# Dual-Band UWB Monopole Antenna for IoT Applications +
## 2 Literature Review  
In 1990, the first CPW-fed antenna was proposed. Alternative designs include tapered slot antennas with coplanar waveguides. The CPW microstrip antenna, which has a rectangular slot, circularly polarized antenna with a CPW-fed circular patch, dual-polarization antenna, and a miniature tapered-slot antenna, can be used for various applications. The radiating elements that have been proposed are challenging to build; the bandwidth achieved is insufficient, and it has very limited applications. Building a CPW-fed antenna with a simpler structure and much higher efficiency, as well as a larger bandwidth, is difficult [17]. The most common feeding strategy is microstrip line feeders. However, CPW feeding is favored because the ground plane resembles radiator components.  
The CPW-fed antenna, unlike the microstrip line feeder, has a ground plane on its upper radiation components. As reported in [18], CPW can be combined with CPW-fed monolithic microwave integrated circuits. The use of a minor, dual-notch band and CPW-fed ultrawideband antenna was reported in [19]. In this case, the antenna has notch bands that can be selected between 4 and 5.78 GHz and 6.83 and 8.22 GHz. A low-cost FR-4 substrate-integrated octagonal patch antenna can be built. A new small-size UWB microstrip antenna with a dimension of 1327.2 mm\({}^{2}\) was made on an FR4 substrate usinga decreased ground plane and slotted patch resonator. A CST electromagnetic simulator planned antenna was simulated, and it has three resonances of 8.5, 5.2, and 3.1 GHz with S11 values of 22, 21.8, and 20.5, respectively, and 6.23 GHz as the impedance bandwidth. This antenna was made and tested to validate the simulation's input reflection results, and the experimental results and simulated results were consistent [20]. To increase the gain single-layer frequency, a selective surface was used as a metallic plate in a SAPM (strawberry artistic-shaped printed monopole). This improved the antenna's UWB frequency range. The strawberry-shaped radiating element was created using six cylinders. With a bandwidth of 8.85 GHz (3.05-11.9 GHz), this antenna with CPW feeding was projected on an FR4 substrate, covering the acceptable UWB frequency range. An antenna with a FSS reflector yielded a 6.22 dB gain in the upper and lower bands. The antenna measures 61 \(\times\) 61 \(\times\) 1.6 mm\({}^{3}\). Because of its directed pattern and balanced far-field, the recommended antenna layout can be used in UWB and ground-penetrating radar (GPR) applications [21]. An antenna based on an FR4-epoxy substrate with antenna dimensions of 23.5 \(\times\) 31 \(\times\) 1.5 mm\({}^{3}\) was reported in [22]. The operating frequency range of the proposed antenna is 1.76-11.07 GHz, and the frequency range of 2.42 to 5.37 GHz is rejected. The proposed antenna has significant gain, consistent radiation patterns, and efficiency across the entire working spectrum. Finally, the proposed antenna may be viable for wireless communication. For personal wireless communication, a compact-band notched UWB antenna and UWB applications have been proposed [23]. A lightweight, small UWB antenna with improved efficiency gain was reported in [24]. To create the proposed antenna design and feed a jug-shaped radiator, a CPW was used. This antenna had a gain of 4.1 dBi and a frequency range from 3 to 11 GHz. In [25], a U-shaped aperture with two split ring resonators (CSRR) and two stubs is proposed. The dimensions of the proposed antenna are 24 \(\times\) 20 mm\({}^{2}\), and an FR4 substrate is used operating at frequencies ranging from 2.7 to 11.4 GHz. The antenna also had an impedance band of 123.4%. An antenna consisting of four crescent-shaped nested rings operating at a frequency range of 2.63-11.6 GHz is reported in [26]. With a gain of approx. 4 dB, this antenna can be used in UWB applications.