Yudhotomo, U. S., G. I. Gunadi, K. Khaerudin, and T. Siahaan. “2.22 GHz S-Band Helical Antenna Design for Earth Surveillance Lapan-Tubsat Data Acquisition in Indonesia Regional Security”. International Journal of Social Science Research and Review, Vol. 6, no. 1, Jan. 2023, pp. 447-56, doi:10.47814/ijssrr.v6i1.948.