IJSRD - International Journal for Scientific Research & Development| Vol. 1, Issue 12, 2014 | ISSN (online): 2321-0613 All rights reserved by www.ijsrd.com 2616 Abstract--- The design & analysis of close-ended quadrifilar Helix antenna for Ku-band is proposed here. A hollow ceramic rod is used as a dielectric load to reduce antenna size of an air-loaded quadrifilar helix antenna. This antenna is proposed to be used for transmission of satellite telemetry data with Directional coverage in Ku-band for satellite communication. A hemispherical circular-polarized radiation pattern and reasonable gain will be measured. It will be measured and simulated return loss, axial-ratio, radiation pattern, and realized gain are presented and discussed together with design guidelines. Keywords: Quadrifilar helix antenna, Satellite communication, telemetry data transmission. I. INTRODUCTION Quadrifilar helix antennas (QHAs) are widely used for both space and terrestrial communication systems where it is necessary to generate a circularly polarized cardioid shaped pattern with a high front to back ratio and low cross polarization. In addition, the antenna does not require a ground plane to radiate efficiently and therefore it is a particularly attractive option for use in mobile handsets and spacecraft payloads where real estate is very limited. Nevertheless, it is desirable to reduce the axial length of the antenna particularly for satellite communications systems in the VHF and UHF bands where it is often difficult to accommodate these antennas in the launch vehicle. [2] The quadrifilar helix antenna (QHA) is usually used in low Earth orbit (LEO) satellite communications, handsets of global positioning system receivers and satellite mobiles. The distinguishing features of this antenna are its cardioids pattern, circular polarization, and logical size compared to other antennas. In particular, the cardioid pattern is the favourite pattern for LEO satellite antennas. Fig. 1.Dimensions of the QHA. [1] The QHA belongs to the family of resonant antennas. Hence, its dimensions have to be selected appropriately to obtain optimum characteristics in a desired narrow frequency band So far, several designs have been presented for dual-band QHAs. Almost all prior ideas are based on designing the QHA to achieve a cardioid pattern. This approach causes some restrictions either on gain or on size. This work presents a miniature dielectric-loaded resonant QHA, which is a suitable way of miniaturizing an antenna without changing its geometry such that the radiation pattern is degraded. A ceramic rod is used due to its low loss and high permittivity. [3] Fig. 2: Antenna structure including the adapted PCB with a SMD capacitor. [3] Fig. 3: Bottom view of the QHA . [3] Fig. 4:.close-ended QHA. Design & Analysis of Close-Ended Quadrifilar Helix Aantenna At Ku-Band For Satellite Communication Sachin Patel 1 Prof.Niraj Tevar 2 1,2 EC Department, Parul Institute of Technology 1,2 PIT-Limda, Vadodara, India