EECS 242 Introduction Course Syllabus Course Website rfic eecs berkeley edu ee242 Grading Updated lectures homeworks solutions HW 50 Project 50 Project Proposal 5 Midterm Report 10 Final Report 35 Project Design of critical communication circuit block meeting given specification Final report due two weeks before final Two interim reports are also graded to keep you on track Students are encouraged to use material from research or industry but must demonstrate new work Tools SPICE ADS SpectreRF Matlab Mathematica Copyright Prof Ali M Niknejad EECS 242 Topics Communication System Overview Transceiver Architectures Technology Evaluation CMOS BiCMOS SiGe Modeling Choice of IF in receiver and transmitter Polar TX architectures Digitally intensive architectures Review BSIM3 4 PSP EKV Passives Inductors Transformers Linear Circuit Noise Analysis Review Design with Scattering Parameters Noise circles Gain circles Power Circles Copyright Prof Ali M Niknejad EECS 242 Topics cont Distortion and Dynamic Range Limitations Power Amplifiers Volterra Series EVM and ACPR specifications MOS non linearity MGTR and other techniques SAWless architectures Linear and Non Linear Classes Power combining Transformers Stability EVM and ACPR specs Mixers Passive mixers mixer IIP2 3 Time Varying Noise Analysis Mixer noise simulation Copyright Prof Ali M Niknejad EECS 242 Topics cont Voltage Controlled Oscillators Frequency Synthesizers Phase Noise and Jitter Quadrature VCOs Wide tuning range Crystal MEMS MOS varactors Fraq N Integer N Bandwidth Spurs Phase Noise Dividers Phase and Frequency Detection Wideband Circuit Building Blocks Copyright Prof Ali M Niknejad Introduction to Wired Wireless Introduction to Communication System Wired and Wireless Communication Overview of Antennas and Signal Propagation Channel Capacity Noise and Sensitivity Multipath propagation Copyright Prof Ali M Niknejad Model of Communication Interference Info Source Medium Info Sink Noise Information Source Analog or Digital Voice 4 kHz 4 kbps telephone Video NTSC TV 6 MHz 100 kbps 1 Mbps Mpeg Music 20 kHz 30 kbps 128 kbps MP3 Internet Traffic 1 kbps 1 5 Mbps dial up T1 Medium Twisted pair copper coaxial cables fiber free space vacuum Noise Thermal noise from Atmosphere or Active Passive Circuitry Interference Mostly from human produced sources Blockers multi path propagation non linearity and distortion Copyright Prof Ali M Niknejad Modulation and Demodulation Signals must be modulated and demodulated onto an appropriate carrier Major role of circuitry is to frequency translate amplify and filter Copyright Prof Ali M Niknejad Example Telephone Comm Telephone communication occurs over twisted pair TP wiring usually unshielded UTP Twisted pairs have better noise immunity when signals are transmitted differentially and lower radiation When cables are long relative to the wavelength of the highest frequency then they behave in a distributed manner transmission line theory This occurs because signals travel at the speed of light about 300 meters in a microsecond in air If we drive and terminate the cables in the characteristic impedance 100ohms for UTP then the cables behave properly like simple circuits and only introduce a delay and attenuation Otherwise there are multiple reflections on the line at each interface between impedances A signal at 10 MHz experiences about 30dB of attenuation when traveling 1000 ft 305 m in UTP This sets the limit to how far we can send signals before requiring gain The attenuation increases sharply with frequency Coaxial cables are much better and fiber optic cables are orders of magnitude better Copyright Prof Ali M Niknejad Data Communication LAN Dispersionless Phase Dispersion Propagation Propagation Copyright Prof Ali M Niknejad Twisting the line decreases coupling but reduces the bandwidth it s an artificial transmission line When sending high speed data through a cable we have to deal with several nonidealities Attenuation Dispersion Reflections Inter Symbol Interference Attenuation is frequency dependent and causes dispersion especially at higher frequencies The phase response of the line is also not perfectly linear constant group delay and this causes more dispersion Equalization is used at the source and receiver to compensate for the non ideality of the line But the channel has to be characterized first High Speed Chip to Chip I O Broadband mixed signal processing Simple modulation 2PAM high bandwidth 5 10Gb s Extremely energy efficient 2pJ bit Palmer ISSCC 07 Link techniques Low complexity high speed analog signal path Low speed digital control calibration Slide courtesy of Prof Elad Alon Copyright Prof Ali M Niknejad Wireless Propagation Wireless links use antennas to convert wave energy on a transmission line to free space propagating waveform 377 ohms in free space Think of an antenna as a transducer with a given input impedance efficiency gain directivity The more gain the more directive the antenna Efficient antennas are free space propagation wavelength Since many users are sharing the same channel we must contend with interference and come up with a good mechanism to share spectrum FDMA TDMA CDMA There are multiple paths from source to receiver and some objects reflect the signal ground while others scatter the signal trees Also signals creep around obstacles diffraction and hence we have to deal with multi path propagation When source receiver moves we have a Dopper shift Copyright Prof Ali M Niknejad Narrowband vs Broadband Carrier waveform sinusoid versus pulse and frequency bandwidth Narrowband modulation uses a long duration carrier and amplitude phase frequency modulation narrowband to convey information Bandwidth of signal is much lower than the carrier frequency Narrowband has been favored since spectrum can be chopped up into channels and interference is easily managed Ultrawideband uses short pulses or windowed carriers and thus occupies a very large bandwidth Energy is spread across a wideband so transmit power has to be limited to avoid interference Copyright Prof Ali M Niknejad UWB vs Narrowband Signaling Source A Baseband Impulse Ultra Wideband Transceiver Front end for Low Power Applications by Ian David O Donnell Technical Report No UCB EECS 2006 47 Copyright Prof Ali M Niknejad Impulse Radios Seem Simpler Sinusoidal Downconversion Radio A D C 90 Time Digital Processing A D C Fc Freq Subsampling Impulse Radio Time BW Fc Copyright Prof Ali M Niknejad Freq A D C Digital
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