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This thesis examines methods to enhance the realism of signal strength simulations in a Radio Access Network (RAN) test environment by identifying and analyzing factors that influence signal strength in actual RAN settings. The study addresses different attenuation impacts using three technical reports: 3GPP TR 38.901 for path loss in various area scenarios, ITU-R P.838 for rain attenuation, and ITU-R P.840 for cloud and fog attenuation effects. This thesis also considers inter-cell interference as a proof of concept to understand its impact on signal quality. Key findings indicate that path loss substantially affects signal strength, significantly influenced by frequency, distance between transmitter and receiver, and the environmental context (e.g., rural or urban). Although rain and cloud attenuation also affect signal strength, their impact is minor but increases with higher frequencies. This thesis enriches our understanding of more accurately simulating signal strength in RAN environments by focusing on path loss, rain, cloud attenuation, and inter-cell interference. This work lays a foundation for subsequent studies to expand upon, particularly in integrating diverse attenuation factors, thereby driving forward the precision and reliability of future RAN simulations.

Thesis (MScEng)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: A new type of wideband lters, with tunability in both the centre frequency and bandwidth, is presented in this thesis. These lters are based on perturbed ring-resonators in cascade, while varactor diodes are used for electronic tuning. The Karoo Array Telescope (KAT-7) requires a front-end lter that has the ability for ne-tuning the response after fabrication, in order to obtain the designed ltering response. Not only are tune-all characteristics required, but also wide bandwidth, at passband, high selectivity and implementation in microstrip technology. In this thesis an extensive investigation of both tunable and wideband lters is done, in order to nd a possible solution for the KAT-7 speci cations. Following this investigation, it is concluded that no suitable design approach for tune-all wideband lters, implemented in microstrip, exists in current literature. Therefore, this thesis proposes a new type of lter along with the development of a complete design procedure. Two lters are designed with this procedure to achieve the required passband from 1.2 to 1.95 GHz (i.e. a fractional bandwidth of 49%). In the rst lter design, with a network consisting of 4 cascaded ltering-sections, the centre frequency is 5% tunable and the bandwidth 17.5%. With the second lter consisting of 6 cascaded ltering-sections, higher selectivity is achieved but with lower return loss. Here the centre frequency is 8.5% tunable and the bandwidth 18.8%. The theoretical results are validated with the fabrication of both lters. This design is very unique in that it achieves wide bandwidth, is realisable in microstrip and most importantly is tunable in both the centre frequency and bandwidth. An advantage of this design procedure is that full wave simulations are minimal, due to the complete circuit models used for optimisation. / AFRIKAANSE OPSOMMING: 'n Nuwe soort van wye-band lters, met verstelbaarheid in beide senter frekwensie en bandwydte, word voorgelê in hierdie tesis. Hierdie lters is gebaseer op versteurde ringresoneerders in kaskade, terwyl varaktordiodes gebruik word vir elektroniese verstelling. Die Karoo Array Telescope (KAT-7) vereis 'n voorkant lter wat die vermoë het vir die instemming van die respons na fabrikasie, sodat die geontwerpde lter respons behaal kan word. Nie net word verstel-als eienskappe vereis nie, maar ook wye bandwydte, plat deurlaatband, hoë selektiwiteit en implimentering in mikrostrook tegnologie. In hierdie tesis is 'n veelomvattende ondersoek gedoen van beide verstelbare en wyeband lters, sodat 'n moontlike oplossing vir die KAT-7 spesi kasies gevind kan word. Na aanleiding van hierdie ondersoek, is die gevolgtrekking dat daar geen gepaste ontwerp benadering vir verstel-als wye-band lters, wat geïmplimenteer is in mikrostrook, in huidige literatuur bestaan nie. Daarom stel hierdie tesis, saam met die ontwikkeling van 'n volledige ontwerp prosedure, 'n nuwe tipe lter voor. Twee lters is ontwerp met hierdie prosedure om die vereiste deurlaatband vanaf 1.2 tot 1.95 GHz (dit is 'n fraksionele bandwydte van 49%) te behaal. In die eerste lter ontwerp, met 'n netwerk wat uit 4 kaskade lter-seksies bestaan, is die senter frekwensie 5% verstelbaar en die bandwydte 17.5%. Met die tweede lter bestaande uit 6 kaskade lter-seksies, word hoër selektiwiteit behaal maar met laer eggoverswakking. Hier is die senter frekwensie 8.5% verstelbaar en die bandwydte 18.8%. Die teoretiese resultate is geldig bewys deur die fabrikasie van albei lters. Hierdie ontwerp is baie uniek in dat dit wye bandwydte behaal, is realiseerbaar in mikrostrook en mees belangrikste dat dit verstelbaar is in beide senter frekwensie en bandwydte. 'n Voordeel van hierdie prosedure is dat heelgolf simulasies minimaal is, a.g.v. die volledige stroombaan modelle wat gebruik word vir optimering.

This thesis deals with issues of automatic quality estimation of ECG signals. The main aim of this thesis is to implement own algorithm for classifying ECG signals into three classes of quality. Theoretical part of the thesis contains mostly description of recording electrical activity of the heart, anatomy and physiology of the heart, electrocardiography, different types of ECG signals interference and two of the chosen methods for quality estimation. Implementation of the chosen methods is presented in the practical part. Result of this thesis are two implemented algorithms, which are based on methods described in the theoretical part. The first of two is based on detection of R-waves, validation of physiological assumptions and the subsequent calculation of the correlation coefficient between adaptive template and interfered signal. Second is based on calculation of a continuous SNR value over time, which is then thresholded. The robustness of the methods was verified on the three specified real ECG signals, which are all available on UBMI including annotation of specific signal parts. Those 24-hour long signals were recorded by Holter monitor, which is described in the theoretical part of the thesis. Achieved results of individual methods, including their comparison with annotation and statistical evaluation are presented in the conclusion of this thesis.

The thesis provides an analysis of the ECG signal, focusing on the possible types of interference occuring in the signal. These types of interference are closely examined and their realization in the MATLAB programming environment is characterized. The SPIHT algorithm is introduced and the possibilities of its use are discussed. Futher, the application of this algorithm to the ECG signal containing individual types of interference generated by means of the designed interference generator is described and the impact of the SPIHT algorithm on the specific types of signal interference is analyzed. Finally, the obtained results are evaluated.