Detection and Signal Processing: Technical Realization

ISBN-13: 9783642067372 / Angielski / Miękka / 2010 / 174 str.

Wilhelmus Jacobus Witteman

Opis

Thewritingofthisbookhasbeeninspiredbytheexperienceofteachinga courseonDetectionandSignalProcessingtograduatestudentsoveraperiod ofmanyyears. Itwasstrikingthatstudentswerenotonlyfascinatedbythe variousdetectionprinciplesandtechnicalperformancesofpracticalsystems, butalsobytheprofessionalismoftheinvolved typical physicalengine- ing. Usuallystudentsarethoroughlytaughtindi?erentcoursesofphysics, whicharemostlystudiedasisolated?elds. Thecourseondetectionands- nalprocessingisbasedontypicalresultsthatwereestablishedindi?erent disciplines like optics, solid state physics, thermodynamics, mathematical statistics, Fouriertransforms, andelectroniccircuitry. Theirsimultaneousand interdependentapplicationbroadenstheinsightofmutualrelationsinthev- ious?elds. Forinstancethe?uctuationsofthermalbackgroundradiationcan bederivedeitherwiththeblackbodytheoryorindependentlywithther- dynamicstoarriveatthesameresult. AlsotheappliedFourierrelationsin thefrequencyandtimedomainsarenolongerabstractmathematicalman- ulationsbutpracticaltoolsandprobablyeasiertounderstandintheapplied technique. Estimatesoftheorderofmagnitudeswithcomparisonofrelevant physicale?ectsnecessarybydesigningadeviceareveryinstructive. Ingeneral theachievementsofvariousdisciplinesarebroughttogethertodesignandto evaluatequantitativelythetechnicalperformancesofdetectiontechniques. Thustheinterestfordetectionandsignalprocessingisbothtolearnthe knowledgefordesigningpracticaldetectionsystemsandtogetacquainted withthethinkingofphysicalengineering. The?rstpartofthebookisdevotedtonoisephenomenaandradiation detectors. Fundamentaldescriptionswithquantitativeanalysesoftheund- lyingphysicalprocessesofbothdetectorsandaccompanyingnoiseleadto understandthepotentialswithrespecttosensitivityandoperatingfrequency domain. Thesecondpartdealswithampli?cationproblemsandtherecovery ofrepetitivesignalsburiedinnoise. Thelastpartisdevotedtosolvingthe problemsconnectedwithreachingtheultimatedetectionlimitorquantum limit. Thisisdoneforheterodynedetectionandphotoncounting. Although VIII Preface heterodynedetectionyieldstheultimatesensitivity, itsspatialmodesel- tivityand, ingeneral, thelowspectralpowerdensityofthesignalrequire sophisticatedprovisions. Thisisdiscussedindetail. Theinherentproblemsare analyzedandappropriatetechnicalsolutionsaredescribedtoreachtheul- matesensitivityfordetectingincoherentradiationandcommunicationsignals thatarerandomlyDopplershifted. Theresultsareillustratedwithexamples ofspacecommunication. Hengelo(O), January2006 W. J. Witteman Contents 1 RandomFluctuations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1. 1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1. 2 ThermalNoiseofResistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. 3 ShotNoise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. 3. 1 SpectralDistribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1. 3. 2 Photons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1. 4 FlickerNoise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1. 5 Generation RecombinationNoise. . . . . . . . . . . . . . . . . . . . . . . . . . 10 1. 6 ThermalRadiationandItsFluctuations. . . . . . . . . . . . . . . . . . . . 13 1. 7 TemperatureFluctuationsofSmallBodies. . . . . . . . . . . . . . . . . . 18 1. 7. 1 AbsorptionandEmissionFluctuations. . . . . . . . . . . . . . . 20 2 Signal NoiseRelations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2. 1 SignalLimitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2. 2 BackgroundLimitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2. 2. 1 IdealDetection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2. 3 JohnsonNoise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2. 4 DarkCurrentNoise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2. 5 NoiseandSensitivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2. 6 Ampli?erNoiseandMismatching. . . . . . . . . . . . . . . . . . . . . . . . . . 28 3 ThermalDetectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 3. 1 ThermocoupleandThermopile. . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 3. 2 Bolometer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 3. 2. 1 MetallicBolometer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 3. 2. 2 Thermistor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3. 3 PyroelectricDetector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 4 VacuumPhotodetectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 4. 1 VacuumPhotodiode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 4. 2 Photomultiplier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 X Contents 5 SemiconductorPhotodetectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 5. 1 Photoconductors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 5. 1. 1 AnalysisoftheDetectionProcess. . . . . . . . . . . . . . . . . . . . 64 5. 1. 2 FrequencyResponse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 5. 2 Photodiodes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 5. 2. 1 P NJunction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 5. 2. 2 Current VoltageCharacteristic. . . . . . . . . . . . . . . . . . . . . . 72 5. 2. 3 PhotonExcitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 5. 2. 4 Op

Spis treści

Random Fluctuations.- Signal–Noise Relations.- Thermal Detectors.- Vacuum Photodetectors.- Semiconductor Photodetectors.- Correlation Analyses.- Signal Processing.- Heterodyne Detection.- Fast Detection of Weak and Noisy Signals.

O autorze

W. J. Witteman has been professor in laser physics at the University of Twente (The Netherlands) from 1969 until 1999. Next to numerous articles in the field of CO2-lasers, excimer lasers and free electron lasers he has published:

In 1987 "The CO2 Laser" (Springer Series in Optical Sciences, Vol.54)

In 1996 as co-author "Gas Lasers-Recent Developments and Future Prospects" (Kluwer Academic Publishers)

In 2004 as co-author "Handbook of Laser Technology & Applications" (Institute of Physics Publishing). He was the author of the chapter on "Excimer, F2, N2 and H2 Lasers".

Blurb

This comprehensive monograph deals with detectors, signal processors and related noise phenomena. Detailed quantitative analyses are developed in a consistent format for thermal detectors, vacuum detectors, semiconductor detectors and avalanche detectors, as well as their accompanying noise currents. For signal processing applocations, the monograph treats in detail the operational amplifier, signal averagers, waveform analyzers, correlation techniques and heterodyne detection. Several original extensions are reported, especially for correlation devices and heterodyne detection with noise rejection. In addition, results of analyses are illustrated with examples of operating systems and of applications in space communication and laser radar.