2013 low cost high performance 24.125 ghz fmcw ranging sensor · mj product feature, 2013-02...

MJ Product Feature, 2013-02

September, 2013

LowCostandHighPerformanceKBandFMCWRangingSensorModuleMicrowavesensormodulesarethekeycomponentsinanyRadarsystem.Today,theindustryiscontinuouslyseekinglowcostandhighperformancesensorsfortargetspeed,directionandranging(distance)measurementforbothcommercialandmilitaryapplications.Someoftheapplicationsincludecollisionavoidancedetection,liquidlevelsensing,trafficcontrol,missileguidance,andobjectprofiling.SAGEMillimeterhasintroducedaKbandlowcostFMCWsensormodulewithmodelnumberSSP‐24303‐D1forspeed,directionandrangingmeasurement.TheFMCWbasedsensorisatruerangingsensor,meaningitcandetectbothstillandmovingtargetdistance.Theoperationfrequencyofthefeaturedsensor isat24.125GHz.Thesensor isbasedontraditionalTE10waveguidecavitymodeand packaged Gunn/Varactor device technology, which offers low phase noise, high frequencystability,andhighsensitivity.ComparedtoitsMMICdevice/planarcircuitbasedcounterpart,modelSSP‐24303‐D1delivers lowerharmonicandspuriousemissionandimprovedfalsesignaldetectionduetothe instinctwaveguidecut‐offnature.Theentiresensormoduleisconfiguredwithina single die‐cast aluminum housing, whichallowslowcostproduction.Figure1 is the functionblockdiagramof thefeatured FMCW sensor module. From thefunction block diagram, one can see thatthree main function components areindicated:1)Varactortunedoscillator(VTO),2) I/Q dual channel mixer, and 3) diplexer.With its unique design considerations, thefeaturedFMCWsensormodulecanbeeasilytransformed into various function moduleswithout redesigning, new circuits, oradditional tooling implementations. Forexample, if the VTO is replaced by a fixedtuned oscillator by extracting the varactordiodefromtheoscillatorcircuit,themoduleistransformedintoaDopplerspeedsensorwithdirectional detector capacity. Furthermore,

the sensor can be down‐graded to singlechannel Doppler sensor by extracting one

Figure 1, Function Block Diagram

Figure 2, Tuning Characteristics

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Schottky diode from its I or Q channel to form speed detection onlymodules for simple speedmeasurementapplications.Table 1 shows the main electrical andmechanical specifications of the featuredsensormodule. The typical output power andfrequency versus tuning voltage is shown inFigure2.Fromthetuningcurve,veryflatpoweroutput and near linear tuning characteristicsareobserved.The flatpoweroutput levelandhigh linear tuning performance are highlydesirable features for system integrators toconfigure and develop their system hard andsoftware algorithms. The featured sensormoduleisalsoequippedwithamechanicalself‐locking tuning structure for easy frequencysetting/trimming and simple frequencymechanicaladjustment.Figure3showstheI/Qchanneloutput,whichdisplayswell‐balancedandnear90degreephasedifferencebetweenthetwosignals.TheRFinterfaceofthesensormoduleisastandardWR‐42,whichallowsquickinterfacewithvariousantenna structures. SAGEMillimeter offers a variety of antennas to interfacewith the featuredsensormoduledirectly.Thesestandardantennasincludemicrostripantennas(5°x7°,5°x15°,and12° x 12° half power beamwidth) and lens corrected antenna (12° x 12° half power beamwidth)models.Allantennashaveatleast20dBsideloberejectionstoallowforproperapplications.Customdesignedantennasarealsoavailableonrequest.

Table1.SpecificationsofSSP‐24303‐D1Module

TXFrequency(GHz) 24.125TXPower(dBm,Min.) +3.0FrequencyModulationBandwidth(MHz,Min) ±150FrequencyModulationRate(KHz,Typ) 250FrequencyModulationVoltage(Volts,Typ) 0to+20MechanicalTuningBandwidth(MHz,Min) ±250ReceiverI/QPhaseΔ(Degree,Max) 90°±30°ReceiverI/QAmplitudeΔ(dB,Max) 0dB±3dBIFFrequencyRange(MHz,Min) DCto100IFOffsetVoltage(Volts,Typ) ‐0.5to‐1.0FrequencyStability(MHz/°C,Max) ‐0.80PhaseNoise(dBc/Hz@100KHzOffset,Typ) ‐95

Figure 3, I-Q Channel Display

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PowerStability(dB/°C,Max) ‐0.03OscillatorBiasVoltage/Current(Vdc/mA,Typ) +5.0/250RFConnector WR‐42Waveguide,UG595/UFlangeOscillatorBiasConnector SolderPinFrequencyModulationConnector SolderPinIFConnectors SolderPinsDimension/Weight(Typ) 0.8”Wx0.8”Hx1.0”D/1.2OzAsmentionedpreviously,many sensormodules canbe transformed from the featuredmodule’sexistingdesignandhousinghardware.SAGEMillimeteroffersmanymodelnumberstocoversensormoduleswithvariousfunctioncapacities,suchassinglechannelFMCWrangingsensor,singleanddualchannelDopplersensors,andsensorheadswithvariousintegratedantennaoptions.SAGEMillimeter,Inc. SEMICRFElectronicGmbH3043KashiwaStreet Postweg2Torrance,CA90503 D‐82024TaufkirchenTel:(424)‐757‐0168 Tel:+49‐89‐614‐1520Fax:(424)‐757‐0188 Fax:+49‐89‐614‐152‐222Email:info@sagemillimeter.comsales@semic.dewww.sagemillimeter.comwww.semic.de