IJSRD - International Journal for Scientific Research & Development| Vol. 3, Issue 04, 2015 | ISSN (online): 2321-0613 All rights reserved by www.ijsrd.com 1928 Design and Analysis of H Plane Horn Antenna at X Band Frequency Rohit S Piske 1 D P Rathod 2 Y S Gothe 3 1,2 Department of Electrical Engineering 3 Department of Research and Development 1,2 Veermata Jijabai Technological Institute, Mumbai 400019, India 3 Forbes Marshall, Pune 411018, India Abstract— This paper presents a design of an H plane horn antenna for microwave system. The key purpose of the study is to design a H plane horn antenna which is used in paper moisture system. The proposed antenna operates within 8-12 GHz .Antenna known as directional antenna which is supported by rectangular waveguide. The H plane horn antenna is purposely chosen to design in order to increase the directivity of the antenna within 16 dB gain. This horn antenna is capable to produce return loss as minimum as possible. The antenna is designed and simulated using CST Microwave Studio. The simulation results show that the H plane horn antenna structure exhibits good radiation pattern over X GHz frequency band. Key words: CST, TE10, H Plane I. INTRODUCTION The horn antenna represents a transition or matching section from the guided mode inside the waveguide to the unguided (free-space) mode outside the waveguide. The horn antenna, as a matching section, reduces reflections and leads to a lower standing wave ratio. There are three basic types of horn antennas: (a.) the E-plane sectoral horn (flared in the direction of the E-plane only), (b.) the H-plane sectoral horn (flared in the direction of the H-plane only), and (c.) the pyramidal horn antenna (flared in both the E-plane and H- plane). The flare of the horns considered here is assumed to be linear although some horn antennas are formed by other flare types such as an exponential flare. The horn antenna is mounted on a waveguide that is almost always excited in single-mode operation. That is, the waveguide is operated at a frequency above the cutoff frequency of the TE10 mode but below the cutoff frequency of the next highest mode The horn is widely used as feed element for large radio astronomy, satellite tracking and communication dishes due to its simplicity in construction, ease of excitation versatility, large gain and overall performance[1,2]. Different kinds of horns can be created by flaring the end of the waveguide in different ways for example in one dimension creates a sectoral horn, e.g.: horns flared in the E or H planes. Flaring the waveguide in both dimensions produces a pyramidal horn. If a circular waveguide is used the flare produces a conical horn. II. DESIGN SPECIFICATION H plane Horn Antenna is designed keeping in view certain specifications. The horn designed for X -band with center frequency of 10 GHz. The horn is designed in such a way that we get maximum radiation in particular direction. The inner dimensions of the waveguide aperture are a= 2.82 cm and b=1.01 cm. Fig. 1: Basic Diagram of H Plane Horn Antenna III. METHODOLOGY The antenna is designed using approximation method of gain. An approximation value of gain 15 dB is used to design the antenna as the gain determines the overall size of the horn antenna. First of all, a rectangular waveguide should be design as to precede the basic horn antenna structure. In order to initiate the basic design, the feeding waveguide is chosen according to the frequency range of interest. The mid frequency is set to be 7 GHz. The inner dimension is chosen to be 2.81 cm x 1.01 cm which is closer to WR-90 that supports the frequency range of 8-12 GHz (X-Band). In this design, 16 dB is selected. Approximately to keep the antenna dimensions small. Design calculations are given as: 1) At 10 GHZ G0= 16 dB WR-90 waveguide 2) a= 2.82 cm , b= 1.01 cm 3) G0(dB) = 16 = 10 log10 G0 ⇒ G0 = 39.81 4) χ(trial) = G0/(2π sqrt(2π)) ⇒ 2.52 cm 5) ρh = (λ* ((G0)^2)/8π3*χ) ⇒ 7.504 cm 6) ρ2 = ρh cos(ψh) ⇒ 6.498 cm 7) a1 = sqrt(3λρ2) ⇒ 8.12 cm Fig. 2: CST Studio H Plane Horn Antenna IV. RESULT AND DISCUSSION Once the design completed, the antenna is simulated through the CST software. The results of parameters that obtained from simulation are the frequency, return loss, voltage