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DVB-H networks allow high data rate broadcast access for hand-held terminals. Building penetration loss measurements of a DVB-H signal at 602 MHz are performed in 100 buildings in Belgium. Buildings are categorized in different types (office buildings, apartments, villas, mansions, row houses, stations) and the rooms are classified according to the number of outside radiated walls. The cumulative distribution function of the penetration loss is determined and lognormality is investigated. Models are developed to calculate the penetration loss as a function of the number of radiated walls. Also models for apartments as a function of the floor level are developed. This research enables the calculation of indoor coverage probability for wireless networks. Index Terms--Buildings, digital video broadcasting-handheld, DVB, DVB-H, indoor, indoor reception, penetration loss, physical layer.

Electromagnetic exposure of the general public due to large substations transforming voltages of 150 and 36 kV to 11 kV is investigated and safety distances for these substations have been determined. In total, 142 field measurements were executed for two substations: 91 measurements of the magnetic field and 51 measurements of the electric field. Measured momentary magnetic-field values are within the range of 0.051 to 13.17 [micro]T. The levels of the electric field are within the range of 0.095 to 270.0 V/m. The cumulative distribution function of the measured magnetic-field values has been determined, and it is shown that the fields excellently follow a lognormal distribution. The maximal magnetic- and electric-field values for all the investigated substations are below 100 [micro]T (values over a day and year) and 5 kV/m, respectively. When comparing the average exposure with the value of 0.4 [micro]T, safety distances of maximally 8.1 m (average day) and 7.1 m (average year) are obtained. Index Terms--Electric and magnetic field, electromagnetic (EM) measurement, exposure of general public, extremely low frequency (ELF), safety distance, substation.

DVB-H networks allow high data rate broadcast access for hand-held terminals. A method to analyze the performance is developed. The influence of different MPE-FEC rates and modulation schemes on the performance of a DVB-H network is analyzed in this paper for 9 different reception conditions. Portable (indoor and outdoor) and mobile reception (car, train, tram, bus) are investigated. This analysis enables better estimations of the performance of DVB-H systems and an optimized DVB-H performance model. The percentage of valid reception, MPE-FEC gains, carrier to interference-plus-noise ratios, and minimal signal strengths for the different reception conditions and modulation schemes are presented. Index Terms--Digital video broadcasting--handheld, DVB, DVB-H, indoor reception, mobile reception, modulation scheme, MPE-FEC, physical layer, reception condition, reception quality.

A procedure to optimize the coverage and throughput for a DVB-H system is proposed. The performance of the system is evaluated by measurements for different modulation schemes, guard intervals, and MPE-FEC rates. Based on technical trial results, an optimal transmission scheme is proposed for a specific network, maximizing the coverage for a certain throughput requirement. This optimization will enable to select an optimal transmission scheme for future DVB-H trials and deployments. Index Terms--Coverage, digital video broadcasting-handheld, DVB, DVB-H, indoor reception, mobile reception, MPE-FEC, optimization, throughput.

A method for accurate determination of electromagnetic fields around the Worldwide Interoperability for Microwave Access (WiMAX) base stations (BSs) is developed in this paper. The influence of the characteristics of the WiMAX signal on the settings and parameters of the spectrum analyzer (SA) used for exposure assessment is investigated. Optimal settings of the SA are proposed, and the results obtained using simulations and measurements agree very well. A practical application in the neighborhood of a WiMAX BS is performed. The obtained electric field values correspond very well for the different settings and are compared with the reference levels for the general public and those for occupational exposure. The results of this paper can be used for practical measurement procedures of the exposure due to WiMAX signals. Index Terms--802.16-2004, electromagnetic measurement, electromagnetic radiation, exposure assessment, spectrum analyzer (SA), Worldwide Interoperability for Microwave Access (WiMAX).

Measurements and simulations of the vehicle penetration loss (VPL) at 600, 900, 1800, and 2400 MHz are presented. The measured average penetration loss varies from 3.2 to 23.8 dB, depending on frequency, illuminated vehicle side, and in-vehicle antenna orientation. VPL tends to follow a lognormal distribution. Reported penetration loss values are compared to previous measurements from the literature. Index Terms--Antenna orientation, coverage, measurement, simulation, vehicle penetration loss (VPL).

A low-cost measurement method for the extraction of the relative phases of the field of base station and broadcast antennas is presented. Our purpose is to determine the polarization of the field at a measurement site using magnitude measurements only. By determining six amplitude components using a spectrum analyzer, the polarization ellipse of the field can be obtained. This low-cost method can be used for outdoor measurements, which is not possible with network analyzers. Using this method and thus knowing the polarization of the incident field we are able to determine more accurately the actual electromagnetic power absorbed in people at a measurement site. Index Terms--Base station antenna, electromagnetic field, measurement, measurement probe, phase extraction, polarization, specific absorption rate (SAR), telecommunication and broadcast antenna.

Abstract DVB-H networks allow high data rate broadcast access for hand-held terminals. A new method to determine the range of good reception quality of such a DVB-H network will be investigated in this paper. To this end, a new subjective criterion is proposed, based on the viewing experience of the users. This criterion is related to the percentage of valid reception. A comparison with existing criteria, based on measured signal strengths, is also made. The ranges are determined for mobile reception inside a car. The influence of the MPE-FEC rate and the modulation scheme on the range is also investigated, enabling wireless telecom operators to select optimal settings for future networks.