2008 IEEE International Geoscience & Remote Sensing Symposium
July 6-11, 2008 | Boston, Massachusetts, U.S.A.

HD-11: Introduction to Microwave Radiometry

Sunday Morning, July 6, 08:30 - 12:30

Presented by

R. Vincent Leslie, MIT Lincoln Laboratory and Michael J. Schwartz, Microwave Atmospheric Science Group, NASA JPL

Abstract

This tutorial will introduce microwave radiometry, which is the measurement of electromagnetic energy in the microwave and millimeter portion of the Radio Frequency spectrum. Microwave radiometry has played an important role for decades in weather forecasting and environmental remote sensing. The tutorial will start with a history of passive microwave sensors and the applications of those sensors. The radiometer is the fundamental microwave sensor, and this tutorial will review its general design and technology. The components include the antenna that collects the electromagnetic energy and the receiver that converts the energy into a signal (i.e., voltage). The next topic will be the important aspect of calibrating the radiometer, which converts the ambiguous units of voltage into useful units of power (i.e., brightness temperature). To further understand the functionality of microwave radiometry, this tutorial will cover the physics starting with Planck's Law and basic radiative transfer theory and move on to the interaction of the electromagnetic radiation with the atmosphere, surface, and weather phenomena. Using these fundamental blocks, the instrument forward model will give insight into the applications of microwave radiometry. In particular, the forward model sets the theory for retrieving the atmospheric state at the time of the radiometric measurement. Many applications require the ability to simulate the radiometric measurements, and the fundamentals of simulation will be discussed. The tutorial will conclude with a more in-depth look at the applications introduced in the beginning and investigate the future of microwave radiometry.

Outline

  1. Introduction
    1. Applications
    2. History
  2. Radiometer
    1. Antennas
    2. Receivers
    3. Calibration
    4. Data Processing
    5. Characteristics
  3. Physics
    1. Planck’s Law and Blackbodies
    2. Atmospheric microwave absorption
    3. Nonscattering Radiative Transfer
    4. Cloud and surface effects
    5. Instrument forward model
    6. Retrieval of atmospheric state
    7. Zeeman-splitting and polarized radiative transfer
  4. Summary
    1. Applications Revisited
    2. Future Sensors

Speaker Biographies

Dr. R. Vincent Leslie is employed at MIT Lincoln Laboratory and works with microwave sensors on the upcoming National Polar-orbiting Operational Environmental Satellite System (NPOESS) and the legacy Polar Operational Environmental Satellite (POES). Dr. Leslie graduated from MIT in 2004 with a Doctorate of Science from the Remote Sensing and Estimation Group (RSEG) led by Professor David H. Staelin. Dr. Leslie’s thesis work was on the NPOESS Aircraft Sounder Testbed, which is an airborne microwave sensor deployed by NPOESS as a risk-reduction effort.

Dr. Michael J. Schwartz is a member of the Microwave Atmospheric Science Group at the NASA Jet Propulsion Laboratory. He is responsible for temperature and geopotential-height products from the Microwave Limb Sounder (MLS) on the EOS Aura satellite and has adapted non-scattering, polarized radiative transfer algorithms for modeling of MLS radiances near Zeeman-split oxygen spectral lines. Dr. Schwartz did his thesis work in the Remote Sensing and Estimation Group at MIT led by Prof. David H. Staelin, receiving his Ph.D. in Physics in 1999.