Handbook

PBL UHF1/1A 1 & 2 Air Interface
Maintenance Handbook
H/book Number:-60-055900HBKM
Issue No:-2
Date:-20/10/2003
Page:-
67 of 85
5.2 UHF 2 Air Interface (60-055902)
5.2.1 Bandpass Filter (02-013401) See section 5.1.1
5.2.2 4 Port Tx Hybrid Combiner (05-003019)
5.2.2.1 Description
The 3dB Hybrid Combiner used is a device for accurately matching two or more RF
signals to single or multiple ports, whilst maintaining an accurate 50Ω load to all
inputs/outputs and ensuring that the VSWR and insertion losses are kept to a minimum.
Any unused ports will be terminated with an appropriate 50Ω load. In UHF 2 this hybrid
is used to combine the signals from the channel selective modules (from both UHF 1 &
2) in the downlink direction for onward transmission by fibre, and similar signals for
both UHF 1 & 2 are combined before being further split into the uplink channel modules.
5.2.2.2 Technical Specification
PARAMETER SPECIFICATION
Frequency Range: ƒ
o
± 10% (50 – 500 MHz)
Bandwidth: ƒ
o
± 10%
Inputs: 2
Outputs: 2
Insertion Loss: <3.5 dB
Isolation between Input or Output ports: >27 dB
Return Loss (VSWR) – Input: 1.3:1
Return Loss (VSWR) – Output: 1.3:1
Impedance: 50 Ω
operation: -10°C to +55°C
Temperature Range
storage: -20°C to +70°C
MTBF: >180,000 hours
Power Rating – Splitter: Up to 150 Watts (load dependant)
Power Rating – Combiner: Available up to 100 Watts
Environmental: IP54
Connectors: ‘N’ female
Dimensions: 118 x 102 x 35 mm (including connectors)
Weight: 0.5 kg