Field Strength Meter Research Articles

Measurement of digital video broadcasting-second generation terestrial (DVB-T2) signal in Kuala Lumpur, Malaysia

<span style="font-size: 9pt; font-family: 'Times New Roman', serif;">DVB-T2 (Digital Video Broadcasting – Second Generation Terrestrial) is one of the latest technical standards being developed by the DVB Project for DTT (Digital Terrestrial Television). It is also known as digital broadcasting trough terrestrial system since 2006 and is an extension of the DVB-T system as a second generation program to improve efficiency of the total system. It is important to perform a research on the performance of DVB-T2 because Malaysia has launched the free-to-air digital TV project since 2016 hence there is a need to know how well the signal is being received by viewers. This research focuses on a DVB-T2 transmission process which involve the transmission from Menara Kuala Lumpur transmitter to receivers located at 100 different locations. The performance of DVB-T2 can be determined by measuring the field strength, MER (Module Error Ratio) and BERaLDPC (Bit Error Rate after Low Density Parity Check decoder), and then a comparison between DVB-T and DVB-T2 systems can be made. Equipments involved in the measurement are indoor antenna, distribution amplifier, waveform monitor, field strength meter, DVB-T2 decoder and TV set as the receiver. Results are recorded in Microsoft Excel and analyzed using MATLAB software. The result of the measurement shows92% of the test points had higher reading than the baseline value which means better reception of digital TV signal is delivered to the location.Comparison between DVB-T and DVB-T2 performance shows that field strength of the DVB-T2 system is slightly higher by 1.5 % – 3.8 % from DVB-T</span><p class="MsoNormal"><span style="font-size: 16.0pt; line-height: 107%; mso-bidi-font-style: italic;">Measurement of digital video broadcasting-second generation terestrial (DVB-T2) signal in Kuala Lumpur, Malaysia</span></p>

Uncertainty in Field-Level Measurements of LTE Signals Associated With User Load

Recent modulation schemes in mobile communications, as Long Term Evolution (LTE), give rise to the question of how to properly assess the exposure to the electromagnetic fields generated by base station signals . This letter examines the changes in the field strength associated with the user load variations in the LTE signals. First, we have generated a set of signals, with the same configuration parameters, modifying only the percentage of user load and simulating how it alters the field level. Then, a setup for measurements is defined, and two electric field probes are exposed to the previous analyzed signals in a controlled environment. Field strength meter readings are recorded as in a real case of exposure evaluation. Uncertainties concerning probes performance and environmental conditions are also calculated to have an overall budget. Due to the user load changes, field-level variations up to 11 dB have been found. The measurement uncertainty of the exposure level may be dramatically increased by these field fluctuations.

Comparison of Electromagnetic Wave Intensity from Different Type of Communication Towers in Kurdistan Region

With increasing of the usage of the mobile communication devices and internet network information the electromagnetic pollution produced. the entry of private telecommunications companies in Iraq has been started since 2003, These companies began to build up cellular towers to accomplish the telecommunication works, but they ignore the safety conditions imposed for the health and environment as a result a health risk for life beings and environment. The aim of this work is to determine the safe and unsafe ranges. Discuss damage caused by radiation emitted from (Asia cell) and (Korek telecom) base stations in Erbil and Sulimania Cities, and compare it with international standard exposure limit. Practical measurements of power density around base stations has been accomplished by using Electromagnetic Field strength meter

Assessment and Modeling of GSM Signal Propagation in Uyo, Nigeria

High quality of service is a paramount concern in wireless networks. One of the strategies in achieving optimal performance is to use wireless empirical models to predict wireless link quality factors such as path loss and the received power in any given transmission domain with irregular terrain. The primary goal of this study is to develop a radio wave propagation model for Uyo metropolis. An assessment was carried out in three major roads within the city of Uyo in Akwa Ibom State, to determine the quality of GSM signal reception by measuring the signal field strength, magnetic field strength, and power density of the base transceiver stations. The measurements were carried out using radio frequency electromagnetic field strength meter over a distance of 2000 meters from the base stations. The results of the measurements were analysed and a path loss model was developed for Uyo using linear regression model. Three empirical models: Okumura-Hata model, COST-Hata model, and Egli model were also applied in predicting the path loss in Uyo and the results obtained were compared with the developed model for Uyo metropolis. The comparison showed that Route D model had a better comparison factor with the developed model while the Okumura-Hata and COST-Hata were almost the same with more loss as the distance increased. In all the measurements, the standard deviation was between 3.31 dB and 3.36 dB.

Assessment and Modeling of GSM Signal Propagation in Uyo, Nigeria

High quality of service is a paramount concern in wireless networks. One of the strategies in achieving optimal performance is to use wireless empirical models to predict wireless link quality factors such as path loss and the received power in any given transmission domain with irregular terrain. The primary goal of this study is to develop a radio wave propagation model for Uyo metropolis. An assessment was carried out in three major roads within the city of Uyo in Akwa Ibom State, to determine the quality of GSM signal reception by measuring the signal field strength, magnetic field strength, and power density of the base transceiver stations. The measurements were carried out using radio frequency electromagnetic field strength meter over a distance of 2000 meters from the base stations. The results of the measurements were analysed and a path loss model was developed for Uyo using linear regression model. Three empirical models: Okumura-Hata model, COST-Hata model, and Egli model were also applied in predicting the path loss in Uyo and the results obtained were compared with the developed model for Uyo metropolis. The comparison showed that Route D model had a better comparison factor with the developed model while the Okumura-Hata and COST-Hata were almost the same with more loss as the distance increased. In all the measurements, the standard deviation was between 3.31 dB and 3.36 dB.

Electromagnetic Field Radiation Exposure Assessment from Mobile Phones Based on Call-Related Factors

For many years, there have been concerns about possible human health risks connected to the usage of mobile phones especially at close proximity. This is primarily due to the exposure to electromagnetic field (EMF) radiations that emanate from them. These concerns have in turn provoked a large bulk of research studies. However, the conflicting reports of previous research works on the effect of the exposure to EMF sources lead researchers to continue studying the issue. In this work, by means of the exposure evaluation technique, measurements of EMF radiations, in terms of power density, are conducted on different models of mobile phones in an indoor environment via the call-related factors: between the dial and reception of a call from different models of mobile phones, for a period of six months. The investigated brands of mobile phones were all placed to face the field strength meter sensor in active call modes at 0.05m measurement interval when taking reading on the tri-axis planes. The results obtained revealed that the EMF radiation intensity, in terms of measured power density from the mobile phone, varies and depends on the mobile phone model brand. It ranges from 1.25 to 800.5 mW/m2 with the highest from ITEL phone (Model-TI65800) with MTN Network along the Z-plane and the lowest from NOKIA phone (Model-105) with MTN Network along the Y-plane. The highest radiation intensity was recorded for calls made during the dial (before picking) from all the selected mobile phone models. In particular, from the results, it was observed that the amount of EMF radiations decreased about 20 to 30 % if the mobile phone handset is moved away from the EMF meter from 1cm to 5cm. Accordingly, for EMF exposure safety, it is recommended that the mobile phone is placed 5–10 cm away from the body during conversation.

GHz帯域電界強度計の教材化 : 「光るアンテナ」による受信強度測定と八木アンテナの指向性の確認(北海道支部特集)

GHz帯域電界強度計の教材化 : 「光るアンテナ」による受信強度測定と八木アンテナの指向性の確認(北海道支部特集)

LONG-TERM ELECTROMAGNETIC FIELD MEASUREMENT AND ASSESSMENT FOR A SHOPPING MALL.

As a result of the dense deployment of wireless devices and base stations, measuring and evaluating the electromagnetic (EM) exposure levels they emit have become important to human health especially if they exceed the limits defined in the standards. Base stations, Wi-Fi equipment and other electronic devices are used heavily, especially in densely crowded places like shopping centers. In this study, electric field strength (E) measurements were conducted at one of the largest shopping malls in Turkey. Broadband E measurements were performed using PMM 8053 EM field strength meter for 24 h a day for the duration of one week while frequency selective measurements were carried out with SRM-3006 EM field strength meter. It is concluded from the measurements that the mean measured total E in the band between 100 kHz and 3 GHz is 0.59 V/m while the maximum E is 7.88 V/m, which are both below the limit determined by International Commission on Non-Ionizing Radiation Protection. Evolutions show that E can increase by up to 55% during the daytime. Analyses demonstrate that 71.3% of total E is caused by UMTS2100, 16.3% is produced by GSM900, 6.2% by LTE, 3.5% by Wi-Fi, and 2.7% is generated by devices that use the remaining frequency bands. Based on the detailed statistical analysis of long-term E measurement results, it can be concluded that the measured E levels are not in normal distribution and that they are statistically different with respect to days. Furthermore, distribution of E can be best modeled with the non-parametric approach.

Prediction of Path loss Estimate for a Frequency Modulation (FM) Station Using Basic Transmission Loss Model

This paper presents the path loss model that seeks to predict the signal strength degradation of Radio Nigeria, FM station, Makurdi which is normally a major component in the analysis and design of link budget of a telecommunication system. For the purpose of this work, Benue state was divided into four (4) routes for ease of data gathering, namely northern, southern, eastern and western parts and a Potomac FIM-41 field strength meter was used to measure the signal strength of the FM signal at selected locations. The values obtained are compared with those computed from Basic Transmission Loss Model for consistency. The result shows that values obtained from the model are slightly higher than the measured and it returned ninety-five percent (95%) confidence interval for the two samples using degree of freedom of 22. A null hypothesis was applied and the measure of the level of significant difference between the model and measured values is 10.3%. The results present no significant difference between the model and measured data. It can therefore be concluded that the model is valid and can be used to estimate path losses of FM signals in Benue State of Nigeria.

TD-SCDMA Smart Antenna Signal Intensity Measurement System

With the rapid development of China's TD-SCDMA system, how to qualitative and quantitative to judge intelligent antenna electromagnetic radiation pollution is a problem to be solved. Due to the special working principle of smart antenna, the second generation communication system spectrometer and field intensity meter measurement method is a complicated and difficult to operate. This paper introduces a design suitable for TD smart antenna measurement system: this system can realize in single user or multiple users at the same time and the TD base station set up calls link of multi-point synchronous signal intensity measurement. The measurement results of our system are very close to the measurement results of spectrometer field intensitys and can reasonable reflect TD stations around the extent of the electromagnetic radiation. This method of our system is easy, cheap and maneuverable

Traceable electric and magnetic field calibrations of radiation monitors for amateur radio inside a parallel plate transmission line up to 30 MHz

Abstract. In many countries the electromagnetic field strength in the proximity of licensed amateur radio stations is limited to ensure public safety. If the station antenna(s) and/or the environmental situation are complex, only measurement results are acceptable as proof, and proper calibration of the field strength meters ("radiation monitors") is mandatory. A system and a procedure are described here, enabling calibration of such "radiation monitors" at a high quality level and traceable to the SI units, but with low-budget amateur equipment.

In vitro tests of electromagnetic interference of electromagnetic navigational bronchoscopy to implantable cardioverter defibrillators

To characterize the electromagnetic field emitted by the electromagnetic navigational bronchoscopy (ENB) superDimension(®) Bronchus system (SDBS) and to determine whether current implantable cardioverter defibrillator (ICD) systems are suitable for use in conjunction with SDBS. The electromagnetic emission of the SDBS location board were measured using a field strength meter connected to a low-frequency (5 Hz-100 kHz) electric and magnetic field analyser; the static magnetic field was measured using a three-axis Tesla meter. A human torso simulator was used in the in vitro experiment: a polyethylene plastic box (61 cm length × 43 cm depth × 16.5 cm height) was filled with a semisolid gel and a 0.45% saline solution to provide electric conductance similar to tissue. The ICDs were immersed 1 cm into the gel and connected with a dual-coil integrated bipolar pacing/sensing/shock lead. Tip and right ventricular coil of the lead were connected to an arrhythmia simulator using low-impedance cables. The system transmits electromagnetic waves of 2.5, 3.0, and 3.5 kHz frequency. The maximum magnetic fields measured were B = 53 and 12 µT at location board plane and at ICD plane, respectively. Corresponding figures for the electric field were E = 16.6 and 4.4 V/m. None of the tested ICDs recorded any noise signal during the period in which the location board was switched-on. Stored electrogram analysis confirmed the correct detection of simulated tachyarrhythmia and therapy delivery by every tested ICD. The results of this study demonstrated that tested ICDs are compatible with ENB performed with SDBS. They also suggest that these results may be extended to all ICDs manufactured in compliance with current EN regulations.

Neuro-Fuzzy Based Modeling of Electrostatic Fields for Harmattan Season in Zaria

This paper presents a Neuro-Fuzzy based modeling of electrostatic fields for harmattan season in Zaria, Nigeria based on online based data capturing mechanism, which involved the use of a data acquisition system interfaced with a digital electrostatic field strength meter (model 257D) and a computer system. The acquired electric field data were captured by the computer using the Microsoft Office Excel Program for twenty-four months (February 2007 – February 2009). The focus of the analysis is determining the effect of environmental factors such as temperature, pressure and relative humidity on the static electric field during the harmattan season. The plots of the electrostatic field against the variation of the environmental factors were used as the qualitative analytical tools and yielded a non-linear relationship. The data was analyzed using Neuro-Fuzzy technique, which is a hybrid intelligent system combining the benefits of computational techniques of Fuzzy Logic and Artificial Neural Networks. The result of the analyses yielded good neural statistical values of Root Mean Square (RMS) of 0.32, Average Absolute Error of 0.18, and Pearson R value of 0.96 for the harmattan scenario, which are reflections of a good model. The result was further buttressed by the 3D plot of the Neuro-Fuzzy based modeling of the experimental parameters. With the insignificant values of the RMS and Average Absolute value, the empirical model gave a fairly good prediction which could be relied upon to predict the electrostatic fields during harmattan in Zaria, Nigeria.

Final report on supplementary comparison EUROMET.EM.RF-S25 (EURAMET project 819): Comparison of electrical field strength measurements above 1 GHz

This report presents the results of an international comparison of electric field strength in the frequency range (1 to 2.5) GHz which has been carried out among ten laboratories. As the travelling standard a measuring system with a small linearly polarized E-field sensor was used. The parameter compared was the field strength appropriate for the circulated field strength meter indication of 20 V m−1. Basically, four types of calculable field strength realizations were used (rectangular waveguide, small TEM cell, reference transmitting antenna, reference receiving antenna). Some of the reported values obtained in anechoic chambers by using reference transmitting antennas ('standard field method') and in TEM cells are inconsistent with the claimed uncertainties.Main text.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Control of electrostatic charge for powder by using feedback control-type ionizer system

As a method to prevent or mitigate cone discharges in a specific section such as a large silo, we have developed a new feedback control-type ionizer system. The feedback control-type system is composed mainly of an ionizer, an electrostatic field strength meter, and computer control equipment. In this study, we evaluated experimentally the practical version of the feedback control-type ionizer system through several tests in a pneumatic powder transport facility. The specific charges of the falling pellets in the silo were also measured for 10 s using a Faraday cage. Polypropylene (PP) pellets with a mean particle size of 3 mm were used in this experiment. The results of the experiment revealed that the feedback control-type ionizer system had the following characteristics: (1) it is possible to control the performance of the ionizer with a supply current; (2) the electrostatic field strength in the loading pipe from the charged powder is reduced and maintained at near zero by using the feedback control-type system; and (3) the performance of the feedback control-type system is superior to that of others, such as the conventional AC- or DC-type ionizers.

Comparative Analysis of Electric Field Measurement in Zaria

This paper presents the comparative analysis of the measurement of static electric field within and outside the test location in Zaria, Nigeria, based on the measurement carried out using a data acquisition system, interfaced with a digital electrostatic field strength meter (model 257D). The acquired electric field data are captured by a computer using the Microsoft Office Excel Program. The focus of the analysis is determining the effect of environmental factors such as temperature, pressure and relative humidity on the static electric field during the harmattan (March) and non-harmattan period (April – May). The plots of the average electric field against the variation of the environmental factors were used as the qualitative analytical tools and conclusion was drawn to the fact that the relative variation in the measurement of the electric field within and outside the test location is averagely 0.06KV/cm and dependent on the environmental factors.

Characteristics, calibration and measurement uncertainty of RF field strength meters in the frequency range up to 18 GHz

Abstract. Due to their construction, the devices used for the measurement of electromagnetic fields (radiation monitors) must be calibrated individually. The measurement data obtained are documented in a calibration certificate and the user must take them into account in the uncertainty budget he has to draw up. In addition to the uncertainty contributions of the field representation and of the transfer, other contributions occur which depend on the special constructive features of these devices. When the uncertainty budget is drawn up, it depends on the application and the information about the field structure which contributions will have an effect and which will not. The procedure will be explained by an example.

CCEM.RF-K20: Comparison of electrical field strength measurements

The comparison 'EUROMET-Project Nr 520', which started in April 1999 under the responsibility of the Swiss Federal Office of Metrology, was extended to a GT-RF comparison 'CCEM-RF-K.20' which officially started in September 2000, with more participants. The goal of this comparison was to assess the capability of each participating laboratory to measure electromagnetic field strength by calibrating a circulated field strength meter in the frequency range 10 MHz to 1 GHz. The comparison has been interrupted and further continued and ended finally in September 2004 when we received the measurements from all participants. This document presents the results of this comparison in the form of a Final Report.Despite the fact that the probe may have suffered instabilities during the five-year duration of this exercise, we consider that the results of all participants are consistent with the claimed uncertainty. The results support the equivalence of national standards laboratories for realization of field strength in the frequency range 10 MHz–1000 MHz.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Electromagnetic field level temporal variation in urban areas

Temporal variations of electric field levels have been continuously monitored over a period of a week at seven different urban locations and the results are presented and analysed. It has been found that the electric field level exhibits an important random variation with time. From the results analysis, it can be concluded that a single 'snapshot' measurement using a broadband field strength meter could underestimate the maximum averaged values by up to 9 dB. In urban environments, a continuous field meter using a portable datalogger would be required to obtain accurate measurements. Alternatively, compliance with the radiation limits for 99% of the time can be guaranteed from a single 'snapshot' measurement provided that an additional 8 dB margin under the maximum permissible values is considered.

Mobile radio propagation path loss studies at VHF/UHF bands in Southern India

Field strength measurements at 200, 400 and 450 MHz (VHF/UHF band) were conducted with the field strength meter placed on board a vehicle in Southern India. Observed field strength values were converted into path losses and are compared with different path loss prediction methods like Hata (1980), Egli (1957), Blomquist-Ladell (1974), COST 231 Walfisch-Ikegami (Doble 1996), Walfisch-Bertoni (1988) and ITU-R. These path loss studies are carried out in urban, suburban and open areas in this region. The results showed that Hata's method gave better agreement with observed values in urban, suburban and open regions; the COST 231 Walfisch-Ikegami model is also in good agreement with the observed values in urban and suburban regions, the Egli and Blomquist-Ladell methods showed moderate agreement in open regions only. The agreement of the Walfisch-Bertoni and ITU-R methods with observed values is not good.