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Pattern and Polarization Diversity in Antennas
Published in Binod Kumar Kanaujia, Surendra Kumar Gupta, Jugul Kishor, Deepak Gangwar, Printed Antennas, 2020
Ashwani Kumar, Prashant Chaudhary
To further show the effectiveness of the pattern diversity, the hand-held mobile antenna and the DRA based MIMO antenna is presented. For a small hand-held device, the planar inverted-F antenna (PIFA) is generally preferred. Figure 5.10a shows two PIFA son a common large ground plane of dimension 65 mm × 55 mm operating in the frequency range of 2.27–2.70 GHz. To make the radiation pattern directional, the PIFAs are placed opposite to each other in space; hence, their radiation patterns become directional. Since these two antennas are placed in the opposite directions, the radiation patterns of both the antennas are also in the opposite directions, as shown in Figure 5.10c. There is no overlapping between the two radiation patterns, which also provides a high isolation between them.
Antenna Parameters, Various Generic Antennas and Feed Systems, and Available Software
Published in Lal Chand Godara, Handbook of Antennas in Wireless Communications, 2018
Jennifer Bernhard, Eric Michielssen
A PIFA consists of a top plate element, a ground plane, a feed wire attached to the top element through a hole in the ground plane, and a shorting wire or strip that is directly connected between the top element and the ground plane. Related to both the linear inverted-F antenna15 and the short-circuited microstrip antenna,16 a typical design is shown in Fig. 5.19.17 The design of the antenna involves selection of the top plate width, length, and height above the ground plane as well as the location and width of the feed wire and the shorting strip. For PIFA antennas on an infinite ground plane, the resonant frequency varies with the width of the shorting strip and the dimensional ratio of the top element.13,17 On finite ground planes, these relationships are not as straightforward and design often requires the trial-and-error approach.17 In general, the impedance bandwidth of the basic antenna is determined by the height of the top element above the ground plane with some additional bandwidth resulting from surface currents on a noninfinite ground plane or conductive mounting structure.17Figure 5.20 illustrates the radiation patterns of a PIFA antenna mounted on the side of a radio housing.18 These patterns demonstrate the PIFA’s ability to send and receive both vertically and horizontally polarized fields, making it an appropriate choice for portable devices where the antenna orientation is not fixed.
Novel Wearable Antennas for Wireless Communication Systems
Published in Albert Sabban, Novel Wearable Antennas for Communication and Medical Systems, 2017
The use of microstrip antennas is well known in mobile telephony handsets [30]. The PIFA (planar inverted F antenna) configuration is popular in mobile communication systems. The advantages of PIFAs are their low profile, their low fabrication costs < and easy integration within the system structure. One of the miniaturization techniques used in this antenna system is based on space-filling curves. In some particular cases of antenna configuration, the antenna shape may be described as a multi-level structure. The multilevel technique has been already proposed to reduce the physical dimensions of microstrip antennas. The present integrated multi-service antenna system for communication systems is comprised of the following parts and features.
Compact Slotted Microstrip Antenna for 5G Applications Operating at 28 GHz
Published in IETE Journal of Research, 2022
P. Merlin Teresa, G. Umamaheswari
Antenna design for mobile phones has always been a challenging topic for engineers, and designing antennas to support the new 5G frequency bands will raise the bar further. 5G technologies are expected to provide internet connections that are faster than 4G LTE. 5G technology may use a variety of spectrum bands, including millimetre wave radio spectrum, which can carry very large amounts of data over a short distance. The forthcoming 5G technology will come from various vendors and will be composed of solutions designed to provide very fast download speeds and low latency. Its applications include economic growth, education, health care, transportation, power grid, smart cities, etc. The expected bands recommended for 5G mobile communications are: 27.5–29.5, 42–45, 47–50.2, and 50.4–52.6 GHz [1]. Operating frequency is expected to be around Ka band (26.5–40 GHz). The antenna with operating frequency of 28 GHz will provide better results when compared to the other frequencies. The agile decreases in size of mobile devices prone to develop miniature antennas that could fit in those devices without affecting the function. This caused the raise of compact antennas in twentieth century. A microstrip patch antenna can be integrated very easily on the surface of printed circuit board, which can be used in mobile devices [2]. The planar inverted-F antenna (PIFA) is a type of patch antenna common in cellular phones. The antenna is resonant at a quarter-wavelength, and it has good specific absorption rate properties. This antenna resembles an inverted F, which explains the PIFA name. The PIFA is popular because it has a low profile and an omnidirectional pattern [3]. These antennas are derived from a quarter-wave half-patch antenna. The folded inverted conformal antenna has some advantages with respect to the PIFA, because it allows a better volume reuse.
A RFID switch beam scanning antenna array for application in complex environment
Published in Electromagnetics, 2019
Hua Zhu, Xiuping Li, Quanping Li, Weiwei Feng
A PIFA is designed, which consists of a square patch, shorting plate, metal support plane, feed probe, ground, and plastic prop, as shown in Figure 1. The shorting plate, metal support plate, radiating plate, and feed probe are integrated on the same metal plane to facilitate installation. The shorting plate, metal support plate, and feed probe are located at the FR4 substrate through rectangular slots, feed probe hole. The resonant frequency of PIFA is given by (Huang and Boyle 2008)