The master’s thesis deals with development of the radio channel analyser operating in the unlicensed 2.4 GHz band according to IEEE 802.15.4 standard. The analyzer will contain two basic functions, namely energy detection of channels and analysation of selected channel. Detection of energy will be solved by selection between simple graph and text list on display. Based on information about the occupancy of channels the user can decide which channel would be set up. During the receiving of valid frame the source address, signal strength and signal quality will be stored. At the end the processor will show these data on display. For controlling the device will be installed two LEDs and four buttons.

Tato disertační práce se věnuje lokalizaci v bezdrátových sítích se zaměřením na odhad vzdálenosti. Lokalizace je v bezdrátových sítích s mobilními ale i statickými uzly důležitým procesem, neboť znalost pozice uzlů může být během provozu sítě dále s výhodou využita. V práci je prezentována nová metoda odhadu vzdálenosti na základě měření síly přijatého signálu. Navržená metoda je postavena tak, aby s co nejnižšími energetickými náklady dosáhla požadovaného stupně přesnosti i ve značně odlišných rádiových podmínkách. Před návrhem vlastní metody byla provedena experimentální analýza spotřeby anergie a šíření signálu s jeho využitím pro lokalizační účely. Na základě provedené analýzy byla navržena nová metoda (Adaptabilní energeticky nenáročná metoda odhadu vzdálenosti), která byla následně ověřena v simulátoru a experimentální síti za reálných podmínek.

The purpose of this study is to investigate if individual differences exists between microwave sensors from the same manufacturer and to find which variables of the microwave sensors that can be the reason for those individual differences. To investigate this, an experiment environment was made to gather data from microwave sensors in a repetitive way. This experiment environment was used in three different experiments where individual differences, radiation pattern and noise were measured. As a base for the experiments a literature review was made to find variables that could affect the individual differences. The study shows that individual differences on signal strength can be found on microwave sensors of the type MDU2000 from Microwave solutions. Also, the radiation pattern at higher angles can differentiate. The frequency from the microwave sensors at lower speeds shows no significant difference individually. This study contributes to increased knowledge about individual differences on microwave sensors of the type MDU2000. Results from this study can be used as a recommendation to suitable applications. As both resources and time have been limited during this thesis, the study was limited to only perform tests on microwave sensors of the type doppler radar. Another limit to the study is to only do tests at lower speeds i.e. a maximum speed of 5km/h. / Syftet med denna studie är utreda om individuella skillnader finns mellan mikrovågssensorer från samma tillverkare samt att ta reda på vilka variabler hos mikrovågssensorerna som kan bidra till dessa individuella skillnader. För att ta reda på detta konstruerades en experimentmiljö för att samla in data från mikrovågssensorer på ett repetitivt sätt. Denna experimentmiljö användes i tre olika experiment där individuell skillnad, strålningsmönstret samt brus uppmättes. Som grund till experimenten utfördes en litteraturundersökning för att hitta variabler som kan påverka den individuella skillnaden. Studien visar att individuella skillnader på signalstyrka finns bland mikrovågssensorer av typen MDU2000 från Microwave solutions. Även antennens strålningsmönster vid större vinklar kan skilja. Frekvensen från mikrovågssensorn vid lägre hastigheter visar ingen signifikant skillnad individuellt. Denna studie bidrar till ökad kunskap kring individuella skillnader på mikrovågssensorer av typen MDU2000. Resultat från studien kan användas som rekommendation till lämpliga användningsområden. Då både resurser och tid har varit begränsade under examensarbetet sattes en begränsning till att endast utföra tester på mikrovågssensorer av typen dopplerradar. En till begränsning är att endast göra tester på låga hastigheter d.v.s. maximalt 5km/h.

Wireless devices search for access points when they want to connect to a network. A devicechooses an access point based on the received signal strength between the device and theaccess point. That method is good for staying connected in a local area network but it doesnot always offer the best performance, which can result in a slower connection. This is thestandard method of connection for wireless clients, which will be referred to as the standardprotocol. Larger networks commonly have a lot of access points in an area, which increasesthe coverage area and makes loss of signal a rare occurrence. Overlapping coverage zonesare also common, offering multiple choices for a client. The company Inteno wanted an alternativeconnection method for their gateways. The new method that was developed wouldforce the client to connect to an access point depending on the bitrate to the master, as wellas the received signal strength. These factors are affected by many different parameters.These parameters were noise, signal strength, link-rate, bandwidth usage and connectiontype. A new metric had to be introduced to make the decision process easier by unifying theavailable parameters. The new metric that was introduced is called score. A score system wascreated based on these metrics. The best suited access point would be the one with the highestscore. The developed protocol chose the gateway with the highest bitrate available, while thestandard protocol would invariably pick the closest gateway regardless. The developed protocolcould have been integrated to the standard protocol to gain the benefits of both. Thiscould not be accomplished since the information was not easily accessible on Inteno’s gatewaysand had to be neglected in this thesis. / Trådlösa enheter söker efter accesspunkt när de vill ansluta till ett nätverk. En enhet väljer enaccesspunkt beroende på den mottagna signalstyrkan mellan enheten och accesspunkten.Denna metod medför en stabil uppkoppling i ett lokalt nätverk, men medför inte alltid bästamöjliga prestanda, vilket kan resultera i en långsammare anslutning till Internet. Detta ärstandard uppkopplings metod för trådlösa klienter, vilket kommer refereras som standardprotokollen. Större nätverk har vanligtvis en mängd olika accesspunkter i ett område, vilketgör att signalstyrkan sällan förloras. Överlappande täckningsområden är också vanliga ochger en klient flera alternativa accesspunkter att välja mellan. Företaget Inteno ville tacklaproblemet genom att skapa en ny anslutningsmetod för deras nätverksnoder. Den nya metodenskulle tvinga klienter att ansluta sig till en accesspunkt beroende på bithastigheten mothuvudnoden, så väl som den mottagna signalstyrkan. Faktorerna påverkas av många olikaparametrar. Parametrarna var, brus, signalstyrka, länkhastighet, dataanvändning och anslutningstyp.Ett nytt mått behövde införas för att göra beslutsprocessen enklare, genom att förenade tillgängliga parametrarna. Det nya måttet som infördes var poäng. Ett poängsystemskapades och baserades på de önskade värdena. Den accesspunkten med högst poäng erbjödden bästa uppkopplingen till huvudnoden. Det utvecklade protokollet valde nätverksnodenmed den högsta överföringshastighet som var tillgänglig, medan standardprotokollet alltidvalde den närmaste nätverksnoden utan hänsyn till andra faktorer. Den utvecklade protokolletkunde ha integrerats med standardprotokollet för att utnyttja fördelarna av bägge protokollen.Detta var inte möjligt eftersom informationen inte var lättåtkomlig på Intenos nätverksnoderoch fick försummas i avhandlingen.

Examensarbetet genomfördes tillsammans med företaget Rol Ergo. Syftet med studien var att analysera Zigbee 3.0 och Bluetooth Low Energy 5.2 och deras lämplighet i tidskritiska system genom att studera latensen och förhållandet mellan signalstyrkan och avståndet mellan de två kommunikationsprodukter. Datainsamlingen genomfördes med en experimentell studie och utifrån kunskap som framskaffats har ett visst antal bestämda experiment utförts för att svara på frågeställningarna som ställs.  Datainsamlingen visar att både maxlatensen och typiska latensen hos Zigbee är lägre än maxlatens och typiska latens för Bluetooth Low Energy. Datainsamlingen för signalstyrkan visar att Bluetooth Low Energys signalstyrka blir mer påverkad av avståndet mellan kommunikationsprodukterna än vad Zigbees blir. Det visar även att den optimala förhållande mellan signalstyrkan och avståndet hos Zigbee är bättre än hos Bluetooth Low Energy.  Slutsatsen av arbetet är att Zigbee är mer lämpad för tidkritiska system än Bluetooth Low Energy då låg latensen prioriteras. Zigbee är även mer lämpad då lång distansen prioriteras men då bör signalstyrkan ligga runt -50dBm. Bluetooth Low Energy är dock mer lämpad då lång distans inte prioriteras och signalstyrkan inte behöver vara utmärkt för att kunna kommunicera.  Begränsningarna för arbetet är att Bluetooth Low Energy och Zigbee endast har prövats på utvecklingskortet nRF5340 DK.  På grund av den begränsade tiden så har endast ett antal bestämda experiment som har föreslagits av rådgivare på Rol Ergo utförts. / The thesis has been conducted together with  Rol Ergo company. The purpose of this study is to analyse Zigbee 3.0 and Bluetooth Low Energy 5.2 and their suitability for time-critical systems, by studying latency and the relations between signal strength and distance between two communication products. The data collection was completed by an experimental study. By using knowledge that has been collected for the study, sets of experiments will be performed to answer the research questions.  Results of the collected data indicate that both the maximum latency and the typical latency for Zigbee is significantly lower than for Bluetooth Low Energy. The collected data for signal strength shows that the signal strength for Bluetooth Low Energy is more affected by distance between the communication product, than Zigbee’s is. It also shows that the optimal ratio between signal strength and distance for Zigbee is better than for Bluetooth Low Energy. The conclusion of the study shows Zigbee to be a more suitable for time-critical systems compared to Bluetooth Low Energy when low latency is being prioritized. Zigbee is also more suitable for time-critical systems when long distance is being prioritized, however the signal strength must then be around -50 dBm. Bluetooth Low Energy is more suitable when long distance is not the priority, and the signal strength does not have to be excellent to be able to communicate.  The limitations for this thesis are that Bluetooth Low Energy and Zigbee will only be tested on the nRF5349 Development Kit. given limited time, only a certain of experiments, whereas some have been suggested by advisors from Rol Ergo, has been carried out.

More and more people choose to watch television online through online video-on- demand services. For media corporations, such as the Modern Times Group (MTG), this means that video-on-demand will become an increasingly important source of revenue. Because video-on-demand is an online service, advertising products offered therein are in competition with other online advertising products. Currently, MTG’s video-on-demand advertising products are the same as on regular television, meaning they haven’t yet taken advantage of any advertising product development opportunities made possible by Internet technology. The purpose of this thesis is therefore to determine what MTG’s strategy should be to improve the competitiveness and revenue of their video-on-demand advertising products, and what key concerns need to be addressed in order to realize the determined strategy. By request of the commissioner, MTG, possible uses of segmentation to achieve the strategy are studied. The methods used to collect data include multiple interviews both at MTG and at their current advertising customers, as well as web analytics and a questionnaire. Both qualitative and quantitative analysis was used to answer the research questions. Findings suggest that MTG should strive to improve the engagement of their advertising products, through the use of contextual segmentation and self-segmentation. This goes against the current trend in online advertising, where segmentation is primarily used for ad targeting. The reason for not adhering to the trend is that MTG’s advertising customers operate in a television mindset, where ad targeting is of a very limited nature and engagement is of greater perceived value.

Call quality has been crucial from the inception of telecommunication networks. Operators need to monitor call quality from the end-user¿s perspective, in order to retain subscribers and reduce subscriber ¿churn¿. Operators worry not only about call quality and interconnect revenue loss, but also about network connectivity issues in areas where mobile network gateways are prevalent. Bandwidth quality as experienced by the end-user is equally important in helping operators to reduce churn. The parameters that network operators use to improve call quality are mainly from the end-user¿s perspective. These parameters are usually ASR (answer seizure ratio), PDD (postdial delay), NER (network efficiency ratio), the number of calls for which these parameters have been analyzed and successful calls. Operators use these parameters to evaluate and optimize the network to meet their quality requirements. Analysis of speech quality is a major arena for research. Traditionally, users¿ perception of speech quality has been measured offline using subjective listening tests. Such tests are, however, slow, tedious and costly. An alternative method is therefore needed; one that can be automatically computed on the subscriber¿s handset, be available to the operator as well as to subscribers and, at the same time, provide results that are comparable with conventional subjective scores. QMeter® ¿ a set of tools for signal and bandwidth measurement that have been developed bearing in mind all the parameters that influence call and bandwidth quality experienced by the end-user ¿ addresses these issues and, additionally, facilitates dynamic tariff propositions which enhance the credibility of the operator. This research focuses on call quality parameters from the end-user¿s perspective. The call parameters used in the research are signal strength, successful call rate, normal drop call rate, and hand-over drop rate. Signal strength is measured for every five milliseconds of an active call and average signal strength is calculated for each successful call. The successful call rate, normal drop rate and hand-over drop rate are used to achieve a measurement of the overall call quality. Call quality with respect to bundles of 10 calls is proposed. An attempt is made to visualize these parameters for better understanding of where the quality is bad, good and excellent. This will help operators, as well as user groups, to measure quality and coverage. Operators boast about their bandwidth but in reality, to know the locations where speed has to be improved, they need a tool that can effectively measure speed from the end-user¿s perspective. BM (bandwidth meter), a tool developed as a part of this research, measures the average speed of data sessions and stores the information for analysis at different locations. To address issues of quality in the subscriber segment, this research proposes the varying of tariffs based on call and bandwidth quality. Call charging based on call quality as perceived by the end-user is proposed, both to satisfy subscribers and help operators to improve customer satisfaction and increase average revenue per user. Tariff redemption procedures are put forward for bundles of 10 calls and 10 data sessions. In addition to the varying of tariffs, quality escalation processes are proposed. Deploying such tools on selected or random samples of users will result in substantial improvement in user loyalty which, in turn, will bring operational and economic advantages.

M. Tech. (Department of Information Technology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Tracking involves information gathering, manipulation and proving information on the location of a set item. Many single or hybrid technologies – Global Positioning System (GPS), Radio Frequency (RF), Bluetooth (BLT) or Wireless Fidelity (WiFi) – have been used to provide tracking information of an asset of interest. The use of hybrid technology in tracking assets has proven to be effective if the selection of the technologies used is done correctly. This study used a hybrid of GPS and Radio Frequency technologies to track assets of interest because of their characteristics for use inside and outside a building. In this study GPS geo-fencing was used and time interval was used to receive data from the technology. Heuristic methodology, which enabled us to divide a room into sections, was used, where testing was done in sections in a room with different types of material, such as bricks, wood or metal, and the RF signal degradation, called attenuation, was measured. A straight-line distance and a sum of distances at 30-minute intervals were calculated to determine how far the asset had travelled from the point of origin to the new position. A distance of less than 10 metres was ignored. Geofencing was used to trigger an event since it indicates that the asset has crossed the permitted boundary. An RF reader was placed at the door to identify when the asset left a building and triggered an event. A model was used for searching for a missing item in a room. The results showed that the system was able to produce two distances, one straight-line distance and the other the approximate sum distance travelled by the asset in 30-minute intervals. The RF model was able to find an asset in a room filled with different materials.

Prevailing propagation phenomena in certain areas play a vital role in deciding terrestrial wireless systems performance. Vertical refractivity profile below 1 km is a critical parameter for designing reliable systems; noting that there is a shortage of upper-air data worldwide. Anomalous phenomena may cause severe signal fading and interference beyond the horizon. The objectives of this thesis are to investigate dominant refractive conditions in the subtropical Arabian Gulf region, develop new approaches and empirical models for evaluating vertical refractivity profiles and relevant propagation parameters in the low troposphere, and to examine the impact of frequently experienced anomalous phenomena on terrestrial microwave links. Twenty-three years of meteorological measurements, from 1990 to 2013, are utilized using spatially separated surface stations and a single radiosonde in the United Arab Emirates (UAE). Profiles of sea level, surface and upper refractivity components are statistically analysed. Three major atmospheric layers; namely 65 m, 100 m and 1 km above the ground are studied to analyse relevant propagation parameters such as sub-refraction, super-refraction, anomalous propagation probability parameter β0 and point refractivity gradient not exceeded for 1% of time. The effective earth radius factor k is investigated using a new weighted averaged approach. In addition, the seasonal structure of atmospheric ducting is dimensioned within 350 m layer above ground. Finally, microwave measurement campaign is conducted using multiple radio links operating in UAE using various frequency bands. The link budget simulations are compared with the signal strength measurements. Fading scenarios are studied against the observed anomalous conditions and several recommendations are concluded.

En tapper är en person som rent fysiskt, med en stav, petar på en synskadad simmaren för att informera om vändning. Om arbetet som tapper kan bytas emot en teknisk lösning skulle detta ge simmaren mer frihet för träning. Målsättningen med projektet var att undersöka om det med hjälp av Blåtandssändare och mottagare, så som en mobiltelefon eller träningsklocka, är möjligt att fastställa en simmares positionering så pass noggrant att dessa kan användas för signalsystem för synskadade simmare vid vändningar. Projektet testade olika placeringar av sändare och fann att flera sändare i samverkan kan ge ett mer exakt och stabilt värde än en enstaka. Tester visade tydliga mönster i de registrerade värdena. Mönster i form av tydliga toppar vid närmanden av sändare. Detta leder till slutsatsen att ett blåtandsystem med flera sändare är fullt möjliga för att kunna känna om en simmare närmar sig. Men att sådana system förutsätter vidare tester och filtrering av mottagen signalstyrkeindikator (RSSI). Detta då signalstyrkan kraftigt försämras i vatten. Sändarnas placering vid bassängens ändar verkar ge bäst resultat men kan med fördel kombineras med ytterligare mjukvaru- eller hårdvarusensorer så som accelerator eller liknande. / A tapper is a person who physically prods a visually impaired swimmer with a stick to inform the latter about the time too turn. If a technical solution could be used instead of the tappers, this would give the swimmer more freedom when training.The goal of the project was to investigate whether, with the help of Bluetooth transmitters and receivers such as a mobile phones or training watches, it is possible to determine a swimmer's positioning so accurately that these can be used for signal systems for visually impaired swimmers when turning.The project tested different placements of transmitters and found that several transmitters in cooperation can give a more accurate and stable value than a single one. Tests showed clear patterns in the recorded values. Patterns in the form of clear peaks when a swimmer is approaching the transmitter. This leads to the conclusion that a Bluetooth system with several transmitters is entirely possible for swimmer detection. But that such a system requires further tests and filtering of Received Signal Strength Indicator (RSSI) as the signal strength is greatly degraded in water. Placing the transmitters at the ends of the pool seems to give the best results but can advantageously be combined with additional hardware or software sensors for example accelerometer.