Parametric Design of a Microwave Radiometer for Land Surface Temperature Retrieval from Moon-Based Earth Observation Platform

Linan Yuan,Jingjuan Liao

doi:10.3390/rs12244110

Abstract

Increasing attention is being paid to the monitoring of global change, and remote sensing is an important means for acquiring global observation data. Due to the limitations of the orbital altitude, technological level, observation platform stability and design life of artificial satellites, spaceborne Earth observation platforms cannot quickly obtain global data. The Moon-based Earth observation (MEO) platform has unique advantages, including a wide observation range, short revisit period, large viewing angle and spatial resolution; thus, it provides a new observation method for quickly obtaining global Earth observation data. At present, the MEO platform has not yet entered the actual development stage, and the relevant parameters of the microwave sensors have not been determined. In this work, to explore whether a microwave radiometer is suitable for the MEO platform, the land surface temperature (LST) distribution at different times is estimated and the design parameters of the Moon-based microwave radiometer (MBMR) are analyzed based on the LST retrieval. Results show that the antenna aperture size of a Moon-based microwave radiometer is suitable for 120 m, and the bands include 18.7, 23.8, 36.5 and 89.0 GHz, each with horizontal and vertical polarization. Moreover, the optimal value of other parameters, such as the half-power beam width, spatial resolution, integration time of the radiometer system, temperature sensitivity, scan angle and antenna pattern simulations are also determined.

Highlights

As industrial development continues, a series of unprecedented global environmental problems are confronting mankind in the 21st century—including the greenhouse effect, global climate warming, glaciers melt, sea level rise, land desertification, water resource shortages, etc
The results show that the average errors of the land surface temperature (LST) estimations of the six frequencies are 8.10, 8.50, 7.49, 5.45, 7.09 and 7.80 K, while the root mean square errors (RMSEs) are 4.21, 3.59, 3.96, 4.29, 4.28 and 4.18 K, respectively
From the comparison of the spatial resolution, it can be seen that the image quality of the Moon-based microwave radiometer (MBMR) is the same as the existing Advanced Microwave Scanning Radiometer (AMSR-E) and Microwave Radiation Imager (MWRI), which can be applicable for LST retrieval application

Summary

Introduction

A series of unprecedented global environmental problems are confronting mankind in the 21st century—including the greenhouse effect, global climate warming, glaciers melt, sea level rise, land desertification, water resource shortages, etc. Spaceborne Earth observation platforms, such as polar orbit satellites, geostationary satellites and the Deep Space Climate Observatory (DSCOVR), have many limitations in rapidly acquiring global-scale data. The geostationary orbit satellites have poor performance in high-latitude areas and cannot observe the polar areas, they have a high time resolution [1,2]. The DSCOVR, located at the Sun–Earth L1 point, has a low spatial resolution and cannot achieve global-scale observations of the Earth at night [3,4]. Due to the low orbital altitude, limited technological level, poor observation platform stability and limited design life, artificial satellites cannot continuously obtain measurements with high time resolution and global scale coverage. The development of an advanced platform to acquire real-time, comprehensive and accurate global Earth observation data is desirable

Methods

Results

Discussion

Conclusion