Economically sustainable public security and emergency network exploiting a broadband communications satellite

The research contributes to work in Rapid Deployment of a National Public Security and Emergency Communications Network using Communication Satellite Broadband. Although studies in Public Security Communication networks have examined the use of communications satellite as an integral part of the Communication Infrastructure, there has not been an in-depth design analysis of an optimized regional broadband-based communication satellite in relation to the envisaged service coverage area, with little or no terrestrial last-mile telecommunications infrastructure for delivery of satellite solutions, applications and services. As such, the research provides a case study of a Nigerian Public Safety Security Communications Pilot project deployed in regions of the African continent with inadequate terrestrial last mile infrastructure and thus requiring a robust regional Communications Satellite complemented with variants of terrestrial wireless technologies to bridge the digital hiatus as a short and medium term measure apart from other strategic needs. The research not only addresses the pivotal role of a secured integrated communications Public safety network for security agencies and emergency service organizations with its potential to foster efficient information symmetry amongst their operations including during emergency and crisis management in a timely manner but demonstrates a working model of how analogue spectrum meant for Push-to-Talk (PTT) services can be re-farmed and digitalized as a “dedicated” broadband-based public communications system. The network’s sustainability can be secured by using excess capacity for the strategic commercial telecommunication needs of the state and its citizens. Utilization of scarce spectrum has been deployed for Nigeria’s Cashless policy pilot project for financial and digital inclusion. This effectively drives the universal access goals, without exclusivity, in a continent, which still remains the least wired in the world

Architecture and algorithms for the implementation of digital wireless receivers in FPGA and ASIC: ISDB-T and DVB-S2 cases

[EN] The first generation of Terrestrial Digital Television(DTV) has been in service for over a decade. In 2013, several countries have already completed the transition from Analog to Digital TV Broadcasting, most of which in Europe. In South America, after several studies and trials, Brazil adopted the Japanese standard with some innovations. Japan and Brazil started Digital Terrestrial Television Broadcasting (DTTB) services in December 2003 and December 2007 respectively, using Integrated Services Digital Broadcasting - Terrestrial (ISDB-T), also known as ARIB STD-B31. In June 2005 the Committee for the Information Technology Area (CATI) of Brazilian Ministry of Science and Technology and Innovation MCTI approved the incorporation of the IC-Brazil Program, in the National Program for Microelectronics (PNM) . The main goals of IC-Brazil are the formal qualification of IC designers, support to the creation of semiconductors companies focused on projects of ICs within Brazil, and the attraction of semiconductors companies focused on the design and development of ICs in Brazil. The work presented in this thesis originated from the unique momentum created by the combination of the birth of Digital Television in Brazil and the creation of the IC-Brazil Program by the Brazilian government. Without this combination it would not have been possible to make these kind of projects in Brazil. These projects have been a long and costly journey, albeit scientifically and technologically worthy, towards a Brazilian DTV state-of-the-art low complexity Integrated Circuit, with good economy scale perspectives, due to the fact that at the beginning of this project ISDB-T standard was not adopted by several countries like DVB-T. During the development of the ISDB-T receiver proposed in this thesis, it was realized that due to the continental dimensions of Brazil, the DTTB would not be enough to cover the entire country with open DTV signal, specially for the case of remote localizations far from the high urban density regions. Then, Eldorado Research Institute and Idea! Electronic Systems, foresaw that, in a near future, there would be an open distribution system for high definition DTV over satellite, in Brazil. Based on that, it was decided by Eldorado Research Institute, that would be necessary to create a new ASIC for broadcast satellite reception. At that time DVB-S2 standard was the strongest candidate for that, and this assumption still stands nowadays. Therefore, it was decided to apply to a new round of resources funding from the MCTI - that was granted - in order to start the new project. This thesis discusses in details the Architecture and Algorithms proposed for the implementation of a low complexity Intermediate Frequency(IF) ISDB-T Receiver on Application Specific Integrated Circuit (ASIC) CMOS. The Architecture proposed here is highly based on the COordinate Rotation Digital Computer (CORDIC) Algorithm, that is a simple and efficient algorithm suitable for VLSI implementations. The receiver copes with the impairments inherent to wireless channels transmission and the receiver crystals. The thesis also discusses the Methodology adopted and presents the implementation results. The receiver performance is presented and compared to those obtained by means of simulations. Furthermore, the thesis also presents the Architecture and Algorithms for a DVB-S2 receiver targeting its ASIC implementation. However, unlike the ISDB-T receiver, only preliminary ASIC implementation results are introduced. This was mainly done in order to have an early estimation of die area to prove that the project in ASIC is economically viable, as well as to verify possible bugs in early stage. As in the case of ISDB-T receiver, this receiver is highly based on CORDIC algorithm and it was prototyped in FPGA. The Methodology used for the second receiver is derived from that used for the ISDB-T receiver, with minor additions given the project characteristics.[ES] La primera generación de Televisión Digital Terrestre(DTV) ha estado en servicio por más de una década. En 2013, varios países completaron la transición de transmisión analógica a televisión digital, la mayoría de ellas en Europa. En América del Sur, después de varios estudios y ensayos, Brasil adoptó el estándar japonés con algunas innovaciones. Japón y Brasil comenzaron a prestar el servicio de Difusión de Televisión Digital Terrestre (DTTB) en diciembre de 2003 y diciembre de 2007 respectivamente, utilizando Radiodifusión Digital de Servicios Integrados Terrestres (ISDB-T), también conocida como ARIB STD-B31. En junio de 2005, el Comité del Área de Tecnología de la Información (CATI) del Ministerio de Ciencia, Tecnología e Innovación de Brasil - MCTI aprobó la incorporación del Programa CI-Brasil, en el Programa Nacional de Microelectrónica (PNM). Los principales objetivos de la CI-Brasil son la formación de diseñadores de CIs, apoyar la creación de empresas de semiconductores enfocadas en proyectos de circuitos integrados dentro de Brasil, y la atracción de empresas de semiconductores interesadas en el diseño y desarrollo de circuitos integrados. El trabajo presentado en esta tesis se originó en el impulso único creado por la combinación del nacimiento de la televisión digital en Brasil y la creación del Programa de CI-Brasil por el gobierno brasileño. Sin esta combinación no hubiera sido posible realizar este tipo de proyectos en Brasil. Estos proyectos han sido un trayecto largo y costoso, aunque meritorio desde el punto de vista científico y tecnológico, hacia un Circuito Integrado brasileño de punta y de baja complejidad para DTV, con buenas perspectivas de economía de escala debido al hecho que al inicio de este proyecto, el estándar ISDB-T no fue adoptado por varios países como DVB-T. Durante el desarrollo del receptor ISDB-T propuesto en esta tesis, se observó que debido a las dimensiones continentales de Brasil, la DTTB no sería suficiente para cubrir todo el país con la señal de televisión digital abierta, especialmente para el caso de localizaciones remotas, apartadas de las regiones de alta densidad urbana. En ese momento, el Instituto de Investigación Eldorado e Idea! Sistemas Electrónicos, previeron que en un futuro cercano habría un sistema de distribución abierto para DTV de alta definición por satélite en Brasil. Con base en eso, el Instituto de Investigación Eldorado decidió que sería necesario crear un nuevo ASIC para la recepción de radiodifusión por satélite, basada el estándar DVB-S2. En esta tesis se analiza en detalle la Arquitectura y algoritmos propuestos para la implementación de un receptor ISDB-T de baja complejidad y frecuencia intermedia (IF) en un Circuito Integrado de Aplicación Específica (ASIC) CMOS. La arquitectura aquí propuesta se basa fuertemente en el algoritmo Computadora Digital para Rotación de Coordenadas (CORDIC), el cual es un algoritmo simple, eficiente y adecuado para implementaciones VLSI. El receptor hace frente a las deficiencias inherentes a las transmisiones por canales inalámbricos y los cristales del receptor. La tesis también analiza la metodología adoptada y presenta los resultados de la implementación. Por otro lado, la tesis también presenta la arquitectura y los algoritmos para un receptor DVB-S2 dirigido a la implementación en ASIC. Sin embargo, a diferencia del receptor ISDB-T, se introducen sólo los resultados preliminares de implementación en ASIC. Esto se hizo principalmente con el fin de tener una estimación temprana del área del die para demostrar que el proyecto en ASIC es económicamente viable, así como para verificar posibles errores en etapa temprana. Como en el caso de receptor ISDB-T, este receptor se basa fuertemente en el algoritmo CORDIC y fue un prototipado en FPGA. La metodología utilizada para el segundo receptor se deriva de la utilizada para el re[CA] La primera generació de Televisió Digital Terrestre (TDT) ha estat en servici durant més d'una dècada. En 2013, diversos països ja van completar la transició de la radiodifusió de televisió analògica a la digital, i la majoria van ser a Europa. A Amèrica del Sud, després de diversos estudis i assajos, Brasil va adoptar l'estàndard japonés amb algunes innovacions. Japó i Brasil van començar els servicis de Radiodifusió de Televisió Terrestre Digital (DTTB) al desembre de 2003 i al desembre de 2007, respectivament, utilitzant la Radiodifusió Digital amb Servicis Integrats de (ISDB-T), coneguda com a ARIB STD-B31. Al juny de 2005, el Comité de l'Àrea de Tecnologia de la Informació (CATI) del Ministeri de Ciència i Tecnologia i Innovació del Brasil (MCTI) va aprovar la incorporació del programa CI Brasil al Programa Nacional de Microelectrònica (PNM). Els principals objectius de CI Brasil són la qualificació formal dels dissenyadors de circuits integrats, el suport a la creació d'empreses de semiconductors centrades en projectes de circuits integrats dins del Brasil i l'atracció d'empreses de semiconductors centrades en el disseny i desenvolupament de circuits integrats. El treball presentat en esta tesi es va originar en l'impuls únic creat per la combinació del naixement de la televisió digital al Brasil i la creació del programa Brasil CI pel govern brasiler. Sense esta combinació no hauria estat possible realitzar este tipus de projectes a Brasil. Estos projectes han suposat un viatge llarg i costós, tot i que digne científicament i tecnològica, cap a un circuit integrat punter de baixa complexitat per a la TDT brasilera, amb bones perspectives d'economia d'escala perquè a l'inici d'este projecte l'estàndard ISDB-T no va ser adoptat per diversos països, com el DVB-T. Durant el desenvolupament del receptor de ISDB-T proposat en esta tesi, va resultar que, a causa de les dimensions continentals de Brasil, la DTTB no seria suficient per cobrir tot el país amb el senyal de TDT oberta, especialment pel que fa a les localitzacions remotes allunyades de les regions d'alta densitat urbana.. En este moment, l'Institut de Recerca Eldorado i Idea! Sistemes Electrònics van preveure que, en un futur pròxim, no hi hauria a Brasil un sistema de distribució oberta de TDT d'alta definició a través de satèl¿lit. D'acord amb això, l'Institut de Recerca Eldorado va decidir que seria necessari crear un nou ASIC per a la recepció de radiodifusió per satèl¿lit. basat en l'estàndard DVB-S2. En esta tesi s'analitza en detall l'arquitectura i els algorismes proposats per l'execució d'un receptor ISDB-T de Freqüència Intermèdia (FI) de baixa complexitat sobre CMOS de Circuit Integrat d'Aplicacions Específiques (ASIC). L'arquitectura ací proposada es basa molt en l'algorisme de l'Ordinador Digital de Rotació de Coordenades (CORDIC), que és un algorisme simple i eficient adequat per implementacions VLSI. El receptor fa front a les deficiències inherents a la transmissió de canals sense fil i els cristalls del receptor. Esta tesi també analitza la metodologia adoptada i presenta els resultats de l'execució. Es presenta el rendiment del receptor i es compara amb els obtinguts per mitjà de simulacions. D'altra banda, esta tesi també presenta l'arquitectura i els algorismes d'un receptor de DVB-S2 de cara a la seua implementació en ASIC. No obstant això, a diferència del receptor ISDB-T, només s'introdueixen resultats preliminars d'implementació en ASIC. Això es va fer principalment amb la finalitat de tenir una estimació primerenca de la zona de dau per demostrar que el projecte en ASIC és econòmicament viable, així com per verificar possibles errors en l'etapa primerenca. Com en el cas del receptor ISDB-T, este receptor es basa molt en l'algorisme CORDIC i va ser un prototip de FPGA. La metodologia utilitzada per al segon receptor es deriva de la utilitzada per al receptor IRodrigues De Lima, E. (2016). Architecture and algorithms for the implementation of digital wireless receivers in FPGA and ASIC: ISDB-T and DVB-S2 cases [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61967TESI

RAPID CLOCK RECOVERY ALGORITHMS FOR DIGITAL MAGNETIC RECORDING AND DATA COMMUNICATIONS

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN024293 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

A design strategy for phase synchronization in precoding-enabled DVB-S2X user terminals

This paper address the design of a phase tracking block for the DVB-S2X user terminals in a satellite precoding system. The spectral characteristics of the phase noise introduced by the oscillator, the channel, and the thermal noise at the receiver are taken into account. Using the expected phase noise mask, the optimal parameters for a second-order PLL intended to track channel variations from the pilots are calculated. To validate the results a Simulink model was implemented considering the characteristics of the hardware prototype. The performance of the design was evaluated in terms of the accuracy and stability for the frame structure of superframe Format 2, as described in Annex E of DVB-S2X.This work was supported by the Fond National de la Recherche Luxembourg, under the CORE project COHESAT: Cognitive Cohesive Networks of Distributed Units for Active and Passive Space Applications and the Bridges Program DISBuS: Dynamic Beam Forming and In-band Signalling for Next Generation Satellite Systems.Peer ReviewedPostprint (author's final draft

Non-linearized amplifier and advanced mitigation techniques: DVB-S2X spectral efficiency improvement

The latest standardization DVB-S2X increases the achievable spectral efficiency of the satellite communications by around 15% in AWGN channel. In order to benefit from those improvements, the strong non-linear distortions introduced by the payload have to be overcome, mostly taking high back-off on the amplifier operation point. Nowadays, on- board amplifiers are linearized before being deployed, allowing low-complexity transmitters and receivers at the detriment of the payload's cost and reduced energy efficiency. In this paper, various techniques are investigated for the purpose of spectral efficiency improvement while releasing the amplifier linearization constraint. Iterative pre-distortion at the transmitter, turbo- equalization at the receiver and appropriate waveforms for transmission through non-linearized payload appear as strong candidates considering the results of this study

Firmware de seleção de célula para redes 5G não-terrestres

The integration of satellite technology in 5G will enable networks to become more ubiquitous and reliable, extending coverage to previously underserved areas and making the network more resilient to natural catastrophes. The nonterrestrial networks (NTN) are expected to co-exist with the current terrestrial infrastructures, sharing much of the same requirements. This in turn will allow the User Equipment to connect to both, opening up new use cases and possibilities. The intent of this dissertation is to design a firmware that prepares these devices to take advantage of this new paradigm. This firmware implements an extended, radio access and backhaul-aware cell selection scheme, that chooses either to connect to terrestrial or non-terrestrial cells. The selection is based on metrics, such as, the latency and packet loss of the link, in addition to the traditional signal strength indicators. Testing the solution required deploying an end-to-end 5G network which includes not only a gNodeB (gNB) capable of simulating the propagation delay induced by long distances but also a terrestrial node. This deployment uses the OpenAirInterface (OAI) 5G software stack. With the use of this testbench, the implemented firmware was tested against key network degradation scenarios. These scenarios include, for example, the total failure of the terrestrial gNB and the steady increase of latency. The results show that this use of the firmware might help upkeep the quality of service for the User Equipment using it.A integração de tecnologias satélite nas redes 5G vai permitir que estas se tornem mais seguras e omnipresentes, estendendo a cobertura de forma a abranger áreas remotas e tornando estas redes mais resilientes contra catástrofes naturais. É expectado que as redes não-terrestres venham a coexistir com as atuais redes terrestres, partilhando os mesmos requisitos. Por sua vez isto vai permitir que os terminais se conectem a ambos, abrindo assim novas possibilidades e casos de uso. Com esta dissertação pretende-se projetar um firmware que prepare estes dispositivos para tomar partido deste novo paradigma. Este firmware funciona como uma versão estendida, ciente do backhaul, do esquema de cell selection, de forma a que este possa decidir entre conectar cells terrestres ou não terrestres. Esta decisão é informada por métricas como a latência e a perda de pacotes da ligação, além dos indicadores de força de sinal tradicionais. Para a validação desta solução foi necessário a instalação de uma rede 5G end-to-end que incluísse tanto um gNodeB (gNB) capaz de simular atraso de propagação induzido pelas longas distâncias, tal como um nó terrestre. Esta instalação usa o OpenAirInterface (OAI), uma implementação da stack 5G. Usando esta testbench, a implementação do firmware projetado foi testada face a cenários de degradação da rede. Estes incluem, por exemplo, a falha total do gNB terrestre ou um aumento crescente da latência. Os resultados obtidos mostram que o uso deste firmware poderá ajudar a manter a qualidade de serviço de um terminal que o utilize.Mestrado em Engenharia de Computadores e Telemátic

Spoofed Networks: Exploitation of GNSS Security Vulnerability in 4G and 5G Mobile Networks

Includes supplementary materialFifth Generation New Radio (5G NR) represents a shift in mobile telephony whereby the network architecture runs containerized software on commodity hardware. In preparation for this transition, numerous 4G Long Term Evolution software stacks have been developed to test the containerization of core network functions and the interfaces with radio access network protocols. In this thesis, one such stack, developed by the OpenAirInterface Software Alliance, was used to create a low-cost, simplified mobile network compatible with the Naval Operational Architecture. Commercial off-the-shelf user equipment was then connected to the network to demonstrate how a buffer overflow vulnerability found in Qualcomm Global Navigation Satellite System chipsets and identified as CVE-2019-2254 can be leveraged to enable a spoofed network attack. The research also yielded an extension of the attack method to 5G NR networks.http://archive.org/details/aplaceholderreco1094567451Lieutenant, United States NavyApproved for public release. Distribution is unlimited

Nanosatellite Store-and-Forward Communication Systems for Remote Data Collection Applications

Due to compact design, cost-effectiveness and shorter development time, a nanosatellite constellation is seen as a viable space-based data-relay asset to collect data from remote places that are rather impractical to be linked by terrestrial means. While nanosatellites have these advantages, they have more inherent technical limitations because of limited space for subsystems and payloads. Nanosatellite S&F communication systems are notably challenging in this respect due to requirements on antennas, transceivers, and signal processing. Although nanosatellites can be scaled up for better resources and capabilities, smaller platforms (i.e., ≤6U CubeSat) tend to be used for cost-effectiveness and lower risk. This thesis dealt with the problem of designing a nanosatellite S&F communication system for delay-tolerant remote data collection applications considering: (a) technical constraints in hardware, processing capabilities, energy budget and space in both the nanosatellite and ground sensor terminal (GST) sides; (b) physical communication layer characteristics and constraints such as limited available bandwidth, LEO channel Doppler, attenuation and fading/shadowing effects, low transmit power and data rate, and multi-user interference among asynchronously transmitting terminals. We designed, developed, and operated an amateur radio payload with S&F communication and APRS-DP capabilities, and performed a post-launch communication failure investigation. We also investigated suitability of E-SSA protocol for IoT/M2M terminals to nanosatellite communication by analyzing performance and energy efficiency metrics. The thesis comprises nine chapters. Chapter 1 describes the research background, problem, objectives, state of research, potential contributions of this thesis, and a gist of methodology detailed in later chapters. Chapter 2 and 3 provide an extensive literature review. Chapter 2 reviews the previous research works on using nanosatellites for S&F communication for remote data collection, and the previous nanosatellite S&F missions. Such research works and nanosatellite missions were undertaken primarily in the context of non-commercial/civil applications. Then, Chapter 2 surveys the recent commercial nanosatellite IoT/M2M players and examines their proposed systems in terms of satellite platform, constellation design, communication technology, targeted applications, requirements, and performance. Chapter 3 presents a literature review on communication system architecture, physical layer and random-access schemes, protocols, and technologies relevant to satellite IoT/M2M systems. In the context of IoT/M2M applications, the constraints in energy budget, transmit power and available bandwidth limit the system’s capacity in terms of amount of data that can be received and number of GSTs that can be supported. In both nanosatellite and GST sides, there are stringent limitations in hardware complexity, processing capabilities and energy budget. Addressing these challenges requires a simple, spectrally and energy efficient asynchronous random-access communication protocol. This research investigated using the enhanced spread spectrum Aloha (E-SSA) protocol for satellite IoT/M2M uplink (terminal to satellite) communication and analyzed its performance and suitability for the said application. Chapter 4 discusses the BIRDS-2 CubeSat S&F remote data collection system, payload design, development, tests, and integration with the BIRDS-2 CubeSats. Chapter 5 discusses the investigation on communication design issues of BIRDS-2 CubeSat S&F payload, tackling both the methodology and findings of investigation. It is noted that there are only a few satellites that have carried an APRS-DP payload but even some of these failed due to communication, power, or software issues. In BIRDS-2 Project, considering tight constraints in a 1U CubeSat equipped with other subsystems and payloads, we developed a S&F/APRS-DP payload and integrated it with each of the three 1U CubeSats of participating countries. After launching the CubeSats from the ISS, several amateur operators confirmed reception downlink beacon messages, but full two-way communication failed due to uplink communication failure. Thus, this research not only studied the design and development of a S&F/APRS-DP payload suitable for a CubeSat platform, but also systematically investigated the causes of communication failure by on-orbit observation results and ground-based tests. We found that uplink failure was caused by two design problems that were overlooked during development, namely, the poor antenna performance and increased payload receiver noise floor due to satellite-radiated EMI coupled to the antenna. Chapter 6 first describes the enhanced spread spectrum Aloha (E-SSA) based nanosatellite IoT/M2M communication model implemented in Matlab and derives the mathematical definitions of packet loss rate (PLR), throughput (THR) and energy efficiency (EE) metrics. Then, it tackles the formulated baseband signal processing algorithm for E-SSA, including packet detection, channel estimation, demodulation and decoding. Chapter 7 presents the simulation results and discussion for Chapter 6. Chapter 8 tackles the S&F nanosatellite constellation design for global coverage and presents the results and findings. Chapter 9 describes the laboratory setups for validating the E-SSA protocol and then presents the findings. Finally, Chapter 9 also gives the summary, conclusions, and recommendations. Simulation results showed that for E-SSA protocol with the formulated algorithm, THR, PLR and EE metrics are more sensitive to MAC load G, received power variation σLN and Eb/N0, due to imperfect detection and channel estimation. With loose power control (σLN=3dB), at Eb/N0=14 dB, the system can be operated up to a maximum load of 1.3 bps/Hz, achieving a maximum THR of 1.25 bps/Hz with PLR<0.03. Without power control (σLN=6dB,9dB), at Eb/N0=14 dB, maximum load is also 1.3 bps/Hz, but achievable THR is lower than ~1 bps/Hz and PLR values can be as high as ~0.23. Worse PLR results are attributed to misdetection of lower power packets and demodulation/decoding errors. Both are caused by the combined effects of MUI, channel estimation errors, imperfect interference cancellation residue power, and noise. The PLR and THR can be improved by operating with higher Eb/N0 at the expense of lower energy efficiency. Then, laboratory validation experiments using a SDR-based platform confirmed that with G=0.1, Eb/N0=14dB, σLN=6dB, the formulated algorithm for E-SSA protocol can still work even with inaccurate oscillator (±2 ppm) at GSTs, obtaining experimental PLR result of 0.0650 compared to simulation result of 0.0352. However, this requires lowering the detection thresholds and takes significantly longer processing time. For the S&F nanosatellite constellation design, it was found that to achieve the target percent coverage time (PCT) of more than 95% across all latitudes, a 9x10 Hybrid constellation or a 10x10 Walker Delta constellation would be required.九州工業大学博士学位論文 学位記番号：工博甲第506号 学位授与年月日：令和2年9月25日1: Introduction|2: Nanosatellite S&F Research, Missions and Applications|3: Satellite S&F Communication Systems and Protocols|4: BIRDS-2 CubeSat S&F Data Collection System, Payload Design and Development|5: Investigation on Communication Design Issues of BIRDS-2 CubeSat APRS-DP/S&F Payload, Results and Discussion|6: E-SSA-based Nanosatellite IoT/M2M Communication System Model and Signal Processing Algorithm|7: Simulation Results and Discussion for E-SSA-based Nanosatellite IoT/M2M Communication System|8: Nanosatellite Constellation for Global Coverage|9: Experimental Laboratory Validation for E-SSA Protocol, Research Summary, Conclusions and Recommendations九州工業大学令和2年