ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper presents the issues related to the modeling and performance of the Radio Channel used in Telemetry. Because of the physical environment one expects stressed channel conditions due to multipath, shadowing, and high doppler shift caused by high speeds of up to mach 3. Prior work has created useful data and models for analysis of these radio channels. This paper will develop features of a channel simulator that will allow for evaluation of radio protocols for iNET. Substantial work has also been done to develop requirements for the iNET networked radio environment. This paper will map these requirements into technical features required for the radio link and consider how these will relate to the effects of the channels.

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Dynamic hardware and software schemes for trajectory based simulation of LEO satellite channel are presented and evaluated. The simulation models are based on the practical LEO satellite channels and change dynamically with the trajectory using the latitude and longitude of the LEO satellite as input. The hardware simulator is consisted of a trajectory based selective fade generator, a trajectory based Doppler shifter, trajectory based time shadowing simulator and a standard channel for addition of noise, ACI and CCI. A FQPSK modulated signal is passed through a trajectory based dynamic fade generator and the spectrum is distorted. Then the resulting signal is exposed to a trajectory based dynamic Doppler Shifter, simulating the passage of the satellite overhead. Then the proper AWGN, ACI or CCI is added to the signal. At the final stage the signal is passed through a trajectory based time Shadowing simulator. The software simulator is a dynamic real time simulator written in MatLab and its structure is similar to the hardware simulator.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Flight and weapons test ranges typically include multiple Telemetry Sites (TM Sites) that receive telemetry from platforms being flown on the range. Received telemetry is processed and forwarded by them to a Range Control Center (RCC) which is responsible for flight safety, and for delivering captured best source telemetry to those responsible for the platform being flown. When range equipment or operations are impaired in their ability to receive telemetry or process it correctly, expensive and/or one-of-a-kind platforms may have to be destroyed in flight to maintain safety margins, resulting in substantial monetary loss, valuable data loss, schedule disruption and potential safety concerns. Less severe telemetry disruptions can also result in missing or garbled telemetry data, negatively impacting platform test, analysis and design modification cycles. This paper provides a high level overview of a physics-compliant Range Test System (RTS) built upon Radio Frequency (RF) Channel Simulator technology. The system is useful in verifying range operation with most range equipment configured to function as in an actual mission. The system generates RF signals with appropriate RF link effects associated with range and range rate between the flight platform and multiple telemetry tracking stations. It also emulates flight and RF characteristics of the platform, to include signal parameters, antenna modeling, body shielding and accurate flight parameters. The system is useful for hardware, software, firmware and process testing, regression testing, and fault detection test, as well as range customer assurance, and range personnel training against nominal and worst-case conditions.

Underwater acoustic channel models have been studied in the context of communication and sonar applications. Acoustic propagation channel in an underwater environment exhibits multipath, time-variability and Doppler eects. In this thesis, multipath fading channel models, underwater physical properties and sound propagation characteristics are studied. An underwater channel model for sonar applications is proposed. In the proposed model, the physical characteristics of underwater environment are considered in a comprehensive manner. Experiments /simulations were carried out using real-life data. Model parameters are estimated for a specific location, scenario and physical conditions. The channel response is approximated by fitting the model output to the recorded data. The optimization and estimation are conducted in frequency domain using Mean Square Error criterion.

Η βελτιστοποίηση των συστημάτων επικοινωνίας πολλαπλών εισόδων-εξόδων (MIMO) απαιτεί τη δοκιμή τους υπό ρεαλιστικές συνθήκες και σε πολλά διαφορετικά περιβάλλοντα. Η δοκιμή απ’ ευθείας σε πραγματικά ασύρματα περιβάλλοντα δεν είναι αποδοτική μέθοδος, ειδικά κατά τα στάδια της σχεδίασης και του ελέγχου σωστής λειτουργίας, καθώς το κανάλι είναι πολύ ευαίσθητο, μη ελέγξιμο και μη αιτιατό. Επιπροσθέτως, η δοκιμή σε πραγματικά κανάλια δεν είναι πρακτική μέθοδος όταν χρειάζεται να δοκιμάσουμε πολλά διαφορετικά περιβάλλοντα ή να συμπεριληφθεί η κίνηση μέσα στις δοκιμές. Η δημιουργία ρεαλιστικών μοντέλων για κανάλια, χρησιμοποιώντας εργαλεία λογισμικού (Software) είναι μια δεύτερη επιλογή η οποία όμως δεν παράγει αποτελέσματα σε πραγματικό χρόνο και είναι επιπρόσθετα αρκετά χρονοβόρα. Ο λόγος είναι ότι αφού παραχθούν οι συντελεστές του καναλιού στο λογισμικό, η συνέλιξη των συντελεστών αυτών που συνιστούν την κρουστική απόκριση του καναλιού με τα μεταδιδόμενα σήματα είναι μια σχετικά αργή διαδικασία που θέτει φραγμούς στην εξομοίωση πραγματικού χρόνου. Σε κάποια συστήματα δοκιμών βασισμένα σε λογισμικό, τα διαμορφωμένα δεδομένα και τα διαλείπτοντα σήματα συντίθεται ώστε να δημιουργήσουν μιγαδικές (I/Q) κυματομορφές οι οποίες μεταφορτώνονται στη μνήμη μιας γεννήτριας αυθαίρετων κυματομορφών για να παραχθούν από τη γεννήτρια ραδιοκυμάτων. Υπάρχουν αρκετά εργαλεία λογισμικού που μπορούν να επιταχύνουν τη διαδικασία δημιουργίας κυματομορφών με διαλείψεις, όπως για παράδειγμα το εργαλείο MatlabΤΜ της εταιρείας MathWorks, αλλά αυτά περιορίζονται στα παραδοσιακά μοντέλα διαλείψεων. Ακόμα οι γεννήτριες αυθαίρετων κυματομορφών διαθέτουν περιορισμένη μνήμη, με αποτέλεσμα οι παραγόμενες κυματομορφές να είναι αρκετά μικρές και να επαναλαμβάνονται απλώς στο χρόνο. Για όλους αυτούς τους λόγους χρειάζεται να επιστρατεύσουμε ειδικού σκοπού υλικό το οποίο εξομοιώνει ρεαλιστικά κανάλια πολλαπλών εισόδων-εξόδων ώστε να δώσουμε μια λύση στις απαιτητικές αυτές συνθήκες εξομοίωσης. Στην παρούσα διπλωματική σχεδιάσαμε έναν προσομοιωτή καναλιών για κανάλια βασικής ζώνης πολλαπλών εισόδων πολλαπλών εξόδων (baseband MIMO), σε αρχιτεκτονική υλικού και συγκεκριμένα σε συστοιχίες προγραμματιζόμενων πυλών (FPGA). Ο προσομοιωτής αυτός μπορεί να χρησιμοποιηθεί για την πιστοποίηση της λειτουργίας μιας σειράς επεξεργαστών για σύγχρονα και επόμενης γενιάς τηλεπικοινωνιακά συστήματα. / Optimization of multiple input multiple output (MIMO) communication systems, requires testing under realistic conditions and various channel environments. Direct tests on real-world channel environments, is not an efficient method since the channel is very sensitive, not controllable and non–causal. Moreover, testing in a real channel is not a practical method when various different channels need to be tested or mobility to be included in the tests. A second option is to create realistic channel models, using software tools but this does not produce real time results and can also be prohibitively time-consuming. The reason for this, is that after creating the channel coefficients in software that form the channel’s impulse response, the convolution of these coefficients with the transmitted signals is a relatively slow process that hinders real-time simulation. In some software-based test systems the modulated data and fading signals are used to create complex (I/Q) waveforms that are downloaded into the memory of an arbitrary waveform generator in order to be generated by the RF signal generator. Many software tools exist, that can accelerate the process of fading waveform creation, such as MathWorks’ MatlabΤΜ but these tools are limited to traditional fading models. Moreover the arbitrary waveform generators consist of limited memory resulting in short waveforms that simply repeat over time. For these reasons, a requirement for specialized instrumentation arises, one that can emulate realistic multiple input-multiple output channels, in order to provide an efficient solution to these demanding simulation conditions. In the context of the current thesis, we design a baseband multiple input-multiple output (MIMO) emulator into hardware, specifically into Field Programmable Gate Array (FPGA). This particular hardware component is suitable for the functional verification of a variety of baseband processors for current and next generation telecom equipment.

<div>Millimeter-wave (mmWave) bands have become the most promising candidate for enlarging the usable radio spectrum in future wireless networks such as 5G. Since frequent and location-specific blockages are expected for mmWaves, the challenge is understanding the propagation characteristics of mmWave signals and accordingly predicting the channel state information. This research direction has garnered great attention worldwide from industry, academia, and government. However, the majority of current research on mmWave communications has focused on urban areas with high population densities, with very few measurement campaigns in suburban and rural environments. These environments are extremely important for future wireless applications in areas including residential welfare, digital agriculture, and transportation. To fill in this research gap, we developed broadband mmWave channel sounding systems and carried out intensive measurement campaigns at 28 GHz, covering clear line-of-sight as well as non-line-of-sight scenarios over buildings and foliage clutters, to fully characterize the mmWave propagation in suburban and rural environments.</div><div><br></div><div>Moreover, the accuracy provided by traditional statistical models is insufficient for next-generation wireless networks with higher-frequency carriers, because they are unable to predict abrupt channel changes caused by site-specific blockages. To overcome this issue, we explored the possibility of utilizing site-specific geographic features such as buildings and trees in improving mmWave propagation models. A new channel modeling methodology highlighting site-specific parameter evaluation based on easily obtainable data sources (e.g., LiDAR) was proposed for accurate, fast, and automated channel state predictions. Accordingly, an overall root mean square error (RMSE) improvement of 11.79 dB was achieved in a one-building blockage scenario and a regional RMSE improvement of over 20 dB was observed in a coniferous forest. This approach also enables channel simulations for large-scale system performance evaluation, demonstrating a powerful and promising approach for planning and tuning future wide-area wireless networks. The simulation results showed that network densification alone is not enough for closing the digital gap, especially with mmWaves because of the impractical number of required towers. They also backed up supplementary solutions including private data relays, e.g., via drones and portable towers.</div>

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / RF Communication (COMMS) systems where receivers and transmitters are in motion must be proven rigorously over an array of natural RF link perturbations such as Carrier Doppler shift, Signal Doppler shift, delay, path loss and noise. These perturbations play significant roles in COMMS systems involving satellites, aircraft, UAVs, missiles, targets and ground stations. In these applications, COMMS system devices must also be tested against increasingly sophisticated intentional and unintentional interference, which must result in negligible impact on quality of service. Field testing and use of traditional test and measurement equipment will need to be substantially augmented with physics-compliant channel emulation equipment that broadens the scope, depth and coverage of such tests, while decreasing R&D and test costs and driving in quality. This paper describes dynamic link emulation driven by advanced antenna and motion modeling, detailed propagation models and link budget methods for realistic, nominal and worst-case hardware-in-the-loop test and verification.

Several emerging wireless applications require direct transmission between mobile terminals. Examples of these applications are mobile ad-hoc wireless networks, intelligent transportation systems, relay-based cellular networks, and future combat systems. Development of these mobile-to-mobile (M-to-M) systems depends on a good characterization of channel propagation. Another important consideration in modern communication systems is the use of multipath propagation to improve reliability and capacity of wireless systems. This is achieved by employing multiple antennas in multiple-input multiple-output (MIMO) systems and using techniques such as transmit and receive diversity. Considering the demand for high-speed wireless services, MIMO M-to-M systems are the leading candidates for future communication systems. To enable the successful design of MIMO M-to-M systems, our research focuses on modeling of MIMO M-to-M multipath fading channels and on diversity techniques for MIMO systems. Specifically, we propose two-dimensional (2-D) and three-dimensional (3-D) MIMO M-to-M statistical channel models that encompass narrowband and wideband MIMO channel scenarios for macro- and micro-cell environments. Furthermore, we validate the new models against measured data and find very close agreement between them. Using our 3-D models, we also investigate different antenna array configurations and their effect on the capacity of MIMO M-to-M systems. Contrary to common assumptions, we have found that there is no significant loss of capacity if the antenna array is tilted from the horizontal plane. Finally, we propose the design criteria for space-time coded continuous phase modulated systems. Our work would provide other researchers the tools needed to design and test future MIMO M-to-M communication systems.

[ES] Las redes inalámbricas interiores son una parte integral de las comunicaciones actuales. Debido a la alta demanda de confiabilidad y la enorme densidad de redes interiores, algunas de ellas están migrando hacia las frecuencias de onda milimétrica (mmW), donde están disponibles mayor ancho de banda y rendimiento. Diseñar la red para la banda mmW ofrece soluciones a algunos problemas presentes en frecuencias m 'as bajas pero también plantea nuevos desafíos. Esta Tesis se centra en particular en casos de uso de conferencias en entornos grandes. La principal funcionalidad de la red de conferencias es realizar conferencias. Principalmente, esto significa transmitir señales de audio desde los participantes y fuentes de audio a otros participantes. Por lo tanto, se presenta el conjunto de requisitos para el diseño y despliegue de la red resultantes de los estándares de la conferencia, tipos de datos, estructura de los datos transmitidos, propagación en ambientes interiores y fenómenos físicos relacionados con la longitud de onda. Las soluciones de conferencias inalámbricas existentes se proporcionan en frecuencias Wi-Fi, es decir, 2,4 GHz y 5 GHz. Sin embargo, su objetivo no es conectar a los participantes de la conferencia a Internet, sino crear una red que cumpla con los requisitos de la conferencia basada en la funcionalidad proporcionada en la familia de estándares 802.11. La enmienda 802.11ay se proporciona para la comunicación en la banda de frecuencia de 60 GHz. Para permitir una fácil transición de las redes de conferencias inalámbricas hacia mmW, se estudia la enmienda 802.11ay y el canal de radio de 60 GHz. Se considera que el estándar es inadecuado para el tipo y la cantidad de datos enviados en las redes de conferencias inalámbricas. Está diseñado para trabajar con grandes cantidades de datos, mientras que los datos principales en las redes de conferencias son audio en tiempo real. Enviar tramas de datos con esa poca información introduce una sobrecarga significativa debido a los datos del pre 'ambulo en PPDU. Sin embargo, se considera que algunas de sus características merecen una mayor exploración. Al estudiar el caso de uso de la conferencia, es importante centrarse en las configuraciones dedicadas a las conferencias, es decir, la influencia de las propiedades de los materiales interiores, la forma y el tamaño del entorno, y el tipo y ubicación de la antena en la propagación. Para el canal de radio de 60 GHz se estudia el efecto multitrayecto, lo que lleva a la creación del modelo de predicción RMS DS. Además, se muestra que la directividad en esta banda proporciona una gran ventaja si se utiliza la transmisión LoS o si el reflector conocido ayuda a dirigir el haz en la dirección de receptor (RX). Además, esta Tesis también se centra en frecuencias distintas a 60 GHz, precisamente 27 GHz y 28 GHz, las frecuencias introducidas en el Rango de Frecuencia 2 (FR2) 5G NR. Para esta Tesis se realizaron varias campañas de medición en diferentes ambientes, como el auditorio, el aula grande, la sala de reuniones y la sala de seminarios. Los resultados resaltan la importancia de conocer el entorno para optimizar el despliegue de la red. El ray tracing (RT) se utiliza para profundizar la comprensión del comportamiento de los canales de radio medidos. Se identifica el origen de los componentes de trayectorias múltiples y los objetos que son reflectores de mayor impacto. Además, las simulaciones de entornos disponibles se realizan para frecuencias, configuraciones de antenas y configuraciones de mobiliario distintas a las de las mediciones realizadas. Se midieron e introdujeron en el simulador RT los valores de las pérdidas de transmisión y reflexión introducidas por objetos presentes en entornos grandes en frecuencias de 26-40 GHz y 55-65 GHz para permitir resultados m 'as precisos de las simulaciones. La comparación entre mediciones y simulaciones muestra la utilidad de las simulaciones RT en el análisis de canales de radio. / [CA] Les xarxes sense fil d'interior són una part integral de les comunicacions actuals. A causa de l'alta demanda de fiabilitat i la gran densitat de xarxes interiors, algunes d'elles migren cap a les freqüències de les ones mil·límetres (mmW), on hi ha una amplada de banda i un rendiment més grans disponibles. Dissenyar la xarxa per a la banda mmW ofereix solucions a alguns problemes presents en freqüències més baixes però també planteja nous reptes. Aquesta tesi se centra especialment en casos d'ús de conferències en entorns grans. La principal funcionalitat de la xarxa de conferències és la realització de conferències. Principalment, això significa transmetre senyals d'àudio dels participants i fonts d'àudio a altres participants. Per tant, es presenta el conjunt de requisits per al disseny i desplegament de la xarxa resultant dels estàndards de conferència, els tipus de dades, l'estructura de les dades transmeses, la propagació en entorns interiors i els fenòmens físics relacionats amb la longitud d'ona. Les solucions de conferències sense fil existents es proporcionen en freqüències Wi-Fi, és a dir, 2,4 GHz i 5 GHz. Tanmateix, no pretenen connectar els participants de la conferència a Internet, sinó crear una xarxa que compleixi els requisits de la conferència basada en la funcionalitat proporcionada a la família d'estàndards 802.11. L'esmena 802.11ay es proporciona per a la comunicació a la banda de freqüència de 60 GHz. Per permetre una fàcil transició de les xarxes de conferències sense fil cap al mmW, s'estudia l'esmena 802.11ay i el canal de ràdio de 60 GHz. Es considera que l'estàndard és inadequat per al tipus i la quantitat de dades enviades a les xarxes de conferències sense fil. Està dissenyat per treballar amb grans quantitats de dades, mentre que les dades principals de les xarxes de conferències són àudio en temps real. L'enviament de trames de dades amb aquesta poca informació introdueix una sobrecàrrega important a causa de les dades del preàmbul a PPDU. No obstant això, es considera que algunes de les seves característiques mereixen una exploració més detallada. Mentre s'estudia el cas d'ús de la conferència, és important centrar-se en les configuracions dedicades a les conferències, és a dir, la influència de les propietats dels materials interiors, la forma i la mida de l'entorn, i el tipus i col·locació d'antena en la propagació. Per al canal de ràdio de 60 GHz, s'estudia l'efecte multicamí, que condueix a la creació del model de predicció RMS DS. A més, es demostra que la directivitat en aquesta banda dóna un gran avantatge si s'utilitza la transmissió LoS o si el reflector conegut ajuda a dirigir el feix en la direcció de receptor (RX). A més, aquesta Tesi també se centra en freqüències diferents de 60 GHz, precisament 27 GHz i 28 GHz, les freqüències introduïdes en el rang de freqüències 2 (FR2) 5G NR. Per a aquesta Tesi s'han realitzat diverses campanyes de mesura en diferents entorns, com ara l'auditori, l'aula gran, la sala de reunions i la sala de seminaris. Els resultats posen de manifest la importància de conèixer l'entorn per tal d'optimitzar el desplegament de la xarxa. El ray tracing (RT) s'utilitza per aprofundir en la comprensió del comportament dels canals de ràdio mesurats. S'identifica l'origen dels components multipath i els objectes que són reflectors més impactants. A més, es realitzen simulacions dels entorns disponibles per a freqüències, configuracions d'antenes i configuracions de mobles diferents de les de les mesures realitzades. Es van mesurar els valors de les pèrdues de transmissió i reflexió introduïdes per objectes presents en entorns grans en freqüències de 26-40 GHz i 55-65 GHz i es van introduir al simulador RT per permetre els resultats més precisos de les simulacions. La comparació entre mesures i simulacions mostra la utilitat de les simulacions RT en l'anàlisi de canals de ràdio. / [EN] Indoor wireless networks are an integral part of today's communications. Due to the high demand for reliability and the huge density of indoor networks, some of them are migrating towards the Millimeter Wave (mmW) frequencies, where larger bandwidth and throughput are available. Designing the network for the mmW band offers solutions to some problems present in lower frequencies but also poses new challenges. This Thesis focuses in particular on conference use cases in large environments. The main functionality of the conference network is to conduct conferences. Primarily, this means transmitting audio signals from participants and audio sources to other participants. Therefore, the set of requirements for the network design and deployment resulting from conference standards, data types, structure of transmitted data, propagation in indoor environments, and physical phenomena related to the wavelength are presented. Existing wireless conference solutions are provided in Wi-Fi frequencies, that is 2.4 GHz and 5 GHz. However, they do not aim to connect conference participants to the Internet but to create a network fulfilling the conference requirements based on the functionality provided in 802.11 standards family. The 802.11ay amendment is provided for communication in the 60 GHz frequency band. To allow an easy transition of wireless conference networks towards the mmW, the 802.11ay amendment and the 60 GHz radio channel are studied. The standard is found to be inadequate for the type and amount of data sent in the wireless conference networks. It is designed to work with large amounts of data, whereas the primary data in conference networks is real-time audio. Sending data frames with that little information introduces significant overhead due to the preamble data in Physical Protocol Data Unit (PPDU). Nevertheless, some of its features are considered worth further exploration. While studying the conference use case, it is important to focus on setups dedicated to the conferences, that is, the influence of indoor materials properties, the environment's shape and size, and antenna type and placement on the propagation. For the 60 GHz radio channel, the multipath effect is studied, which leads to the creation of the Root Mean Square Delay Spread (RMS DS) prediction model. Moreover, it is shown that directivity in this band gives a great advantage if the Line of Sight (LoS) transmission is used or the known reflector helps to steer the beam into the direction of the receiver. Furthermore, this Thesis also focuses on frequencies other than 60 GHz, precisely 27 GHz and 28 GHz, the frequencies introduced in Frequency Range 2 (FR2) Fifth Generation (5G) New Radio (NR). Several measurement campaigns were performed for this Thesis in different environments, such as the auditory, the large classroom, the meeting room, and the seminar room. The results highlight the importance of knowing the environment in order to optimize network deployment. The Ray Tracing (RT) is used to deepen the understanding of the measured radio channels' behaviour. The origin of multipath components and the objects that are most impactful reflectors are identified. Moreover, the simulations of available environments are performed for frequencies, antenna setups, and furniture configurations other than those in performed measurements. Values of transmission and reflection losses introduced by objects present in large environments in frequencies 26-40 GHz and 55-65 GHz were measured and introduced into the RT simulator to allow the most precise results of simulations. Comparison between measurements and simulations shows the usefulness of RT simulations in radio channel analysis. / This thesis was partly founded by the H2020 Marie Sklodowska-Curie Actions Program within Project Grant No. 766231 WAVECOMBE - ITN - 2017. Measurement campaigns in Gdansk University of Technology were partially funded by the COST Action CA20120, ”Intelligence-Enabling Radio Commu- nications for Seamless Inclusive Interactions” (INTERACT) under the Short Term Scientific Mission No. CA20120-2146922e. / Drozdowska, MK. (2024). Intelligent Design of mmWave Conference Networks in Built Environments [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/211182