Multiband ladder‐shaped monopole antenna for digital television and wireless communications

Abstract

selectivity. The measured results closely match with the simulated results. The overall size of the fabricated filter is around 25 ϫ 25 mm, indicating the proposed filter exhibits the property of compact size, easy fabrication, and good performance. CONCLUSIONSIn this letter, a UWB BPF with a notch band of 5-6 GHz is proposed. To improve the stopband performance, a bandstop filter using mixed open stubs for suppressing spurious response has been proposed. The proposed BSF shows a deeper rejection and a wider stopband than the conventional open-stub BSF without increasing the circuit size. The proposed UWB BPF shows a lower passband of 3.5-5.2 GHz and a higher passband of 6.5-9.7 GHz as well as 23 dB rejection during the frequency range from 10 to 20 GHz. The measured results of the fabricated UWB BPF actually match with the simulated results. INTRODUCTIONAn antenna with function of multiband operation can provide a single device to simultaneously use different frequency bands for appropriate communication systems without the conventional requirement of using multiple single-frequency antennas. In literature, a lot of multiband antennas have been proposed for application in systems such as the Globe System for Mobile (GSM), Industrial Science-Medical (ISM), and Wireless Local Area Network (WLAN), etc [1][2][3][4][5]. However, for a recently developed device, the digital television (DTV), which has already received much interest and increasing demand to be equipped into a personal mobile communication system due to its attractive function in effectively providing audio/video entertainment features with good resolution, it is hardly seen on inclusion of its operation band to a general-purposed multiband antenna, so far [6 -11].In this article, a novel multiband planar monopole antenna with a simple structure of utilizing a ladder-shaped patch fed by a microstrip line is presented. By properly choosing the sizes of the radiating patch and the ground notch, a monopole antenna with dual and wide impedance bandwidths and suitable radiation characteristics for modern multiband wireless communication such as the DTV/GSM/IMT-2000/WiMAX/WLAN operation can be obtained. Details of the antenna design and both theoretical and experimental results are presented and discussed. ANTENNA DESIGNThe configuration of the proposed ladder-shaped monopole antenna for multiband operation is shown in Figure 1. The antenna was printed on an inexpensive FR4 structure with thickness (h) of 1.6 mm and relative permittivity (e g ) of 4.4. The main radiating structure of this antenna printed on the top surface of the substrate is a ladder-shaped patch and consists of three sub-patches with sizes of 15 ϫ 28 mm 2 , 54 ϫ 15 mm 2 , and 84 ϫ 82 mm 2 , respectively. A 50-⍀ microstrip line with dimensions of width 2.5 mm and length 105 mm is used to feed the patch. As for the ground plane, it was printed on the bottom side of the substrate and has an overall size of width 100 mm and length 123 mm. In this design, for improving the impedance matching ...

A wearable multiband monopole antenna for digital television and wireless communications

“…A textile antenna for DTV reception was developed in [5] and was redesigned in [6] for improved bandwidth, however its size was large. A monopole DTV antenna that also covers the wireless communication standards was presented in [13] and it was also redesigned in [7], using felt substrate and Nora textile for the conducting parts.…”

Printed Dipole Antenna With Back to Back Asymmetric Dual-C-Shape Uniform Strips for DTV Applications

“…For this reason, a simple antenna as a transducer between the DTV transceiver and the propagating medium is much desirable if it could operate at DTV bands. Planar printed antennas include broadband dipole [1,2] and broadband monopole antennas [3][4][5]. On account of horizontally polarized DTV signals, the horizontally oriented antenna is a very promising candidate for DTV signal reception, and desirable radiation patterns for devices are usually omni-directional, therefore, a dipole antenna could be expected.…”

CPW-Fed Sleeve Monopole Antenna With Complementary Sir Radiators for DTV Signal Reception and Circularly Polarized Applications

“…The digital television (DTV) reception has been very attractive for applications in recent wireless communications. Many kinds of antennas for DTV reception have been studied [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16], and delivering broadcast television signals to various terminals such as mobile phone [1], laptop computer [2,3], multi-media player [4][5][6], vehicle [7] and the reception devices [8][9][10][11][12][13][14][15][16], etc.…”

“…Basically, these structures belong to the monopole [2,[4][5][6][7][11][12][13][14][15], dipole [1,3,[8][9][10], planar [17] and the loop [16]. The characteristics of these antennas include broadband, compact, omidirectional patterns and high gain.…”

“…By inserting a parasitic sleeve with square loop, the impedance performance is dramatically improved. The asymmetrical radiators consists of the step impedance resonator (SIR) [14] and the complementary configuration [18,19]. The CP operation for the proposed design can be achieved by properly adjusting the asymmetrical radiators.…”