tion CHAPTER 4.7 Parameter Calibration (Erj, Indoor Time Delays 3D RT Environment Prediction Directional CIR Time Resolution Model Pulse Extraction Space Resolution Directional Measurements Directional Cross-correlation Figure 4.7-7 Iterative technique for EM parameter determination. account to determine path attenuation. The distinction prediction is concerned, the active area is limited to the between the main structures and the light partitions is obstacles around and between the radio terminals, there- incorporated in the building database. The analysis of the fore the active area can easily be 'guessed' using rule-of- hybrid radio networks (coverage and QoS) requires the thumb considerations. On the contrary, when the time outdoor and indoor predictions to be done in a unique and angle distribution of the multipath is to be deter- geographical system. Hence both kinds of terrain mod- mined, even far, but prominent, obstacles can have a sig- elling, the outdoor map data and the 3D building rep- nificant impact on prediction results, and therefore a resentation have to be perfectly adjusted. Land usage scientific criterion is needed. A method to attain this aim data is also considered where available. The indoor rep- is presented in [DeFA04]. The method is based on the resentation that is derived from architect plans is gen- idea of running a rough, heuristic field prediction model erally available in a local coordinate system. Successive aimed at identifying the 'active' building set. The basic isometric transformations must be used to adjust the assumption is that paths experiencing a single (or two) local representation to the building contours in the out- interaction(s) with building walls (often referred to as door map data. Mixed database handling issues are also 'first (second) order rays') are likely to be more relevant addressed in [KüMe02] and [KEGJ03]. In the former than rays experiencing multiple interactions, since paper, empirical models for outdoor to indoor penetra- more interactions correspond