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David M Le Vine

Publications and source records attributed to David M Le Vine.

20 records · Page 2

The scatter of obliquely incident plane waves from a corrugated conducting surface

A physical optics solution is presented for the scattering of place waves from a perfectly conducting corrugated surface in the case of waves incident from an arbitrary direction and for an observer far from the surface. This solution is used to compute the radar cross section of the surface in the case of backscatter from irregular (i. e. , stochastic) corrugations and is used to point out a correction to the literature on this problem. An interesting feature of the solution is the occurrence of singularities in the scattered fields. These singularities appear to be a manifestation of focussing by the surface at its "stationary" points. Whether or not the singularities occur in the solution depends on the manner in which one restricts the analysis to the far field.

David M Le Vine↗

Lessons Learned from SMAP Radiometer Pre-/Post-launch Calibration

The Soil Moisture Active Passive(SMAP) mission was launched on 31stJanuary 2015 in a 6 AM/ 6 PM sun-synchronous orbit at 685 km altitude to measure soil moisture and free/thaw globally [1]. The passive instrument of SMAP is a fully polarimetric L-band radiometer (1.4GHz) operating with a bandwidth of 24MHz. The radiometer uses a combination of noise-diodes and Dicke-loads for internal calibration with a design similar to that used by the Aquarius or Jason series radiometers[2,3].Pre-launch calibration activities had been performed since 2012on the engineering model of the radiometer. Post-launch calibration activities have been performed to fine-tune and validate the results from the pre-launch calibration. The major calibration activities and lessons learned in the past 8 years will be described in the following sections.

Jinzheng Peng↗