Modern telecommunication systems and standards are mainly dependent on the availability of digital signal processing capabilities of appropriate hardware components. Two main categories can be distinguished in the development of digital signal processing units. On the one hand a number of general purpose digital signal processors are available on the market, which can be programmed through programming languages like C or C++ or - for higher performance purpose - directly in assembly code. The advantage of such devices is the ability of high flexibility and short time to market since there is no further hardware development, on the integrated circuit level, required. On the other hand hardware components are specifically developed for signal processing tasks, which are mainly application specific integrated circuits (ASIC). They are usually only programmable to a certain degree, always considering the area of application, i.e. wireless telecommunication systems. Although they do not offer the flexibility of general purpose digital signal processors, they offer the big advantage of less required hardware (measured as chip area or die size), lower power consumption and higher speeds. Usually hybrids are found on the market, which combine freely programmable Digital Signal Processor (DSP) with very specific hardware modules to support the specific application needs. This thesis describes the development of a Wireless Telecommunication System, describing the relevant development methodologies, regarding aspects of hardware and software split and actual implementations of components in hardware as well as in software. This is done specifically for the example of a wideband code division multiple access (WCDMA) wireless mobile system. The actual state of the art is described in detail, according to the relevant literature in the area of WCDMA systems. Programmable hardware is presented, which is covered through a portfolio of patents. The purpose and the application of each patent are described in detail as well as the area of application. Finally a classification of each patent is given, which aims to give an objective measure about the value of a patent. The presented patents show a significant contribution to knowledge enabling the development of low power mobile wireless telecommunication systems.

Mobile communication systems have continued to evolve beyond the currently deployed Third Generation (3G) systems with the main goal of providing higher capacity. Systems beyond 3G are expected to cater for a wide variety of services such as speech, data, image transmission, video, as well as multimedia services consisting of a combination of these. With the air interface being the bottleneck in mobile networks, recent enhancing technologies such as the High Speed Downlink Packet Access (HSDPA), incorporate major changes to the radio access segment of 3G Universal Mobile Telecommunications System (UMTS). HSDPA introduces new features such as fast link adaptation mechanisms, fast packet scheduling, and physical layer retransmissions in the base stations, necessitating buffering of data at the air interface which presents a bottleneck to end-to-end communication. Hence, in order to provide end-to-end Quality of Service (QoS) guarantees to multimedia services in wireless networks such as HSDPA, efficient buffer management schemes are required at the air interface. The main objective of this thesis is to propose and evaluate solutions that will address the QoS optimization of multimedia traffic at the radio link interface of HSDPA systems. In the thesis, a novel queuing system known as the Time-Space Priority (TSP) scheme is proposed for multimedia traffic QoS control. TSP provides customized preferential treatment to the constituent flows in the multimedia traffic to suit their diverse QoS requirements. With TSP queuing, the real-time component of the multimedia traffic, being delay sensitive and loss tolerant, is given transmission priority; while the non-real-time component, being loss sensitive and delay tolerant, enjoys space priority. Hence, based on the TSP queuing paradigm, new buffer managementalgorithms are designed for joint QoS control of the diverse components in a multimedia session of the same HSDPA user. In the thesis, a TSP based buffer management algorithm known as the Enhanced Time Space Priority (E-TSP) is proposed for HSDPA. E-TSP incorporates flow control mechanisms to mitigate congestion in the air interface buffer of a user with multimedia session comprising real-time and non-real-time flows. Thus, E-TSP is designed to provide efficient network and radio resource utilization to improve end-to-end multimedia traffic performance. In order to allow real-time optimization of the QoS control between the real-time and non-real-time flows of the HSDPA multimedia session, another TSP based buffer management algorithm known as the Dynamic Time Space Priority (D-TSP) is proposed. D-TSP incorporates dynamic priority switching between the real-time and non-real-time flows. D-TSP is designed to allow optimum QoS trade-off between the flows whilst still guaranteeing the stringent real-time component’s QoS requirements. The thesis presents results of extensive performance studies undertaken via analytical modelling and dynamic network-level HSDPA simulations demonstrating the effectiveness of the proposed TSP queuing system and the TSP based buffer management schemes.

This master thesis is a part of digitization project at NIBE AB, Markaryd, Sweden.Nowadays, the demand for digitization is increasing. One of the main goals ofdigitization is to build smart houses and industries to offer better lifestyles.NIBE is a company which produces heat pumps, water heaters, district waterheaters, digital stoves and etc. NIBE AB is planning to launch their new products witha communication module which helps users to control NIBE AB’s products remotelythrough their personal devices such as mobile phones, remote control devices and etc.The main objective of this thesis project is to improve these communicationmodules by improving their antenna with better design or replacing them with otherkinds of antennas for efficient communication and also accordingly design impedancematching networks for the system.This work presents the integrated results of an antenna for NIBE AB, tuned tocover 2.45 GHz ISM band which will implemented on a communication module. Wedesigned and simulated four types of different Printed Circuit Board (PCB) antennasand we got the better simulation results of Gain, Reflection Coefficient, VSWR andBand Width from these designs.Also, we used different types of substrates in the simulation to get goodresults and design the impedance matching networks accordingly. If we compare theresults with the current monopole antenna and its parameters, we have goodcharacteristic results in most of the aspects.

When transmitting data from an aircraft being prepared at the apron (the area in front of the hangar) telemetry data is transmitted to ground personnel. The transmitted data is subject to severe distortion due to multipath propagation created by the surroundings, resulting in erroneous detection. By equalizing the signal using the Constant Modulus Algorithm a significant increase in detection performance has been observed, both in simulations and tests on collected data. The most sufficient parameters were chosen after testing a set of different parameter combinations on simulations with single delays. These parameters were then used to equalize simulated multipath as well as collected data. The results show that short delays with low power can be resolved without any equalizer. Longer delays with relatively low power can be resolved using the proposed equalizer but long delays with high power cannot be resolved by the equalizer at all. The thesis shows that it is worth investigating implementation of the equalizer.

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Advances in communication technologies continue to increase information sharing among the people.~Short-range wireless networking technologies such as Bluetooth or ZigBee, which are mainly used for data transfer over short range, will, however, suffer from network congestion, high power consumption and security issues in the future. The body-coupled communication (BCC), a futuristic short-range wireless technology, uses the human body as a transmission medium. In BBC channel, a small electric field is induced onto the human body which enables the propagation of a signal between communication devices that are in the proximity or direct contact with the human body. The direct baseband transmission and simple architecture make BCC an attractive candidate for a future short-range wireless communication technology in particular applications such as body area network. The main focus of this thesis is on the design and implementation of digital baseband transmitter and receiver for the body-coupled communication. The physical layer (PHY) implementation of the digital baseband transmitter and receiver is inspired from the IEEE 802.3 Ethernet transmission protocol. The digital design is implemented at RTL level using hardware description language (VHDL). The functionality of the digital baseband transmitter and receiver is demonstrated by developing data transfer application layers.

As increased demand of cloud computing leads to increased electricity costs for cloud providers, there is an incentive to investigate in new methods to lower electricity costs in data centers. Electricity price markets suffer from sudden price spikes as well as irregularities between different geographical electricity markets. This thesis investigates in whether it is possible to leverage these volatilities and irregularities between different electricity price markets, to offload or move storage in order to reduce electricity price costs for data storage. By forecasting four different electricity price markets it was possible to predict sudden price spikes and leverage these forecasts in a simple optimization model to offload storage of data in data centers and successfully reduce electricity costs for data storage.

D.Ing. / This thesis sets out to propose and analyze a cellular Direct Sequence Spread Spectrum Multiple Access (DSjSSMA) system for the Indoor Wireless Communication (IWC) Nakagami fading channel. The up- and downlink of the system implement Differential Phase Shift Keying (DPSK) and Coherent Phase Shift Keying (CPSK) as modulation schemes respectively, and are analyzed using Maximum Entropy (MaxEnt) principles due to its reliability and accuracy. As a means to enhance system capacity and performance, different forms of diversity are investigated; for the up- and downlink, respectively, RAKE reception and Maximum Ratio Combining (MRC) diversity together with Forward Error Control (FEC) coding are assumed. Further, the validity of the Gaussian Assumption (GA) is quantified and investigated under fading and non-fading conditions by calculating the missing information, using Minimum Relative Entropy (MRE) principles between the Inter- User Interference (IUI) distribution and a Gaussian distribution of equal variance.

M.Ing. / In general, error control coding is absolutely necessary for reliable data transmission. However, the performance of error control codes depends on the statistical structure of the error process on the communication channel. The mobile radio channel, which has been investigated, is subject to path loss effects, a variety of noise effects and interferences and various types of scattering and multipath fading. All these effects contribute to the error processes on the radio channel when transmitting data over it. Any meaningful analytical description of the error process in terms of the characteristics of the individual physical causes of errors are difficult to undertake. Consequently, alternative ways of modelling real communication. channels are being presented. It is more convenient to include the above mentioned perturbations in a discrete inner communication channel consisting of the modem, radio equipment and the mobile radio medium, which are then modelled with a discrete partitioned Markov chain. The partitioned Markov chain inner channel models also give a more accurate description of a real communication channel than does a binary symmetric channel model. However, in order to model a communication channel, the complete statistical structure of the bit error sequence on the channel must be known. In the first instance the memory effective recording of the error sequence of discrete inner communications channels has been considered. This has led to an implementation, where a portable recording system has been developed for mobile .radio channels or any other communication channel with a data rate of up to 4800 bits per second. Programs have been developed to determine all the important statistical distributions which are necessary to be able to model the channel. A channel modelling system has been developed, which fits a channel model to the real channel and then determines the important statistical distributions of the channel model to enable comparison with the real channel. The channel modelling system is versatile and can be used with any future communication system. A number of different mobile VHF and UHF inner channels have been investigated experimentally and the associated discrete models have been developed. In addition to the above mentioned discrete inner communications channels, some "outer channels" have been developed. The "outer channels" comprise of an inner channel and the block error detection, correction and misdetection events, associated with the code words of an error control system. It has been shown that the underlying statistical structure of these events on a discrete renewal inner channel can be represented with outer channel models, i.e. simple partitioned Markov processes, similar to the inner channel models. Analytical procedures to determine the parameters of these outer channel models are being presented. The inner channel parameters and the characteristics of the error control event have been used to develop the outer channel models, i.e. the simple partitioned Markov chains, representing the underlying statistical structure of the block error detection, decoding error in error correction and misdetection (undetected error) events of a block code on the discrete renewal inner channel. Finally it is shown that these outer channel models can be used to evaluate error control codes and systems. Forward-error control and automatic-repeat-request systems have been evaluated and compared with each other.

Kommunikation är viktigt i alla arbetssituationer som involverar mer än en individ. Vi tror teknologin hos tillverkarna av aktiva hörselkåpor har kommit ikapp med kraven som ställs på dom men helt enkelt glömts bort av industrin. Syftet med det här experimentet är att testa om de aktiva hörselkåporna kan skilja på allt bakgrundsljud som finns i ett maskinrum och samtalsljud från en annan människa. Experiementet tar plats först i ett maskinrum ombord på Calmare Nyckel för att mäta upp referensvärden sedan därefter i maskinsimulatorn. Testerna ombord på Calmare Nyckel och i simulatorn fick liknande resultat vilket bevisar att det inte spelar någon roll om ljudet kommer från en maskin eller en högtalare. Resultatet av experimentet visade att det inte spelar roll om ljudet kommer från en högtalare eller en maskin eftersom frekvensen vi pratar på var starkt representerad i båda fallen. Alla deltagare i experiment sa att dom inte kände någon märkbar förbättring av förståelsen genom medhörningen. Om något var hörselkåporna bara tyngre och större att ha på huvudet vilket uppfattas något negativt.