An increasing number of experiments are targeting GHz bandwidth impulsive radiation induced by high energy neutrinos in ice or high energy cosmic ray air showers. Beamforming triggers improve detection prospects at low signal-to-noise ratio (SNR), since effective SNR scales as the square root of the number of phased array antennas in a coherent sum. However, this also brings high technological requirements with an increasing number of narrower beams required, while sub-nanosecond synchronisation must be maintained across the antennas summed in each beam. A prototype digital beamforming trigger is developed using Radio-frequency-systems-on-a-chip (RFSoCs), an adaptable radio platform leveraging the advantages of Field Programmable Gate Arrays (FPGAs). Findings are presented including power consumption, number of beams that can be formed per chip, trade-offs between resource usage and trigger efficiency and using programmable logic for flexible digital filtering capabilities.
FPGA; beamforming trigger; radio; ultra high energy neutrinos; digital signal processing; Askaryan effect; low-threshold trigger; coherent sum; interferometric phased array
|Subcategory||Experimental Methods & Instrumentation|