Showing papers on "GSM frequency bands published in 2012"
01 Nov 2012
TL;DR: The primary user information is based on the Multimedia Communication (MCMC) data to detect the spectrum hole from the information of the primary user.
Abstract: Matched filter detection is one of the spectrum sensing techniques in cognitive radio system that facilitate to detect vacancies in spectrum frequency Matched filter is the optimal way to detect the spectrum hole from the information of the primary user In this paper the primary user information is based on the Multimedia Communication (MCMC) data Spectrum sensing is carrying out on the GSM 900 bands to identified the potential spectral opportunities for cognitive radio applications
11 citations
01 Dec 2012
TL;DR: In this paper, the authors proposed an eight-band LTE/WWAN antenna for mobile phone application, which has advantages of dual wide bands and small dimension, is composed of a meandered coupled-fed monopole that excites a fundamental mode at 718 MHz and a meanderered directed-fed magneto that excite the other fundamental modes at 918 MHz.
Abstract: This paper proposes an eight-band LTE/WWAN antenna for mobile phone application. The proposed antenna, which has advantages of dual wide bands and small dimension, is composed of a meandered coupled-fed monopole that excites a fundamental mode at 718 MHz and a meandered directed-fed monopole that excites the other fundamental mode at 918 MHz. By adjusting the parameters of the proposed design, the two resonant modes gather to form a low operation band (690–975 MHz) based on the 6-dB return loss for LTE 700, GSM 850, and GSM 900 applications. The higher modes of the two resonant modes produce a high operation band (1600–2200 and 2268–3000 MHz) for GSM 1800, GSM 1900, UMTS 2100, LTE 2300, and LTE 2500 applications. The overall dimensions of the proposed antenna are 120×65×0.8 mm3 that consists of an antenna portion of 10×65 mm2 and a ground plane of 110×65 mm2. The antenna's operation bands and size are suitable to apply in smart phone.
11 citations
TL;DR: In this paper, the authors presented and analyzed EMFs produced by mobile communication antennas in a residential area and measured the electric strength, magnetic strength and EMF power density of the antennas.
Abstract: As the network of cellular mobile phones has recently expanded and in particular after the digital GSM 900/1800/2100 systems have been introduced, the potential effect on human health of electromagnetic radiation from the base stations of these systems has become of great concern to European countries. There have been requests made in some countries for areas free from mobile phones in which installation of base stations would not be permitted and for considerable reduction of the maximum authorised exposure or other restrictions. The European Commission's Recommendation adopted on 12 July 1999 requires that the maximum field strength for electromagnetic radiation (0–300 GHz) is established and that information about population's exposure to EMF and the measures taken to reduce it is provided. The article presents and analyses EMFs produced by mobile communication antennas in a residential area. Measurements of the electric strength, magnetic strength and EMF power density were performed and comp...
10 citations
TL;DR: In this paper, a 377 Ω E-shaped patch antenna with partial ground plane is presented and discussed, and two parallel slots are introduced into the conventional patch antenna, and it was investigated by the currents through the patch to enhance its bandwidth.
Abstract: The design of a 377 Ω E-shaped patch antenna with partial ground plane is presented and discussed in this article. Two parallel slots are introduced into the conventional patch antenna, and it was investigated by the currents through the patch to enhance its bandwidth. The antenna is designed, fabricated, and measured for downlink frequency band of GSM 900, which shows an impedance bandwidth of 29.03% (277 MHz) at 954 MHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:569–573, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26607
9 citations
25 Oct 2012
TL;DR: In this article, a simple dual-band GSM 900/1800 microstrip patch antenna with single feeding is presented, where the dual resonance was obtained by cutting a narrow slot in the patch near the radiating edge which influenced the patch modal currents.
Abstract: Design of a simple dual-band GSM 900/1800 microstrip patch antenna with single feeding is presented The dual resonance was obtained by cutting a narrow slot in the patch near the radiating edge which influenced the patch modal currents Similar radiation characteristics in both bands were observed The calculated results were confirmed by measurements on the prototype
5 citations
TL;DR: In this article, AWAS electromagnetic code and conventional prediction methods have been employed to explain the observed results of ten base stations mainly in the near fleld zones of GSM 900MHz band situated in the urban and suburban regions around Delhi in India.
Abstract: Recent trends in propagation modeling indicate the study of mobile radio propagation modeling with the help of electromagnetic formulations which traditionally has been explained with empirical methods. These empirical methods were preferred by the cellular operators in their radio planning tools due to their ease of implementation and less time consumption. In the present study, AWAS electromagnetic code and conventional prediction methods have been employed to explain the observed results of ten base stations mainly in the near fleld zones of GSM 900MHz band situated in the urban and suburban regions around Delhi in India. The suitability of the above models in terms of prediction errors and standard deviations are presented. Path loss exponents deduced from the observed data have been explained by Sommerfeld's formulations.
4 citations
25 Oct 2012
TL;DR: The study demonstrates that an appropriately programmed standard cellular handset can provide a simple, inexpensive solution for accurate room-level indoor localization.
Abstract: Accurately localizing users in indoor environments remains an important and challenging task. The article presents new results on room-level indoor localization, using cellular Received Signal Strength fingerprints collected with a standard cellular handset programmed to perform fast scans of the 900 and 1800 Megahertz GSM bands as a user explores an indoor environment at a normal walking pace. Support Vector Machines are used to deal with the high dimensionality of the fingerprints. The study demonstrates that an appropriately programmed standard cellular handset can provide a simple, inexpensive solution for accurate room-level indoor localization.
4 citations
Patent•
07 Mar 2012
TL;DR: In this paper, an automatic frequency-selecting GSM digital optical fiber repeater is realized very simply and effectively, so that the difficulty and the complexity in changing the frequency points of the repeater are reduced, and an important reference and realistic significance for solving the technical problems in the similar design.
Abstract: The invention relates to an automatic frequency-selecting GSM (Global System for Mobile Communication) digital optical fiber repeater and a realizing method thereof. An automatic frequency-selecting DDC (Digital Digital Control) channel is additionally arranged in a downlink of a digital frequency-selecting repeater, all GSM frequency points are circularly traversed through correcting a working frequency point of the automatic frequency-selecting DDC channel, then the power of each frequency point is counted by a frequency point power counting module, an effective frequency point is selected according to the power of each frequency point by using a certain algorithm, and the working frequency point of the frequency-selecting repeater is configured according to the selected effective frequency point so that the repeater normally works. The invention has the beneficial effects that: the effective frequency point is selected by adopting a sweep frequency technology, a new frequency point can be rapidly added under the condition that the new frequency point appears, effective frequency point Delete Time is set in the original frequency point in use according to actual conditions so as to decide that the current frequency point is deleted within what duration when no new frequency point appears. The automatic frequency-selecting GSM digital optical fiber repeater is realized very simply and effectively, so that the difficulty and the complexity in changing the frequency points of the frequency-selecting repeater are reduced, and an important reference and realistic significance is provided for solving the technical problems in the similar design.
4 citations
Patent•
19 Sep 2012
TL;DR: In this paper, a global system for mobile communication (GSM) frequency deviation estimation method is proposed, which comprises the following steps that: all GSM carrier frequency is searched; the carrier frequency which contains a frequency correction channel (FCCH) is locked; and frequency deviation is estimated according to the extracted FCCH signal.
Abstract: The invention discloses a global system for mobile communication (GSM) frequency deviation estimation method which comprises the following steps that: all GSM carrier frequency is searched; the carrier frequency which contains a frequency correction channel (FCCH) is locked and an FCCH signal is extracted; and frequency deviation is estimated according to the extracted FCCH signal According to the method, the real-time performance is strong, the computing precision is high, the hardware is easy to realize, the frequency deviation value of a GSM signal can be accurately estimated, particularly the Doppler frequency deviation value of the GSM signal under a high-speed environment can be estimated in real time The invention also discloses a GSM frequency deviation estimation system which comprises a carrier frequency searching module, an FCCH signal extraction module and a frequency deviation estimation module According to the invention, the signal quality in a carriage can be improved on a vehicle-mounted repeater, so that the cutting off rate can be effectively improved, and the GSM signal is not off line and cannot be normally called, switched and the like
3 citations
Journal Article•
TL;DR: In this paper, the occupational exposure due to RF radiation leaks inside the base station cabin, when working on the BTS Radios and TX cables and during active radio communication was measured.
Abstract: The occupational exposure due to RF radiation leaks inside the base station cabin, when working on the Base station Transceiver (BTS) Radios and TX cables and during active radio communication was measured. A total of number 30 base stations Cabins were studied in the eastern part of Nigeria, using a Broad band TES-90 Electrosmog meter. The maximum instantaneous electric field strength obtained from GSM 1800 radio was 3.72 V/m, 16.56 V/m for GSM 900 radio and 11.29 V/m for the Tx cables. The maximum instantaneous indoor and out power density were 35.47 mW/m 2 and 6.64 mW/m 2 respectively. Also, the average values of the obtained electric field strength from all the cabins are 1.18 ± 1.07 V/m from GSM 1800 radio, 2.33 ± 3.82 V/m from GSM 900 radio and 1.77 ± 2.20 V/m from the Tx cables. The result of this study shows that the values were less than ICNIRP limits for occupational exposure.
3 citations
Patent•
12 Sep 2012
TL;DR: In this paper, the authors presented a digital processing system and digital processing method applied to a repeater of a global system for mobile communication (GSM) frequency hopping network, which consisted of the following steps that: a baseband processing module converts a frequency hopping signal of a source base station into a constant frequency signal, arranges the constant frequency to each idle timeslot of a broadcast control channel carrier frequency frame structure, and forwards the constant signal to a covered user area by utilizing broadcast control channels carrier frequency; or the base-band processing modules rearranges the data of each
Abstract: The invention discloses a digital processing system and a digital processing method applied to a repeater of a global system for mobile communication (GSM) frequency hopping network. The method comprises the following steps that: a base-band processing module converts a frequency hopping signal of a source base station into a constant frequency signal, arranges the constant frequency to each idle timeslot of a broadcast control channel carrier frequency frame structure, and forwards the constant frequency signal to a covered user area by utilizing broadcast control channel carrier frequency; or the base-band processing module rearranges the data of each timeslot of the broadcast control channel carrier frequency frame structure, converts the data into the constant frequency signal, converts the constant frequency signal into the frequency hopping signal, and forwards the frequency hopping signal to the source base station. According to the digital processing system and the digital processing method applied to the repeater of the GSM frequency hopping network, a normal service of a user is ensured, and the requirement of a multi-carrier frequency signal of the repeater for the high linearity of power amplifiers of the repeater is lowered; and when the broadcast control channel carrier frequency is used for transmitting information, only a slave power amplifier of the repeater is required to be started, so that equipment power consumption is reduced, and the energy-saving requirements of the repeater are met.
Patent•
16 May 2012
TL;DR: In this paper, a global system for mobile communications for railway (GSM-R) indoor coverage device for a railway passenger dedicated line and belongs to application of a GSM network in the railway passenger designated line, in which deep coverage of an indoor key region is realized.
Abstract: The invention discloses a global system for mobile communications for railway (GSM-R) indoor coverage device for a railway passenger dedicated line and belongs to application of a GSM network in the railway passenger dedicated line, in which deep coverage of an indoor key region is realized. Indoor coverage mainly supplies a voice service and a general packet radio service (GPRS) data service; covered regions comprise a dispatching office, a communication station, a signal building, a railway public security station, station houses and underground regions; and a system design obeys the following rules that: a signal source is required to be selected rationally according to a wireless signal environment and a capacity requirement of the covered region by combining a service development tendency; on the premise of meeting the requirement on the indoor coverage capacity, base stations near the covered region are connected as much as possible instead of arranging new base stations; according to the characteristic of the covered region, an antenna feedback mode is selected rationally, and a rule of the fewest antennas is required to be obeyed under the condition of wireless coverage; indoor coverage signals are strictly controlled within a limited range, so interference to a GSM-R network can be avoided; and the indoor coverage device is compatible with frequency ranges of GSM 900 MHz/1,800 MHz and code division multiple access (CDMA) 800 MHz, so a combined circuit is retained.
01 Jan 2012
TL;DR: Over the years, the GSM has won the minds and souls billions; it is in use in over 200 countries worldwide and accounts for over 70% of the world's digital market.
Abstract: The Global System for Mobile Communications (GSM) signal was first powered on in Finland in radiolinja's network at 900 MHz in 1991. There were plans since the 1982 by the Conference of European Post and Telecommunication Administrators (CEPT) to develop a pan-European compatible cellular system. Although the CEPT created the Group Special Mobile (GSM) standard, the development was continued by the European Telecommunications and Standards Institute (ETSI) which published the first phase of the GSM standards in 1989 (Gold, 2011). Over the years, the GSM has won the minds and souls billions; it is in use in over 200 countries worldwide and accounts for over 70% of the world's digital market (Gold, 2011). The architecture of the GSM is hierarchic simple and consists of four main components namely;
26 Jul 2012
TL;DR: A Microstrip triple-band band pass filter for GSM 900, GPS - L1 band and 2.4 GHz -WLAN applications is designed and simulated using Agilent® ADS software to achieve good out of band rejection.
Abstract: A Microstrip triple-band band pass filter for GSM 900, GPS - L1 band and 2.4 GHz -WLAN applications is designed and simulated using Agilent® ADS software. Three transmission zeros are inserted at frequencies of 1.31 GHz, 1.96 GHz and 2.89 GHz, to achieve good out of band rejection. Insertion loss of 3.88 dB, 3.78 dB and 4.8 dB at central frequencies of 925 MHz, 1.575 GHz and 2.4475 GHz are observed for the designed filter, measured after the fabrication.
Patent•
31 Oct 2012
TL;DR: In this article, a GSM (Global System for Mobile Communication)-LTE/LTE-A (Long Term Evolution/ Long Term Evolution-Advanced) common-mode method and system was proposed.
Abstract: The invention discloses a GSM (Global System for Mobile Communication)-LTE/LTE-A (Long Term Evolution/ Long Term Evolution-Advanced) common-mode method and system The method comprises the steps of: embedding a GSM bandwidth serving as a subband into an LTE/LTE-A system bandwidth for realizing common carrier frequency of a GSM and an LTE/LTE-A system, wherein when the GSM bandwidth serving as the subband is embedded into the LTE/LTE-A system bandwidth, the embedded positions keep away from a static pilot frequency and a static physical channel in the LTE/LTE-A system bandwidth; after embedding the GSM bandwidth serving as the subband into the LTE/LTE-A system bandwidth, when an RRC (Radio Resource Control) of the LTE/LTE-A system carries out resource planning, keeping away from the embedded GSM frequency band; and when an MAC (Media Access Control) of the LTE/LTE-A system carries out resource scheduling, keeping away from the GSM frequency band used by a local cell According to the invention, the defects of poor frequency spectrum utilization rate and low frequency spectrum efficiency of the GSM are made up through the LTE/LTE-A system, and the frequency spectrum frequency is greatly increased
01 Sep 2012
Patent•
03 Oct 2012
TL;DR: In this paper, the authors proposed a method for obtaining frequency hopping synchronization by using baseband decoding, which comprises the following steps: first, the radio-frequency signals of a GSM base station are obtained by a coupler, a base-band decoding module digitally decodes and demodulates the radio frequency signals of the GSM BS, and finally, the base band decoding module transmits the information to a micro control unit (MCU), and the MCU synchronously maintains frame heads and frequency points through a local clock.
Abstract: The invention relates to a method for obtaining frequency hopping synchronization by using baseband decoding, which comprises the following steps: firstly, radio-frequency signals of a GSM base station are obtained by a coupler, a baseband decoding module digitally decodes and demodulates the radio-frequency signals of the GSM base station; secondly, the baseband decoding module transmits the information to a micro control unit (MCU); and thirdly, the MCU synchronously maintains frame heads and frequency points through a local clock, thereby obtaining the frequency hopping synchronization synchronizing with the radio-frequency signals of the GSM base station. The invention can effectively improve the wireless network quality, reduces the interference of relay signals to the base station and the interference among the frequency points under GSM frequency hopping, improves the use reliability, has stronger practicability, is suitable for a GSM mobile network optimizing device and can greatly improve the quality of a GSM wireless network.
01 Oct 2012
TL;DR: In this paper, the specific absorption rate (SAR) in 10 g of tissue mass was determined by means of electromagnetic field simulation using CST software for GSM 900 and GSM 1800 frequencies.
Abstract: In the present paper the specific absorption rate (SAR) in 10 g of tissue mass was determined by means of electromagnetic field simulation using CST software for GSM 900 and GSM 1800 frequencies. In this scope far field exposure of a human head model, SAM phantom (specific anthropomorphic Mannequin) was analyzed and the results have been compared for different far field sources.
Patent•
11 Jul 2012
TL;DR: In this article, an automatic frequency selecting GSM (Global System for Mobile Communications) digital optical fiber repeater has been proposed, which is very simple and effective to implement; the difficulty and the complexity of changing the frequency point of a frequency selecting repeater system are greatly reduced.
Abstract: The utility model relates to an automatic frequency selecting GSM (Global System for Mobile Communications) digital optical fiber repeater. An automatic frequency selecting DDC (Direct Digital Control) channel for circularly traversing all GSM frequency points by modifying a working frequency point of the automatic frequency selecting DDC channel is added into an FPGA (Field Programmable Gate Array) of a down link of a digital frequency selecting repeater; a frequency point power statistics module is added into the FPGA and is used for carrying out statistics on the power of each frequency point; the output end of a forming filter is connected with an effective frequency point judging module through the frequency point power statistics module; and the effective frequency point judging module is used for selecting effective frequency points according to the size of the power of each frequency point and configuring the working frequency point of the frequency selecting repeater according to the selected effective frequency points. The automatic frequency selecting GSM digital optical fiber repeater has the beneficial effects that the automatic frequency selecting GSM digital optical fiber repeater is very simple and effective to implement; the difficulty and the complexity of changing the frequency point of a frequency selecting repeater system are greatly reduced; and the automatic frequency selecting GSM digital optical fiber repeater has great reference and practical significances for solving the technical difficult problems of the like design.
01 Oct 2012
TL;DR: In this article, the influence of user demands and expected rate of broadband adoption (Broadband intensity) to UMTS900 greenfield overall planning is considered Load factor and calculation method for a planned service mix has been proposed even simplified, dedicated to the first phase of planning.
Abstract: Implementing UMTS system in the GSM frequency band has gained a lot of attention in Europe in the last few years There are several reasons for this Those include better radio propagation in the lower frequency band, resulting in much lower price per bit for operators In remote, sparsely populated areas, operators face cost-efficiency difficulties in providing UMTS at 2GHz range However, by implementing UMTS at 900 MHz range, significant site number reduction can be achieved when comparing to 2GHz band for the same coverage Following trends, operators in B&H have chosen to introduce UMTS900 technology in their mobile networks as well, providing global UMTS coverage very efficient When it comes to UMTS network planning, coverage and capacity must be planned simultaneously, because traffic distribution, used services, and capacity requirements does have an impact to cell sizes In this paper, influence of user demands and expected rate of broadband adoption (Broadband intensity) to UMTS900 greenfield overall planning is considered Load factor and calculation method for a planned service mix has been proposed Even simplified, dedicated to the first phase of planning, there is a need for method of planned broadband intensity in advance, integrated into the load factor equation Broadband intensity parameter a has been introduced, and effect of changing of this parameter to actual network planning is presented
01 Oct 2012
TL;DR: In this article, an automated electric field measurement system is presented, associated with a statistical analysis of the results obtained from a survey in the GSM 900, GSM 1800 and 3G downlink frequency bandwidths for different time frames.
Abstract: Measuring the electric field due to wireless communication systems is an important part for determining the electromagnetic pollution of the environment and consequently human exposure to these fields. Many difficulties need to be considered when performing these tests. An automated electric field measurement system is presented in this paper, associated with a statistical analysis of the results obtained from a survey in the GSM 900, GSM 1800 and 3G downlink frequency bandwidths for different time frames. Instantaneous measurements were taken at 1 second intervals and the minimum, maximum, average, standard deviation and the cumulative density were calculated.
Patent•
07 Aug 2012
TL;DR: In this paper, a method for calibrating the transmission GSM frequency band power of a mobile terminal is presented, including a calibration system setting a reference channel and reference radio frequency signal line loss of a corresponding working frequency band.
Abstract: Disclosed is a method for calibrating the transmission GSM frequency band power of a mobile terminal, including: a calibration system setting a reference channel and reference radio frequency signal line loss of a corresponding working frequency band, the calibration system setting a radio frequency parameter of a mobile terminal, the mobile terminal successively outputting a series of signals with different powers, and a base station emulator of the calibration system reading and storing the corresponding parameters of various power signals; setting a radio frequency signal line loss corresponding to the next channel of the corresponding working frequency band; and the calibration system setting the radio frequency parameter of the mobile terminal, the mobile terminal successively outputting a series of signals with different powers, and the base station emulator reading and storing the corresponding parameters of various power signals. The present invention can set different target powers for different channels. By way of setting corresponding radio frequency signal line losses, the calibration accuracy is improved, which is convenient for debugging mobile phone antennas, and a significant progress over the prior art.
01 Jan 2012
TL;DR: In this article, the authors compared the various exposure systems and parameters involved to study the effect of 900 MHz frequency on human body, and found that the effects of high frequency exposure to human body were not as significant as those of low frequency exposure.
Abstract: The concern to human health due to excessive exposure to continuous low RF frequency range of 900 MHz arising out of increased usage of mobile phones is of great importance. This paper compares the various exposure systems and parameters involved to study the effect of 900 MHz frequency on human body.
01 Jan 2012
TL;DR: A new intelligent algorithm of analysis and optimization on co-channel and adjacent channel interference based on the cells basic configuration information is proposed, which demonstrates advantages in intelligence, accuracy, timeliness, and visualization.
Abstract: Most current methods of GSM frequency planning evaluate interference and assign frequencies based on the measurement reports. The same or adjacent frequencies are assigned to cells close to each other which cause co-channel and adjacent channel interference, and reduce the network performance. The traditional method to check and allocate the new frequencies is by man power which costs much time and the accuracy is not satisfied. This paper proposes a new intelligent algorithm of analysis and optimization on co-channel and adjacent channel interference based on the cells basic configuration information. The algorithm defines an interference evaluation model analyzing various factors such as the base station layer, the azimuth ward relationship, the cell neighborhood relationship, etc. The interference performance of each frequency can be evaluated and the problem frequencies can be optimized. This method is verified by a large number of actual datasets from an in-service GSM network. Contrast with the traditional method, this method demonstrates advantages in intelligence, accuracy, timeliness, and visualization.