GSM Bands Research Articles

Specific absorption rate analysis of broadband mobile antenna with negative index metamaterial

This paper presents a negative index metamaterial-inspired printed mobile wireless antenna that can support most mobile applications such as GSM, UMTS, Bluetooth and WLAN frequency bands. The antenna consists of a semi-circular patch, a 50Ω microstrip feed line and metamaterial ground plane. The antenna occupies a very small space of 37 × 47 × 0.508 mm3, making it suitable for mobile wireless application. The perceptible novelty shown in this proposed antenna is that reduction of specific absorption rate using the negative index metamaterial ground plane. The proposed antenna reduced 72.11 and 75.53 % of specific absorption rate at 1.8 and 2.4 GHz, respectively.

Dual-band reflectarray with crossed-dipole elements for GSM and LTE applications

A novel dual-band reflectarray for beam control of reflected waves at GSM and LTE bands is proposed in this paper. The reflectarray is constructed with two substrates separated at a distance form. Consisting of square ring and four stubs, the FSS cell element has the dual-band property for the changes of current distribution. A crossed-dipole element is printed on the surface of another substrate, and the progressive phase distribution is achieved for the reflected wave by adjusting the resonant length of the crossed-dipole element. The reflectarray can independently control the direction of both horizontally and vertically polarized reflect beams at two resonant frequencies. A reflectarray comprising 7 by 5 elements with operation at 1.7GHz and 2.7GHz is studied and measured, which can be applied in the GSM and LTE communication systems.

A Frequency Tunable High Sensitivity H-Field Probe Using Varactor Diodes and Parasitic Inductance

A frequency-tunable resonant magnetic field probe is designed for near-field scanning applications for the radio frequency interference studies. Tunable resonance is achieved by using a varactor diode providing the required capacitance and the parasitic inductance of a magnetic loop (i.e., a parallel LC circuit). An equivalent circuit model for the probe is described, analyzed, and used for designing the probe for achieving maximum sensitivity. The resonance frequency of the designed probe is tunable in the frequency range of 900–2260 MHz that covers multiple radio bands, such as the GSM900, UMTS, and GPS bands. The sensitivity of the probe at the resonance frequency is about 7–9 dB higher than that of an equivalently sized broadband magnetic field probe throughout the tunable frequency range. The measured frequency response and sensitivity over a microstrip trace using the fabricated probe shows good agreement with the simulated results of the equivalent circuit model and the full-wave simulation model.

Dual-Band Balanced Bandpass Filter With Common-Mode Suppression Based on Electrically Small Planar Resonators

The design of fully planar dual-band balanced bandpass filters with common-mode noise suppression is reported. The proposed filters are based on electrically small resonators coupled through admittance inverters. For design purposes, the circuit models of the considered resonators are reported. The key aspect for selective mode suppression (i.e., common-mode rejection in the differential-mode pass bands) is related to symmetry properties. Thus, for the differential-mode the symmetry plane is an electric wall, and the equivalent circuit for that mode provides dual-band functionality. Conversely, for the common-mode the symmetry plane is a magnetic wall, and the equivalent circuit exhibits a rejection band. As a proof of concept, the design of an order-2 Chebyshev dual-band balanced bandpass filter with center frequencies $f_{1} = 1.8$ GHz (GSM band) and $f_{2}= 2.4$ GHz (Wi-Fi band), fractional bandwidth $FBW = 7 \%$ , and ripple level $L_{Ar}= 0.01$ dB is reported.

Wideband Monopole Antenna With Less Nonground Portion For Octa-Band WWAN/LTE Mobile Phones

An octa-band WWAN/LTE monopole antenna with a size of $80\,\text{mm} \times 8\,\text{mm} \times 5.8\,\text{mm}$ for 5.7-inch mobile phones is proposed and studied. The proposed antenna consists of a folded metal plate with a lumped-element high-pass matching circuit. The working mechanism is analyzed based on the S-parameters and the surface current distributions. The 0.25-wavelength, 0.5-wavelength, and 1-wavelength modes of the monopole antenna are excited and used. The attractive merit of the proposed antenna is that the height of the nonground portion is only 8 mm. A prototype is fabricated and measured. Its measured $-6\;\text{dB}$ impedance bandwidths are 290 MHz (0.69–0.98 GHz) and 1.11 GHz (1.63–2.74 GHz) which cover the LTE700, GSM850, GSM900, GSM1800, GSM1900, UMTS, LTE2300, and LTE2500 bands. Within the two frequency bands, good radiation performances are obtained.

A COMPACT QUAD-BAND BANDPASS FILTER USING MULTI-MODE STUB-LOADED RESONATOR

This paper presents a compact shorted stub-loaded quad-band bandpass filter. The proposed filter simultaneously operates at GSM (0.83-0.97 GHz), LTE2300 (2300-2400 MHz), WiMAX (3.3-3.7 GHz), and WLAN (5.725-5.825 GHz) bands. The filter has been designed using the technique of stub-loaded resonator (SLR). By changing the length of the center-loaded stub, the resonant frequency of the even-mode can be varied without affecting that of the odd-mode. This simplifies the design and tuning of the quad-band filter. Eight transmission zeros (TZs) around the three passband make the pass bands highly isolated. In order to validate its practicability, a quad-band bandpass filter (BPF) has been designed, fabricated and measured. Good agreement between simulated and measured results is observed.

A Design Approach of GSM, Bluetooth and Dual band Notched UWB Antenna

In this paper, printed GSM Bluetooth dual band notch UWB antenna is presented. In this prototype corner cut patch for Bluetooth application and dual band notch characteristics of UWB antenna perform by inverting USlot in the radiation patch of antenna. With the enclosing of λ/4 stub in the patch of antenna for GSM (1.7101.885 GHz) band operation. Simulation results show that the antenna yields an impedance bandwidth of 2.42.48 and 3-11 GHz with -10 dB reflection coefficients, except for the dual notched bands of 3.3-3.7 for WiMAX and 5.15-5.825 GHz for WLAN. The electrical characteristics in frequency domain show suitability of this antenna for use in UWB systems.

Do car-mounted mobile measurements used for radio-frequency spectrum regulation have an application for exposure assessments in epidemiological studies?

Knowing the spatial and temporal trends in environmental exposure to radiofrequency electromagnetic fields is important in studies investigating whether there are associated health effects on humans and ecological effects on plants and animals. The main objective of this study is to assess whether the RFeye car-mounted mobile measurement system used for radio frequency spectrum monitoring in The Netherlands and the United Kingdom could be of value in assessing exposure over large areas as an alternative to measuring exposure with personal exposure meters or using complex modelling techniques. We evaluated the responses of various body-worn personal exposure meters in comparison with the mobile measurement system for spectrum monitoring. The comparison was restricted to downlink mobile communication in the GSM900 and GSM1800 frequency bands. Repeated measurements were performed in three areas in Cambridge, United Kingdom and in three areas in Amersfoort, The Netherlands. We found that exposure assessments through the car-mounted measurements are at least of similar quality to exposure modelling and better than the body worn exposimeter data due to the absence of the shielding effect. The main conclusion is that the mobile measurements provide an efficient and low cost alternative particularly in mapping large areas.

Compact Multiband Antenna for Handsets With a Conducting Edge

This communication proposes a compact multiband antenna fed by microstrip coupling for handsets with conducting edge applications. The antenna is composed of a U-shaped loop, an inserted open-end T-shaped slot, and a feed line with a compact antenna area. Three types of resonant modes are excited, namely loop mode, slot mode, and monopole mode. Parametric studies have been performed. After the related parameters are controlled, the bandwidth of this antenna has the potential to cover the mobile bands of GSM (824–960 MHz), DCS (1710–1880 MHz), PCS (1850–1990 MHz), UMTS (1920–2170 MHz), LTE bands (FDD–LTE bands 1–10, 15, 16, 18–20, 22, 23, 25–27, and 30 and TDD–LTE bands 33–43). Good radiation characteristics, such as gain and radiation efficiency, are obtained with these operating bands. In addition, the structure of the inserted slot antenna reduced the user’s hand effects on the radiation efficiency.

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.

Design and Fabrication of Duplexer for GSM900 Band Applications

Design and Fabrication of Duplexer for GSM900 Band Applications

Dual Band Circularly Polarized Monopole Antenna Design for RF Energy Harvesting

ABSTRACTThis paper presents the design of a multiband microstrip monopole antenna with circular polarization and impedance 377 Ω for radio frequency energy harvesting in the CDMA (869–890 MHz) and GSM (935–960 MHz, 1810–1880 MHz) bands. The antenna structure is simulated using electromagnetic software Computer Simulation Technology (CST) transient solver. The parametric study on the antenna dimension is conducted to achieve 10 dB return loss bandwidth and 3 dB axial ratio bandwidth over the desired frequency ranges. The gain of the antenna varies from 3.5–4 dBi over the impedance bandwidth. The experimental results for prototype antenna show well agreement with the simulated results.

A Double-Negative Metamaterial-Inspired Mobile Wireless Antenna for Electromagnetic Absorption Reduction.

A double-negative metamaterial-inspired antenna is presented for mobile wireless applications. The antenna consists of a semi-circular radiating patch and a 3 × 4 hexagonal shaped metamaterial unit cell array in the ground plane. The antenna is fed with a 50 Ω microstrip feed line. The electric dimensions of the proposed antenna are 0.20λ × 0.26λ × 0.004λ, at the low-end frequency. The proposed antenna achieves a −10 dB impedance with a bandwidth of 2.29 GHz at the lower band and 1.28 GHz at the upper band and can operate for most of the mobile applications such as upper GSM bands, WiMAX, Bluetooth, and wireless local area network (WLAN) frequency bands. The focused novelties of the proposed antenna are its small size, multi-standard operating bands, and electromagnetic absorption reduction at all the operating frequencies using the double-negative metamaterial ground plane.

A Multi-Band Trident Shape Microstrip Patch Antenna for GSM and Wide Band Application

A Multi-Band Trident Shape Microstrip Patch Antenna for GSM and Wide Band Application

An on‐wafer embedded passive device using chip‐in‐substrate packaging technology

ABSTRACTIn this article, a new packaging technology called chip‐in‐substrate packaging (CiSP) technology, which embeds passive components such as inductors and capacitors on silicon substrates, is arranged for a three‐dimensional structure. As the parasitic capacitance of the inductors and capacitors are increased by CiSP, a lower self‐resonance frequency compared with bare chips can be avoided using a printed circuit board with low thickness and low permittivity. To verify CiSP on the circuit level, a diplexer circuit is simulated from measured components and is composed of two series LC resonators to apply a GSM band (880–960 MHz) and a DCS band (1.71–1.88 GHz). An insertion loss of 0.76 dB at 0.96 GHz for GSM and 0.772 dB at 1.71 GHz for DCS are realized by CiSP technology. Moreover, the minimum rejections of 19.1 dB at 1.71 GHz for GSM and 20.8 dB at 0.96 GHz for DCS are realized with the maximum rejections for the DCS and GSM bands of 37.6 and 33.7 dB, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2060–2067, 2015

Specific absorption rate reduction of multi‐standard mobile antenna with double‐negative metamaterial

A printed multi-standard mobile wireless antenna loaded with double-negative metamaterial that achieves an impedance bandwidth of 2.29 GHz (1.66 to 3.95 GHz) and 1.28 GHz (4.45 to 5.73 GHz) is presented. The proposed antenna can operate in the frequency bands of GSM (1800, 1900, 2100), WiMAX (3.2–3.6 GHZ), WLAN, Bluetooth (2.4 GHz) and WLAN (5.47–5.9 GHz). The antenna is assimilated with a semi-circular shape radiating patch, a metamaterial loaded ground plane and a 50 Ω microstrip feed line. The antenna exhibits a planar structure and occupies a very small space of 37 × 47 × 0.8 mm3, making it suitable for mobile wireless applications. The perceptible novelties exhibited in this proposed antenna is reduction of electromagnetic absorption with the metamaterial loaded ground plane. The proposed metamaterial antenna achieved 66.47 and 66.52% of 10 g specific absorption reduction at 1.8 and 2.4 GHz, respectively.

A dual‐band compact printed monopole antenna using multiple rectangle‐shaped defected ground structures and cross‐shaped feed line

ABSTRACTA compact printed monopole antenna with dual‐band operation at 1.8 GHz (GSM Band) and 5.2 GHz (Wi‐Fi Band) is presented. The antenna consists of a modified U‐shaped radiating patch with a triple rectangular defect in the ground plane. The antenna is fed by a cross‐shaped feed line, which helps in realizing the dual‐band operation. The antenna has been designed using RO4350 substrate. The design size achieved is 19 × 28 mm2. An impedance bandwidth of about 32% at 1.8 GHz and about 29% at 5.2 GHz for 10 dB return loss has been achieved. A size reduction of about 12% in comparison with a similar antenna without defected ground structures has been achieved. The proposed antenna has been fabricated and tested, and a good agreement between simulated and measured results is seen. Acceptable E‐plane and H‐plane radiation patterns have been observed through simulations, and a peak antenna gain of about 2.8 dBi has been achieved. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1810–1813, 2015

A Multi-Band Stacked RF Energy Harvester With RF-to-DC Efficiency Up to 84%

The aim of this paper is to show the possibility to harvest RF energy to supply wireless sensor networks in an outdoor environment. In those conditions, the number of existing RF bands is unpredictable. The RF circuit has to harvest all the potential RF energy present and cannot be designed for a single RF tone. In this paper, the designed RF harvester adds powers coming from an unlimited number of sub-frequency bands. The harvester's output voltage ratios increase with the number of RF bands. As an application example, a 4-RF band rectenna is designed. The system harvests energy from GSM900 (Global System for Mobile Communications), GSM1800, UMTS (Universal Mobile Telecommunications System) and WiFi bands simultaneously. RF-to-dc conversion efficiency is measured at 62% for a cumulative -10-dBm input power homogeneously widespread over the four RF bands and reaches 84% at 5.8 dBm. The relative error between the measured dc output power with all four RF bands on and the ideal sum of each of the four RF bands power contribution is less than 3%. It is shown that the RF-to-dc conversion efficiency is more than doubled compared to that measured with a single RF source, thanks to the proposed rectifier architecture.

접지에 둘러싸인 휴대폰을 위한 6중 밴드 하이브리드 MIMO 안테나

본 논문에서는 6중 이동통신 대역을 만족하는 단말기용 PIFA(Planar Inverted F Antenna) + IFA(Inverted F Antenna) 하이브리드 MIMO(Multi Input Multi Output) 안테나를 설계하고, 이를 구현하였다. 커플링 급전구조를 이용하여 PIFA와 IFA가 동시에 동작하도록 함으로써 접지 면이 많은 현재의 스마트폰에 효과적으로 적용될 수 있도록 시도하였다. 후면이 접지인 부분에는 PIFA를 설계하였고, 접지가 없는 휴대폰 상단 작은 공간에는 IFA를 설계하였다. 안테나는 폰과 동일한 크기로 carrier가 없는 PCB embedded로 대각선 급전 MIMO 안테나로 구현하였다. 베어보드에 구현된 안테나는 CDMA, GSM900, DCS, KPCS, USPCS, WCDMA의 6중 이동통신 서비스 대역에서 VSWR 3 : 1 이하의 특성을 만족하였다. 평균이득과 효율은 CDMA, GSM900대역에서 -5.19~-3.16 dBi 및 30.27~48.26 %를 보였다. 또한, DCS, KPCS, USPCS, WCDMA 대역에서는 -9.50~-5.19 dBi의 평균이득과 11.23~30.28 %의 효율특성을 가짐으로써 휴대폰 안테나로 적용될 수 있음을 보였다. In this paper, we designed and implemented a PIFA(Planar Inverted F Antenna) + IFA(Inverted F Antenna) hybrid MIMO(Multi Input Multi Output) antenna for the hexa mobile communication service band. By the simultaneous operation both PIFA and IFA using the coupled feeding structure, we tried for application to modern mobile phones that have large ground size. A PIFA is applied to the ground area, and an IFA is applied to no ground small space on top of the phone. A diagonal fed MIMO antenna is implemented PCB embedded type without antenna carrier component. Implemented antenna on the bare board measured within 3 : 1 for VSWR under hexa mobile communication band as CDMA, GSM900, DCS, KPCS, USPCS, and WCDMA. Measured average gains and efficiencies were -5.19~-3.16 dBi and 30.27~48.26 % for the CDMA, GSM900 band, and -9.50~-5.19 dBi and 11.23~30.28 % for the DCS, KPCS, USPCS, WCDMA band. It's shown that studied antenna can be applied to the antenna for the modern mobile phone.

CSRR‐based compact penta band printed antenna for GPS/GSM/WLAN/WiMAX applications

ABSTRACTThis article describes the design of a compact penta band triangular patch antenna backed by a hexagonal complementary split ring resonator operating in the GPS (1.57 GHz), GSM (1.80 GHz), WLAN (2.4/5 GHz), and WiMAX (3.5 GHz) bands. The antenna has a very compact dimension of 20 × 20 × 1.6 mm3. Three concentric hexagonal split ring slots in the ground plane yield the uppermost triple bonds (2.45, 3.5, 5.2 GHz) and the two parameterized radiating branches attached to the triangular patch accounts for the two lowermost operating bands (1.57, 1.8 GHz). A prototype of the proposed antenna is fabricated and tested. Simulated and measured results are in good agreement. It has a uniform radiation pattern over all the operating frequencies and a peak gain of 6.3 dBi at 3.5 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1538–1542, 2015