Experimental Determination of Penetration Loss into Multi-Storey Buildings at 900 and 1800MHz

This study presents building pentration loss into and around multi-storey buildings at 900 and 1800MHz based on experimental data obtained through drive test, using Test Mobile System (TEMS) investigation tools. The received signal level was measured inside and outside three buildings; the Senate building of the University of Lagos (B1), Mike Adenuga Towers (B2) and the Sapetro Towers (B3) located in Victoria Island, Lagos Nigeria. The building penetration loss (BPL) was derived from measurements, and the average and standard deviations of the BPL were computed. Results showed that the average BPL of 17.0dB and 13.8dB obtained from building B1 at 900 and 1800MHz, respectively, are comparatively higher than those of buildings B2 and B3. The standard deviation of the BPL shows an increase from 5.2dB at 900MHz to 7.8dB at 1800MHz for building B1, whereas it fell drastically from 8.65dB at 900MHz to 1.40dB at 1800MHz for B2, and a similar behaviour in B1 is seen for building B3 where it rises sharply from 1.55dB at 900MHz to 6.55dB at 1800MHz. This is in agreement with the general trend of increasing penetration loss with increase in frequency except for building B2 where an anomaly is observed. In order to examine the correlation between the measured and the predicted BPL, cubic regression was used to fit a third order polynomial to the measured BPL. Overrall, the fitted models could find useful applications in the design of novel and robust BPL models for modern multi-floored buildings

Characterization of Propagation Path Loss at Vhf/Uhf Bands for Ilorin City, Nigeria

Path loss exponent, standard deviation and building penetration loss are used in all distance path loss models. Once these data are known for an environment, coverage planning and propagation analysis could be done easily. Many countries across the world, such as Japan, United Kingdom, Germany, and the USA have already published their propagation data, mostly, the path loss exponent for their various cities. However in Nigeria, these data are not available. In this work, measurements were conducted at 203.25 MHz and 583.25 MHz frequencies along ten routes in Ilorin City in Kwara State of Nigeria. Least squares regression method is used to fit the measured data with log-normal propagation path loss model to characterize the path loss parameters. Results of the experiment indicate that the path loss exponent for Ilorin City varies from 1.4 to 4.94 with an average value of 2.80. The work further investigates the behaviour of the TV signals in the same environment in terms of standard deviation and building penetration loss across the routes, and some selected building structures

ДОСТАТОЧНЫЙ УРОВЕНЬ МОЩНОСТИ ЭЛЕКТРОМАГНИТНОГО ИЗЛУЧЕНИЯ БАЗОВЫХ СТАНЦИЙ СЕТИ GSM В ГОРОДСКОЙ ЗАСТРОЙКЕ С УЧЕТОМ ЗАТУХАНИЯ РАДИОВОЛН В ЗДАНИЯХ И ВНУТРИСИСТЕМНОЙ ЭЛЕКТРОМАГНИТНОЙ СОВМЕСТИМОСТИ

The results of estimation of required and sufficient levels of radiated power of base stations of cellular communications of GSM standard at the voice communication mode on urban area, taking into account average attenuation of radio waves in buildings and levels of intranetwork interference are given. The analysis is made on the basis of behavior simulation of the fragment of cellular network, executed with the use of multibeam radiowave propagation model and the topological model of a fragment of urban area of the central part of Minsk by comparison of quantiles of statistical distributions of levels of received signals on various floors of buildings and also relative quantity of mobile stations, for which «Signal / (Interference + Noise)» ratio does not exceed a critical threshold of 9 dB, on various floors of buildings at different radiation power of base station. In the modeled urban area of medium number of building storeys the high communication quality is achieved at base station of GSM-1800 networks equivalent isotropic radiated power 43-45 dBm, and is provided by improvement of intrasystem EMC of cellular network at the expense of increase of cluster dimensionality of frequency sharing. Increase of base station radiation power greater than 45 dBm does not lead to improvement of communication quality, but impairs electromagnetic ecology of urban areas.Приведены результаты оценки достаточного уровня излучаемой мощности базовых станций сетей сотовой связи стандарта GSM в режиме телефонной связи в городской застройке с учетом затухания радиоволн в зданиях и уровней внутрисетевых помех. Анализ выполнен на основе имитационного моделирования фрагмента сотовой сети с использованием многолучевой модели распространения радиоволн вне зданий и известных данных о средних значениях затухания радиоволн на различных этажах зданий, а также топологической модели фрагмента городской застройки центральной части Минска. Оценки получены путем сравнения квантилей условных статистических распределений уровней сигналов, а также относительного количества абонентских станций, для которых значение отношения «сигнал / (помеха + шум)» не превышает порога работоспособности, на различных этажах зданий при различной излучаемой мощности базовых станций. В моделируемой части городской застройки средней этажности высокое качество связи достигается при эквивалентной изотропно излучаемой мощности базовых станций GSM-1800 43-45 дБм и обеспечивается улучшением внутрисистемной ЭМС сотовой радиосети, в том числе за счет увеличения порядка кластера частотного планирования. Увеличение мощности излучения базовых станций выше 45 дБм не приводит к улучшению качества связи, но ухудшает электромагнитную экологию городских территорий

Improvement of mobile trilateration accuracy with modified geo-location techniques.

Masters Degree. University of KwaZulu-Natal, Durban.Abstract available in pdf

Radio frequency channel characterization for energy harvesting in factory environments

This thesis presents ambient energy data obtained from a measurement campaign carried out at an automobile plant. At the automobile plant, ambient light, ambient temperature and ambient radio frequency were measured during the day time over two days. The measurement results showed that ambient light generated the highest DC power. For plant and operation managers at the automobile plant, the measurement data can be used in system design considerations for future energy harvesting wireless sensor nodes at the plant. In addition, wideband measurements obtained from a machine workshop are presented in this thesis. The power delay profile of the wireless channel was obtained by using a frequency domain channel sounding technique. The measurements were compared with an equivalent ray tracing model in order to validate the suitability of the commercial propagation software used in this work. Furthermore, a novel technique for mathematically recreating the time dispersion created by factory inventory in a radio frequency channel is discussed. As a wireless receiver design parameter, delay spread characterizes the amplitude and phase response of the radio channel. In wireless sensor devices, this becomes paramount, as it determines the complexity of the receiver. In reality, it is sometimes difficult to obtain full detail floor plans of factories for deterministic modelling or carry out spot measurements during building construction. As a result, radio provision may be suboptimal. The method presented in this thesis is based on 3-D fractal geometry. By employing the fractal overlaying algorithm presented, metallic objects can be placed on a floor plan so as to obtain similar radio frequency channel effects. The environment created using the fractal approach was used to estimate the amount of energy a harvesting device can accumulate in a University machine workshop space