Reconfigurable High Gain and Wide Band Antenna for 5G Communication

This paper introduces the specification and performance analysis of broad frequency range antenna for 5 G mobile phones. The suggested antenna functions at the frequency spectrum of 28 GHz and its configuration are permanently matched over very high frequency bands, including 4.25 GHz, 7.055 GHz, 12.48 GHz and 15.26 GHz, as well as for the reallocation of the expanded 5 G spectrum of communications. Mobile terminals are compliant with the antenna that is being built.


Introduction
In the transmission of information, the antenna plays a major role in wireless communication. The arrival of new frequency bands adds new obstacles for antenna manufacturers. Second, the number of operating bands is naturally growing, as compatibility with 2G, 3G and 4G is required. Secondly, the antenna volume cannot be increased, leading to the construction of smaller antennas relative to the current antenna capacity. An antenna with more complex structure using parasitic elements is enough to achieve the desired coverage to cover the new frequency bands above 3GHz.
However, the passive antenna technology reaches its limits in low frequency bands. In present days, a significant number of reconfigurable antennas have been used based on various tuning techniques. The rapid growth of 5G communication uses very high frequency bands which requires that the antenna operates at wideband, to cover variety of services like mobile wireless services etc. It is also necessary to reduce the complexity of the system.
There are different design methodologies of antenna to obtain wide operating bands. In this paper meander monopole antenna is used to obtain wideband operating frequencies. Meander monopole antennas are derived from single monopole antenna. In this proposed design a smaller capacitive reactance is replaced by smaller inductive reactance and also with a small inductor resistance to lower noise and improve efficiencies when compared to that of a single monopole antenna.
A plain rod-shaped conductor mounted over a ground plane consists of this proposed antenna. The antenna feed is connected to the monopole on one side and the ground plane on the other side. This is distinct from the dipole antenna in which, between the two halves of the antenna, there are two similar rod conductors, with the transmitter signal added.
Nowadays broader bandwidth, multiband and lowprofile antenna are of peak of time for many applications which need to have a single reconfigurable antenna for multiple frequency bands. This main objective of the paper is to design a meander monopole antenna that operates at very high frequencies. CST studio suite software is used to build and simulate this antenna. The remaining paper is structured as follows: Section 2 consists of various sections of the built antenna, accompanied by a summary in Section 3 of the findings and an overview of different parameters. Section 4 ends the document.

Design of Proposed Antenna
The structure of the anticipated antenna is based on the principle of monopole coupling and parasitic elements. The antenna has a compact 40 mm x 32 mm x 2.7 mm design. FR4-Substratum epoxy is used. Three independent elements compose the structure. The driver component at the core is a meandered monopole fed by a 50-microstrip line [1]. The quarter wavelength at 900 MHz is used as overall length (84mm) of this monopole.   [2]. This meander monopole structure consists of horizontal and vertical lines forming turns. This technology allows designing antenna with small size and provides wideband performance [3]. This design makes it compatible for all mobile terminals and also for other wireless applications. Its third order and fifth order modes are adjusted using the two strips (pink) [4].
A parasitic element in yellow is used to create an additional resonance using the left shorted This element is used to improvement of gain and directivity [5]. The coupling between the driven and the parasitic element is tuned to enlarge as much as possible the bandwidth for the lower capacitance value [6]. In meander monopole structure if the spacing is increased then the resonant frequency decreases. The antenna geometrical parameters are optimized designed and analysed using CST studio suite software [7].
The various parts of the proposed design are shown in Figure 1. The proposed antenna [11][12]design is shown in the Figure 2. The dimensions of the monopole antenna and the parasitic elements are also given in Table 1.

Results and Comparisons
The S parameter is used here to analyses the performance of the given antenna. This is used to measure reflected power from the antenna S11 is being considered. The proposed antenna resonates at four frequencies [8]. The antenna is operating at the frequencies of 4.25GHz, 7.055GHz, 12.48GHz, and 15.26GHz provides better impedances of 57.16Ω, 47.495Ω, 45.337Ω, 46.92Ω and a VSWR of the antenna are 1.157, 1.052, 1.121, and 1.066 respectively [9]. The frequencies at which the antenna resonated is shown by S11 curve and also the gain in dB at those resonating frequencies are also show in Figure 3 and the impedances at the resonating frequencies are also shown in Figure 4.  The maximum directivity of 8.076dBi is obtained at 12.48GHz frequency, with side lobe level at -0.7dB. The far field directivity abs polar plot is shown in Figure 5.
The maximum directivity and its respective frequency are shown in polar plot [10]. The radiation pattern at different frequencies is studied and it is found suitable for mobile and other wireless communication systems. The VSWR measured at the frequencies are found to have the optimum value ranging between 0 and 2 which makes it suitable for a wireless communication system [11].

Conclusion
A wideband antenna is proposed for today's mobile communication and future spectrum reallocation and it is designed using CST studio suite and the output are analysed and verified. The antenna that is being designed has a very compact size which makes it suitable for mobile phones. This wideband is achieved only with the help of the meander monopole antenna structure. The proposed antenna operating at the frequencies of 4.25GHz, 7.055GHz, 12.48GHz, and 15.26GHz provides better impedances of 57.16Ω, 47.495Ω, 45.337Ω, 46.92Ω and a VSWR of the antenna are 1.157, 1.052, 1.121, and 1.066 respectively.