Dynamic tunable notch filters for the Antarctic Impulsive Transient Antenna (ANITA)

• Main Authors: Allison, P, Banerjee, O, Beatty, JJ, Connolly, A, Deaconu, C, Gordon, J, Gorham, PW, Kovacevich, M, Miki, C, Oberla, E, Roberts, J, Rotter, B, Stafford, S, Tatem, K, Batten, L, Belov, K, Besson, DZ, Binns, WR, Bugaev, V, Cao, P, Chen, C, Chen, P, Chen, Y, Clem, JM, Cremonesi, L, Dailey, B, Dowkontt, PF, Hsu, S, Huang, J, Hupe, R, Israel, MH, Kowalski, J, Lam, J, Learned, JG, Liewer, KM, Liu, TC, Ludwig, AB, Matsuno, S, Mulrey, K, Nam, J, Nichol, RJ, Novikov, A, Prohira, S, Rauch, BF, Ripa, J, Romero-Wolf, A, Russell, J, Saltzberg, D, Seckel, D, Shiao, J, Stockham, J, Stockham, M, Strutt, B, Varner, GS, Vieregg, AG, Wang, S, Wissel, SA, Wu, F, Young, R
• Format: Article in Journal/Newspaper
• Language: English
• Published: ELSEVIER SCIENCE BV 2018
• Subjects: Neutrino radio detection; Ultra-high-energy; Notch filtering; Military communications satellites; Antarctic; The Antarctic; Antarc*
• Online Access: https://discovery.ucl.ac.uk/id/eprint/10056759/1/Cremonesi_1709.04536.pdf; https://discovery.ucl.ac.uk/id/eprint/10056759/

The Antarctic Impulsive Transient Antenna (ANITA) is a NASA longduration balloon experiment with the primary goal of detecting ultra-highenergy (> 1018 eV) neutrinos via the Askaryan Effect. The fourth ANITA mission, ANITA-IV, recently flew from Dec 2 to Dec 29, 2016. For the first time, the Tunable Universal Filter Frontend (TUFF) boards were deployed for mitigation of narrow-band, anthropogenic noise with tunable, switchable notch filters. The TUFF boards also performed second-stage amplification by approximately 45 dB to boost the ∼ µV-level radio frequency (RF) signals to ∼ mV-level for digitization, and supplied power via bias tees to the first-stage, antenna-mounted amplifiers. The other major change in signal processing in ANITA-IV is the resurrection of the 90◦ hybrids deployed previously in ANITA-I, in the trigger system, although in this paper we focus on the TUFF boards. During the ANITA-IV mission, the TUFF boards were successfully operated throughout the flight. They contributed to a factor of 2.8 higher total instrument livetime on average in ANITA-IV compared to ANITAIII due to reduction of narrow-band, anthropogenic noise before a trigger decision is made.