Keywords

1 Introduction

The simple dictionary meaning of an antenna is that it is usually metallic device (as a rod or wire) for radiating or receiving radio waves [2, 8]. The IEEE standard definitions in terms for antennas is defines the as “a means for transmitting or receiving radio waves.” In other words, the antenna is the transitional structure between free space and a guiding device [10]. The antenna is also referred to as aerial. So in simple words antenna is defined as “a transducer which convert electromagnetic waves into required electrical signal at receiver and also a metallic device used for transmitting or receiving electromagnetic waves which acts as the transition region between free spaces and guiding structure like a transmission line in order to communicate even in a longer distance.”

By using various Nanomaterials and CNTs we will fabricate a patch on which by suitable probe feed we obtain maximum bandwidth and efficiency of antenna. Also use suitable substrate on which patch is fabricated by masking and lithography process. Masking can be done by software (like Coral, Autocad) simulations. For compactness in advanced communication system, may be it wired or wireless communication, miniaturization is the basic needs. Microstrip patch antenna is most commonly used now a days for mobile applications or Wi-Fi, Wi-Max applications [9]. So antennas can be easily compatible with the application areas of embedded and fabricated antenna used in handheld wireless devices such as cellular phones, pagers etc. [4]. The telemetry and communication antennas on missiles need to be thin and conformal and are often in the form of Microstrip patch antennas. Another application is Radar communication and Satellite communication. In this communication rectangular patch is chosen for better response and ease of analysis rather than any other shapes.

2 Antenna Design

This given design having these dimensions: Ground dimension = 100 × 100. Ground cut at point (0, 50). The geometrical representation of proposed antenna [1] is shown in Fig. 1.

Fig. 1.
figure 1

Ellipse design having ground cut and patch cut

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At patch, at axis (−25, 0), having length L = 50 mm and width W = 20 mm, cut at angle 90°. Ellipse major axis a = 30 mm, Ellipse Minor Axis b = 20 mm. ∈ r = 4.4, tangent loss = 0.025, h = 1.59.

There are few considerations or parameters for the design of a rectangular Microstrip Patch Antenna which will be taken care of: A substrate with a high dielectric constant has been selected since it reduces the dimensions of the antenna according to our application. The resonant frequency (fr) of the antenna must be selected appropriately. The Mobile Communication Systems uses the frequency range from 2 to 6 GHz. By doing this we fabricate or design an antenna which will be able to operate in the desired frequency range [5, 6]. The resonant frequency selected for my design is 3–8 GHz.

For the microstrip patch antenna to be used in cellular phones, it is essential that the antenna is not bulky. So, the dielectric substrate is selected as 1.59 mm height (h).

Hence, the essential parameters for the design are: fo = 3–8 GHz, εr = 4.4 and h = 1.59 mm.

Zeland Inc’s IE3D is the software we used to model and simulate the Microstrip patch antenna. IE3D is a full-wave electromagnetic simulator based on the method of moments. It analyzes 3D and multilayer structures of general shapes. It has been widely used in the design of MICs, RFICs, patch antennas, wire antennas, and other RF/wireless antennas [2]. It can be used to calculate and plot the S11 parameters, return losses, smith chart etc. as well as the radiation patterns (Fig. 2).

Fig. 2.
figure 2

A fabricated design of elliptical microstrip patch antenna with coral draw model

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3 Result

The return loss for the patch antenna can be measured on a network Analyzer [7, 10]. The pattern created in a far field test can be shown as E-plane and H-plane patterns [13], (preferably in an anechoic chamber) calculated with a standard gain antenna as a transmitting antenna and the Antenna under test as a receiving antenna mounted on a pedestal [7]. Layout generation can be done in coral draw or autocad software for preparing the mask. Once the mask is printed on a transparent sheet, the patch can be fabricated using conventional photolithography process [10]. Once the dimensions are obtained the antenna can be simulated on a commercially available 2.5D or a 3D EM simulator [7, 10]. Further optimization and fine tuning of dimensions, other parameters like axial ratio, smith chart, 2D pattern etc. can be carried out to bring the resonance back at the desired frequency with acceptable return loss (Fig. 3).

Fig. 3.
figure 3

Return loss in dB

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The radiation pattern of antenna represents the radiation property of antenna as a function of space coordinates. The pattern gives the normalized field (power) value w.r.t. the maximum value [13]. In patch antenna various radiation properties include directivity, gain, power flux density, radiation intensity, radiation resistance, field strength, phase polarization. It will resonate at the frequency of 4.15 GHz, it means antenna give maximum radiation at this frequency (Fig. 4).

Fig. 4.
figure 4

Smith chart

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Impedance calculated is 36.19–2.27j, by showing these values we see that the antenna impedance is not properly matched so there is losses occur in these design. So to rectify this problem we will shift or change the probe position by proper dimension and check the result on IE3D simulator (Figs. 5 and 6).

Fig. 5.
figure 5

Graph between efficiency versus frequency of elliptical patch antenna

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Fig. 6.
figure 6

2-D pattern

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Here we see that the antenna efficiency and radiation efficiency is 40.77 and 42.75% respectively. As we see in figure, by increase in the frequency we obtain the maximum efficiency. We generally use S band frequency range applications by this proposed design. The maximum bandwidth is 7.47 Hz at maximum resonant frequency i.e., 4.15 GHz (Fig. 7).

Fig. 7.
figure 7

Axial ratio at 0° and 90°

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3.1 Simulation Setup and Results

Freq.

Return loss

Impedance

Bandwidth

Antenna efficiency

Radiation efficiency

Axial ratio (0, 90)

4.15

−15.81

36.19-2.27j

7.47

40.77

42.75

15.21, 25.38

4 Conclusion

We propose a design and fabrication of elliptical microstrip patch antenna in this paper. Our main objective is work on the allocation of frequency bands for communication purposes which will be called the L & S band (ranging from 1 to 4 GHZ). The 2.45–2.484 and 5.15–5.825 GHz frequency bands have been adopted by IEEE 802.11a5 for wireless local area networks (WLAN) [13]. The maximum absorption value will be achieved by designing that antenna with the composition of nanomaterial as base, maximum absorption ratio will be achieved. The study explicitly showed that the nanomaterial or CNT [11] with patch material i.e., copper, this compound show possibility of EMI shielding for various applications up to X band frequency range [12]. So by using this design in elliptical microstrip patch antenna we find various results by changing the position of probe at same ground cut, patch cut etc. Without ground cut we obtain better gain but poor bandwidth. As we change probes in a constant ground cut, its bandwidth and efficiency is improved.