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Title: SDR Based Agile Radiometer with Onboard RFI Processing on a Small UAS
Passive microwave remote sensing plays an essential role in providing valuable information about the Earth’s surface, particularly for agriculture, water management, forestry, and other environmental fields. One of the key requirements for precision agricultural applications is the availability of field- scale high-resolution remote sensing data products. With the recent development of reliable unmanned aircraft systems (UAS), airborne deployment of remote sensing sensors has become more widespread to provide such products. With this in mind, we developed a UAS-based dual H-pol (hori- zontal) and V-pol (vertical) polarized radiometer operating in L-band (1400-1427 MHz). The custom dual-polarized an- tenna acquires surface emission response through a software- defined radio (SDR). This SDR-based system provides full control over the data acquisition parameters such as band- width, sampling frequency, and data size. Radio frequency interference (RFI) poses a significant challenge in radiometric measurements, requiring post-processing of the full-band radiometer data to identify and eliminate RFI-contaminated measurements, thus ensuring accurate Earth emission read- ings.. In this paper, we implemented near-real-time RFI detection onboard during the flight to accelerate the post- processing. The altitude and the speed of the UAS can be varied to achieve desired ground resolution for the measure- ment. This paper presents the full custom design and develop- ment of a lightweight SDR-based UAS-borne radiometer for precision agriculture. Additionally, we introduce the concept of an agile radiometer implemented from a small UAS that can serve as a testbed for both current and future spaceborne missions.  more » « less
Award ID(s):
2030291
PAR ID:
10565898
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IEEE
Date Published:
ISSN:
2153-7003
ISBN:
979-8-3503-2010-7
Page Range / eLocation ID:
4368 to 4371
Subject(s) / Keyword(s):
SDR, Radiometer RFI UAS microwave L-band b210 dual-polarized passive coexistence soil moisture
Format(s):
Medium: X
Location:
Pasadena, CA, USA
Sponsoring Org:
National Science Foundation
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