CONFORMAL ARRAY ANTENNA FOR TELEMETRY RADIO AND GPS L1 APPLICATIONS ON SOUNDING ROCKET

• Main Author: Benedikto Renwarin, Rezki
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80370
• Institution: Institut Teknologi Bandung

The design of the antenna on the sounding rocket needs to fulfill challenges of the mechanical and electrical fields. From a mechanical perspective, an antenna is needed that is thin, light, compact, vibration resistant and can be mounted on the rocket body. From an electrical perspective, an antenna is needed that can produce multi-band or wideband bandwidth and suf icient gain, impedance characteristics that are easy to adjust, polarization that suits the needs and an omnidirectional radiation pattern. This research shows the design and characteristics of a conformal array antenna for radio telemetry and GPS L1 applications on sounding rocket. The radio telemetry antenna consists of a 1 x 2 circular array that produces dual-band with center frequencies of 0.91 GHz and 2.45 GHz and suppression of other resonant frequencies due to the arc slot insertion ef ect. Meanwhile, the single GPS L1 antenna works at a frequency of 1.575 GHz with right circular polarization due to the insertion of an tilted slot. The antenna is designed on a Rogers/duroid 5880 substrate with a dielectric constant of 2.2 with a length of 228.6 mm, width of 304.8 mm and thickness of 0.254 mm. The antenna is placed on the surface of an iron tube with a diameter of 200 mm, a length of 300 mm and a thickness of 10 mm. Feeding antenna uses a proximity coupling that connects to the coaxial cable from the bottom layer of the substrate to the inside of the tube. The prototype result shows that desired frequencies shifts to 0.99 GHz, 1.67 GHz and 2.26 GHz. The S11 and S22 values obtained were less than -10 dB. Some unnecessary frequency resonances are suppressed with an S11 value of approximately -5 dB. The S21 value is less than - 40 dB for the entire frequency range. The gain values are less than 0 dBi at the three resonance frequencies. GPS L1 polarization is RHCP with an axial ratio value of less than 3 dB. The radiation pattern of the these frequencies has nearly omnidirectional with dips and nulls in certain directions.