Mobile Handset Applications Research Articles

High-Powered RF SOI Switch With Fast Switching Time for TDD Mobile Applications

This paper presents a fast switching and high-powered single-pole double-throw (SPDT) switch for RF switch circuits, such as TRx antenna switches and frequency band (or operation mode) selection switches in mobile handset applications. For fast switching time and performances of the RF switch, we proposed a novel method that can “selectively” control the impedance of a gate biasing circuit (“high” or “low” impedance). The proposed SPDT switch use the low impedance of the gate biasing circuit for fast switching time and use the high impedance of the gate biasing circuit to avoid the degradation of the insertion loss and harmonics. The proposed SPDT switch has no additional bias and no large payment for size consumption. According to measurement results, the turn-on switching time of the proposed SPDT switch was <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.35~\mu \text{s}$ </tex-math></inline-formula> (at 2 GHz). The insertion loss, isolation, and return loss at 2 GHz were 0.16 dB, 47.1 dB, and 24 dB respectively. 2nd and 3rd harmonic levels at 25 dBm input power at 2 GHz were −88.7 dBm and −78.9 dBm, respectively. Power handling capability was 39.5 dBm of input power at 2 GHz. The designed SPDT switch was implemented in a 0.13- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> partially depleted silicon-on-insulator (PD-SOI) process.

Wideband Vertically Polarized Antenna With Endfire Radiation for 5G Mobile Phone Applications

This letter presents a wideband slotted substrate integrated waveguide (SIW) antenna for millimeter-wave (mm-wave) fifth-generation (5G) mobile handset applications. The antenna is vertically polarized and has a small clearance of 3.3 mm. To realize a wide operating bandwidth, two sets of vias are employed to perform a change in SIW height. Furthermore, a pair of U-shaped slots is used in both top and bottom faces of SIW to improve impedance matching and front-to-back radiation ratio. The antenna achieves a measured −6 dB bandwidth of 35.7% (23.4–33.6 GHz) and a −10 dB bandwidth of 17.4% (26.2–31.2 GHz). The beamforming capability of the antenna array is investigated. The antenna array has good scanning performance and achieves large spatial coverage.

Study of a New Design of the Planar Inverted-F Antenna for Mobile Phone Handset Applications

This paper suggests a new design of the PIFA antenna for mobile phone handset applications. In this context, we are interested in the development of new techniques based on the creation of slot matching for the improvement and miniaturization of a dual-band PIFA antenna operating at 900MHz and 1800MHz. Analysis of antenna parameters such as return loss (S11), radiation pattern, Voltage Standing Wave Ratio (VSWR), current distributions, gain, and the relation between them are performed in CST software. There is a good agreement between the results of simulation by CST and HFSS and those of measurement for the proposed antenna.

선형 및 원형편파 특성을 갖는 5G 단말용 28 GHz 배열안테나

선형 및 원형편파 특성을 갖는 5G 단말용 28 GHz 배열안테나

2 × 2 MIMO Asymmetric U-Shaped Nonuniform Slot Antenna for the 4G LTE Metal-Housing Mobile Handsets

A 2 × 2 MIMO antenna for metal-housing mobile handset application is proposed in this article. The polarization diversity is used to arrange the two antennas’ setup. The asymmetric U-shaped nonuniform slot antenna provides two different resonant bands are designed to be operated in long term evolution (LTE) covers lower band (698 MHz to 960 MHz) and upper band (1710 MHz to 2700 MHz). The modified type III balun is used for upper-operating band, and the open stub is used for lower-operating band, good impedance bandwidth, and radiated pattern and efficiency are shown. The isolation (S21) between the antennas is more than 20 dB, and the envelope correlation coefficient (ECC) is less than 0.02. A prototype of the proposed antenna chiselling in the metal-housing mobile handset (with 160 mm in length, 10 mm in height, and 70 mm in width) is fabricated and experimentally studied.

High Gain Triple Band Microstrip Patch Antenna for WLAN, Bluetooth and 5.8 GHz/ISM Band Applications

A high gain triple bands microstrip patch antenna with modified radiating patch is proposed. Two slits and a T-shaped slot are loaded at the optimum positions on the radiating patch to enhance the number of frequency bands with high gain. A parametric study has been done to enhance the results. Three valuable frequency bands at the resonant frequencies of 4.11 GHz, 4.47 GHz, 4.86 GHz and 5.80 GHz are achieved. The achieved percentage bandwidths are 5.8%, 12.73% and 3.62%. The measured peak antenna gain of 7 dBi at 4.17 GHz is achieved. The proposed antenna may be used in mobile handset, WLAN, WiMAX and ISM band applications.

A Survey on RF and Microwave Doherty Power Amplifier for Mobile Handset Applications

This survey addresses the cutting-edge load modulation microwave and radio frequency power amplifiers for next-generation wireless communication standards. The basic operational principle of the Doherty amplifier and its defective behavior that has been originated by transistor characteristics will be presented. Moreover, advance design architectures for enhancing the Doherty power amplifier’s performance in terms of higher efficiency and wider bandwidth characteristics, as well as the compact design techniques of Doherty amplifier that meets the requirements of legacy 5G handset applications, will be discussed.

LTE and GPS based Deca Band Printed Antenna for Cellular Mobile Handset Communication Applications

This paper presents novel mobile phone antenna for radiations simultaneously in ten frequency bands for applications of LTE (Long-Term Evolution), GPS (Global Positioning System), GSM (Global System for Mobile Communications), PCS (Public and Commercial Services), DCS (Distributed Control System), UMTS (Universal Mobile Telecommunications System) and WiMAX (Worldwide Interoperability for Microwave Access). The antenna demonstrates novel characteristics for resolving the challenge of simultaneous radiation capabilities for the GSM and GPS applications with frequencies of 850/900 and 1575 MHz respectively, along with resonances at frequency band of 700 MHz for LTE applications, 1800 and 1900 MHz for PCS and DCS applications, 2100 MHz for UMTS applications, 2400 and 2500 MHz for LTE applications and 3300 MHz for WiMAX applications with S11 = - 6 dB matching criteria (VSWR 3:1). The antenna architecture comprises top and bottom copper layers embedded with monopole radiating element, branch line, slots and various stub lines. The desired operating bands are achieved in a compact area with overall dimensions of 0.8x60x120 mm for the height, width and length respectively of the antenna providing suitable platform for mobile handset applications. Omni-directional radiation pattern characteristics are achieved throughout the range of frequencies by designing the proposed antenna in monopole configuration. Proposed antenna is fabricated and results for the surface currents, s-parameters and 3D (Three-Dimensional) gain plots are illustrated for the proof of concept.

A Simple Multi-Broadband Planar Antenna for LTE/GSM/UMTS and WLAN/WiMAX Mobile Handset Applications

A simple compact low-profile multi-broadband planar antenna is proposed in this paper for LTE/GSM/UMTS and WLAN/WiMAX mobile handset applications. The proposed antenna covers multiple broad frequency bands including LTE700, GSM850, GSM900, DCS/PCS/UMTS, WLAN/WiMAX, LTE2300/2500, and LTE42/43/46. It consists of a C-shaped and U-shaped monopole on one side of a thin dielectric substrate coupled to an F-shaped strip on the other side without any lumped elements. The antenna occupies a tiny size of 15 mm $\times68$ mm $\times0.8$ mm, which makes it suitable for the popular ultra-thin smartphone applications. The antenna characteristics such as S-parameter, efficiency, peak gain, and radiation patterns are simulated by HFSS. The measured and simulated results show an excellent agreement. For more practical conditions, the antenna is stalled in a plastic housing to analyze the radiation performance. In addition, its specific absorption rate is simulated and studied by CST as well.

A frequency reconfigurable antenna for multiband mobile handset applications

A frequency-reconfigurable antenna is presented for multiband (GSM850/900/GLONASS1616/DCS1800/PCS 1900/UMTS/LTE2300/2500/WLAN) mobile handset applications. It mainly consists of radiating elements with two PIN diodes. By switching the ON/OFF states of the PIN diodes, the proposed structure can operate in three states: OFF–ON, ON–OFF, and ON–ON. When PIN diodes are in the OFF–ON states, the proposed antenna can cover the GSM850/900, PCS1900, and UMTS2100 bands by operating in Invented-F antenna (IFA) mode. When PIN diodes are in the ON–OFF states, the antenna can cover the LTE2300/2500 and WLAN2400 bands in monopole mode. Moreover, when PIN diodes are switched to the ON–ON states, the designed antenna works in loop mode and its resonant frequencies include the GLONASS1616, DCS1800/1900, and LTE2500 bands. With the reconfigurable technique, the proposed antenna achieves a compact size of 15 × 28.5 mm2 with high efficiency from 34% to 84.86% in the total frequency range.

Compact multiband antenna employing wideband dual ZOR for mobile handset applications

In this study, a compact multiband antenna employing a wideband dual zeroth-order resonator (ZOR) is proposed for mobile handset applications. The theory of wideband zeroth-order mode and multimode is used to design the proposed antenna covering LTE850/900 (824–960 MHz), LTE1700/1800/1900/2100 (1710–2170 MHz), LTE2300 (2300–2400 MHz), LTE2600 (2500–2690 MHz), and Wi-Fi (2400–2500 MHz) bands. In order to achieve wideband operations, the proposed antenna consists of a low-band ZOR and a high-band ZOR that can generate and merge resonance frequencies of zeroth-order, negative-order, and positive-order modes. The performance of the antenna is verified by both full-wave simulations and experiments. The overall size of the antenna is 40mm×6mm×3mm. The antenna provides omnidirectional radiation patterns and measured radiation efficiencies exceeding 43% and 47% for low and high bands, respectively.

Acoustic performance of MEMS microphones. Past, present, and future

An overview will be presented of the current state of commercial MEMS microphone technology with focus on acoustic performance metrics such as noise and sound pressure limits, bandwidth, and low frequency behavior. Important limitations for MEMS element and electronic performance will be discussed in the context of the various transducer technologies currently being pursued or offered. The performance of MEMS microphones, since their commercial introduction in the early 2000s, has been strongly driven by the mobile phone handset application, which continues to be the most important market segment by volume. Substantial improvements in performance have been realized since the inception, to meet opposing demands of better acoustic performance and lower power consumption/smaller size. A brief summary of the development trajectory and possible future directions will be given. With the advent of new important applications, such as home automation, and a general movement in design towards digital interfaces, other blends of microphone performance requirements are emerging. A discussion of such requirements and their possible impact on acoustic MEMS design will be provided.

A Compact Four Concentric Rectangular Rings Slot Antenna for Mobile Handset Applications

A novel compact four concentric rectangular rings slot broadband microstrip antenna is proposed for mobile handsets in the paper. The antenna has a circular radiator with four concentric rectangular rings slot structure. The antenna can cover more than ten mobile applications with -10dB bandwidth of 88.7% (1.6-4.15GH) for DCS1800(1710-1880MHz), TD-SCDMA(1880-2025MHz, 2300-2400MHz), WCDMA(1920-2170MHz, 1755-1880MHz), LTE33-41/42/43 (1900-2690MHz, 3400-3800MHz), Bluetooth, GPS, COMPASS, GLONSS, GALILEO, WLAN (802.11b/g/n:2.4-2.48GHz), and WiMAX(3.3-3.8GHz) wireless applications. The proposed antenna is fabricated on a 1.6 mm-thick FR4 substrate with dielectric constant of 4.4, and the size is 50*40mm2. The good agreement between the measurement results and the simulation validates the proposed design approach and meets the requirements for mobile handset applications.

Eight-Element Antenna Array for LTE 3.4–3.8 GHz Mobile Handset Applications

Abstract In this letter, an eight-element Multiple-input multiple-output (MIMO) antenna system for LTE mobile handset applications is proposed. The antenna array consists of eight 3D inverted F-shaped antennas (3D-IFA), and the measured –10 dB impedance bandwidth is 3.2–3.9 GHz which can cover the LTE bands 42 and 43 (3.4–3.8 GHz). By controlling the rotation of the antenna elements, no less than 10 dB isolation between antenna elements can be obtained. After using the specially designed meandered slots on the ground as decoupling structures, the measured isolation can be further improved to higher than 13 dB between the antenna elements at the whole operating band.

Radiation Characteristics by Balanced and Unbalanced Feedings of Log-Periodic Loop Antennas for Mobile Handset Applications

Radiation Characteristics by Balanced and Unbalanced Feedings of Log-Periodic Loop Antennas for Mobile Handset Applications

Planar printed loop antenna with less no‐ground space for hepta‐band wireless wide area network/long‐term evolution mobile handset

A planar printed loop antenna with hepta operating bands, which covers the GSM850/900/DCS1800/PCS1900/UMTS2100/LTE2300/2500 bands for mobile handset application, is proposed. It occupies a no-ground space of only 8 × 60 mm2 and wideband operation can be achieved by meandering or folding loop line and using matching circuits. The low frequency bands of GSM850/900 operation are achieved by the loop half-wavelength mode and matching chip capacitor, which generates a dual-resonance mode at 780 and 915 MHz. At around high frequency ranges, a one-wavelength resonant mode of the entire loop at 1.66 GHz, and high-order resonant modes of the left or the right side coupling loop are generated to cover the residual frequency bands. In addition, the proposed antenna is easily printed on dielectric surfaces of a low cost FR4 substrate, which makes it suitable for practical mobile applications. The proposed antenna is successfully simulated, fabricated, and measured comparing to simulated results to validate the design.

Compact Antenna with Frequency Reconfigurability for GPS/LTE/WWAN Mobile Handset Applications

A compact frequency reconfigurable antenna for mobile handset application is proposed in this paper. The antenna consists of an inverted L-shaped feeding strip, a shorter grounded strip, and a longer grounded strip which is connected with four inductors by using a single-pole four-throw RF switch. When we change the working states of the RF switch, the corresponding inductor is connected with the long grounded strip and different resonant modes of the antenna can be realized. The measured −6 dB impedance bandwidth of the presented antenna is 683–960 MHz and 1460–2820 MHz, which is able to cover the LTE700/GSM850/900 and GPS/DCS1800/PCS1900/UMTS2100/LTE2300/2500 bands. The antenna gain, radiation efficiency, and radiation patterns are also described in the paper.

Compact Tri-Band MIMO Antenna for LTE/GSM Mobile Handset Application

A tri-band Multiple-input-multiple-output (MIMO) antenna system for LTE 700, LTE2500 and GSM 1800/1900 mobile handset application is presented. The whole system consists of four identical 3-D IFAs (inverted F antenna) folded on FR4 cuboids. Without any special designed decoupling structures, the measured isolation among antenna elements is higher than 20dB in the low and upper bands, even in the middle band, the isolation is higher than 13.7dB. Reflection coefficient, correlation coefficient, gain and radiation pattern are also presented. Acceptable agreement between the antenna models with and without plastic housing, battery and LCD screen demonstrate that the proposed antenna is a competitive candidate for mobile handsets.

Compact Frequency Reconfigurable Antenna for LTE/WWAN Mobile Handset Applications

In this communication, a compact frequency reconfigurable antenna for LTE/WWAN mobile handset applications is proposed. The proposed antenna mainly consists of radiating elements and two PIN diodes. In addition, the antenna has a simple structure with a compact size of ${36.5} \times {10}\;\text{mm}^{2}$ . This antenna operates in six modes, and each mode is given a different resonant pathway by adjusting the bias states of two PIN diodes. When PIN diodes #1 and #2 are in the on and off states, respectively, the proposed antenna can cover the LTE700 (698–787 MHz) band by operating in mode 1. Moreover, the wide bandwidth in a higher band formed by combining modes 2 and 3 can cover the LTE2300 (2305–2400 MHz) and LTE2500 (2500–2690 MHz) bands. When PIN diodes #1 and #2 are in the off and on states, respectively, a resonant frequency in the lower band is formed by integrating modes 4 and 5. This can cover the GSM850 (824–894 MHz) and GSM900 (880–960 MHz) bands. When the two PIN diodes are in the on state, the proposed antenna can cover the GSM1800 (1710–1880 MHz), GSM1900 (1850–1990 MHz), and UMTS (1920–2170 MHz) bands in operating mode 6.

A new frequency‐reconfigurable antenna using coupling patterns for mobile handsets

ABSTRACTThis letter focuses on the design of a new frequency‐reconfigurable antenna for a mobile handset application. The proposed antenna supports the most important long‐term evolution bands: band 17 (704–746 MHz), band 13 (746–787 MHz), band 5 (824–894 MHz), and band 8 (880–960 MHz). A digital variable capacitor (DVC) is used via a coupling pattern proximity to the aperture of an inverted F antenna (IFA) to which a single‐pole single throw RF switch is connected to take advantages of the two different kinds of tuning elements. We show that the proposed antenna is able to have a quasicontinuous and wide range of frequency tuning capabilities over 700–960 MHz through simulations and experiments. We also show that the coupled aperture used for connection of the DVC to the aperture of IFA is helpful for reducing the ohmic losses in the DVC from the antenna efficiency degradation which is the most important figure of merit for frequency reconfigurable antennas based on the active tuning elements. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2333–2336, 2015