When　the　angular-profile　tuning　method　is　used　for　the　detection　of　small　defects　in　a　pipe,　the　defect　is　considered　as　a　new　passive　guided　wave　source.　The　focusing　phenomenon　is　analyzed　by　intercepting　the　defect　reflected　waves　and　conversion　modes,　which　gives　the　information　of　the　angular-profile　for　the　passive　wave　source　fields.　Based　on　the　information,　the　time　delays　and　amplitude　factors　for　a　guided　wave　array　are　computed.　The　Finite　Element　Analysis　and　experimental　results　show　that　this　method　can　be　used　to　reduce　the　computation　efforts　and　also　to　cater　for　the　variations　of　the　pipe　parameters,　the　transducer　array　and　the　detection　frequency　during　the　detection　processing,　which　can　contribute　to　the　popularization　and　application　of　this　method.　©　2009　Journal　of　Mechanical　Engineering.