Nowadays most of the communications systems are designed considering only to work under AWGN (Additive White Gaussian Noise). But the implementation of wireless systems in industrial facilities brings different kind of interference from machines or any other kind of electronic devices. Some of them are sources of randomly and high power noise, which commonly is known as impulsive noise. The objective in this thesis is to study the impact of the impulsive noise on a communication using QAM (Quadrature Amplitude Modulation) and PSK (Phase-Shift Keying) schemes, by observing the BER (Bit Error Rate) and the APD (Amplitude Probability Distribution). For that, it is developed a measurement method that will be used in a real industrial environment in future work.      The content of this thesis is divided in two parts. In the first part is made a program in MATLAB to simulate the communication through a noisy channel. Then is developed a measurement method which is tested in three different ways corresponding to 3 different outputs of an spectrum analyzer, namely, 20,4 MHz IF output, video output and IQ data output.      The relation of impulsive noise is presented in the second part with different statistical properties in the BER and the APD, in the setup with the best performance. At the end of the thesis a concluding section summarizes the results obtained during the work and some lines of future work in a real industrial environment with the developed method.

Due to the increase in volume and speed of data transmissions in recent years, the demand for high-speed satellite communication solutions has increased. This thesis investigates the possibility of making a receiver for satellite radio based on an Analog Devices ADC evaluation board. To do this, evaluation boards for each component were acquired and tested individually before connecting them. The system components include an I/Q demodulator, a local oscillator, and an ADC. Using these components a system design for the radio receiver has been proposed, and its performance analyzed. The SNR of the designed system was measured to26 dB. This performance was deemed to be sufficient for a signal using the BPSKmodulation scheme.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / As frequency allocation restrictions are tightening, and data rates are increasing, it is becoming necessary to incorporate higher order modulation techniques to make more efficient use of available spectrum. When used with Square Root Raised Cosine filtering, 8-ary Phase Shift Keyed modulation is a spectrally efficient technique that makes better use of today’s RF spectrum in comparison to standard formats. This paper will discuss 8-ary PSK modulation and its spectral efficiency with a SRRC filter, along with comparisons to BPSK, QPSK, and FSK.

The thesis deals with improving location determination when using time of flight of radio signals to determine the location of a radiator. The goal of this project is to enhance an existing wireless data access point to perform an accurate measurement of the time of arrival of a data signal from a transmitter, and to combine this information with information from additional wireless data access points to determine the location of the transmitter. There have been a number of earlier efforts in indoor location determination system using different technologies. Many of which used signal strength analysis and they have low tolerance to moving obstacles such as humans, which frequently are the most usual dynamic obstacles in indoors. In this thesis, the proposed solution utilizes time stamping and sample correlation to utilize properties of the signal waveform, which has not previously been examined by researchers other than the examiner and advisor. The main contribution of the project is a detailed analysis and design of a solution, as well as a comparison with other potential solutions. The main purpose of this solution is to increase the timing accuracy to below the duration of a single symbol. The wireless device that has been analyzed implements the IEEE 802.11b protocol. Several investigations have been done to determine the best way of extracting information from the 802.11b data frame and symbol sequence; here we utilize a correlator to determine the time of arrival of a specific sequence of symbols in a data frame. The time stamping of a stream of samples has been implemented in an Altera FPGA to get a deterministic computation time. Instead of decoding the incoming I&Q signals and mapping them to bits, the correlator is used to detect the unique sequence containing PSK encoded and Barker code spread scrambled ones , as this sequence always appears at the start of each data frame. The advantage of this approach is that using of samples of the waveform instead of bits gives a significant enhancement in timing resolution. The design documents of this work include detailed descriptions, simulations, and plots. A number of simulations have been done to show the timing accuracy and standard deviation, as well as comparisons with several different approaches. Several potential optimizations have also been discussed in the report. Simulation code for MATLAB and implementation code for the FPGA has been included in appendices in the end of this thesis. / Denna rapport beskriver ett examensarbete som utgår ifrån att förbättra noggrannhet av en lokaliseringsteknik som tillämpar flygtiden av radiosignal för att mäta positionen av utsändaren. Målet av detta arbete är att förstärka en befintlig trådlösdata accesspunkt för att utföra en noggrann mätning av signals anländning från sändaren, och kombinera denna information från ytterliga trådlösdata accesspunkter för att lokalisera sändaren. Det har varit ett antal utvecklingar med olika teknologier för att ta fram en lösning för inomhus lokaliseringssystem. Många av de förslag som har kommit fram tillämpa signalstyrka och har en dålig tolerans av rörande hinder så som människor, vilka är det vanligaste fallet inomhus. Denna rapport ger ett förlag att lösa detta problem med att tillämpa tidstämpel och sampelkorrelation för att utnyttja egenskaper av signalens vågform, ett förlag som inte har blivit undersökt mycket av andra forskare. Stor del av denna rapport består av detaljerad analys och lösningsdesign, plus en jämförelse med andra potentiella lösningar. Meningen med denna lösning är att öka noggrannhet till att felmarginal i tid ska ligga under en symboltid. Den trådlösa enhet som har analyserats implementerar IEEE 802.11b protokollen. Flera undersökningar har utförts för att bestämma det bästa sättet att extrahera information från 802.11b dataramer och symbolsekvenser. För att göra det har vi implementerat en korrelator för att bestämma anländningstid av specifika symbolsekvenser i en dataram. En Altera FPGA har använts för att tidstämpla inkommande sampel för att ge en deterministisk beräkningstid. Istället för att avkoda inkommande I&Q signaler och mappa dem till bitar, har vi valt att implementera korrelator så att den opererar direkt på PSK-modulerade och Barkerkod-spridda ettor, eftersom att det visar sig att denna sekvens alltid visar sig i början av varje dataram. Fördelen med denna lösning är att direktanvändning av sampel ger en signifikant ökning på tidsupplösning jämfört med bitar. Designdokumentet av detta examensarbete består av detaljerade beskrivningar, simuleringar och grafer. Ett antal simuleringar har utförts för att visa tidsnoggrannhet och medelfel, plus jämförelser mellan olkia lösningsförslag. Olika möjliga optimeringar har också diskuterats i rapporten. Simuleringskod för MATLAB och implementeringskod FPGA bifogas i appendix slutet av denna rapport.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The national telemetry ranges are being pushed to provide higher data rate telemetry services by users with increasingly complex test procedure for increasingly complex weapon systems. At the same time they are having trouble obtaining more spectrum in which to provide these higher rates because of the demand for spectrum in SHF range from various mobile/cellular Personal Communications Services (PCS) as well as congress’s desire to auction spectrum and to transfer as much spectrum as possible to commercial uses. In light of these pressures the industry is in need of a modulation standard that will out perform the existing PCM/FM standard. The motivation for the present review and analysis of the performance of various coded/uncoded modulation schemes arises from this issue. Comparison of the performance of these schemes will be utilized in the following work to find a suitable solution to the existing problem.

Nowadays the rapid developments of wireless communication technologies there are more and more ways to look into the RF measurements and designs in detail such as Universal Software Radio Peripheral(USRP) from LabVIEW, Advance Design System(ADS),etc.Moreover a lack of measurements what compared with different digital modulation schemes is becoming a problem. In this thesis by building the simulations of communication system in NI-USRP system and measuring the results then compare with the different PSK system in order to give a deeper insight of this new software of USRP from LabVIEW. and in the end analyze bit error rate varus signal to noise ratio from the PSK system. To get the characterizations of NI-USRP system the first step is to build multiple simulations such as FM receiver, PSK wireless communication systems. By performing the FM receiver is to analyze the quality of the receiving and baseband FM signal. And from the simulation of different PSK communications through the analysis of the performance of BPSK,QPSK,OQPSK and compared with bit error rate it could give an insight of characterization of NI-USRP system and in the end the conclusions give in which kind of prototype or simulation that suit the best of NI-USRP system.

[pt] A análise de desempenho de sistemas de comunicações nos quais um grande número de portadoras, de diferentes tipos e níveis de potência, acessam uma mesma não-linearidade, esbarra, inicialmente, na dificuldade de se determinar, com precisão e tempo de computação aceitável, a distribuição de potência do ruído de intermodulação gerado. O problema torna-se ainda mais complexo nos casos em que as portadoras têm envoltória variável no tempo, quando, além de se tornar mais difícil a determinação do espectro de intermodulção, há o aparecimento adicional da transferência de modulação das demais portadoras para a portadora desejada. Com o enfoque voltado para o desempenho de sistemas digitais, mostra-se que, utilizando-se determinados algoritmos e aproximações, o tratamento analítico torna-se factível. Com base na teoria apresentada, foi desenvolvido um programa de computador que permite avaliação de desempenho em situações bastante gerais. / [en] One of the difficulties arising in a theoretical performance evaluation of communication systems in which several carriers of various types are transmitted through a cammon nonlinear amplifier, is related to the problem of calculating, with good precision and within reasonable computer time, the power spectrum of the intermodulation noise generated at the output of the nonlinear device. The analysis becomes more complex when the carriers have time- varyng envelopes, since in such situations, besides the difficulty involved in determining the power and spectrum shape of the output signals and intermodulation products, an extra system impairment should be taken into account. Namely, the performance degradation due to modulation transfer from all the other carriers into the desired carrier. With focus on digital systems, it is shoun that, by using certain algorithms and approximations, theoretical performance analysis is feasible. Based on the results presented, a computer program was developed to evaluate performance in fairly general situations.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The most bandwidth-efficient communication methods are imperative to cope with the congested frequency bands. Pulse Shaping methods have excellent effects on narrowing bandwidth and increasing band utilization. The position of the baseband filters for the pulse shaping is crucial. Filters after the modulator will have non-constant envelope and before the modulator will have constant envelope. These two types have different effects on narrowing the bandwidth and producing bit errors. The constant envelope 8 PSK is used throughout the simulations and is compared with the non-constant envelope results. This work provides simulation results of spectrum analysis and measure of bit errors produced by pulse shaping in an AWGN channel.

Today, medical implants such as cardiac pacemakers, neurostimulators, hearing aids anddrug delivery systems are increasinglymore important and frequently used in the health caresystem. This type of devices have historically used inductive coupling as communicationmedium. Newdemands on accessibility and increased performance in technology drives newresearch toward using radio communications. The FCCMICS radio standard are specificallydevoted for implantable devices.Basically all published research on transmitters in this area are using frequency shift keying(FSK) modulation. The purpose of this thesis is to explore the viability of using phase shiftkeying (PSK) modulation in ultra low power transmitters and suggest suitable architectures.

Dispersed spectrum cognitive radio systems represent a promising approach to exploit the utilization of spectral resources to full extent. Therefore, the performance analysis of such systems is conducted in this research. The Average symbol error probability of dispersed spectrum cognitive radio systems is derived for two cases: where each channel realization experiences independent and dependent Nakagami-m fading, respectively. In addition, the derivation is extended to include the effects of modulation type and order by considering M-PSK and M-QAM modulation schemes. We then study the impacts of topology on the effective transport capacity performance of ad hoc dispersed spectrum cognitive radio systems where the nodes assume 3- dimensional (3D) configurations. We derive the effective transport capacity considering a cubic grid distribution. In addition, numerical results are presented to demonstrate the effects of topology on the effective transport capacity of ad hoc dispersed cognitive radio systems.