Wednesday August 29, 2007

 

 


Lecturer: Mr. Sandro Scalise and Prof. Vittorio Degli Esposti

DLR, Oberpfaffenhofen (Germany) / University of Bologna (Italy)
e-mail: Sandro.Scalise@dlr.de - vdegliesposti@deis.unibo.it

Title: Propagation and Packet Error Models for Mobile Wireless Channels

Abstract: A good understanding of the impairments introduced by the propagation channel is of paramount importance in the design of a satellite-based communications system. The relevant sources of channel impairments depend upon several factors, among them the considered scenario (e.g. mobile vs. fixed terminals, rural vs. urban etc…), the carrier frequency and the employed access scheme. For instance, effects like shadowing and blockage are typical of mobile reception. On the other hand, atmospheric attenuation phenomena can be safely disregarded at frequency bands below some GHz, whereas they start to become relevant as the carrier frequency increases.
Since terminals are often located in urban areas, where also repeaters and gap fillers may be adopted, also terrestrial, multipath propagation represents a major concern. Urban multipath propagation and its impact on the radio channel characteristics will be therefore addressed, with a particular focus on deterministic models such as ray tracing.
Furthermore, a formal methodology to derive packet error models complementing a purely propagational model with considerations related to the adopted waveform and coding scheme will be presented.
Each of the main parts of this lecture will be organized as an independent module. In general, the main focus will be on specific results and considerations derived by models and measurements, rather than on reviewing the well-known theory of channel characterization and modelling. Nevertheless, the most important definitions will be recalled for the sake of clarity and adequate references provided.
The lecture will be concluded by a short talk concerning the ongoing revision of DVB-RCS standard towards the full support of mobility.

Downloads:

1. Part1

2. Part2

3. Part3

4. Part4

5. Part5

6. Part6

7. Part7

8. Test

Information

Video files are in .mp4 format. Each part is about 280Mb @ VGA resolution (640x480). If your video player doesn't work, you can download the freeware vlc player here.