Is switching device a full duplex

The terms are only briefly explained here. You can find more detailed explanations on the Internet (mostly Wikipedia).


1 Glossary The terms are only briefly explained here. You can find more detailed explanations on the Internet (mostly Wikipedia). Sampling of an analog electrical signal, e.g. of an audio signal on a microphone, at equal time intervals (sampling period). The electrical voltage values ​​are converted into numbers (digital signal). Sampling rate Specifies the number of digital numbers that are produced during sampling. E.g. 10 kilobytes per second. Analog as opposed to digital. Example: An analog clock is a pointer clock, a digital clock is a clock with a number display. Analog-to-digital converter ADC An electronic circuit that converts an analog signal into a digital signal. In the mobile phone sector, 16-BIT ADCs are usually used, which generate 16-bit numbers (2 bytes per sample). Analog signal An analog signal is an electrical signal that is continuous over time, an electrical voltage that generally changes over time, e.g. at the output of a microphone. Antenna An electrical conductor, e.g. a copper rod that can send or receive electromagnetic waves. Electric charge carriers (electrons) move accelerated back and forth on the rod. Accumulator, accumulator Rechargeable electrical voltage source (battery). Lithium-ion batteries are mostly used in cell phones today. Audio signal The electrical signal that arises as a time-variable electrical voltage, for example on a microphone, into which one speaks. AuC register Authentication Center register, a database in the NSS switching subsystem, with which the user is identified (authenticated) using data and a secret key on the SIM card of the mobile phone. Base Station Controller BSC Control and monitoring system of a radio subsystem (Radio Subsystem RSS) to which the mobile radio antennas (BTS) also belong. 1

2 base station (base transceiver station BTS) antenna with transmitting / receiving device, which makes radio contact with the individual cell phone. Part of the radio subsystem (Radio Subsystem RSS). Battery, voltage source Generated in an electrical conductor, e.g. an incandescent lamp, an electric current. This is greater, the greater the electrical voltage value (in volts). Binary numbers, binary code two-digit system with the digits 0 and 1. The numbers are counted as follows: 0, 1, 10, 11, 100, 101, 110, 111, 1000 etc. (corresponds to the decimal numbers 0, 1, 2, 3, 4 , 5, 6, 7, 8,). Bit information unit (0/1, yes / no, on / off etc.) represented with the digits 0 and 1st byte 8 bits. 8-digit binary number to, decimal from 0 to 255. Cell phone English word for mobile phone / cell phone. Chutzenfeuer alarm system with high watch and fires during wartime in the old Swiss Confederation. CODEC made up word from engl. coder and decoder denote a device or a process that digitally encodes and decodes data or signals. In the simplest case, a CODEC consists of an analog-to-digital and a digital-to-analog converter, but usually also contains programs (software parts) for data compression. Cooper, Martin (* 1928) electrical engineer. Father of the cellphone. Built the world's first mobile phone at Motorola in 1973. Data compression Process for reducing the amount of data that is transferred during digital data transfer during a mobile phone call. A distinction is made between lossless and lossy data compression. During a cell phone call, the digital data is compressed approx. 10 times. Complex calculations are required for data compression, which are continuously carried out program-controlled by the cell phone's signal processor during a call. The difference between compressed and uncompressed digital data from a cell phone call is barely audible. Data transfer rate, data transfer rate Specifies the amount of data per time (in kilobits per second) e.g. can be transmitted with a GSM mobile phone. Because the data transfer rates were still too low immediately after the introduction of GSM technology (1992) to transmit the complete digital call information, data compression methods had to be used. 2

3 decimal numbers Numbers in the ten-number system composed of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, e.g. Digital as opposed to analog. A digital signal can be represented with a finite whole numerical value. E.g. between 0 and 65,535 (), i.e. with 2 bytes, digital-to-analog converter DAC An electronic circuit which converts a digital signal into an analog signal. In the mobile phone sector, 16-BIT DACs are usually used, which convert 16-bit numbers (2 bytes). Digitization A process that converts an analog, temporally variable electrical signal (e.g. from a microphone) into a corresponding temporal sequence of numbers (in electronic representation). Digital signal An electrical signal that contains a chronological sequence of numbers in an electronic representation, e.g. 10,000 numerical values ​​per second. Digital camera, digital photography Contemporary camera in which the photographic image is created on a so-called CCD sensor, which breaks the image down into individual image points (pixels) and digitizes the resulting electrical signals for the primary colors red, green and blue. Downlink connection from the base station (antenna) to the mobile phone. Dual numbers, binary numbers Number in the two-part system. E.g. decimal 13 becomes dual (binary) duplex, full-duplex two-way transmission during a telephone call. Simultaneous speaking (sending) and listening (receiving) are possible because two different frequencies are used, one for sending and the other for receiving. EDGE Enhanced Data Rates for GSM Evolution describes a technology for increasing the data transmission rate in GSM cellular networks by introducing a more efficient modulation method. Einstein, Albert () Important physicist of the 20th century. In 1905 he introduced the light quantum hypothesis (light consists of particles / photons) as well as the theory of relativity and made the claim that mass and energy are equivalent quantities .. 3

4 Electromagnetism Subfield of Classical Physics, which deals with the behavior of moving electrical charge carriers, e.g. Electrons, busy. Classical electrodynamics is determined by the four Maxwell's equations, which predict the existence of electromagnetic waves (e.g. radio waves). Electromagnetic waves arise as soon as an electrical charge carrier, e.g. an electron moving at an accelerated rate. They move in space (vacuum) at the speed of light. Electron Elementary particles with a negative electrical charge, a very small mass and a so-called spin. Electrons determine the structure of chemical bonds and play a central role in electronics. Receiver An electronic device that receives electromagnetic waves via an antenna and reproduces the information it contains (e.g. speech, music), e.g. a radio receiver. Energy Important physical quantity that is defined with the help of physical work (= force times distance). Do I lift e.g. a body of mass m and weight by a distance h, I do some work and the body then has a positional energy. The electrical energy is the product of the electrical charge q and the electrical voltage U :. Faraday, Michael () One of the most important experimental physicists. Training as a bookbinder. Faraday's discoveries of the law of electromagnetic induction laid the foundation for the production of electrical energy (generator). He introduced the basic concept of the field (electric, magnetic, electromagnetic) into physics. FDMA, Frequency Division Multiple Access. With electromagnetic waves of different frequencies, different information (e.g. different radio programs or cell phone calls) can be transmitted at the same time. Field, a mathematical function defined in each point in space. This function assigns one or more numerical values ​​to each point in space. - Electric field E is generated in the space around a static electric charge Q (e.g. an electron). A second electrical charge q experiences a force in an E-field. - Magnetic field B is generated in the space around a moving electric charge (e.g. an electron) or by an electric current (e.g. in the vicinity of a current-carrying cable). A second moving electrical charge experiences a force in a B-field. 4th

5 - Electromagnetic Is generated by an accelerated electric charge (e.g. an electron) and moves through space at the speed of light. Examples: radio waves, microwaves, visible light. Field Effect Transistor (FET) An electronic semiconductor component that can amplify an electrical current. In the FET, the resulting current intensity is determined by an electric field or by an electric voltage. Frequency f Number of oscillations per second. Unit Hertz (Hz). Frequency band, single-, dual-, tri-, quad-band phone (cell phone) Frequency range in which e.g. Cell phone calls can be established. Internationally there are four frequency bands approved for mobile phone traffic: at 850 MHz (transmitting: MHz, receiving: MHz), at 900 MHz (transmitting: MHz, receiving: MHz), at 1800 MHz (transmitting: MHz, receiving: MHz) and at 1900 MHz (sending: MHz, receiving: MHz), single, dual, tri, quad band phones work with 1, 2, 3 or 4 bands. Europe: 900MHz and 1800 MHz, USA 1900MHz and 850 MHz. In Switzerland a dual-band phone is sufficient; If you want to make phone calls in the USA, a tri-band or better a quad-band phone is required. Frequency Shift Keying (FSK) Modulation method with which digital data is transmitted, a zero e.g. at MHz, a one at MHz Gamma radiation Ionizing electromagnetic radiation emanating from radioactively decaying atomic nuclei. Incandescent metal wire (e.g. made of tungsten) that can be heated up in an air-free glass bulb that starts to glow when an electric current flows. GPRS General Packet Radio Service: General packet-oriented radio service. Term for a special type of data transmission in GSM and UMTS networks. GSM standard (GSM 900, GSM 1800, GSM 1900 and GSM 850) Global System for Mobile Communications. A standard introduced in 1992 for fully digital cellular networks, which is mainly used for telephony but also for circuit-switched and packet-switched data transmission and short messages. GSM is used worldwide in 670 networks / 200 countries (78% of all mobile phone customers). Extensions for faster data transfer: HSCSD, GPRS and EDGE 5

6 Semiconductors (e.g. silicon) Electrically relatively poorly conductive material that is used to manufacture electronic components (transistors, integrated circuits). Today the most important raw material in electronics (silicon age). Handover, handoff Handover. Process in a mobile telecommunications network (GSM, UMTS) in which the mobile device (cell phone) changes from one radio cell to another without interruption during a call or a data connection. Cellphone cellphone. Today without exception digital with the GSM or UMTS standard. Headset headphones. Allows mobile calls to be made at a greater distance from the mobile phone. This reduces the microwave exposure of the body (head). Hexadecimal numbers Number system with the 16 digits 0 to 9 and A to F. Example The hexadecimal number 9E () corresponds to the decimal number 158. HLR register Home Location Register, home register of a mobile phone number. The HLR is a database in cellular networks (GSM, UMTS). Every cell phone registered in a network and its cell phone number is stored in the HLR. The transfer of each number to the Visitor Location Register VLR carried out by the nearest base station makes it possible to locate a cell phone in a network. HSCSD High Speed ​​Circuit Switched Data, fast circuit-switched data transmission. Expansion of the GSM cellular standard for faster data transmission. IMEI (International Mobile Equipment Identification) code A 15-digit serial number used to identify GSM cell phones. IMSI (International Mobile Subscriber Identity), a 15-digit number for the unique identification of cell phone users in GSM or UMTS networks. Induction law Fundamental law of electrodynamics discovered by Michael Faraday: Electrical energy can be generated by e.g. a wire loop is moved through a magnetic field. Infrared radiation (thermal radiation) Invisible electromagnetic radiation between the microwaves and visible light. Intensity Strength of electromagnetic radiation. Corresponds to the number of 6

7 photons (light particles) emitted by an electromagnetic source. The energy of the photon is determined by the type of electromagnetic radiation. Internet Interconnected Network, a global network consisting of many computer networks through which data is exchanged. It enables the use of Internet services such as, file transfer, WWW as well as telephony, radio and television. In principle, any computer can be connected to any other computer anywhere in the world. The data exchange between the individual Internet computers takes place via the technically standardized Internet protocols (TCP / IP). Integrated circuit (IC), analog electronic circuit made up of several components (transistors, resistors, capacitors) that are applied to a piece of silicon and together form an electronic functional unit, e.g. form a hi-fi amplifier or a signal processor. A distinction is made between analog IC s (e.g. amplifiers) and digital IC s (e.g. signal processor). ICs can contain billions of components. In 2004 ICs were sold for $ 179 billion. They have been built into equipment valued at $ 1,186 billion. Interphone study Broad, international study on brain tumors and cell phone use (2010). Ionizing radiation Ultraviolet, X-ray, gamma and cosmic radiation. Electromagnetic radiation that ionizes atoms or molecules, i.e. can change their electronic structure and thus chemical compounds. Ionizing radiation is harmful to humans and animals. It increases the risk of cancer and, above a certain dose, leads to fatal radiation sickness. Ionizing radiation is often incorrectly referred to as radioactive radiation. ISDN Integrated Services Digital Network. An international standard for a digital telecommunications network. Various services such as telex (formerly: Telex), Teletex, Datex-L (circuit-switched data transmission), Datex-P (packet-switched data transmission) and telephony (fixed network) are offered via this network. Component electrical component. E.g. resistor, capacitor, coil, transistor, integrated circuit (IC). Kilby, Jack () inventor of the integrated circuit and the pocket calculator at the US company Texas Instruments in the year He is known as the father of the microchip. Nobel Prize headphones See headset. 7th

8 Capacitor Electrical component, which in principle consists of two metal plates arranged in parallel and on which electrical charge / energy can be stored. Short waves Electromagnetic waves (radio waves) in the range 3 MHz to 30 MHz (corresponds to wavelengths between 10 and 100 meters). Shortwaves make it possible to establish radio links all over the world with very low transmission powers. Longitudinal waves Electromagnetic waves (radio waves) in the range of 3 kHz to 30 kHz (corresponds to wavelengths between 10 and 100 kilometers). Used to transmit commands to submerged submarines. Long waves Electromagnetic waves (radio waves) in the range of 30 kHz to 300 kHz (corresponds to wavelengths between 1 and 10 kilometers). Loudspeaker, more dynamic Converts an amplified electrical audio signal into a sound wave. A dynamic loudspeaker consists of a conical cardboard membrane which is moved back and forth with the help of an electromagnet in time with the audio signal (50 to a maximum of times per second). Light, visible electromagnetic waves (radio waves) in the range of 400 THz to 750 THz (corresponds to wavelengths between and millimeters or 700 to 400 nanometers, or an optical spectrum with the colors red to violet). Speed ​​of light The speed with which electromagnetic waves propagate in space (in a vacuum at 300,000 km / s). The speed of light is the highest possible speed of a material body. Light quantum hypothesis Today the generally accepted assumption by Albert Einstein (1905) that light consists of quanta (particles). Light particles are called photons, Maxwell, James Clerk (), Maxwell's equations Perhaps the most important theoretician of electromagnetism. He summarized electromagnetism in four basic equations and, on the basis of his theoretical insights, predicted electromagnetic waves in 1864. They were only discovered by Heinrich Hertz in the year Membrane (e) A vibration membrane or oscillation membrane is a thin skin or foil made of metal, plastic or cardboard. the e.g. is excited electromagnetically in a loudspeaker or headphones to vibrate and generates sound waves in the surrounding air. 8th

9 Microphone A microphone converts sound into a corresponding electrical signal by dipping a coil attached to a vibrating membrane into a magnet (induction law, dynamic or moving coil microphone). In contrast, the inexpensive but good quality electret microphone that is built into cell phones is a condenser microphone. Microprocessor (MP) An integrated circuit, the function of which is determined by a program that must be transferred to the MP. The program consists of instructions (commands), e.g. add, compare two numbers or save numerical values ​​together that the MP makes available in the instruction set.A distinction is made between MP s with RISC (Reduced Instruction Set Computer) and CISC (Complex Instruction Set Computer) architecture. RISC <100 commands CISC> 100 commands. Microwaves Electromagnetic waves (radio waves) in the range of 300 MHz to 300 GHz (corresponds to wavelengths between 1 meter and 1 millimeter). Applications in mobile communications (GSM, UMTS), radar technology, WLAN, Bluetooth, satellite television, microwave ovens, etc. Medium waves Electromagnetic waves (radio waves) in the range of 300 kHz to 3 MHz (corresponds to wavelengths between 100 and 1000 meters). Mobile phone, mobile telephony mobile phone. Cell phone, radio telephone, GSM telephone, in Switzerland also Natel, engl. cell phone. Portable telephone that communicates with the telephone network via radio and can therefore be used anywhere. Before 1992, mobile telephony was operated with analog electronics and was of little importance. The revolution came in 1992 with the introduction of the digital standard GSM (Switzerland: Natel D). Modulation A process that allows information (data, speech, music, images) to be transmitted using electromagnetic waves. In the radio sector, amplitude modulation (AM) and frequency modulation (FM) are used, in digital cell phones (GSM) the method of frequency shift keying (FSK). Morse, Samuel Finley Breese () American inventor and painter. From 1837 Morse developed the first usable writing telegraph (Morseapparat) and an early Morse code. In doing so, he created the practical requirements for reliable electrical telegraphy. Morse code, Morse code Procedure for the transmission of letters, numbers and characters that are coded with a period (short signal) and dash (slightly longer signal), the letter a e.g. with a point followed by a dash. Experienced Morse telegraphists can achieve up to 300 characters per minute. 9

10 Morse code telegraph Electromechanical device for receiving and writing down electrical Morse code signals on a narrow strip of paper. MP3 actually MPEG-1 Audio Layer III or MPEG-2 Audio Layer III. A method for lossy compression of digitally stored audio data. With MP3, only those audio signals are stored and transmitted that a person can consciously perceive. This makes it possible to reduce the amount of data, which hardly reduces the perceived audio quality. MP3 is the dominant method of storing and transmitting music on computers and on the Internet. Today there are technically advanced alternatives. Mobile A, B, C, D Originally: Mational car phone. Registered trademark of Swisscom. Synonymous with the term mobile phone in Switzerland. Natel A, B and C: outdated standards in analog technology. Natel D: Current GSM standard in digital technology. Network Switching Subsystem NSS Switching subsystem to which the BSC control stations are connected (via cable or radio link). The network computer MSC within the NSS mediates calls with another cell phone on the mobile network or the fixed network of the network operator, but also the transition to other domestic or foreign networks. Non-ionizing radiation, ultraviolet, x-ray, gamma and altitude radiation. Electromagnetic radiation that ionizes atoms or molecules, i.e. can change their electronic structure and thus chemical compounds. Ionizing radiation is harmful to humans and animals. It increases the risk of cancer and, above a certain dose, leads to fatal radiation sickness. Ionizing radiation is often incorrectly referred to as radioactive radiation. Operation and Maintenance Subsystem OMS Operation and maintenance subsystem. It consists of the Service Control Point, which activates services in the overall network, the Service Order Gateway, which forms the transition to the administration of the network operator, and the Billing Gateway, which collects the data relevant to charges. Period Period of oscillation of a periodic process. If the oscillation period of a pendulum is 0.1 seconds, it oscillates at a frequency of 10 Hertz (Hz). Permanent magnet permanent magnet. Usually made of iron, nickel or cobalt or their alloys. Modern super magnets consist of alloys which contain rare earths, e.g. Neodymium included. Photon light particle is the elementary excitation (quantum) of the (quantized) electromagnetic field. In clear terms, photons are what electromagnetic radiation 10

11 exists, hence the word light particle is used in non-physical language. However, it must be noted that photons also have wave properties (electromagnetic waves). PIN code Must be entered after switching on a mobile phone. Protects against the use of the cell phone by unauthorized persons. Prepaid SIM card SIM card that does not require a subscription from the network operator. The buyer must identify himself or herself when making a purchase. Protocol Mostly internationally established method for transferring digital data between two devices. The protocol specifies how the (digital) data are transmitted, how transmission errors are checked, how (digital) data are compressed, etc. PTT: Post-Telefon-Telegraf Post und Telekom-Regiebetrieb des Bundes until 1998 (Switzerland) became the yellow giant split into Swisscom and Swiss Post and partially privatized. Radar Abbreviation for Radio Aircraft Detection and Ranging (aircraft location and distance measurement with microwaves). Describes various detection and location processes. Radio subsystem RSS (radio subsystem) Consists of several antennas (BTS), the associated radio frequency and control electronics and a network computer (BSC, Base Station Controller). Radio waves long, medium, short and ultra-short waves in the frequency range 30 kHz to 300 MHz (corresponds to wavelengths between 10 kilometers and 1 meter). Receiver Radio receiver range Local area within which a cell phone can establish a connection with a base station (and vice versa). Since the power of the (radio) transmitter of a cell phone and a base station are small, the range is a few kilometers at most. This range of the base station forms the so-called radio cell. Outside this cell, the transmitter of the associated base station is no longer effective; it can no longer be received and does not interfere if the same transmission frequency is used again by another base station. Theory of relativity Physical theory of the structure of space and time as well as gravitation. It consists of two parts created by Albert Einstein, the special relativity theory (SRT, 1905) and the general relativity theory (ART, 1916). The SRT describes the behavior of 11

12 Space and time from the point of view of observers who move relative to one another. Because the speed of light is the same for both observers, clocks do not run the same (time dilation) and the same rods appear of different lengths (length contraction). The GTR is a completely new theory of space and gravity. Roaming Describes the ability of a mobile phone customer to communicate in the network of another provider. X-rays Ionizing electromagnetic radiation with wavelengths around 0.1 nanometers (0,000 'm). X-rays are generated in an X-ray tube in which very fast electrons hit a metal sheet (e.g. made of copper) in a high vacuum and are slowed down (bremsstrahlung). SAR value Abbreviation for Specific Absorption Rate. Unit: watt per kilogram. It is a measure of the absorption of electromagnetic radiation in biological tissue. The absorption of electromagnetic field energy always leads to a warming of the tissue. Switch device for interrupting an electrical circuit. The contacts of a switch are usually tempered, e.g. silver plated. Sound waves Mechanical waves, e.g. can be generated by a loudspeaker or a musical instrument by changing the air pressure a little in time with the music. Speed ​​of sound Speed ​​at which sound waves expand in air, under normal conditions at 340 m / s. Cord telephone A toy telephone that consists of two sockets that are connected with a cord. If you speak into one of the rifles, the signal in the other rifle can also be heard over greater distances. Period of oscillation see period transmitter radio transmitter. Device that generates radio electromagnetic waves. The central element of a transmitter is the oscillating circuit, which consists of a capacitor and a coil. Service provider Mobile communications provider. In Switzerland Orange, SBB, Sunrise and Swisscom. 12th

13 SID signal (System Identification Number) A 15-bit number (worldwide between 0 and 32767, in Switzerland between 23,040 and 23,167) sent by the base stations from the mobile phone after switching on the Control channel is received and shows him whether it is in his home system. The network operator transfers the SID code to the SIM card when a mobile phone is purchased. Signal processor Particularly powerful microprocessor that is used in the mobile phone for immediate (real-time) processing of the very large stream of digital data arising during a call. The mathematical operations of addition and multiplication are particularly important for this processing. Signal processors create several hundred million multiplications and additions per second. They have separate memories for data and for programs (so-called Harvard structure). SIM card (Subscriber Identity Module) Chip card that is inserted into the mobile phone and is used to identify the user in the network. The SIM is a small microprocessor system with a memory on which a changeable number (PIN) can be saved, which protects against unauthorized use. With the help of the SIM, the mobile phone is recognized (authenticated) in a network. The SIM also contains secret data for encrypting the voice and signaling data of the cell phone. In addition, user-defined data such as a phone book, notebook and SMS can be saved. Smartphone Mobile phone that contains more computer functionality and connectivity than a conventional, advanced mobile phone: additional programs (so-called apps), camera, GPS, PDA, Internet access by the user, defined functions, etc. Voltage, electrical electrical basic quantity. Symbol: U, unit volt (V). Characterizes the strength of a battery (voltage source). Be careful when handling voltage sources above 50 volts. The electrical voltage is somewhat abstract in physics as the ratio (fraction) of the displacement work W, which has to be performed to move an electrical charge q and defines this charge: U = W / q. Voltage source, battery Electrochemical device with two electrical connections that provides electrical energy with a (more or less) constant voltage. Coil Electrical component that consists of a wire that has been wound around a non-conductive coil body (electromagnet). Coils play an important role in the transmission and reception technology for electromagnetic waves (high frequency technology). Tuning fork device for generating acoustic signals, e.g. of the tone a₁ at 440 Hertz. If you hit the tuning fork, the two prongs move against each other. 13th

14 Radiation, cosmic, high-energy, ionizing electromagnetic radiation from space with wavelengths around 1 attometer (0. 000'000 '' m). Amperage, electrical Electrical basic quantity. Symbol I, unit amperes (A). The electrical current strength is the quotient (break) between electrical charge and time. It indicates how much charge flows in a circuit per second. Circuit circuit, which in the simplest case consists of a battery (voltage source) and an electrical load, e.g. an incandescent lamp. In order for an electric current to flow, the circuit must be closed. Swisscom Swiss Telecom Society. Successor organization to the PTT. TDMA, Time Division Multiple Access Time division multiplex process in which the data (signals) from different transmitters (cell phones) are transmitted in certain time segments (time slots) on one channel. In the GSM system, so-called frames with a length of milliseconds are divided into 8 time slots with a length of milliseconds. A digitized cell phone call can be transmitted in each of these time slots. Telecommunication Describes the exchange of information over a certain distance. In the past, visible signals were transmitted for this purpose, now mostly electrical (wired) or electromagnetic signals (wireless): telephony, telegraphy, fax, mobile telephony, etc. Telephone telephones, formerly in analog relay technology, today in digital technology. Telegraph Telegraph, originally Morse telegraph (Morse code on paper strips). Telex Teleprinter Exchange, a system for sending text messages over the telephone network. It was an important means of communication for companies and authorities in the 20th century. With the advent of the forms of communication fax and it lost its importance. Sound signal Electrical signal, e.g. occurs at the connections of a microphone as soon as sound waves hit the microphone membrane. This signal is an electrical voltage (in volts) that changes over time in time with the impact of the sound. Carrier medium In physics, a medium in which a wave can propagate, water for a 14th

15 water wave, air for a sound wave. Interestingly, electromagnetic waves, e.g. Light, not a carrier medium, spreads freely in empty space. Transistor An electronic semiconductor component that can amplify an electric current. A distinction is made between the current-controlled bipolar and the voltage-controlled field effect transistor (FET). FETs (MOSFET technology) are mostly used in integrated circuits. Transmitter Sender Transceiver, TCV Combined device with transmitter and receiver that each work with different frequencies. Uplink connection from the mobile phone to the base station (antenna). Quantum of action, Planck's h physical natural constant. Relationship between the energy E of a photon and the frequency f of the associated electromagnetic radiation: h = e / f Transmission medium See carrier medium VHF (ultra-short waves) Electromagnetic waves (radio waves) in the range 30 MHz to 300 MHz (corresponds to wavelengths between 10 and 1 meter). Are for VHF broadcasting in the range 87.5 to 108 MHz and digital radio MHz (DAB, DAB Plus) ultraviolet radiation (UV) electromagnetic waves (invisible light) in the range 800 THz to 300 PHz (corresponds to wavelengths between 380 and 1 nanometer) . UV radiation below a wavelength of approx. 200 nanometers is ionizing and therefore dangerous for humans and animals. UMTS (Universal Mobile Telecommunications System) third generation (3G) mobile radio standard, with higher data transmission rates than the second generation (2G) mobile radio standard, the GSM standard. This makes video telephony and TV transmission possible. Amplifier, amplifier circuit Electronic circuit that generates an electrical signal, e.g. the sound signal of a microphone, amplified. An amplifier can amplify an electrical voltage, an electrical current, or both. The central electronic element of an amplifier is the transistor. In electronics today, full amplifiers are usually no longer built from individual components (transistors, resistors and capacitors), but ready-made integrated amplifier circuits (e.g. hi-fi amplifiers, operational amplifiers, instrument amplifiers, etc.) are used. 15th

16 VLR register (Visitor Location Register) Win location register, in which information is stored about all mobile radio subscribers who are currently in the catchment area of ​​the switching computer MSC (Mobile Service Center) of a switching subsystem (NSS). Resistance Ambiguous term. In English, a distinction is therefore made between resistor and resistance. A resistor is an electrical component, e.g. a resistance wire (e.g. constantan) or a layer of carbon on a ceramic tube that limits the electrical current of a battery in a simple circuit. Resistance R is a physical quantity (measured in ohms), the ratio between electrical voltage U (in volts) and electrical current I (in amperes): R = U / I. Wave, a spatially and temporally variable field that transports energy but no matter through space. - Rope wave If you hit a tensioned rope or a tensioned spring with a stick, the resulting disturbance spreads as a one-dimensional rope wave on the rope. - Water wave If you throw a stone into a lake, the resulting disturbance spreads as a two-dimensional wave on the water surface. - Acoustic wave (sound wave) If the membrane of a loudspeaker or the vocal folds of a human larynx periodically move back and forth in time with a sound, the air pressure is changed a little. The interference generated in this way spreads through the air as a three-dimensional sound wave at the speed of sound (approx. 340 m / s). Without a carrier medium (e.g. air) there are no sound waves. - Electromagnetic wave (e.g. microwaves or visible light). an electron, accelerated, e.g. a back and forth movement on an antenna rod creates a three-dimensional electromagnetic wave. This spreads through space at the speed of light (in a vacuum at approx. 300,000 km / s). In contrast to rope, water and sound waves, electromagnetic waves do not require a carrier medium to propagate. Wavelength Waves are often spatially periodic, i.e. their shape (e.g. the sinusoidal shape) repeats itself after a certain distance. This distance is called the wavelength. For a periodic wave, the following relationship applies: speed of propagation = wavelength by duration of shrinkage or speed of propagation = wavelength times frequency. Cell, micro cell, macro cell Mobile radio systems are built up in the form of cells. The area to be covered is divided into radio cells (micro cells, macro cells). In the center of each cell there is a base station (transmitting / receiving antenna).To subdivide a coverage area, choose 16

17 regular hexagons (honeycomb structure). Immediately neighboring radio cells use different transmission frequencies to rule out mutual interference. Radio cells that are further apart can use the same frequencies again due to the limited transmission power of the base stations. 17th