Installation Instructions

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SECTION 3
ANTENNA SYSTEMS ADJUSTMENTS PROCEDURE
Table of contents
1 NM 3522 6 elements antenna system adjustments - LLZ .....................................7
1.1 Mechanical alignment of antenna array .............................................................7
1.1.1 Right angle points with reference to runway center line .............................. 7
1.1.2 Spacing distance between LPDA’s..............................................................7
1.1.3 Vertical alignment of LPDA support masts ..................................................7
1.1.4 Azimuth alignment of LPDA’s ......................................................................7
1.2 Electrical measurements.................................................................................... 7
1.2.1 CSB and SBO cables ..................................................................................7
1.2.2 CSB/SBO phasing .......................................................................................8
1.2.3 Antenna cable lengths (Electrical phase equality).......................................8
1.2.4 Antenna pair phasing...................................................................................8
1.2.5 Phase and amplitude transfer measurement...............................................10
1.2.6 Antenna return loss......................................................................................11
1.3 Course sector width adjustment......................................................................... 11
1.3.1 DDM check of ADU O/P (output port)..........................................................12
1.3.2 DDM field check...........................................................................................13
1.4 Monitor combining unit (MCU) adjustments .......................................................13
1.4.1 Course Line .................................................................................................13
1.4.2 Course Sector.............................................................................................. 13
1.5 Near field monitor adjustments...........................................................................13
1.5.1 Mechanical alignment..................................................................................13
1.5.2 Final electrical position adjustment.............................................................. 13
1.6 DC-Loop adjustment and testing........................................................................14
1.6.1 DC-LOOP adjustment..................................................................................14
1.6.2 Antenna fault condition testing.....................................................................14
2 NM 3523B 12 Elements antenna system adjustments - LLZ (Single frequency)15
2.1 Mechanical alignments of antenna array............................................................15
2.1.1 Right angle points with reference to runway centre line .............................. 15
2.1.2 Spacing distance between LPDA’s..............................................................15
2.1.3 Vertical alignment of LPDA support masts ..................................................15
2.1.4 Azimuth alignment of LPDA’s ......................................................................15
2.2 Electrical measurements.................................................................................... 15
2.2.1 CSB and SBO cables ..................................................................................15
2.2.2 CSB/SBO phasing .......................................................................................16
2.2.3 Antenna cable lengths (Electrical phase equality).......................................16
2.2.4 Antenna pair phasing...................................................................................16
2.2.5 Phase and amplitude transfer measurement...............................................18
2.2.6 Antenna return loss......................................................................................18
2.3 Course sector adjustment ..................................................................................19
2.3.1 DDM check of ADU O/P ..............................................................................19
2.3.2 DDM field check...........................................................................................20
2.4 Monitor combining unit (MCU) adjustments .......................................................21
2.4.1 Course Line .................................................................................................21
2.4.2 Course Sector.............................................................................................. 21
2.5 Near field monitor adjustments...........................................................................21