This paper proposes a new design of a triple-band dual-polarized indoor base station antenna for mobile communication systems serving the 2G, 3G, 4G, and the new sub-6 GHz 5G applications The design consists of two orthogonal dipole antennas to provide dual polarization Each dipole consists of three different radiator types—elliptical dipole, bowtie dipole, and cat-ear shaped arms for different bands The proposed antenna offers three broad bands with the fractional bandwidths of 313% (07–096 GHz), 553% (17–3 GHz), and 14% (33–38 GHz) which can be controlled independently The design also offers stable radiation patterns within the desired frequency bands, high polarization purity and, a simple feeding structure with a compact size and low profile which make this new design an ideal candidate for indoor mobile base stations serving the 2G, 3G, 4G, and the new sub-6GHz 5G applications

A Triple-Band Dual-Polarized Indoor Base Station Antenna for 2G, 3G, 4G and Sub-6 GHz 5G Applications

A state‐of‐art review on band‐notch characteristics in UWB antennas

Penta-band notched ultra-wideband monopole antenna loaded with electromagnetic bandgap-structures and modified U-shaped slots

In this paper, an ultra-wideband (UWB) monopole antenna with penta-notched rejection characteristics is proposed. The first three rejected bands, 2.6 GHz (LTE band), 4.0 GHz (C-band satellite downlink), and 8.0 GHz (X-band satellite uplink), are obtained using two fork-shaped slots embedded on the radiating patch, respectively. However, additional two notched frequencies for 5.5 GHz (WLAN band) and 6.5 GHz (C-band IEEE INSAT) applications are achieved by spiral line electromagnetic bandgap (EBG) structures. The designed antenna is fabricated over FR4 substrate and has a compact size of 31.3 × 34.9 × 1.6 mm
 3
 and is covering the impedance bandwidth of 2.9–10.5 GHz. Moreover, the suggested antenna has efficient notch controlling capabilities, and its performance characteristics are evaluated and analyzed in terms of rejecting frequencies, surface current distributions, radiation patterns, etc.

Penta-notched UWB Monopole Antenna Using EBG Structures and Fork-Shaped Slots

A flexible E-shaped patch antenna that is particularly easy to fabricate is presented. E-shaped patch antennas traditionally act as wideband microstrips. Here, first a novel folded L-shaped feed is used for improved wideband operation. Then, multiband operation is enabled through scaling and tight packing with low mutual coupling. The antenna equivalent circuit is presented, and the principles of operation at the two modes of the antenna are discussed. The traditional design undergoes a clever modification to allow it for particularly easy fabrication, which minimises the need for complex tools and enables a low budget manufacturing, and the methodology for this modification is presented. The fabricated prototype exhibits fractional bandwidth larger than 20% with extremely small total antenna dimensions 18 mm × 19 mm (about λ
 0
/4 × λ
 0
/4 at the centre frequency). The proposed design can be particularly useful in multiband array configurations through the demonstrated scaling and tight packing, as well as for wearable applications.

/pdf/modified-easy-to-fabricate-e-shaped-compact-patch-antenna-2k5l39qc80.pdf

Modified easy to fabricate E-shaped compact patch antenna with wideband and multiband functionality

A planar ultra-wideband (UWB) antenna with quad notched bands is proposed and its performance is investigated in this paper. The designed UWB antenna consists of a rectangle-shaped radiating patch with tapers and a polygon ground plane with a rectangular slot. A rake-shaped resonator (RSR) and a pair of L-shaped slots (LSSs) are employed to achieve the desired four notched bands which are operated at 3.3–3.6GHz for WiMAX, 3.9–4.0GHz for C-band, 5.6–5.9GHz for WLAN and 7.9–8.2GHz for ITU 8 GHz band. The results show that the proposed antenna has very wide bandwidth ranging from 2.7 to 12.0 GHz with respect to VSWR < 2, which can cover entire UWB band except the four frequency rejection bands.

A planar UWB antenna with quad notched bands using rake-shaped resonator and L-shaped slots

In this paper, an E-shaped triple-band patch antenna is proposed for LTE operation at lower band (920–960 MHz), middle band (1.9–2.2 GHz) and upper band (3.4–3.8 GHz). The proposed E-shaped patch antenna is fed by coaxial probe. Two metal shorted pins are used to connect the E-shaped patch to the ground and two rectangle slots are etched on the ground plane to obtain the desired triple-band operation. The simulation results show that the proposed E-shaped patch antenna not only covers three LTE bands, but also has the good directional radiation patterns, which can be used in most of the LTE communication systems.

A modified E-shaped triple-band patch antenna for LTE communication applications

A coplanar waveguide (CPW)-fed quad-band monopole antenna is proposed and analyzed by using four meander lines for L-band, 2.4 GHz wireless local area networks (WLAN)and 3.5 GHz worldwide interoperability for microwave access (WiMAX) communication applications. The desired quad frequency bands are generated by means of four meander lines. The simulation results indicate that the optimized CPW-fed quad-band monopole antenna can operate at 1.15–1.25 GHz and 1.5–1.9 GHz for L-band, 2.39–2.49 GHz for WLAN and 3.5 GHz for WiMAX communication applications with respect to S 11 < −10 dB. Additionally, the proposed antenna gives a good impedance matching characteristic and almost omnidirectional radiation patterns in the operation bands, making it suitable for multi-band wireless communication applications.

A CPW-fed quad-band monopole antenna for L-band, WLAN and WiMAX communication applications

An ultra-wideband (UWB) antenna with quad notch bands is presented by using two similar fork-shaped resonators (FSRs) settled aside the feed transmission line. The proposed antenna is printed on a substrate with a relative permittivity of e 4 = 2.65 and a loss tangent of δ = 0.001, and the designed antenna consists of a microstrip feed structure, a modified trapezoidal ground plane, a fan-shaped radiating patch and two FSRs. By adjusting the dimensions of two close FSRs, the center frequencies of these four notch bands are tunable. The simulation results indicate that the optimized fan-shaped band-notched UWB antenna can work in the entire UWB band (3.1 GHz–10.6 GHz), and filter out undesired narrowband signals from C-band, WLAN, X-band satellite communication systems and ITU 8 GHz band, respectively. The proposed antenna can not only provide four designated rejection bands, but also have good impedance characteristics and near-omnidirectional radiation patterns, making is very suitable for modern UWB communication applications.

A fan-shaped quad band-notched UWB antenna using two fork-shaped resonators

The total quota control and reserve of rare earths are important means for the sustainable development and utilization of rare-earth resources. Focusing on the government reserve of rare-earth products under stochastic demand, this paper analyses the interactive decisions of the government and the rare-earth firms from a game-theoretic perspective. The government determines the total quantity, reserve quantity and reserve–release quantity of the rare-earth products to maximize social warfare, while the firm decides the price of rare-earth products to maximize its own profit. The results show that the production cost and the expected net present value (NPV) of the reserve are important factors affecting the government’s decisions. When the expected NPV of the reserve is below a threshold, the government adopts the no-reserve strategy: it determines only a total quota index that maximizes the current-period social welfare but keeps no reserve. When the expected NPV of a reserve is higher than the above threshold but lower than the production cost, the government adopts the low-reserve strategy: it determines a total quota index and a low reserve that are both in increasing in the expected NPV of reserve, and will release the reserve as many as possible if there is a supply shortage. When the expected NPV of a reserve is higher than both the above threshold and the production cost, the government adopts the high-reserve strategy: it sets a total quota index which is sufficiently large to cover the entire market demand, reserves a large amount, and releases part of the reserve to completely fill the demand gap (if any).

https://www.mdpi.com/2071-1050/14/22/14883/pdf?version=1668673883

Xianping Luo

Papers

A planar UWB antenna with quad notched bands using rake-shaped resonator and L-shaped slots

A modified E-shaped triple-band patch antenna for LTE communication applications

A CPW-fed quad-band monopole antenna for L-band, WLAN and WiMAX communication applications

A fan-shaped quad band-notched UWB antenna using two fork-shaped resonators

Government Reserve of Rare Earths under Total Quota Management: An Interactive Game between Government and Rare-Earth Firms