Showing papers on "GSM frequency bands published in 2017"

Tunable energy harvesting on UHF bands especially for GSM frequencies

Abstract: Metamaterial-based energy harvesting structures operating at GSM 900 and GSM 1800 frequency bands have been proposed. The basic structure is composed of four nested U-shaped elements on the front and back side of the dielectric substrate, with a 180° relationship between the front and back resonators. As energy harvesting capability is directly related to the quality of absorption, with the aim being perfect absorption, there is an air gap to allow tuning of the resonance frequency, and copper plate follows the air gap to facilitate the perfect absorption of electromagnetic waves, which is verified by means of simulation and experimental tests. A set of simulations and experimental study were further carried out to demonstrate incident and polarization angle dependency, the effects of Schottky diodes, and the optimal orientation of the U-shapes. Spectrum analysis and DC voltage measurements across the HSMS 2860 Schottky diode are also presented to test the energy harvesting capability: the spectrum analyzer shows a 40 dBm difference, while 81.7 mV maximum DC voltage is observed at 900 MHz. The simulation and experimental study results, while displaying several differences, do suggest that the proposed design can be used for running low-energy consumption devices such as sensors and switches.

A glass based dual band frequency selective surface for protecting systems against WLAN signals

Abstract: A polarization independent, double layer frequency selective surface on glass substrate is proposed that can transmit 900 MHz and 1.8 GHz GSM bands but inhibit transmission of wireless local area network (WLAN) bands, 2.4–2.5 GHz and 4.98–5.825 GHz. A parametric analysis is conducted to tailor the resonance frequencies at WLAN bands and the effect of each geometrical parameter on band stop response is investigated. Band stop responses of each FSS layer and the double layer final design are presented both numerically and experimentally. The simulation results showed a good agreement with the experimental results and supported the polarization independent behavior. In particular, very wide rejection bands are obtained (−10 dB bandwidths more than 1.75 GHz) for the 5 GHz band, both numerically and experimentally, for vertical and horizontal polarizations, under normal incidence. The design can be used in double layer window glasses for protecting systems against interference with WLAN signals in indoor environments and buildings.

Analysis of ultra wideband fractal antenna designs and their applications for wireless communication: A survey

Abstract: Due to the growth in wireless communication; the user demand for multiband, low cost, high gain, wideband and electrically small size antenna is increasing day by day. The above demands can be fulfilled by the use of Fractal geometry Antennas. In this survey, we have made the comparison of different fractal geometry antennas and techniques used for UWB applications and also observed about obtaining ultra-wideband and multiband characteristic using DGS (Defected Ground Surface), Slots, Different feeding technique and its position incorporated with fractal geometry. The above antennas are used in many wireless applications like GSM 900, GSM 1800, Bluetooth (2.4 GHz), LTE (2.3 GHz), 3G (1.92–1.98), Wi-Max (3.3, 5.3 GHz), WLAN (5.15–5.825), Satellite communication in X-band and military communication in C-band.

Design of Single-Turn Spiral Inductors With Embedding A Strong-Coupling LC Resonator for Interference Suppression

Abstract: This paper presents a study on the interference suppression effect of a resonator-embedded spiral inductor topology. In the proposed topology, a conventional single-turn spiral inductor is integrated with an embedded strong coupling ${LC}$ resonator on a printed circuit board. This ${LC}$ resonator can be designed with a specific resonant frequency near but below the operation band to achieve interference suppression by way of redirecting the magnetic flux emitted from the spiral inductor to the resonator, rather than toward the other spiral inductors outside around. In this paper, the design of interference suppression is mainly demonstrated at the LTE 700-MHz band. From the experimental results in a contrast case, the interference at 700 MHz can be depressed more than 20 dB by the proposed topology as referred to a conventional spiral inductor. The proposed topology can provide a design freedom in any interested frequency bands, such as the popular GSM bands (900/1800 MHz) or ISM bands (2.4 GHz), by changing the capacitance value of the resonator. To verify the interference suppression effect resulted from the proposed topology, electromagnetic simulations and experimental measurements in both frequency domain and time domain are conducted to provide the more in-depth view.

Design and testing of rectifying antenna for RF energy scavenging in GSM 900 band

Abstract: The energy scavenging techniques are found as sustainable solution to the increasing energy needs. The increased use of wireless devices and installation of cell phone towers in the recent years produces abundant radio frequency (RF) energy in the ambient environment. This makes the RF energy scavenging as an attractive possibility. The energy scavenging module consists of an antenna to capture RF energy and appropriate circuitry for RF to DC conversion. In the present work, a microstrip-fed printed shorted ring slot antenna with circular polarization is chosen for collecting RF energy. The bridge rectifier with Schottky diode is used for RF to DC conversion. The novelty of the work lies in the design of a highly efficient yet simple and compact rectenna module for energy harvesting in the GSM 900 band using circularly polarized antenna. The antenna structure is designed and optimized using CST microwave studio. The bridge rectifier circuit is designed using SPICE software. The measured results fo...

A survey on microstrip antennas for portable wireless communication system applications

Abstract: In modern wireless communication, microstrip antennas are widely equipped in mobiles, laptops and other portable devices due to their advantages like small size, light weight, low cost and easy integration with planar structures. Moreover, the research evolution in these antennas, which are required for portable wireless communication system applications, is advancing day by day. So, it is essential to notice the research and improvements happening in the area of microstrip antennas for the intended applications. The main objective of this paper is to discuss numerous microstrip antennas for GSM, Wi-Fi and Wi-MAX 2500 applications. The GSM applications cover GSM 900, GSM 1800 (DCS 1800) and GSM 1900 (PCS 1900) bands while the Wi-Fi applications cover 2.4GHz and 5.8GHz bands. Sometimes, these antennas also operate in various bands of GPS, LTE 2300, LTE 2600, UMTS and Wi-MAX 3500 along with the GSM, Wi-Fi and Wi-MAX 2500 bands. This paper initially presents various conventional microstrip antennas that include single, dual, triple and multi band antennas. Then, it reports frequency reconfigurable narrow band antennas and finally multi-port microstrip antennas. It also explains merits and demerits of all antenna categories. Finally, this paper helps to explore and design suitable microstrip antennas for the required applications.

Effects of detection threshold and frame size on duty cycle in GSM bands

Abstract: Explosion in the demand for mobile applications and services necessitates the efficient utilization of the limited radio spectrum Determination of a suitable detection threshold is an important aspect of spectrum occupancy measurement Inappropriate choice of the threshold value may either increase the probability of false alarm or failure detection However, the most appropriate threshold value is not yet clearly stated, though, the International Telecommunication Union (ITU) has provided a benchmark of 10 dB above the noise level as an acceptable threshold value In this paper, the effects of energy detection threshold techniques on duty cycle in the GSM bands are examined Spectrum measurements were conducted in the GSM 900 and 1800 MHz bands in Ilorin, Nigeria to cover a bandwidth of 105 MHz Experimental results based on analytical method of determining noise level (theoretical) and those obtained based on actual measurements of the noise floor (measured) were analyzed Findings indicated that the MaxNoise overestimates the occupancy values across all bands while the ITU 10 dB was found to be too conservative Therefore, for optimum prediction, 5 dB above the measured average noise level should be considered as detection threshold Furthermore, it was found that the number of frames of the sensing data do not have significant effect on the duty cycle

Comparative analysis of downlink signal levels emitted by GSM 900, GSM 1800, UMTS, and LTE base stations

Abstract: Determination of exposure levels is considered as one of the parameters of planning and optimization of green cellular networks. While moving towards 5G technology and standardization, the results of comparative exposure levels induced by 2G, 3G and 4G networks are of interest. We present the results of in-situ determination of downlink signal levels emitted by GSM 900, GSM 1800, UMTS, and LTE networks in urban areas. The measurements are conducted with calibrated spectrum analyzer NARDA SRM 3006 at outdoor and indoor spots, including LOS and NLOS positions. The highest measured value is 2.82 V/m registered in outdoor LOS position for GSM 900. The results of comparative research highlight GSM 900 as the biggest contributor to the overall cellular systems downlink signal level, followed with UMTS, GSM 1800 and LTE. Obtained results are compared with the ICNIRP reference levels as well as with downlink signal levels emitted by cellular systems in other countries.

Design optimization and implementation of multiband rectenna for efficient radio frequency energy harvesting

Abstract: Radio frequency energy harvesting has become an interesting research area in the recent years. The energy harvesting circuit called rectenna mainly consists of an antenna and rectifier. In this paper an empirical rectenna model is designed for energy harvesting in the GSM900, 1800 band as well as 2.4GHz ISM band. A triple band symmetrical arm dipole antenna with seven stage voltage multiplier is usedto improve the overall efficiency. The measured results for prototype rectenna show good matching with the simulated results. The maximum efficiency of 32.5% is obtained for very low incident power density (e.g. ∼25μWatt/m2) in the GSM 900 band.

An octahedron shaped planar antenna for IoT applications

Abstract: In this paper, a novel coplanar waveguide (CPW) fed truncated octahedron shaped antenna is proposed, which operates over the triple RFID bands of 858 MHz-930 MHz, 2.4–2.454 GHz, and 5.725 GHz-5.875 GHz at UHF, Microwave and SHF frequency bands in addition to the LTE-700 MHz, LTE-800 MHz, GSM 850 MHz, GSM 900 MHz, TV broadcasting, and 5G bands of the electromagnetic spectrum. The antenna is experimentally verified for its radiation characteristics, UHF RFID detection, and GSM 900 MHz connectivity.

Design and development of dual-band multi-stage RF energy harvesting circuit for low power applications

Abstract: This paper presents the design and development of a dual-band multi-stage rectifier aimed at converting far field RF energy into DC voltage at low received power. The designed RF energy harvester consists of a dual-band matching network followed by a 3-stage rectifier which has been designed to work in GSM 900 MHz and Wi-Fi/Wireless LAN (WLAN) bands. It provides a peak conversion efficiency of 80% at 8 dBm received RF power at 915 MHz. The experimental results also show that the proposed dual-band rectifier can harness twice amount of power than single band 915 MHz rectifier. This work further utilizes the above circuit to obtain preliminary results of RF energy harvesting through mobile phones. Mobile phones from two different manufacturers have been used to evaluate the output DC voltage levels obtained through energy harvesting. Measurements were taken during call-establishment phase as well as during call-conversation phase. It was shown that depending on the manufacturer, it is possible to obtain peak average voltages of 1 volt and 0.25 volt in call-establishment phase and call-conversation phase respectively. The prototype has been fabricated on RT/Duroid 5880 substrate and all the simulations have been performed on Advanced Design System (ADS).

Effect of GSM Frequency Band on Received Signal Strength and Distance Estimation from Cell Tower

Abstract: This work intends to analyse the relationship of a particular GSM frequency band with the received signal strength (RSS) on a receiving mobile device This work has shown that there is a significant relationship between frequency and RSS values Thus no one particular algorithm can be used to co-relate signal strength to distance without factoring in the frequency band The signal and attenuation channel has been simulated for the various frequency bands and distances This work is based on the assumption that the propagated signal is on a static frequency and that advanced fading inhibition techniques like frequency hopping are not in use A path-loss model has been implemented on the different downlink frequency and the respective received RSS values against distance plotted

On -vehicle receiving antenna of big dipper GPS

Abstract: The utility model discloses an on -vehicle receiving antenna of big dipper GPSGSM, including antenna main part, antenna array, signal transmission line, the coaxial symmetry of antenna array sets up in the casing both sides of antenna main part, and the line length between the both ends in the antenna array outside is the fourth of GSM frequency wavelength, signal transmission line perpendicular to antenna array axial sets up, and wherein, antenna array includes copper post, spring, and the one end of copper post sets up draw -in groove and back -off, and the spring is fixed through the back -off in emboliaing the draw -in groove, the GSM antenna includes antenna array, signal transmission line, and antenna array symmetry sets up in antenna shell's both sides, and signal transmission line and antenna array are connected. The problem of two antennas increase the space -occupying volume, lead to the wiring construction complicated is solved, eliminated and come fixed drawback with the welding between copper post and the spring, and can exert the effect of big dipper GPS antenna and GSM antenna simultaneously, reduced space and mould utility.

Multi-Band Microstrip Antenna Design for Mobile Phone Applications

Abstract: Multi band antenna with miniature volume is of more requests for the ever growing wireless communication industry. In this paper, a double-layers and five-bands of microstrip patch antenna is designed. The S-parameter as well as radiation pattern are investigated. On the other hand, the proposed antenna is suggested to be employed in a handset mobile phone that covers five frequency bands as follows; GSM 900 (889– 960) GSM 1800 DCS 1800, (1710–1885)W-CDMA (Wideband Code Division Multiple Access), IMT 2000 (International Mobile Telecommunication)1885–2200, Wi-Fi/WLAN (IEEE 802.11 b/g/n) ISM 2450 (Industrial, Scientific and Medical) (2400–2500) and WiMax (Worldwide Interoperability for Microwave access) which have been established by the IEEE 802.16 working group. The proposed square patch antenna has been gained return loss of −33dB at 2.0924 GHz, −25dB at 2.67 GHz, −20.5 dB at 1.745 GHz and −20dB at 2.44GHz and −18dB at 0. 94GHz frequencies. Design and simulation of the presented structure was based on CST software package. Finally, five frequency bands are produced and the antenna shows encouraged results for WLAN applications.

FDTD Based SAR Analysis in Human Head using Irregular Volume Averaging Techniques of Different Resolutions at GSM 900 Band

Abstract: Specific Absorption Rate (SAR) induced inside human head in the near-field of a mobile phone antenna has been investigated for three different SAR resolutions using Finite Difference in Time Domain (FDTD) method at GSM 900 band. Voxel based anthropomorphic human head model consists of different anatomical tissues is used to calculate the peak SAR values averaged over 10-g, 1-g and 0.1-g mass. It is observed that the maximum local SAR increases significantly for smaller mass averages.

Design of triple starfish shaped microstrip patch antenna for IoT applications

Abstract: A triple Starfish shaped Microstrip patch antenna with microstrip line feed for IoT application is introduced in this work. The antenna is active over the frequency bands of 0.62GHz-0.96GHz, 2.34GHz-2.46GHz, 3.13GHz-3.31GHz, 4.73GHz-5.03GHz, 5.68GHz-5.92GHz. The S n = −10 dB impedance bandwidth is 340MHz (0.62GHz-0.96GHz), 120MHz (2.34GHz-2.46GHz), 180MHz (3.13GHz-3.31GHz), 300MHz (4.73GHz-5.03GHz), 240MHz (5.68GHz-5.92GHz) in different bands. The FR4 material of dielectric constant 4.4 and loss tangent 0.02 is chosen as the substrate of the antenna. The antenna operates in the frequency ranges of Bluetooth, WiFi, and WiMAX and enables the IoT applications. As well as it can works in the range of GSM 900 band for cellular applications.

A compact tri-band antenna for GPS and GSM applications

Abstract: A compact tri-band antenna is presented in this paper for GSM 900/1800 and GPS applications. The proposed antenna is constructed by two stacked structures, one is a microstrip square ring patch with truncate corners for GPS L1 band, the other is two nested small loops with a multistage matching network composed of lumped components and shorting pins for GSM 900 and 1800 bands, respectively. The dimension of the antenna is 60 × 60 × 12 mm3. Simulation results indicate that the antenna radiates omnidirectional pattern with vertical polarization at GSM 900/1800 bands, and broadside pattern with right-hand circular polarization at GPS L1 band. Finally, a prototype of the antenna is fabricated and measured, whose measurement results meet well with the simulation results.

Design, simulation, and fabrication of broadband inkjet-printed log-periodic antennas

Abstract: We present design and computational analysis of log-periodic antennas that are fabricated by using low-cost inkjet printing technology. The designed antennas operate in the 1.5–2.5 GHz range and are suitable for diverse applications, including energy harvesting at WiFi and GSM bands. Suitable designs are fabricated by using silver-based inks in standard commercial printers. Despite the challenges in both design and fabrication processes, we demonstrate log-periodic antennas with desired operating properties at the target frequencies. Details of the design procedures, parametric analysis, as well as simulation and measurement results are presented.

A 3D printed dual GSM band near isotropic on-package antenna

Abstract: In this paper, we propose an on-package dual band monopole antenna with near-isotropic radiation pattern for GSM mobile applications. The proposed antenna is well matched for both GSM 900 and 1800 bands and provides decent gain for both the bands (1.67 and 3.27 dBi at 900 MHz and 1800 MHz respectively). The antenna is printed with silver ink on a 3D printed polymer based package. The package houses the GSM electronics and the battery. By optimizing the antenna arms width and length, a near-isotropic radiation pattern is achieved. Unlike the published isotropic antennas which are either single band or large in size, the proposed antenna covers both GSM bands with required bandwidth and is only half wavelength long. The design is low cost and highly suitable for various GSM applications such as localization, in additional to conventional communication applications.

GSM (Global System for Mobile Communications) mobile phone voice monitoring method

Abstract: The invention discloses a GSM (Global System for Mobile Communications) mobile phone voice monitoring method. The method comprises the following steps of S1, collecting and processing air interface data of GSM frequency points and searching and synchronizing a plurality of GSM cells; S2, monitoring a control channel, detecting a signal message, obtaining a mobile subscriber identity, an encryption mode, an opposite end number, a business channel parameter, a signal and cell switching parameter and a signal release indicator; and S3, monitoring a business channel to obtain voice content. According to the method, the independent voice monitoring can be carried out on special target mobile phones within a plurality of surrounding GSM cell ranges, and extensive monitoring can be carried out on all mobile phones within the plurality of surrounding GSM cell ranges.

Multi-mode terminal, CSFB realization method and GSM adjacent region information sheet maintenance method

Abstract: The invention provides a multi-mode terminal, and a CSFB voice business realization method; the multi-mode terminal reads system messages of a plurality of GSM adjacent regions under a LTE idle state, and obtains signal intensity satisfying residence conditions and each community location area ID according to the system messages, thus building a GSM adjacent region information sheet; the multi-mode terminal switches to the GSM network and carries a GSM frequency point list, carries out frequency sweeping, and preferably selects a GSM community as the candidate community according to the signal intensity obtained by frequency sweeping and the GSM adjacent region information sheet, wherein the selected community satisfies residence conditions, the system message of the selected community is read, and the selected community has the same ID with a residence LTE community location area ID; the multi-mode terminal returns to the selected community from the LTE mode to reside, and starts a calling process. The multimode terminal and the method can omit a residence GSM community system message reading process and a location area updating process, thus reducing calling delay. The invention also provides the GSM adjacent region information sheet maintenance method so as to timely update the information in the information sheet.

Differential Dickson voltage multiplier with matching network for radio frequency harvester

Abstract: This paper presents the design and implementation of the differential Dickson voltage multiplier with a matching network which is used in the radio frequency (RF) energy harvester at GSM frequency band. The proposed RF energy harvester consists of a matching network and a Dickson rectifier. Those circuits are designed and simulated with standard TSMC 0.18 µm 1P6M CMOS process. The matching network is used not only to obtain the maximum power deliver from antenna to the RF-DC rectifier, but also to have the maximum conversion efficiency. In the proposed differential Dickson voltage multiplier, a native MOSFET is considered in implementing the multiplier with low threshold voltage, and a modified Dickson voltage multiplier with differential schematic is used to enhance the performance of the Dickson voltage multiplier. According to the simulated results, the conversion efficiency, input return loss, and output voltage are 28.83%, −47.285 dB, and 1.5 V, respectively, at a load impedance of 239 kΩ, an input power of −10 dBm, and in GSM frequency band.

Design of Fractal Array Bionic Ultra Wideband Antenna

Abstract: According to the requirements of the second generation, the third generation, the fourth generation and the fifth generation mobile communication system, radio frequency identification system and ultra wideband communication system to the antenna's performance, the present paper originally combines bat wing bionic antenna and cross fractal array, designed a fractal array bionic ultra wideband antenna, fabricated the antenna sample and tested the radiation characteristics of the antenna. The result of test indicate that the antenna's working frequency range is 0.728-12.739 GHz, the antenna's working bandwidth is 12.011 GHz, the bandwidth octave is 17.49, the antenna return loss is less than -10 dB in the whole operating frequency band, the minimum value of return loss is -23.18 dB. This antenna completely covered the second generation mobile communication standard GSM frequency band, the third generation mobile communication standard TD-SCDMA frequency band, the third generation mobile communication standard WCDMA frequency band, the fourth generation mobile communication standard TD-LTE frequency band, the three candidate frequency bands of the fifth generation mobile communication, the three common frequency bands of the radio frequency identification system , and working band of ultra wideband communication system. This antenna can meet the requirements of small size, low thickness, low return loss and wide working bandwidth at the same time, it has a broad application prospect.

Car oil -break protection device

Abstract: The utility model provides a car oil -break protection device, it includes wired protector host computer and oil circuit protector, the oil circuit protector receives the control of wired protector host computer, wired protector host computer includes MCU1 main control chip, GSM frequency channel intensity detection module, GPS frequency -conversion circuit, GSM GPRS communication module, GPS orientation module and wireless communication module, MCU1 main control chip respectively with GSM frequency channel intensity detection module GSMGPRS communication module with wireless communication module electric connection, GSM frequency channel intensity detection module respectively with MCU1 main control chip with GPS frequency -conversion circuit electric connection, GPS frequency -conversion circuit with GSM frequency channel intensity detection module electric connection, GSMGPRS communication module respectively with MCU1 main control chip with GPS orientation module electric connection, GPS orientation module with GSMGPRS communication module electric connection, wireless communication module with MCU1 main control chip electric connection.

Enhanced bandwidth PIFA antennas for 900/1800 MHz and WiFi 2400 MHz band with a dielectric cover

Abstract: This paper is dedicated to the development of PIFA antennas with a dielectric cover for different frequency bands. A PIFA antenna on FR-4 with ∊ = 4.4 and thickness h = 2 mm was simulated, manufactured and tested for use with the GSM 900/1800 MHz transceiver. On the same substrate, an antenna for Wi-Fi (2.4 GHz) was designed. For antennas, regions of 65 by 10 and 45 by 10 millimeters respectively were allocated. The antennas have a double-layered cover made of polyethylene and polyurethane with dielectric constants of 1.2 to 1.5 and 6 to 8 respectively.

An Extended-AMATA Indoor Propagation Model for GSM 900/1800 MHz and Wi-Fi 2.4 GHz Frequencies

Abstract: In a previous article, we reported on a novel indoor propagation model; we called the AMATA model, which we applied at 900 MHz and 2.4 GHz frequencies. The model could be applied at both GSM and wireless LAN frequencies. The developed formula merits, on its own, as a novel fourth power effective attenuation equation, which relies on the number of wall separations within the floor. This paper reports an extended-AMATA indoor propagation model that generally describes university and office type buildings. A sample of four different multi-floor building structures that have a stone block type outer wall was chosen. Those flat roofed, stone built, multi floor buildings are very common, not only in Palestine, but probably in vast areas in the Middle East region. The new model benefits over the previous one, applied at 900 MHz, in that it can be extended to cellular base-stations, transmitting at 1800 MHz frequency and outdoor Wi-Fi basestations, as opposed to indoor access points, transmitting at 2.4 GHz. The work is of paramount importance to cellular and Wi-Fi network operators, transmitting at 900/1800 MHz and 2.4 GHz frequency bands. Our new model can be applied with a high confidence level to buildings, similar to the sample of buildings, we measured.

Compact ultra-wideband PIFA antenna for high performance mobile devices

Abstract: A planar inverted-F antenna (PIFA) with a very wideband that begins in 690 MHz and ends in 12.91 GHz is presented. This large wideband is achieved within the size restrictions imposed to some types of mobile devices and the additional advantages of high efficiency and very acceptable reflection coefficient. With this ultra-wideband the PIFA proposed is able to work correctly in every one of the 52 frequency bands specified for the LTE services, except 450 MHz. In this way, the antenna can work properly in many important bands such as LTE 700, GSM 800, GSM 900, DCS, PCS, AWS, WiFi, Bluetooth and the segment of 3.1–10.6 GHz for Ultra-Wideband services.

Control method and device for startup registration network of mobile terminal

Abstract: The invention discloses a control method for a startup registration network of a mobile terminal. The control method for the startup registration network of the mobile terminal comprises the steps of when the mobile terminal starts up, searching the network, sorting the searched network in various frequency bands according to signal strength to perform networking registration; when the network frequency band to be registered is determined, judging whether the network frequency band to be registered is the GSM frequency band; when the network frequency band to be registered is the GSM frequency band, judging whether the network frequency band to be registered is the pseudo base station frequency band; if yes, re-determining the network frequency band to be registered according to a sort order of the signal strength; and if no, initiating position update registration to a base station corresponding to the network frequency band to be registered. The invention also discloses a control device for the startup registration network of the mobile terminal. According to the method and the device provided by the invention, use security of the mobile terminal under the condition of accessing the GSM network for communication during a startup process is improved.