ABSTRAKSI: Antena Antena Caturcula Chebyshev Unidireksional (SN.MT 0924-CCU-0709) ini dirancang dengan tujuan : 1. Menyediakan prototype antena unidireksional berpita sangat lebar, supaya dapat digunakan oleh beberapa operator secara gotong royong untuk menghemat menara serta lahannya. 2. Membuktikan hipotesis dari pembimbing I bahwa antena adalah pemadan impedansi antara ruang propagasi dengan saluran radio. Spesifikasi yang harus dipenuhi adalah : frekuensi kerja 0,3 GHz – 3,0 GHz dalam VSWR maksimal 1,5 :1 pada terminal 50 Ω anbalan, gain ≥ 2,14 dBi, unidireksional, berpolaritas linier. Antena ini harus dibangun dengan saluran strip kembar sejajar, berdasar transformator chebyshev, untuk digunakan di udara atau hampa; menggunakan balun jenis monopol segitiga supaya berpita lebar tetapi tanpa lilitan di toroida. Dengan kaidah saluran strip sejajar diperoleh konstruksi (susunan bahan dan ukuran masing-masing) sebagai berikut : N = 3,574 ≈ 4 tingkat, εr1 = 2,217 (puzzle) l1 = 30,52 mm, εr2 = 1,908 (kalender ITT) l2 = 32,90 mm, εr3 = 1,643 (kardus) l3 = 35,45 mm, εr4 = 1,025 (Styrofoam dan udara) l4 = 44,88 mm. Menggunakan strip tembaga sejajar w = 3,44 mm x s = 20 mm. Balun monopol segitiga dibangun dari tembaga bersudut konik 900 tinggi ≈ s = 20 mm, berterminal ZT = 50 Ω anbalan. Melalui pengujian spesifikasi di pekarangan IT Telkom didapat hasil sebagai berikut: di dalam VSWR ≤ 1,5 teryata frekuensi kerja 901,2 MHz - 2476,2 MHz dan dalam VSWR ≤ 2 teryata frekuensi kerja 664,4 MHz – 2893,5 MHz pada terminal 50 Ω anbalan, gain = 7,85 dBi pada frekuensi 1650 MHz dan gain = 8,03 dBi pada frekuensi 2082 MHz, berpolarisasi ellips. Untuk mencapai fekuensi kerja spesifikasi sebesar 0,3 GHz – 3,0 GHz dalam VSWR ≤ 1,5, disarankan spasi antar strip diperlebar sehingga h ≈ s = (λmin / 2) = 5 cm atau culanya terhubung kapasitif dengan monotriangularnya.Kata Kunci : Antena Caturcula, Penyepadan Chebyshev, UnidireksionalABSTRACT: This Chebyshev Unidirectional Caturcula Antenna (SN.MT 0924-CCU-0709) is designed and implemented with two purposes: 1. To make very wideband unidirectional antenna available, in order can be used by several operators jointly to economize tower and area. 2. To prove the hypothesis from first advisor’s which is told antenna is matching device between propagation space and radio transmission lines. Specification that must be fulfilled is: working frequency 0.3 GHz – 3.0 GHz in VSWR ≤ 1.5 with 50Ω unbalance; gain ≥ 2.14 dBi, unidirectional pattern, and with linear polarization. This antenna must be built with parallel twin conductor, and with chebyshev transformator to be used in air or vacuum; use England triangular type balun to produce wideband frequency. With parallel twin strip principle, constructions—material composition and each dimension—are obtained, they are: N = 3.574 ≈ 4 grade, εr1 = 2.217 (puzzle rubber) l1 = 30.52 mm, εr2 = 1.908 (ITT calendar) l2 = 32.90 mm, εr3 = 1.643 (cardboard) l3 = 35.45 mm, εr4 = 1.025 (Styrofoam and air) l4 = 44.88 mm. Use parallel copper strip with width (w) 3.44mm x length (l) 170mm, space (s) 20mm (chosen). Triangle monopole balun is built from copper with 90o angle, height (s) = 20mm, and with 50Ω unbalance terminal impedance. From measurement of these specification in IT Telkom yard, some results are obtained, they are: VSWR ≤ 1.5:1 with operation frequency from 901.2 MHz - 2476.2 MHz and at VSWR ≤ 2:1 with operation frequency from 664.4 MHz – 2893.5 MHz at unbalance 50Ω terminal, gain = 7.85 dBi at 1650 MHz and gain = 8.03 dBi at 2082 MHz, with unidirectional radiation pattern, and ellipse polarization. To set the operational frequency from 0.3 GHz – 3.0 GHz at VSWR ≤ 1.5:1 is suggested to make the space h ≈ s = (λmin / 2) = 5 cm or between strip and its monotriangular also be matched to be capacitive coupling.Keyword: caturcula antenna, Chebyshev transformer, Unidirectional