Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/Wireless Transmission Frequencies Signals Antenna Signal propagation

Multiplexing Spread spectrum Modulation

Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/

Frequencies for communicationVLF = Very Low FrequencyUHF = Ultra High FrequencyLF = Low Frequency SHF = Super High FrequencyMF = Medium Frequency EHF = Extra High FrequencyHF = High Frequency UV = Ultraviolet LightVHF = Very High Frequency

Frequency and wave length: = c/f wave length , speed of light c 3x108m/s, frequency f1 Mm300 Hz10 km30 kHz100 m3 MHz1 m300 MHz10 mm30 GHz100 m3 THz1 m300 THzvisible lightVLFLFMFHFVHFUHFSHFEHFinfraredUVoptical transmissioncoax cabletwisted pair

Frequencies for mobile communicationVHF-/UHF-ranges for mobile radiosimple, small antenna for carsdeterministic propagation characteristics, reliable connectionsSHF and higher for directed radio links, satellite communicationsmall antenna, focusinglarge bandwidth availableWireless LANs use frequencies in UHF to SHF spectrumsome systems planned up to EHFlimitations due to absorption by water and oxygen molecules (resonance frequencies)weather dependent fading, signal loss caused by heavy rainfall etc.

Signals Iphysical representation of datafunction of time and locationsignal parameters: parameters representing the value of data classificationcontinuous time/discrete timecontinuous values/discrete valuesanalog signal = continuous time and continuous valuesdigital signal = discrete time and discrete valuessignal parameters of periodic signals: period T, frequency f=1/T, amplitude A, phase shift sine wave as special periodic signal for a carrier: s(t) = At sin(2 ft t + t)

Fourier representation of periodic signals1010ttideal periodic signalreal composition(based on harmonics)

Different representations of signals amplitude (amplitude domain)frequency spectrum (frequency domain)phase state diagram (amplitude M and phase in polar coordinates)

Composed signals transferred into frequency domain using Fourier transformationDigital signals needinfinite frequencies for perfect transmission modulation with a carrier frequency for transmission (analog signal!) Signals IIf [Hz]A [V]I= M cos Q = M sin A [V]t[s]

Radiation and reception of electromagnetic waves, coupling of wires to space for radio transmissionIsotropic radiator: equal radiation in all directions (three dimensional) - only a theoretical reference antennaReal antennas always have directive effects (vertically and/or horizontally) Radiation pattern: measurement of radiation around an antenna

Antennas: isotropic radiatorzyxzyxidealisotropicradiator

Antennas: simple dipolesReal antennas are not isotropic radiators but, e.g., dipoles with lengths /4 on car roofs or /2 as Hertzian dipole shape of antenna proportional to wavelength

Example: Radiation pattern of a simple Hertzian dipole

Gain: maximum power in the direction of the main lobe compared to the power of an isotropic radiator (with the same average power)

side view (xy-plane)xyside view (yz-plane)zytop view (xz-plane)xzsimpledipole/4/2

Antennas: directed and sectorizedside view (xy-plane)xyside view (yz-plane)zytop view (xz-plane)xztop view, 3 sectorxztop view, 6 sectorxzOften used for microwave connections or base stations for mobile phones (e.g., radio coverage of a valley)directedantennasectorizedantenna

Antennas: diversityGrouping of 2 or more antennasmulti-element antenna arraysAntenna diversityswitched diversity, selection diversityreceiver chooses antenna with largest outputdiversity combiningcombine output power to produce gaincophasing needed to avoid cancellation

+/4/2/4ground plane/2/2+/2

Signal propagation rangesdistancesendertransmissiondetectioninterferenceTransmission rangecommunication possiblelow error rateDetection rangedetection of the signal possibleno communication possibleInterference rangesignal may not be detected signal adds to the background noise

Signal propagationPropagation in free space always like light (straight line)Receiving power proportional to 1/d (d = distance between sender and receiver)Receiving power additionally influenced byfading (frequency dependent)shadowingreflection at large obstaclesrefraction depending on the density of a mediumscattering at small obstaclesdiffraction at edgesreflectionscatteringdiffractionshadowingrefraction

Real world example

Signal can take many different paths between sender and receiver due to reflection, scattering, diffraction

Time dispersion: signal is dispersed over time interference with neighbor symbols, Inter Symbol Interference (ISI)

The signal reaches a receiver directly and phase shifted distorted signal depending on the phases of the different partsMultipath propagationsignal at sendersignal at receiverLOS pulsesmultipathpulses

Effects of mobilityChannel characteristics change over time and location signal paths changedifferent delay variations of different signal partsdifferent phases of signal parts quick changes in the power received (short term fading)

Additional changes indistance to senderobstacles further away slow changes in the average power received (long term fading)short term fadinglong termfadingtpower

Multiplexing in 4 dimensionsspace (si)time (t)frequency (f)code (c)

Goal: multiple use of a shared medium

Important: guard spaces needed!s2s3s1Multiplexingftck2k3k4k5k6k1ftcftcchannels ki

Frequency multiplexSeparation of the whole spectrum into smaller frequency bandsA channel gets a certain band of the spectrum for the whole timeAdvantages:no dynamic coordination necessaryworks also for analog signals

Disadvantages:waste of bandwidth if the traffic is distributed unevenlyinflexibleguard spaces

k2k3k4k5k6k1ftc

ftck2k3k4k5k6k1Time multiplexA channel gets the whole spectrum for a certain amount of time

Advantages:only one carrier in the medium at any timethroughput high even for many users

Disadvantages:precise synchronization necessary

fTime and frequency multiplexCombination of both methodsA channel gets a certain frequency band for a certain amount of timeExample: GSM Advantages:better protection against tappingprotection against frequency selective interferencehigher data rates compared to code multiplexbut: precise coordination requiredtck2k3k4k5k6k1

Code multiplexEach channel has a unique code

All channels use the same spectrum at the same timeAdvantages:bandwidth efficientno coordination and synchronization necessarygood protection against interference and tappingDisadvantages:lower user data ratesmore complex signal regenerationImplemented using spread spectrum technologyk2k3k4k5k6k1ftc

ModulationDigital modulationdigital data is translated into an analog signal (baseband)ASK, FSK, PSK - main focus in this chapterdifferences in spectral efficiency, power efficiency, robustnessAnalog modulationshifts center frequency of baseband signal up to the radio carrierMotivationsmaller antennas (e.g., /4)Frequency Division Multiplexingmedium characteristicsBasic schemesAmplitude Modulation (AM)Frequency Modulation (FM)Phase Modulation (PM)

Modulation and demodulationsynchronizationdecisiondigitaldataanalogdemodulationradiocarrieranalogbasebandsignal101101001radio receiverdigitalmodulationdigitaldataanalogmodulationradiocarrieranalogbasebandsignal101101001radio transmitter

Digital modulationModulation of digital signals known as Shift KeyingAmplitude Shift Keying (ASK):very simplelow bandwidth requirementsvery susceptible to interference Frequency Shift Keying (FSK):needs larger bandwidth

Phase Shift Keying (PSK):more complexrobust against interference101t101t101t

Advanced Frequency Shift Keyingbandwidth needed for FSK depends on the distance between the carrier frequenciesspecial pre-computation avoids sudden phase shifts MSK (Minimum Shift Keying)bit separated into even and odd bits, the duration of each bit is doubled depending on the bit values (even, odd) the higher or lower frequency, original or inverted is chosenthe frequency of one carrier is twice the frequency of the otherEquivalent to offset QPSK

even higher bandwidth efficiency using a Gaussian low-pass filter GMSK (Gaussian MSK), used in GSM

Example of MSKdataeven bitsodd bits1111000tlow frequencyhigh frequencyMSKsignalbiteven0 1 0 1odd0 0 1 1signalh n n h value- - + +h: high frequencyn: low frequency+: original signal-: inverted signalNo phase shifts!

Advanced Phase Shift KeyingBPSK (Binary Phase Shift Keying):bit value 0: sine wavebit value 1: inverted sine wavevery simple PSKlow spectral efficiencyrobust, used e.g. in satellite systemsQPSK (Quadrature Phase Shift Keying):2 bits coded as one symbolsymbol determines shift of sine waveneeds less bandwidth compared to BPSKmore complexOften also transmission of relative, not absolute phase shift: DQPSK - Differential QPSK (IS-136, PHS)

11100001At

Quadrature Amplitude ModulationQuadrature Amplitude Modulation (QAM): combines amplitude and phase modulationit is possible to code n bits using one symbol2n discrete levels, n=2 identical to QPSKbit error rate increases with n, but less errors compared to comparable PSK schemes

Example: 16-QAM (4 bits = 1 symbol)Symbols 0011 and 0001 have the same phase , but different amplitude a. 0000 and 1000 have different phase, but same amplitude. used in standard 9600 bit/s modems0000000100111000QI0010a

Hierarchical ModulationDVB-T modulates two separate data streams onto a single DVB-T streamHigh Priority (HP) embedded within a Low Priority (LP) streamMulti carrier system, about 2000 or 8000 carriersQPSK, 16 QAM, 64QAMExample: 64QAMgood reception: resolve the entire 64QAM constellationpoor reception, mobile reception: resolve only QPSK portion6 bit per QAM symbol, 2 most significant determine QPSKHP service coded in QPSK (2 bit), LP uses remaining 4 bitQI0010000010010101

Spread spectrum technologyProblem of radio transmission: frequency dependent fading can wipe out narrow band signals for duration of the interference

Solution: spread narrow band signal into broad band signal using special code

protection against narrowband interference

Side effects:coexistence of several signals without dynamic coordinationtap-proof

Alternatives: Direct Sequence, Frequency Hopping

detection atreceiverinterferencespread signalsignalspreadinterferenceffpowerpower

Effects of spreading and interferencedP/dffi)dP/dffii)senderdP/dffiii)dP/dffiv)receiverfv)user signalbroadband interferencenarrowband interferencedP/df

Spreading and frequency selective fadingfrequencychannel quality123456narrow band signalguard spacenarrowband channelsspread spectrum channels

DSSS (Direct Sequence Spread Spectrum) IXOR of the signal with pseudo-random number (chipping sequence)many chips per bit (e.g., 128) result in higher bandwidth of the signalAdvantagesreduces frequency selective fadingin cellular networks base stations can use the same frequency rangeseveral base stations can detect and recover the signalsoft handoverDisadvantagesprecise power control necessaryuser datachipping sequenceresultingsignal0101101010100111XOR01100101101001=tbtctb: bit periodtc: chip period

DSSS (Direct Sequence Spread Spectrum) IIXuser datachippingsequencemodulatorradiocarrierspreadspectrumsignaltransmitsignaltransmitterdemodulatorreceivedsignalradiocarrierXchippingsequencelowpassfilteredsignalreceiverintegratorproductsdecisiondatasampledsumscorrelator

FHSS (Frequency Hopping Spread Spectrum) IDiscrete changes of carrier frequencysequence of frequency changes determined via pseudo random number sequenceTwo versionsFast Hopping: several frequencies per user bitSlow Hopping: several user bits per frequencyAdvantagesfrequency selective fading and interference limited to short periodsimple implementationuses only small portion of spectrum at any timeDisadvantagesnot as robust as DSSSsimpler to detect

FHSS (Frequency Hopping Spread Spectrum) IIuser dataslowhopping(3 bits/hop)fasthopping(3 hops/bit)01tb011tff1f2f3ttdff1f2f3ttdtb: bit periodtd: dwell time

FHSS (Frequency Hopping Spread Spectrum) IIImodulatoruser datahoppingsequencemodulatornarrowbandsignalspreadtransmitsignaltransmitterreceivedsignalreceiverdemodulatordatafrequencysynthesizerhoppingsequencedemodulatorfrequencysynthesizernarrowbandsignal

Physical layer

Holger Karl

Receiver: DemodulationThe receiver looks at the received wave form and matches it with the data bit that caused the transmitter to generate this wave formNecessary: one-to-one mapping between data and wave formBecause of channel imperfections, this is at best possible for digital signals, but not for analog signalsProblems caused byCarrier synchronization: frequency can vary between sender and receiver (drift, temperature changes, aging, )Bit synchronization (actually: symbol synchronization): When does symbol representing a certain bit start/end?Frame synchronization: When does a packet start/end? Biggest problem: Received signal is not the transmitted signal!

Attenuation results in path lossEffect of attenuation: received signal strength is a function of the distance d between sender and transmitterCaptured by Friis free-space equationDescribes signal strength at distance d relative to some reference distance d0 < d for which strength is known d0 is far-field distance, depends on antenna technology

To take into account stronger attenuation than only caused by distance (e.g., walls, ), use a larger exponent > 2 is the path-loss exponent

Rewrite in logarithmic form (in dB):

Take obstacles into account by a random variationAdd a Gaussian random variable with 0 mean, variance 2 to dB representationEquivalent to multiplying with a lognormal distributed r.v. in metric units ! lognormal fading Generalizing the attenuation formula

Noise and interferenceSo far: only a single transmitter assumedOnly disturbance: self-interference of a signal with multi-path copies of itself

In reality, two further disturbancesNoise due to effects in receiver electronics, depends on temperatureTypical model: an additive Gaussian variable, mean 0, no correlation in time Interference from third partiesCo-channel interference: another sender uses the same spectrumAdjacent-channel interference: another sender uses some other part of the radio spectrum, but receiver filters are not good enough to fully suppress it

Effect: Received signal is distorted by channel, corrupted by noise and interferenceWhat is the result on the received bits?

Symbols and bit errorsExtracting symbols out of a distorted/corrupted wave form is fraught with errorsDepends essentially on strength of the received signal compared to the corruption Captured by signal to noise and interference ratio (SINR)

SINR allows to compute bit error rate (BER) for a given modulationAlso depends on data rate (# bits/symbol) of modulation E.g., for simple DPSK, data rate corresponding to bandwidth:

Examples for SINR BER mappingsBERSINR

Channel models analog How to stochastically capture the behavior of a wireless channelMain options: model the SNR or directly the bit errors

Signal modelsSimplest model: assume transmission power and attenuation are constant, noise an uncorrelated Gaussian variable Additive White Gaussian Noise model, results in constant SNR

Situation with no line-of-sight path, but many indirect paths: Amplitude of resulting signal has a Rayleigh distribution (Rayleigh fading)

One dominant line-of-sight plus many indirect paths: Signal has a Rice distribution (Rice fading)

Channel models digital Directly model the resulting bit error behavior Each bit is erroneous with constant probability, independent of the other bits binary symmetric channel (BSC)

Capture fading models property that channel be in different states Markov models states with different BERsExample: Gilbert-Elliot model with bad and good channel states and high/low bit error rates

Fractal channel models describe number of (in-)correct bits in a row by a heavy-tailed distribution

goodbad

WSN-specific channel modelsTypical WSN propertiesSmall transmission rangeImplies small delay spread (nanoseconds, compared to micro/milliseconds for symbol duration) Frequency-non-selective fading, low to negligible inter-symbol interferenceCoherence bandwidth often > 50 MHz Some example measurements path loss exponentShadowing variance 2 Reference path loss at 1 m

Wireless channel quality summary Wireless channels are substantially worse than wired channelsIn throughput, bit error characteristics, energy consumption,

Wireless channels are extremely diverseThere is no such thing as THE typical wireless channel

Various schemes for quality improvement existSome of them geared towards high-performance wireless communication not necessarily suitable for WSN, ok for MANETDiversity, equalization, Some of them general-purpose (ARQ, FEC)Energy issues need to be taken into account!

Some transceiver design considerationsStrive for good power efficiency at low transmission powerSome amplifiers are optimized for efficiency at high output powerTo radiate 1 mW, typical designs need 30-100 mW to operate the transmitterWSN nodes: 20 mW (mica motes)Receiver can use as much or more power as transmitter at these power levels ! Sleep state is importantStartup energy/time penalty can be highExamples take 0.5 ms and 60 mW to wake up Exploit communication/computation tradeoffsMight payoff to invest in rather complicated coding/compression schemes

Choice of modulationOne exemplary design point: which modulation to use?Consider: required data rate, available symbol rate, implementation complexity, required BER, channel characteristics, Tradeoffs: the faster one sends, the longer one can sleepPower consumption can depend on modulation schemeTradeoffs: symbol rate (high?) versus data rate (low)Use m-ary transmission to get a transmission over with ASAPBut: startup costs can easily void any time saving effectsFor details: see example in exercise!

Adapt modulation choice to operation conditionsAkin to dynamic voltage scaling, introduce Dynamic Modulation Scaling

SummaryWireless radio communication introduces many uncertainties and vagaries into a communication system

Handling the unavoidable errors will be a major challenge for the communication protocols

Dealing with limited bandwidth in an energy-efficient manner is the main challenge

MANET and WSN are pretty similar hereMain differences are in required data rates and resulting transceiver complexities (higher bandwidth, spread spectrum techniques)

Wireless CommunicationsPrinciples and Practice2nd EditionT.S. Rappaport

Chapter 4: Mobile Radio Propagation: Large-Scale Path Loss

Co-channel and Adjacent Channel Interference, Propagation

Small-scale and large-scale fadingFigure 4.1 Small-scale and large-scale fading.

Typical electromagnetic properties

Typical large-scale path loss

Measured large-scale path loss

Partition losses

Partition losses

Partition losses

Wireless CommunicationsPrinciples and Practice2nd EditionT.S. Rappaport

Chapter 5: Mobile Radio Propagation: Small-Scale Fading and Multipath as it applies to Modulation Techniques

Channel Sounder: Pulse type

Channel Sounder: PN Type

Typical RMS delay spreads

Two independent fading issues

Flat-fading (non-freq. Selective)

Frequency selective fading

Two independent fading issues

Rayleigh fading

Small-scale envelope distributions

Ricean and Rayleigh fading distributions

Wireless CommunicationsPrinciples and Practice2/eT.S. RapppaportChapter 6: Modulation Techniques for Mobile Radio

Amplitude Modulation

Double Sideband Spectrum

SSB Modulators

Tone-in Band SSB

Product Detection

VCO circuit

Wideband FM generation

Slope Detector for FM

Digital Demod for FM

PLL Demod for FM

Phase-shift quadrature FM demod

FM Demod circuit

Line Coding spectra

RZ and NRZ Line Codes

Nyquist Pulses for zero-ISI

Raised Cosine Spectrum

Spectrum of Raised Cosine pulse

Raised Cosine pulses

RF signal usig Raised Cosine

Gaussian pulse-shapes

BPSK constellation

Virtue of pulse shaping

BPSK Coherent demodulator

Differential PSK encoding

DPSK modulation

DPSK receiver

QPSK constellation diagrams

Virtues of Pulse Shaping

QPSK modulation

QPSK receiver

Offset QPSK waveforms

Pi/4 QPSK signaling

Pi/4 QPSK phase shifts

Pi/4 QPSK transmitter

Differential detection of pi/4 QPSK

IF Differential Detection

FM Discriminator detector

FSK Coherent Detection

Noncoherent FSK

Minimum Shift Keying spectra

MSK modulation

MSK reception

GMSK spectral shaping

GMSK spectra shaping

Simple GMSK generation

GMSK Demodulator

Digital GMSK demodulator

8-PSK Signal Constellation

Bandwidth vs. Power Efficiency

Pulse Shaped M-PSK

16-QAM Signal Constellation

QAM efficiencies

M-ary FSK efficiencies

PN Sequence Generator

Direct Sequence Spread Spectrum

Direct Sequence Spreading

Frequency Hopping Spread Spectrum

CDMA Multiple Users

Effects of Fading

Irreducible Bit Error Rate due to multipath

Irreducible Bit Error Rate due to multipath

Simulation of Fading and Multipath

Irreducible BER due to fading

Irreducible BER due to fading

BER due to fading & multipath

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Energy per bit as a function of modulation and packet size (Raghunathan et al)

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Slides from Rahul Mangaram

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Shannons Capacity TheoremStates the theoretical maximum rate at which an error-free bit can be transmitted over a noisy channel

C: the channel capacity in bits per secondB: the bandwidth in hertzSNR: the ratio of signal power to noise power

Channel capacity depends on channel bandwidth and system SNR

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*Shannons Theorem: ExampleFor SNR of 0, 10, 20, 30 dB, one can achieve C/B of 1, 3.46, 6.66, 9.97 bps/Hz, respectively

Example:Consider the operation of a modem on an ordinary telephone line. The SNR is usually about 1000. The bandwidth is 3.4 KHz. Therefore:

C = 3400 X log2(1 + 1000) = (3400)(9.97) 34 kbps

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*Bit Error RateBER = Errors / Total number of bitsError means the reception of a 1 when a 0 was transmitted or vice versa.

Noise is the main factor of BER performance signal path loss, circuit noise,

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*Thermal NoiseThermal Noisewhite noise since it contains the same level of power at all frequencieskTB, wherek is the Boltzmanns constant = 1.381e-21 W / K / Hz,T is the absolute temperature in Kelvin, and B is the bandwidth.

At room temperature, T = 290K, the thermal noise power spectral density,kT = 4.005e-21 W/Hz or 174 dBm/Hz

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*Receiver SensitivityThe minimum input signal power needed at receiver input to provide adequate SNR at receiver output to do data demodulation

SNR depends onReceived signal powerBackground thermal noise at antenna (Na)Noise added by the receiver (Nr)

Pmin = SNRmin (Na +Nr)

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*Noise FigureNoise Figure (F) quantifies the increase in noise caused by the noise source in the receiver relative to input noise

F = SNRinput/SNRoutput = (Na + Nr)/Na Pmin = SNRmin(Na + Nr) = SNRminF Na

Example: if SNRmin = 10 dB, F = 4 dB, BW = 1 MHz Pmin= 10 + 4 -174 + 10log(106) = -100 dBm

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*802.15.4 - Modulation Scheme2.4 GHz PHY 250 kb/s (4 bits/symbol, 62.5 kBaud) Data modulation is 16-ary orthogonal O-QPSK 16 symbols are ~orthogonal set of 32-chip PN codes

868 MHz/915 MHz PHY Symbol rate 868 MHz band: 20 kbps (1bit/symbol, 20 Kbaud) 915 MHz band: 40 kbps (1bit/symbol, 40 Kbaud) Spreading code is 15-chip Data modulation is BPSK 868 MHz: 300 Kchips/s 915 MHz: 600 Kchips/s

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802.15.4 - PHY Communication ParametersTransmit powerCapable of at least 0.5 mWTransmit center frequency tolerance 40 ppm Receiver sensitivity (packet error rate < 1%) 85 dBm @ 2.4 GHz band 92 dBm @ 868/915 MHz band Receiver Selectivity 2.4 GHz: 5 MHz channel spacing, 0 dB adjacent channel requirement Channel Selectivity and Blocking915 MHz and 2.4 GHz band: 0 dB rejection of interference from adjacent channel 30 dB rejection of interference from alternate channelRx Signal Strength Indication MeasurementsPacket strength indicationClear channel assessmentDynamic channel selection

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*802.15.4: Receiver Noise Figure CalculationChannel Noise bandwidth is 1.5 MHzTransmit Power is 1mW or 0 dBmThermal noise floor is 174 dBm/Hz X 1.5 MHz = 112 dBmTotal SNR budget is 0 dBm (112 dBm) = 112 dBm To cover ~100 ft. at 2.4 GHz results in a path loss of 40 dBi.e. Receiver sensitivity is 85 dBm

Required SNR for QPSK is 12.5 dB 802.15.4 packet length is 1KbWorst packet loss < 1%, (1 BER)1024= 1 1%, BER = 105 Receiver noise figure requirement NF = Transmit Power Path Loss Required SNR Noise floor = 0 + 112 40 12.5 = 59.5 dBThe design spec is very relaxedLow transmit power enables CMOS single chip solution at low cost and power!

Universitt KarlsruheInstitut fr TelematikUniversitt KarlsruheInstitut fr TelematikMobilkommunikationSS 1998Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. Schiller*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.15Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.4Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.8Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.9Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.10Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.11Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.12Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.13Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.14Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 3.2Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.3Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.4Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.5Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.6Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.7Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.8Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.9Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.10Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.11Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.12Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.13Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.13Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.14Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.15Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 3.2Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.3Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.4Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.5Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.6Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.7Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.8Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.9Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.10Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.11Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.12Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.13Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.14Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.15Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. SchillerUniversitt KarlsruheInstitut fr Telematik*Fig. 2.16Prof. Dr. Dr. h.c. G. KrgerE. Dorner / Dr. J. Schiller