X-BAND ISOFLUX MICROSTRIP PATCH ANTENNA ARRAY DESIGN FOR LEO SATELLITES


Alpagu E., Ördek S., Kızılay A.

Euro Asia International Conference on Applied Sciences, Ankara, Türkiye, 30 Kasım - 02 Aralık 2018

  • Basıldığı Şehir: Ankara
  • Basıldığı Ülke: Türkiye

Özet

The Low Earth Orbit (LEO) levels are used by different satellite types such as communication

satellites, earth monitoring satellites, scientific satellites and observation satellites. The orbiting time

of satellites is restricted due to their limited energy. For this reason, the loads that is located on

satellite should be designed to have low mass and they should consume the limited energy efficiently.

The antennas are basic loads on LEO satellites. Various antenna types are used in space applications

such as parabolic, helical and array antennas. However, antennas with specialized specifications are

needed within the increase in technology. The main specifications are the small size for the

development of mini satellites and the agility of beam forming. The microstrip patch antennas can be

used for the small size feature. The microstrip patch antennas are simple to design, easy to construct

and fabricate, cheap and have low mass and height.

Agility in beam forming is achieved by antennas that operate with different patterns, such as the

directional beam, the multi-directional beams and the wide-angle beams commonly known as isoflux.

Isoflux is sometimes named as saddle-shaped, M-shaped or bowl-shaped. The goal of the isoflux

pattern of the antenna is to compansate the distance variation from the satellite to the ground along the

surface curvature of the earth to provide constant power density over the ground covered by the

antenna radiation pattern. In addition, the numbers of satellites needed for covering all the points in the

coverage area on the Earth are minimized by exploiting these antennas.

In this work, a microstrip patch antenna array with isoflux radiation pattern is presented for LEO

satellites. When high transmission rate is required to transmit high volume of image data stored

onboard the satellite, X-Band high gain antenna plays an important role in mission of earth

observation from space. The proposed antenna is designed to be used in X-Band uplink. The antenna

array is simulated by the CST microwave Studio 2018.