏振特性和瑞利散射的偏差都取决于波长。 这些信号可以以各种方式用于区分雨和雪，并提供有关冰相降水粒子形状、雨中水滴尺寸分布以及这些量随高度和时间的变化的信息。 这种测量将使人们对降水的形成和演变有新的认识，从根本上促进云物理学，并提供必要的信息，以改进中尺度和气候模式中对降水的处理。