GSM frequency bands

About: GSM frequency bands is a research topic. Over the lifetime, 559 publications have been published within this topic receiving 5067 citations.

Integrated dual band GSM microstrip monopole using GA and FDTD

Abstract: By combining GA with FDTD, integrated multiband antenna designs can be generated at arbitrary frequencies of interest. These antennas designs can use an arbitrary shape. This paper presents the optimized design of a dual band GSM microstrip monopole antenna. It is impedance matched extremely well in the GSM frequency bands of 890-960 MHz and 1850-1990 MHz and the return loss is less that -20 dB at all frequencies in the bands of interest. The antenna shows an extremely flat radiation pattern, with small dimensions which show the ability of the GA to utilize available space to create a compact and relatively broadband antenna.

Multi-band Antenna with Minimalization of Radiation towards Head

Abstract: Intensive development of cellular personal communications system has been ob- served lately. Thus, protection of a man, and especially protection of his head against non-ionizing electromagnetic radiation generated by cellular telephones is becoming one of the most important problems. The results of elaborated microstrip antennas which have minimized radiation towards the user's head are presented in this paper. 1. INTRODUCTION Wireless communication has been the fastest growing sector of telecommunication in recent years. Substantial contributions to this growth has been made in Europe, where many such systems have been developed: GSM (Global System for Mobile Communication), operating in the 900MHz band, DCS-1800 (Digital Personal Communication System), using the 1800MHz band DECT (Digital Eu- ropean (Enhanced) Cordless Telecommunications, using the 1900MHz band and UMTS (Universal Mobile Telecommunications System) working in band circle about 2GHz. Some experts predict that by the end of new century there will be more cordless than conventional telephones in use. In order to achieve an easy access to information, more and more modern cellular phones, which are able to work in two or three bandwidths, are being invented. This is why it is important to determine possible health efiects of using such devices. New trends require antennas to be cheap to produce and to meet tough operational requirements. The following requirements should be met by the antenna: † a radiation pattern ensuring reliable communication regardless of the antenna's orientation; † a wide operational frequency band, so that the spectrum of transmitted information should not be distorted; † a minimum impact on the biological tissue of the user, to avoid health risks; † little sensibility of the antenna parameters to the user's proximity; † small size to facilitate mounting the antenna and using the telephone. It is clear that some of these requirements are mutually exclusive, so a compromise has to be worked out in the designing process. 1m GSM 900 (0.8W) Class 5 0.386W/m 2 0.09W/m 2 0.1W/m 2 GSM 900 (2W) Class 4 1.06W/m 2 0.26W/m 2

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.

Perencanaan ulang site jaringan gsm 900 dan 1800 di kota semarang

Abstract: Global System for Mobile Communication (GSM) is designed to provide solutions for high increasing number of subscribers of mobile communication services, while the frequency resources is limited. GSM is a digital cellular communication technology with a coverage service area is divided into small areas called cells, and each cell is handled by a site. To anticipate the growth of users number GSM system requires site re-planning that consist of three aspects, namely capacity, coverage and quality. With this site re-planning the number of site eficiency is expected. This paper has made simulation re-planning for an outdoor coverage site system of GSM radio network 900 and 1800 in Semarang city, which has area of 373.67 km2 and consists of 16 districts and 177 villages, so it can serve customers until 2014. From re-planning simulation for GSM 900 and 1800 radio network outdoor site coverage system in Semarang,can be known the needed number of sites to serve the customers until the year 2014 with a teledensity of 30%, i.e 91 sites with 250 Global System for Mobile Communication (GSM) sectoral cells and 230 Digital Cellular System (DCS) sectoral cells with the highest traffic for the micro cells occurred at sector 3, Sendangguwo village, District Tembalang that is equal to 132.36 Erlang, while the highest traffic for the macro cells occurred in Sector 3 Bamban Kerep village, District Ngaliyan which amounted to 66,24 E. Keywords: Re-planning, site, GSM, coverage, Semarang City

Pervasive RF energy harvesting system (GSM 900 and GSM 1800)

Abstract: RF energy harvesting holds a promising future for generating a small amount of energy to potentially power on low power devices like wireless sensor network. Due to path loss and restriction on transmit power; the RF power available to the input of the RF energy harvesting system is relative low. In this work, we show how wireless power transfer can occur more efficiently by the design of a high Q coil antenna. The receiving antenna and RF-DC converter are being analyzed and discussed. Finally, a prototype is fabricated and it shows capability to harvest a voltage in the range of 2V stored in the super capacitor from the air without a prominent source nearby. So, is RF energy harvesting ever going to become a practical reality? The answer is a cautious yes.