PERBAIKAN SINYAL TERIMA GROUND PENETRATING RADAR (GPR) UNTUK PENDETEKSIAN OBJEK BAWAH TANAH BERBASIS A-SCAN PROCESSING (ENHANCEMENT OF GROUND PENETRATING RADAR (GPR) RECEIVED SIGNAL FOR UNDERGROUND OBJECT DETECTION BASED ON A-SCAN PROCCESSING) - Rizky Ismoyo Siahaan (Universitas Telkom, 2008)