Satcom

STATUS: Finished

Concise project description

The PECS-Satcom project (complete title "Building Penetration Measurement and Modelling for Satellite Communications at L, S and C-Band") was run by the Faculty of Electrical Engineering at the Czech Technical University in Prague. This two-year project started in January 2009 and successfully finished in December 2010 following the original plan laid out in the project proposal. An extensive measurement campaign, covering a representative set of typical buildings in an urban area and aimed at building penetration loss for satellite services at L-, S- and C-band, was performed in Prague in the summer of 2009. Based on a thorough analysis of the resulting experimental data, new elevation dependent empirical models were introduced at corresponding frequencies. The results were published as journal [1][2] and conference papers.

Detailed project description

As the project required carrying out a measurement campaign to obtain relevant experimental data, the proposed measurement method was based on the previous trials with a remote controlled airship, but significant improvements to achieve a new quality of results were made including development of new transmitter and receiver stations (Fig. 1 and 2). In order to thoroughly characterize building penetration loss, a representative set of five typical buildings in an urban area were selected in Prague (Fig. 3) and corresponding penetration loss trials were performed. To calculate penetration loss using the experimental data obtained during the in-building measurements, a so-called reference level had to be used. As there was no standardized definition of penetration loss available, the measurement system was calibrated on a flat open field. Further, to enable a comparison with other definitions of penetration loss, reference measurements were taken also at street level close to a wall of one of the case-study buildings and on most roofs of the five buildings.

Fig.1: Transmitter station

The theoretical part of the project started by the review of existing models for the satellite-to-indoor propagation channel. Selected models were later validated and compared with the obtained experimental data and the new derived empirical models. For these purposes, the experimental data were statistically processed and categorized at first, namely to investigate building penetration loss as a function of frequency, elevation angle, azimuth angle with respect to the building orientation, floor number with respect to surrounding roof heights, position within the indoor environment, type of the building and its surroundings, and receiver antenna orientation. Each measurement scenario was thoroughly investigated to identify all the known/predicted effects influencing the wave propagation. The theoretical part of the project followed both the statistical/empirical approach to provide efficient models for propagation modelling as well as deterministic approach to understand the wave propagation mechanisms of the satellite-to-indoor channel.

Fig.2: Receiver station

The measurement trials were carried out according to Fig. 4. After selecting the measurement positions inside each of the case-study buildings, which covered different floor levels and different distances of the receiver from a window/wall, four fly-overs of the airship separated by 45° in azimuth were planned above each measurement site. The length of the fly-overs was determined by the requirement to cover a wide range of elevation angles from 25° to 90°. All the experimental data were carefully sorted out and penetration loss was calculated for each measurement site by using the open-flat-field calibration. Then, it was possible to analyse penetration loss not only for each measurement site, but also for the whole building by calculating its average penetration loss.  Based on these characteristics, corresponding empirical models were proposed for L-, S- and C-band and both the models and experimental data were compared with results from previous trials. The results were published as journal papers in [1] and [2] and presented at several conferences.

Fig.3: Five buildings in Prague which were used for the measurement campaign

Resume of activities done in 2009
The volume of work implemented in 2009 followed the original plan laid out in the project proposal. The corresponding key milestones were attained: accomplishment and planning of the measurement setup, the measurement campaign itself, accomplishment of basic processing of the raw measured data.
The work packages 1 (Review of models and definition of preliminary model structure), 2 (Preparation of the measurement campaign), 3 (Building penetration measurement campaign), and 4 (Measurement data processing) were successfully finished in time and reported to ESA.

Resume of activities done in 2010
Based on the results of the project, selected measurement trials were repeated in 2010 to extend the experimental datasets for further processing and analyses. Detailed analyses of the experimental data together with the proposed empirical models were presented in WP5 (Building penetration modelling), and work packages 1-4 were updated. The project was finished in December 2010 by a final presentation held at ESA/ESTEC and delivery of the experimental data.

Fig.4: Experimental setup

[1] M. Kvicera, P. Horak, P. Pechac, F. Perez-Fontan, “On a definition of building penetration loss for high elevation angles,” IEEE Transactions on Antennas and Propagation. 2010, vol. 58, no. 12, p. 4115-4118.

[2] M. Kvicera, P. Pechac, “Building penetration loss for satellite services at L-, S- and C-band: measurement and modeling,” Accepted to IEEE Transactions on Antennas and Propagation, December 2010.

Project Duration: 2009-2010
Approved budget: 97 400 EUR
Principal Investigator: Pavel Pechač
Address: Czech Technical University in Prague, FEE
166 27  Praha 6
pechacfel.cvut.cz