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With the increasing number of subscribers in mobile communications there is a growing interest in propagation models for the mobile radio channel in urban scenarios and inside buildings. Because of the increasing transmission rates propagation models should be able to predict the field strength coverage as well as the wideband properties for these scenarios.

With the growing interest for broadband mobile services in 3rd generation mobile communication networks, the investigation of radio transmission into vehicles and buildings is getting more important. Models for the propagation into vehicles and buildings enable the calculation of the field strength or received power inside these objects. The inner structure of the vehicles (e.g. metal parts) and buildings (inner walls, furniture) as well as the surroundings (other vehicles, buildings) must be considered, and also different construction materials must be taken into account. A deterministic ray tracing approach has been developed, enabling the computation of the transition from an urban scenario to an indoor scenario and vice versa, thus allowing a very accurate computation of the field strength or received power inside vehicles or buildings. Due to the ray tracing technique, the approach can also be utilized to evaluate wideband properties of the mobile radio channel by computing its impulse response. In order to validate such propagation models, measurements inside and outside a building were made.

With the growing interest for broadband mobile services in 3rd generation mobile communication networks, the investigation of radio transmission into vehicles and buildings is getting more important. Models for the propagation into vehicles and buildings enable the calculation of the field strength or received power inside these objects. The inner structure of the vehicles (e.g. metal parts) and buildings (inner walls, furniture) as well as the surroundings (other vehicles, buildings) must be considered, and also different construction materials must be taken into account. A deterministic ray tracing approach has been developed, enabling the computation of the transition from an urban scenario to an indoor scenario and vice versa, thus allowing a very accurate computation of the field strength or received power inside vehicles or buildings. Due to the ray tracing technique, the approach can also be utilized to evaluate wideband properties of the mobile radio channel by computing its impulse response. In order to validate such propagation models, measurements inside and outside a building were made.

A new model for the field strength prediction for mobile communication networks inside buildings is presented. The model is based on artificial neural networks, trained with measurements. In contrast to other neural prediction models a good generalization is achieved, so the prediction results are also very accurate in buildings not used for the training of the neural network. Two algorithms for the selection of the training patterns for the neural networks are presented and compared to each other.

With the introduction of wireless broadband services in indoor environments there is a growing interest in propagation models for the mobile radio channel inside buildings. Because of the increasing transmission rates propagation models should be able to calculate the field strength coverage as well as the wideband properties for these indoor scenarios. This paper presents a new ray optical approach, which enables the prediction of field strength, delay spread and impulse response within a very short computation time. Additionally, simulation results gained with the new model are compared to measurements of the different wideband channel parameters.

A new model for the field strength prediction for mobile communication networks inside buildings is presented. The model consists of a neural network, trained with measurements and combines the advantages of empirical models (short computation time) with the advantages of deterministic models (waveguiding). The prediction results compare favourably with measurements.