ISSN:2249-5789 Govardhani et al, International Journal of Computer Science & Communication Networks,Vol 2(1), 16-21

Rectangular Patch Array Antenna with Liquid Crystal Substrate for Ka and Q Band Applications I.Govardhani1

M.Venkata Narayana2

1.Associate Professor, Department of ECE, K L University [email protected]

2.Associate Professor, Department of ECE, K L University

Abstract: This paper mainly deals with the design of Microstrip rectangular patch array antenna on liquid crystal substrate at 40GHz. The antenna parameters are simulated using commercial Ansoft HFSS software and the detailed explanation of performance evaluation is presented. A 4x4 rectangular patch array was designed on liquid crystal substrate material and their return loss, input impedance, gain and antenna parameters are studied and presented in this paper. Keyword: Liquid crystal substrate, phased array antenna, micro strip

1 Introduction. Micro strip patch antenna consists of a radiating patch on one side of a dielectric substrate, which has a ground plane on the other side. A Micro strip patch antenna/patch antenna is a narrowband, wide-beam antenna fabricated by etching the antenna element pattern in metal trace bonded to an insulating dielectric substrate with a continuous metal layer bonded to the opposite side of the substrate which forms a ground plane.

2 Antenna Model.

Fig:1:antenna model

[email protected] 3 Antenna Design considerations. A 4X4 rectangular patch array antenna with liquid crystal substrate has been designed and simulated at 40GHz frequency in this paper. We have taken liquid crystal dielectric constant (Єr) as 3 and loss tangent (δ) as 0.003. If „L‟ is the resonant length of patch, normally width (W) should be larger than L so that large bandwidth can be obtained. Here we have taken width (W) as 1.5 times of length (L). Height of the dielectric substrate should be in between 0.003 λ0 and 0.05λ0. We have taken 0.02 times of λ0. As 50Ω coaxial cables are used normally, feed point is taken where 50Ω resistance occurs.

4 Patch Model.

Fig:2:patch model

5 Liquid crystal substrate. Liquid Crystal Polymer (LCP) is a fairly new and promising thermoplastic organic material. It can be used as a low-cost dielectric material for high-volume large-area processing methods that provide very reliable high-performance circuits at low cost. It has impressive electrical characteristics, which is indirectly related to its low and stable water absorption rate (