MARINERADARANDARPAChapter1

BasicPrincipleofRadarChapter1 BasicPrincipleofRadarTheDevelopment&PrincipleofMarineRadarRadarConceptThedevelopmentofradartechniqueTheuseofradaratseaGeneralDescriptionTheprincipleofrangeandbearingmeasurementDisplaypresentationofabasicradarChapter1 BasicPrincipleofRadarRadarConceptGeneralConceptRadar——RadiodetectionandrangingFromthename:Tofindandmeasurethetargetsthatyouconcernaboutbywayofradiomagneticwave.Scientificdefinition:Radarisakindofelectronicsystemwhichcanbeusedtofindthetargetsandtomeasureordeterminatethetargetsinformation/databywayofthecharacteristicsofelectromagneticwave.Chapter1 BasicPrincipleofRadarThecharacteristicofelectromagneticwave:

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ReflactionFind:Reflect\Relay\RadiateTargets:Alltheobjectsthatcanbefoundbyradar.Targetsinformation/data:positionspeed,course,collisionavoidanceinformationconstantspeedstraightlineChapter1 BasicPrincipleofRadar雷達是一種主動遙感設備，它利用電磁波的二次輻射、轉發或固有輻射來探測目標，并測定目標的空間坐標、速度及避碰參數的一個無線電技術范圍。稱為“雷達”?！岸屋椛洹保豪走_發射電磁波到目標后、目標產生“二次輻射”，其中一小部分被雷達天線接收，稱為目標回波,雷達收到回波便可發現目標?！稗D發”：來自應答器（Transponder），“識別器”，后者收到雷達信號后發射經過編碼的“應答波”被雷達所接收，從而發現目標?！肮逃休椛洹保簛碜跃哂泄逃休椛湓吹哪繕耍ㄈ顼w機、發動機、核爆炸、目標上無線電裝置等）雷達接收目標的固有輻射波而發現目標。Chapter1 BasicPrincipleofRadar現代雷達與電子計算機、圖象處理、數據處理、自動控制等技術結合，又具有自動信息處理功能及智能化顯示終端，可自動、迅速、準確地完成測量、顯示、控制和管理。Chapter1 BasicPrincipleofRadar1886-1888Hertz(Germany):realizedelectromagneticwaveoscillating,transmitting,receiving.1914(American):Echosounder－Proto-modelofradar.1922Marconi(Italy):Suggestedapracticableradarsystem.1930Blair:Pulseechomeasurement(range,direction)system－basicradar.Chapter1 BasicPrincipleofRadarRCACo.(American):Inventedairplane-carriedradar.(America):“NewYork”Cruiserequippedwithradar.AfterWWII:Asanavigationaidsdevelopedrapidly.China:Techniquemainlyfromdevelopedcountries.Modernradar/ARPA:Withcomputer,integratednavigationsystem(Loran,GPS,ECDIS,AIS),colourTVdisplayAutomaticbridgenavigationsystem.Chapter1 BasicPrincipleofRadarRadar/ARPA,ECDIS,GPS/DGPSanddataauto-pilotcombinedtogetherwillbefuturemajornavigationsystemChapter1 BasicPrincipleofRadar雷達發展歷程模擬信號處理數字信息處理計算機信息處理Chapter1 BasicPrincipleofRadar模擬信號處理20世紀90年代前，雷達設備采用電子管或晶體管，發射功率較大，回波信號經接收系統實時處理，直接顯示在徑向圓周掃描顯示器（平面位置顯示器，PlanPositionIndicator-PPI）優點：技術成熟，具有良好的探測的分辨目標的能力，接收信噪比高，抗干擾能力強，故障率低，目標圖像穩定清晰，操作簡單方便，因而被稱為駕駛員“眼睛”缺點：采用實時的模擬信號處理系統和徑向圓周掃描顯示器，熒光屏的顯示亮度和對比度受到限制，無法實現彩色顯示

Chapter1 BasicPrincipleofRadarChapter1 BasicPrincipleofRadar數字信號處理雷達設備進步采用數字處理技術采用高亮度光柵掃描顯示（TV顯示）實現ATT和ARPA功能Chapter1 BasicPrincipleofRadar計算機信息處理隨著傳感網技術、現代通信技術、信息處理技術和衛星定位技術的發展，雷達功能更加強大Chapter1 BasicPrincipleofRadarTheuseofradaratseaMarineradar:Centi-metricwavelengthpulsetransmittingnavigationalradarForourmajor:Theuseofradaratsea.Threemainapplications:?

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Equivalent12nmrange)Ring(6Total)HLIslandOwnshipRadarcannot“feel”thebacksideofatarget,therefortargetdistortionisinevitable.Chapter1 BasicPrincipleofRadarChapter1 BasicPrincipleofRadar雷達圖像特點雷達圖像不同于海圖，也不同于日常生活中的視覺圖像；雷達圖像與設備自身性能、大氣船舶條件、目標反射特性以及周圍環境變化有關；雷達探測到的回波圖像與真實目標相比，可能有較大的變形，表現在：P6Chapter1 BasicPrincipleofRadar1.RangemeasurementΔt:duringwhichradiowavetoandformthetarget,C:electromagneticwavetravelvelocityinfreespace.R=slantrange(antenna–aim)Chapter1 BasicPrincipleofRadarΔt:veryshot;beyondthecapabilityofanyconventionaltimemeasuringdevice;Electronicdevice——CRT.Averysmallspotoflight.Thespeedofthistravelcanbeaccuratelycontrolledatvalueswhichallowthespottotransitthescreeninaslittleasafewmicroseconds.Thetimetakenforthespottocrossthescreenisthesameasthetimetakenforaradarpulsetomakethetwo-wayjourneytoatargetatachosenrange.Chapter1 BasicPrincipleofRadarAnechoreturnfromatargetisusedtoproduceanincreaseinthebrillianceofthemovingspot.Whenthespothascompletedthetrace,thebrillianceisautomaticallyreducedtozeroandthespotfliesbacktotheorigintoawaittheincidenceofthenexttransmission.Chapter1 BasicPrincipleofRadarBearingmeasurementBywayofdirectional

antenna(Scanner,Aerial).Chapter1 BasicPrincipleofRadarChapter1 BasicPrincipleofRadarBearingmeasurementBywayofdirectionalantenna(Scanner,Aerial).Chapter1 BasicPrincipleofRadar1.2.2TheechoprincipleTheechoisneverasloudastheoriginalblast.Thechanceof