Multi-Beam Passive Microwave Radiometer Design using Multi-Path Cross Correlation Radiometry

Orbital Micro Systems, Inc. (OMS) proposes “Multipath Cross-Correlation Radiometry” (MXCR) as a new means of continuous multi-beam radiometer “self-calibration” that will obviate the need for conventional switched calibration looks, whether from internal noise sources or external blackbody targets. It will simultaneously implement multiple independently radiometric antenna beams that provide a simultaneously sampled push broom imaging capability, thus reducing or eliminating mechanical scan requirements. Importantly, MXCR will facilitate high spectral resolution (0.1-1 MHz bandwidth channel) radiometry over wide (multi-GHz) bands with rejection of out-of-band radio frequency interference due to it’s a unique path gain cancelling inversion algorithm that is unavailable using conventional single-path or two-path correlation radiometry. As a result of this algorithm, 1/f gain fluctuations are entirely cancelled out of the inversion process. This specific study address the implementation of several simultaneous radiometer antenna beams using FPGA-based MXCR detection architecture.