SKA-Low had to tweak nature's sunflower spiral over a 125 MHz blind spot

The international team building the SKA-Low radio telescope in Australia found that a Vogel spiral antenna layout, inspired by sunflower seeds, creates a sensitivity drop at 125 MHz because one inter-antenna distance of 2.4 m repeats too often. Their fix is a Perturbed Vogel pattern with slightly shifted antenna positions.

• SKA-Low: 512 stations of 256 SKALA4.1 antennas each across 75 sq km, over 131,000 antennas total
• Frequency range 50–350 MHz, tested at AAVS2 and AAVS3 testbeds at Murchison
• Sensitivity drop at 125 MHz traced to a repeating 2.4 m spacing between antennas
• Solution is a Perturbed Vogel pattern with small position offsets