Resource-Efficient FPGA Architecture for Real-Time RFI Mitigation in Interferometric Radiometers.

Area of Science:

• Remote Sensing
• Electromagnetics
• Signal Processing

Background:

• L-band interferometric radiometers are vital for Earth observation, measuring soil moisture and ocean salinity.
• Increasing radio frequency interference (RFI) poses a significant challenge to the sensitive measurements required by these instruments.
• Maintaining a temperature resolution below 1 K is critical for accurate geophysical parameter retrieval.

Purpose of the Study:

• To present a hardware implementation of an advanced RFI detection and mitigation algorithm for L-band interferometric radiometers.
• To address the challenges posed by RFI in future L-band Earth observation missions.
• To optimize Field Programmable Gate Array (FPGA) resource utilization for real-time signal processing.

Main Methods:

• Implementation of a real-time RFI detection and mitigation algorithm using 1-bit quantized signals.
• Processing signals at 57.69375 MHz from multiple receivers.
• Employing time-frequency analysis and polarimetric detection techniques.
• Utilizing Field Programmable Gate Array (FPGA) optimization strategies, including overclocked cores and efficient resource management.

Main Results:

• Achieved real-time processing capabilities for interferometric radiometer signals.
• Demonstrated RFI detection probabilities exceeding 63% with false alarm rates below 1% in typical interference scenarios.
• Validated robust performance across various RFI conditions using synthetic datasets.

Conclusions:

• The developed hardware implementation effectively detects and mitigates RFI for L-band interferometric radiometers.
• The system's real-time processing and optimization strategies are suitable for future missions beyond SMOS.
• This RFI mitigation approach is essential for maintaining the integrity of Earth observation data.