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This paper represents parallel notch, H-shape slot loaded single layer patch antenna in X, and Ku bands for wideband applications. The design has made on low-cost material of Rogers R03003 substrate having dielectric constant of 3.0 with thickness of 1.6.0 mm. The proposed scheme and probe feeding technique provide designed antenna to operate in two different frequencies range in X and Ku band (10.60 GHz to 15.91 GHz). The antenna resonates at 11.37 GHz for X band and another three resonates at 12.13 GHz, 13.14 GHz and 14.66 GHz for Ku band with maximum gain of 9.20 dBi respectively. The simulation results have been obtained 40.01% impedance bandwidth with return loss ( -10 dB) or . The proposed antenna is simple in structure compared to the regular single layer patch antennas. It is highly suitable for satellite and RADAR communications system. Designing and simulation of this antenna have been done by IE3D software version 12.0, which is based on MOM method.

Exhaustive research has been carried out to develop the bandwidth-enhancement techniques by keeping the size of the patch antenna as small as possible. In recent years, with the wider applications of microstrip antennas, many researchers had found many methods, which can improve the bandwidth. The coaxial feed technique is used for the analysis of this antenna because it occupies less space and has low spurious radiation by using Teflon connector. The method of moment (MOM) is used to discuss the electromagnetic radiation characteristics of the microstrip antenna. The simulator tool computes most of the useful quantities of interest such as radiation pattern, input impedance, etc. [

In this paper, the design of X-band and Ku band E-shape notch and H-shape slot loaded rectangular patch antenna at single layer with Co-axial feeding technique has been proposed. The H shape-cutting slot is chosen such that proposed antenna reduced the size and exhibit the wide bandwidth characteristics. Further, the variation of return loss for H shape horizontal side stripes length (W_{n}) and vertical length (W_{2}) has studied to obtain the maximum bandwidth. Simultaneously, the variation of return lost for parallel notch length (L_{s}) and notch width (W_{s}). Radiation pattern characteristics and the gain of the proposed antenna are also calculated. This antenna has improved the bandwidth and gain with reduced the size which are the advantages over the earlier reported paper [

a) Parallel notch and H-slot loaded rectangular microstrip patch antenna

The proposed configuration of the antenna is shown in

The E-shaped is simpler in construction. The two parallel notches have the same length L_{s} and same width W_{s}. The separation [_{1}. There are thus only three parameters (L_{s}, W_{s}, W_{1}) for the notches used here. Similarly, the H-shape slot is simpler in cut in same patch. The two vertical slots have the same length W_{2}, same side stripes width W_{n} and one horizontal slot length L_{2}. The separation [_{2}, W_{n}, and L_{2}, d. A probe feeds a point (−8.925, 2.125) located for good excitation of the proposed antenna over a wide bandwidth. The current distribution of the proposed antenna is given in

b) Design Equation

Because of the fringing effects, electrically the patch of the antenna looks larger than its physical dimensions the enlargement on L is given by [

Δ L = 0.412 h ( ε r e f f + 0.3 ) ( W h − 1 + 0.264 ) [ ( ε r e f f − 0.258 ) ( W h − 1 + 0.8 ) ] (1)

where the effective (relative) permittivity is,

ε r e f f = ε r + 1 2 + ε r − 1 2 1 + 12 h W − 1 (2)

This is related to the ratio of h/W. The larger the h/W, the smaller the effective permittivity [

L e f f = L + 2 Δ l (3)

The resonant frequency for the TM_{100} mode is:

f r = 1 [ 2 L e f f ε r e f f ε 0 μ 0 ] (4)

f r = 1 [ 2 ( L + 2 Δ L ) ε r e f f ε 0 μ 0 ] (5)

An optimized width for an efficient radiator is,

W = 1 ( 2 f r ε μ 0 ) × 2 ε r + 1 (6)

c) Design Procedure

If the substrate parameter ( ε r and h) and the operating frequency ( f r ) are known then we can easily calculate the dimensions of the patch antenna using above simplified equation following design procedure to design the antenna:

Step 1: Using Equation (6) to find out the patch width W.

Step 2: Calculate the effective permittivity using the Equation (2)

Step 3: Compute the extension of the length using the Equation (1)

Step 4: Determine the length L by solving the equation for L giving the solution.

From Equation (6), (f_{r}) is the resonance frequency at which the rectangular microstrip antenna is to be designed. The radiating edge W, patch width is usually kept such that it lies within the range for efficient radiation. The ratio gives good performance according to the side lobe appearances. The actual value of resonance frequency is slightly less than because fringing effect causes the effective distance between the radiating edges of the patch to be slightly greater than L. By using the above equations, we can find the values of actual length of the patch as:

L = [ 1 ( 2 f r ε r e f f ε 0 μ 0 ) ] − 2 Δ L (7)

Whole dimensions of the prescribed Antenna are given in

The most sensitive parameters are found to be the thickness of substrate, shape and size of slots; notches are selected for the parametric study. To accurately understand the influence of these parameters on its impedance bandwidth, only one parameter at a time was varied, while others were kept constant.

We first show simulation results to illustrate the main features of the method.

The microstrip patch antenna structure is studied and simulated by using IE3D simulation software which is MOM (Method of Moment) based simulation software. As part of the simulation, it is observed that the return loss of the microstrip patch antenna is almost −25 dB, which is quite good when compared to normal antenna structures. Different simulated results are seen by using the

Frequency | 10 - 17 GHz |
---|---|

W | 37.21 mm |

W_{1} | 7.44 mm |

W_{s} | 7.44 mm |

L | 28.89 mm |

L_{s} | 14.44 mm |

L_{1} | 14.44 mm |

W_{2} | 9.0 mm |

W_{n} | 3.0 mm |

L_{2} | 9.0 mm |

d | 3.0 mm |

Dielectric ( ε r ) | 3.0 |

Thickness (h) | 1.6 mm, 2.0 mm |

IE3D results like the return loss, radiation pattern, VSWR, and gain vs. frequency.

antenna is shown in (

The antenna gain over the BW is shown in

The above study shows the influence of size and shape of notches, slots and thickness of substrate on the impedance bandwidth. Wideband and UWB can

be easily achieved with monopole antenna using thick substrate and microstrip line-fed technique. However, our proposed antenna provides a wideband (10.60 - 15.91 GHz) with a thin microwave substrate and using coaxial probe-fed technique without monopole concept. At the same time gain of the antenna is also, high (9.2 dBi). Here lays the novelty of the research work.

The main concern of the paper is to study the wideband and high gain with simple and reduced size patch antenna. Initially, the single element rectangular microstrip antenna is designed to operate at frequency 13.25 GHz. This antenna structure provides a good amount of gain and the directivity along with that, this antenna structure works in two frequency bands as shown in the return loss and VSWR curve and provides good bandwidth. Present antenna is designed to meet the requirement for wide bandwidth with compact size. The proposed antenna is working in X and Ku- frequency band and can be used for satellite and RADAR communication system where simple wideband high gain antennas are desired.

The authors declare no conflicts of interest regarding the publication of this paper.

Yadav, N.P., Hu, G.Z. and Yao, Z.P. (2019) Parallel Notch and H Shape Slot Loaded Compact Antenna for X and Ku Band Applications. Open Journal of Antennas and Propagation, 7, 13-21. https://doi.org/10.4236/ojapr.2019.72002