One channel model that characterises multipath fading effect of a wireless channel is called Flat Rayleigh Fading channel model. Given the properties of Flat Rayleigh Fading channel, an equation to find the capacity of a Flat Rayleigh fading channel with hard decision decoding is derived. The difference of power requirement to achieve the Additive White Gaussian Noise (AWGN) capacity over a Flat Rayleigh Fading channel fading is found to increase exponentially with Es /N0 . Upper and lower bounds of error performance of linear block codes over a Flat Rayleigh Fading channel are also studied. With the condition that the excess delay of a channel is known earlier, it is shown that a correlator with shorter length, according to excess delay of the channel, can be constructed for use in wireless channel response measurements. Therefore, a rule of construction of a shorter length correlator is defined, involving concatenation of parts of a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence. Simulation of [136,68,24] Double Circulant Code with Dorsch List Decoding is also done in order to evaluate error performance of the channel coding scheme over one of the IEEE Wireless Metropolitan Area Network (WirelessMAN) channel models, the Stanford University Interim Channel Model No. 5 (SUI-5) channel. Performance of the channel cod- ing was severely degraded over the SUI-5 channel when it is compared to its performance over the AWGN channel. Indoor path losses within three multifloor office buildings were investigated at 433 MHz, 869 MHz and 1249 MHz. The work involved series of extensive received signal strength measurements within the buildings for all of the considered frequencies. Results have shown that indoor path loss is higher within a square footprint building than indoor path loss in a rectangular building. Parameters of Log-Distance Path Loss and Floor Attenuation Factor Path Loss models have been derived from the measurement data. In addition, a new indoor path loss prediction model was derived to cater for path loss pre- diction within multifloor buildings with indoor atriums. The model performs with better prediction accuracy when compared with Log-Distance Path Loss and Floor Attenuation Factor Path Loss models.

In this thesis it is investigated to what extent it is possible to accurately model path loss in indoor environments using a simple empirical approach. Two kinds of radio access antenna deployments are investigated: 1) standard dipole antennas and 2) leaky cables. For the case of standard dipole antenna deployment, a few well established empirical models are integrated in order to account for the main observed propagation mechanisms. One important propagation mechanism is wave guiding in corridors. It has been shown that a model designed for street microcells (“The recursive model”) combined with the power law model (combined model) well describes this wave guiding propagation. Some inaccuracies have, however, been observed when the direct pathway is dominating. In this master thesis it is therefore investigated if the model accuracy may be improved by integration of the Keenan-Motley and the Devasirvatham model (modified combined model) accounting for loss due to obstructions along the direct pathway. In this work, the primary models used for the case of leaky cable antenna deployments are the Keenan-Motley model (for short distances) and the modified combined model (for large distances). In order to improve and evaluate the modeling, propagation measurements have been carried out at the 2.44 GHz band in an indoor office environment. The measurement data, i.e., the calibrated frequency response of the channel, is obtained using the network analyzer measurement technique by sweeping the frequency over a range of 80 MHz around the center frequency. Hence, the path gain measured in dB-scale is obtained as the difference between the transmitted power and the received power. The combined model and the modified combined model are evaluated and parameterized based on the conducted measurements. The accuracy of the combined model is improved by the implemented modifications. In our case, the standard deviation error is reduced from 5-19 dB to 2-4 dB. Moreover, the measurements show that using leaky cables results in a better coverage in rooms alongside the corridor compared with using dipole antennas. Also the interference into adjacent cells is reduced using leaky cables compared with using dipole antennas.

The objective of this work is to enhance the awareness of the indoor propagation behaviour, by a set of investigations including simulations and measurements. These investigations include indoor propagation behaviour, local mean power estimation, proposing new indoor path loss model and introducing a case study on 60 GHz propagation in indoor environments using ray tracing and measurements. A summary of propagation mechanisms and manifestations in the indoor environment is presented. This comprises the indoor localization techniques using channel parameters in terms of angle of arrival (AOA), time of arrival (TOA) and received signal strength (RSS). Different models of path loss, shadowing and fast fading mechanisms are explored. The concept of MIMO channels is studied using many types of deterministic channel modelling such as Finite Difference Time Domain, Ray tracing and Dominant path model. A comprehensive study on estimating local average of the received signal strength (RSS) for indoor multipath propagation is conducted. The effect of the required number of the RSS data and their Euclidian distances between the neighbours samples are investigated over 1D, 2D and 3D configurations. It was found that the effect of fast fading was reduced sufficiently using 2D horizontal’s arrangement with larger spacing configuration. A modified indoor path loss prediction model is presented namely effective wall loss model (EWLM). The modified model with wall correction factors is compared to other indoor path loss prediction models using simulation data (for 2.4, 5, 28, 60 and 73.5 GHz) and real-time measurements (for 2.4 and 5 GHz). Different operating frequencies and antenna polarizations are considered to verify the observations. In the simulation part, EWLM shows the best performance among other models. Similar observations were recorded from the experimental results. Finally, a detailed study on indoor propagation environment at 60 GHz is conducted. The study is supported by Line of Sight (LoS) and Non-LoS measurements data. The results were compared to the simulated ones using Wireless-InSite ray tracing software. Several experiments have confirmed the reliability of the modelling process based on adjusted material properties values from measurements.