Telematics Technologies and Applications 2024 PDF

Definition of telematics Term used since 1978 - Part of computer science and electrical engineering Telematik (zusammengesetzt aus Telekommunikation und Informatik) ist eine Technik, welche die Bereiche Telekommunikation und Informatik verknüpft. Telematik ist also das Mittel der Informationsverkn...

Definition of telematics Term used since 1978 - Part of computer science and electrical engineering Telematik (zusammengesetzt aus Telekommunikation und Informatik) ist eine Technik, welche die Bereiche Telekommunikation und Informatik verknüpft. Telematik ist also das Mittel der Informationsverknüpfung von mindestens zwei Informationssystemen mit Hilfe eines Telekommunikationssystems sowie einer speziellen Datenverarbeitung. Der Begriff wurde von Nora und Minc (1978) im Rahmen ihrer Studie zur Informatisierung der Gesellschaft geprägt. … (de.wikipedia.org, 2022) Telematics is an interdisciplinary field that encompasses telecommunications, vehicular technologies (road transportation, road safety) electrical engineering (sensors, instrumentation, wireless communications, etc.), and computer science (multimedia, Internet, etc.). … (en.wikipedia.org, 2022) Telematik Technologien und Anwendungen 2024 9 Drivers of the information age in 2024 Micro-electronics Hardware to send, receive, process the data Communication technology and networks Hardware and software to encode, encrypt, transmit... Broadband access to data networks (radio, fiber …) Mobility (real and virtual) Mobile Communication Ubiquitous Computing (IoT, Digital Twins) Social, economic, legal and cultural factors Globalisation (networked economy, US vs. China) Education, access, language, mindset Wars in Europe, Middle East Legal aspects (e.g. data security, copyright, trade, criminal, competition …) Telematik Technologien und Anwendungen 2024 19 Key figures of micro-electronics (Moore‘s law) Integrated Circuits (since 1958) SIA (Semiconductor Industry Association) Int. Technology Roadmap For Semi-Conductors 1966 3 transistors (4100 3x-NOR Gate) AGP (Apollo Guidance Computer) 1978 29.000 Transistors Intel 8086 (For example in the IBM-PC from 1981) 2015 4.300.000.000 Transistors Intel's 15-core Xeon Ivy Bridge-EX 2023 19.000.000.000 Transistors Apple A17 (3nm) Telematik Technologien und Anwendungen 2024 20 Key figures of micro-electronics (Moore‘s law 1965) Telematik Technologien und Anwendungen 2024 23 Communication infrastructure in Germany Housholds 2022: approximately 41 Mio Cable Customers 2022: approximately 17 Mio (40% of households) Land line network connections 2021: 38,000,000 Fibre connections (FTTH/FTTB) 2022: 12,3 Mio Mobile Connections 2021: Approx. 150,000,000 Internet connections Households with Internet-Access 2022: approximately 40 Mio Telematik Technologien und Anwendungen 2024 24 Internet: Growth and Development Internet host computer (in the internet via IP address addressable) 1969 “4“ 1974 62 1979 188 1984 1024 1989 80,000 1994 3.800.000 2020 > 3,400,000,000 Telematik Technologien und Anwendungen 2024 25 Data/Information/Communication Data Formal representation of concepts, ideas, facts, in an appropriate manner for the processing of human/machines (Data representations: language, text, codes...) Information Meaning (semantics) of data provided by the people on the basis of conventions Information relates to human skills Data can be processed by the human/machine. Information can only be won by people. Communication Narrow: exchange of data between people (Data) Communication: A transfer of digital data between telecommunications equipment Telematik Technologien und Anwendungen 2024 29 Data vs. Signals Signals are the physical representation of data by deterministic change of values of physical variables to transfer data through time and space Real representation of abstract content Data ≠ signals Presentation Presentation Conventions Conventions Mental Models Data Signals Abstract World Physical World Telematik Technologien und Anwendungen 2024 30 Information Technology vs. Telematics Technology Information Technology Scientific/technical issues of "Information Technology" Focus on signal processing Signals Information Telematics Focus on data concept Two-stage abstraction of signals via data to information Signal Interpretation Data interpretation Signals Data Information Telematik Technologien und Anwendungen 2024 31 Computer networks: Foundation of Digital Communication Basic infrastructure for digital communication Digitalisation of all means of communication and data (text, image, language, music, video..) Modern telecommunications networks are computer networks Telematik Technologien und Anwendungen 2024 32 A few basic technical terms Topologies Connections, networks, logical topologies Communication events Communication partners, transfer procedures, usage direction, delivery sequence Time and frequency range Fourier transformation Digitisation Sampling Theorem Telematik Technologien und Anwendungen 2024 33 Topologies Spatial/organizational/logical structure of a network Network Topology How is the network structured Connection Topology How many components are connected via a transmission medium Logical Topology How is the network divided into logical subsets (administrative units...) Telematik Technologien und Anwendungen 2024 34 Connection topologies Point-to-point connections Multi-point connections Symmetrical Asymmetrical (e.g. point to multi-point) Telematik Technologien und Anwendungen 2024 35 Network topologies Full Meshing Partial Meshing Tree Circle Bus Star Example Telekom (up to 1990) ZVSt HVSt KVSt OVSt Telematik Technologien und Anwendungen 2024 36 Communication events Criteria: Participating communication partners Transmission procedure, interfaces, use the direction Delivery order/quality Telematik Technologien und Anwendungen 2024 37 Communication Partner Dialogue (Unicast, Anycast) Data exchange via a point-to-point communication A B link Multicast (group call) a comm. partner transmits at the same B time to various (mostly known) communication A C partners Broadcast D A communication partner transmits at the same time to many (mostly unknown) partners/receivers (e.g. A TV, Radio) Telematik Technologien und Anwendungen 2024 38 Transmission procedure/ Usage Direction Serial transmission Bit by bit per time interval Parallel transmission E.g. 8 bits per time interval Simplex (radio, sensors..) Duplex (phone) Half Duplex (talk) Telematik Technologien und Anwendungen 2024 39 Delivery order/Quality Classes Delivery discipline: sequence in comparison to deposit FIFO 1 2 3 4 5 6 7 8 FIFO prioritized Random Quality 7 8 1 2 3 4 5 6 Technical performance Throughput, bitrate, transmit power... 4 2 7 3 5 6 1 8 Costs Maintenance, investment, personnel, customer service Reliability Failure safety, fault tolerance, fault susceptibility Security/Protection Security from eavesdropping, authentication, integrity Telematik Technologien und Anwendungen 2024 40 Communication basics Fourier Tansformation Digitisation Sampling Theorem Telematik Technologien und Anwendungen 2024 41 Fourier tansformation Fourier analysis (Joseph M. Baron de Fourier (1768 to 1830)) Procedure for determining the share of individual harmonic vibrations at a given signal Fourier transformation Conversion of signals from time (spatial) domain to frequency domain A(t) is a periodic function of frequency f. A(t) can then be used as a superposition of an infinite number of harmonic oscillations with frequencies each representing a multiple of f (harmonics). ∞ ∞ 1 A(t) = ∑ F(i)⋅ cos(2π ⋅ (i + 1) f ⋅ t) + ∑G(i) ⋅ sin(2π ⋅ (i + 1) f ⋅ t) i= 0 4 i= 0 mit F(i) = 2 f ⋅ ∫ A(t)⋅ cos(2π ⋅ (i + 1) f ⋅ t)dt und G(i) = 2 f ⋅ ∫ A(t)⋅ sin(2π ⋅ (i + 1) f ⋅ t)dt Telematik Technologien und Anwendungen 2024 42 Fourier tansformation Sound amplitude of the word "ist„ (Time/Frequency) FT also to non-periodic functions applicable (then held a summation integration via a continuum of frequencies) All frequency components (expressed by all the Fourier coefficients) forms Time-Domain the spectrum of a signal Frequency-Domain (Spectrum) Telematik Technologien und Anwendungen 2024 43 Analog - Digital Digitalization of information 1993 3% 2000 50% 2007 94% Trend to digital signal processing-examples Why Computing technology Use, processing, distribution, development and playback in Analog Computer -> Microprocessor similar electronic data processing systems (one storage medium for all data) Telephone ISDN, switching technology, VoIP Digital data can be processed automatically Data search in digital formats is possible Mobile Communication Robustness against influences (temperature, radiation,...) GSM, UMTS, LTE, 5G Error detection and correction Image and video processing Storage space requirement Is low (compression means) JPEG, MPEG, H.265 Problems Real signals (light, sound, heat, power etc.) are analog Broadcast AD/DA conversion DAB+, DVB-S, DVB-T, DVB-H Telematik Technologien und Anwendungen 2024 44 Signal Classes Telematik Technologien und Anwendungen 2024 45 Digitisation Digitalization consists of two steps Discretization (sampling): time (spatial) equidistant measurement values of the analog signal Quantization: representation of the measured values in finite resolution (usually binary integer values, values are rounded -> Quantisation Errors) Terms Resolution The accuracy of quantization Specified in bits (16 bits = 65536 different values) For image data writes resolution usually refers to density of pixels Sampling Rate The frequency of sampling Telematik Technologien und Anwendungen 2024 46 Digitisation Telematik Technologien und Anwendungen 2024 47 Conversion to digital signals Telematik Technologien und Anwendungen 2024 48 Sampling Theorem T0 T1 T2 How often must be sampled (Sampling frequency)? Sampling Theorem ( Nyquist- or Shannon theorem): For a valid reconstruction of an analog signal from digital data the sampling rate must be at least twice the highest frequency occurring in the signal Subsampling will lead to ambiguities Oversampling (Oversampling) provides no information benefit Telematik Technologien und Anwendungen 2024 50 Sampling effects If the sampling rate is not twice as high as the highest frequency side effects occurs: Frequency - overlaps (aliasing) Due to the non-ideal low passes applies in practice: FSamp > 2.2 ·FMax Sampling Frequency for audio (for sound frequencies up to 20 kHz): 44.1 kHz Telematik Technologien und Anwendungen 2024 51 How to be sure about the highest frequency? Analog preprocessing: signal filtering Low pass filter Telematik Technologien und Anwendungen 2024 52 Measurement in dB Bel (B) is a named after Alexander Graham Bell Auxilliary unit of measurement for the identification of levels and dimensions Comparison of two values (one value with a reference) Logarithmic size Applications e.g. in the acoustics (e.g. Sound pressure level), radio frequency or signal processing (e.g. SNR) Use of the tenth part of a Bel (decibels, unit symbol dB) is common Log10(1) = 0 because 100 = 1 Log10(10) = 1 because 101 = 10 Log10(100) = 2 because 102 = 100 Telematik Technologien und Anwendungen 2024 53 Signal-to-noise ratio (SNR) Stochastic noise (statics) Quantization noise Finite resolution when digitizing (Digitisation error) Signal-to-noise distance (signal/noise ratio SNR) P = Electr. Power Measurement in dB R = Electr. Resistance (foundation is always the power value P, measurable are often the voltages U, U = Electr. Voltage therefore voltages use the factor 2) I = Electr. Current 𝑈𝑈 𝑈𝑈 𝑃𝑃 = 𝑈𝑈 ⋅ 𝐼𝐼, 𝑅𝑅 = ⇔ 𝐼𝐼 = (𝑂𝑂𝑂𝑂𝑂 𝐿𝐿𝐿𝐿𝐿𝐿) 𝐼𝐼 𝑅𝑅 𝑈𝑈 2 ⇒ 𝑃𝑃 = 𝑅𝑅 𝑈𝑈𝑆𝑆2 𝑃𝑃𝑆𝑆 𝑅𝑅 𝑈𝑈𝑆𝑆2 𝑈𝑈𝑆𝑆 𝑆𝑆𝑆𝑆𝑆𝑆(𝑑𝑑𝑑𝑑) = 10 ⋅ log( ) = 10 ⋅ log( 2 ) = 10 ⋅ log( 2 ) = 10 ⋅ log( )2 𝑃𝑃𝑁𝑁 𝑈𝑈𝑁𝑁 𝑈𝑈𝑁𝑁 𝑈𝑈𝑁𝑁 𝑅𝑅 𝑈𝑈𝑆𝑆 = 20 ⋅ log( ) 𝑈𝑈𝑁𝑁 Telematik Technologien und Anwendungen 2024 54  Signal-to-noise distance / Dynamic range Each bit resolution is a factor of 2 in the displayable number of levels and thus improve SNR by approx. 6 dB E.g. in the case of CD-Audio files: resolution when quantization with 16 bit (stereo): SNR or dynamic range = 16 x 6 = appr. 96 dB 20 ⋅ log(2) ≈ 6,0206 ≈6 Why are many sizes (Volume/Sound Pressure, Brightness..) measured in logarithmic scale? Human sensory organs also work non-linear (ear, eye) Telematik Technologien und Anwendungen 2024 55