Digital treinsmission of information is finding an ever-increasing number of applications in the leind-mobile radio service. There is a possibility that in the long term, due to the increasing demand for mobile radio channels, their bandwidths will be reduced to 5kHz. A digital minimum shift keying (MSK) modulation scheme is proposed in this work for narrow band digital mobile radio transmission. The design and implementation of an MSK modulator and coherent and noncoherent demodulators are given. Their structure is highly flexible and can accommodate a wide range of medium digital transmission rates. The demodulators were tested for the transmission of 2.4kbit/sec in simulated typical land-mobile radio transmission conditions. The results of these tests favoured the use of the noncoherent demodulator for this type of application. Achieving spectrum efficiency in this proposed scheme relies on postmodulation filtering of the MSK signal. A polar loop VHF transmitter was tested for high efficiency linear power amplification of the MSK signal. It proved its validity for this type of application. A digital clock recovery circuit suitable for use in mobile radio conditions has also been built and tested. The principles of the circuit operation and its implementation are discussed.

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Time Difference Of Arrival (TDOA) based position tracking technique is one of the pinnacles of sports tracking technology. Using radio frequency com-munication, advanced filtering techniques and various computation methods, the position of a moving player in a virtually created sports arena can be iden-tified using MATLAB. It can also be related to player’s movement in real-time. For football in particular, this acts as a powerful tool for coaches to enhanceteam performance. Football clubs can use the player tracking data to boosttheir own team strengths and gain insight into their competing teams as well. This method helps to improve the success rate of Athletes and clubs by analyz-ing the results, which helps in crafting their tactical and strategic approach to game play. The algorithm can also be used to enhance the viewing experienceof audience in the stadium, as well as broadcast.In this thesis work, a typical football field scenario is assumed and an arrayof base stations (BS) are installed along perimeter of the field equidistantly.The player is attached with a radio transmitter which emits radio frequencythroughout the assigned game time. Using the concept of TDOA, the position estimates of the player are generated and the transmitter is tracked contin-uously by the BS. The position estimates are then fed to the Kalman filter, which filters and smoothens the position estimates of the player between the sample points considered. Different paths of the player as straight line, circu-lar, zig-zag paths in the field are animated and the positions of the player are tracked. Based on the error rate of the player’s estimated position, the perfor-mance of the Kalman filter is evaluated. The Kalman filter’s performance is analyzed by varying the number of sample points.

Large scale path loss modeling plays a fundamental role in designing both fixed and mobile radio systems. Predicting the radio coverage area of a system is not done in a standard manner. Wireless systems are expensive systems. Therefore, before setting up a system one has to choose a proper method depending on the channel environment, frequency band and the desired radio coverage range. Path loss prediction plays a crucial role in link budget analysis and in the cell coverage prediction of mobile radio systems. Especially in urban areas, increasing numbers of subscribers brings forth the need for more base stations and channels. To obtain high efficiency from the frequency reuse concept in modern cellular systems one has to eliminate the interference at the cell boundaries. Determining the cell size properly is done by using an accurate path loss prediction method. Starting from the radio propagation phenomena and basic path loss models this thesis aims at describing various accurate path loss prediction methods used both in rural and urban environments. The Walfisch-Bertoni and Hata models, which are both used for UHF propagation in urban areas, were chosen for a detailed comparison. The comparison shows that the Walfisch-Bertoni model, which involves more parameters, agrees with the Hata model for the overall path loss.

<p>Large scale path loss modeling plays a fundamental role in designing both fixed and mobile radio systems. Predicting the radio coverage area of a system is not done in a standard manner. Wireless systems are expensive systems. Therefore, before setting up a system one has to choose a proper method depending on the channel environment, frequency band and the desired radio coverage range. Path loss prediction plays a crucial role in link budget analysis and in the cell coverage prediction of mobile radio systems. Especially in urban areas, increasing numbers of subscribers brings forth the need for more base stations and channels. To obtain high efficiency from the frequency reuse concept in modern cellular systems one has to eliminate the interference at the cell boundaries. Determining the cell size properly is done by using an accurate path loss prediction method. Starting from the radio propagation phenomena and basic path loss models this thesis aims at describing various accurate path loss prediction methods used both in rural and urban environments. The Walfisch-Bertoni and Hata models, which are both used for UHF propagation in urban areas, were chosen for a detailed comparison. The comparison shows that the Walfisch-Bertoni model, which involves more parameters, agrees with the Hata model for the overall path loss.</p>

Les systèmes de localisations existants présentent des insuffisances au niveau desapplications en environnement indoor. Ces insuffisances se traduisent soit par la non-disponibilité des signaux (le GPS) dans ce type d’environnement, soit par leur manque de précision quand ils sont prévus à cet effet. Ces limites ont motivé la recherche de nouvelles techniques. Les transmissions Ultra-Large Bande (ULB) de par leur singularité en matière de précision et de faible puissance d’émission, s’avèrent être la meilleure réponse à la problématique ci-dessus. Nous avons donc choisi cette technique pour mettre au point un procédé de localisation endogène permettant d’assurer, avec précision, la continuité des services de localisation dans les environnements indoor. Ce procédé s’appuie sur la localisation en trois dimensions (3-D). Il utilise la technique temporelle de différenciation du temps d’arrivée (TDOA). Cette technique permet de mieux tirer profit de la bonne résolution temporelle de l’ULB et de pallier au problème de synchronisation entre l’émetteur et le récepteur. Deux techniques de transmission ULB ont été étudiées : la technique d’accès multiples par séquence directe (DS-CDMA) et la technique d’accès multiples par sauts temporels (TH-CDMA). Une autre étape importante de notre étude a été de développer un algorithme non-itératif de localisation en 3-D pour réduire le temps de calcul. En effet, l’utilisation d’un algorithme non-itératif permet d’optimiser les performances du système en termes de temps de calcul voire de coûts de consommation énergétique. Après l’étude théorique des différents blocs du système, le système a été tout d’abord simulé dans le canal Gaussien (AWGN) et les canaux IEEE.802.15.4a indoor. Il a été ensuite testé dans différents environnements réels de types laboratoires. Les résultats obtenus démontrent que l’utilisation des techniques de transmission basées sur la technologie radio impulsionnelle ULB permet d’obtenir un système de localisation en 3-D avec une précision centimétrique pour les applications indoor. / Existing positioning systems have deficiencies in applications indoor environment. These deficiencies result is the non-availability of signals (GPS) in this type of environment, either by their lack of precision when they are provided for this purpose. These limitations have led to research for novel techniques. Ultra-Wide Band (UWB) transmission techniques due to their uniqueness in terms of fine resolution and low power emission, prove to be the best answer to this problem. So we choose this technique to develop a process to ensure self location, with accuracy, continuity of location services in indoor environments. This method is based on the location in three dimensions (3-D). It uses the Time Difference Of Arrival (TDOA) technique. This technique allows to better take advantage of the high time resolution of the ULB and overcome the problem of synchronization between the transmitter and the receiver. Two UWB transmission techniques were studied: the Direct Sequence multiple access technique (DS-CDMA) and Time Hopping (TH-CDMA) multiple access technique. Another important step in our study was to develop a non-iterative positioning algorithm in 3-D to reduce the computation time. Indeed, using a non-iterative algorithm optimizes system performance in terms of computing time or cost of energy consumption. After the theoretical study of the system, the proposed positioning system was firstly simulated in Additive White Gaussian Noise (AWGN) channel and indoor IEEE.802.15.4a channels. It was then tested in various real environments types laboratories. The results obtained show that using UWB impulse radio technology transmission techniques allows to achieve a high accuracy 3-D location system in order of centimeter for applications in indoor environments.

Due to the increasing demand of broadband capability and reconfigurability for mobile applications, there is an enormous interest to develop appropriate analog receiver front-ends. In this respect, one promising candidate group is the Six-Port-based direct conversion receiver. The presented work focuses on the investigation of Six-Port-based mobile receiver front-ends with their specific systematical signal processing. Thereby, issues of spurious interfering signals which are generated within the down conversion process of such receivers are of special interest. Based on a comprehensive description of the analog signal processing within additive frequency conversion, a reason could be identified why existing Six-Port receivers have not found any practical application in mobile communication yet – the dynamic DC-offset. With this insight compensation techniques were developed to overcome the negative influences of the dynamic DC-offset. Furthermore, this work presents novel Six-Port-based receiver architectures which, on the one hand, keep the advantages of additive mixing systems like: low power consumption, broadband capability and simplicity of implementation especially for mm-wave transmissions. On the other hand, these novel architectures comprise compensation techniques such that systematically generated spurious signals are inherently compensated in the analog part of the receiver. Moreover, the influence of impairments of phase and amplitude within the IQ-branches of a receiver was investigated. The resulting, unwanted IQ-imbalance was shown to be a mixing method (multiplicative or additive) independent spurious effect. It is suggested to compensate for IQ-imbalance in the digital part of the receiver system. This can be realized with the use of adaptive algorithms. The comparison with conventional analog receiver architectures (especially homodyne receivers) with respect to the reception of today’s and future digitally modulated transmission signals indicate the proposed Six-Port-based receiver architectures to be suitable candidates to fulfill the difficult tasks of modern mobile communication.

Due to the increasing demand of broadband capability and reconfigurability for mobile applications, there is an enormous interest to develop appropriate analog receiver front-ends. In this respect, one promising candidate group is the Six-Port-based direct conversion receiver. The presented work focuses on the investigation of Six-Port-based mobile receiver front-ends with their specific systematical signal processing. Thereby, issues of spurious interfering signals which are generated within the down conversion process of such receivers are of special interest. Based on a comprehensive description of the analog signal processing within additive frequency conversion, a reason could be identified why existing Six-Port receivers have not found any practical application in mobile communication yet – the dynamic DC-offset. With this insight compensation techniques were developed to overcome the negative influences of the dynamic DC-offset. Furthermore, this work presents novel Six-Port-based receiver architectures which, on the one hand, keep the advantages of additive mixing systems like: low power consumption, broadband capability and simplicity of implementation especially for mm-wave transmissions. On the other hand, these novel architectures comprise compensation techniques such that systematically generated spurious signals are inherently compensated in the analog part of the receiver. Moreover, the influence of impairments of phase and amplitude within the IQ-branches of a receiver was investigated. The resulting, unwanted IQ-imbalance was shown to be a mixing method (multiplicative or additive) independent spurious effect. It is suggested to compensate for IQ-imbalance in the digital part of the receiver system. This can be realized with the use of adaptive algorithms. The comparison with conventional analog receiver architectures (especially homodyne receivers) with respect to the reception of today’s and future digitally modulated transmission signals indicate the proposed Six-Port-based receiver architectures to be suitable candidates to fulfill the difficult tasks of modern mobile communication.