User Manual

P B L Tunnels Loc 2 Units 1 & 2 + 800MHz BDA
Maintenance Handbook
H/book Number:-60-056100HBKM
Issue No:-1
Date:-13/02/2003
Page:-68 of 68
5.2.2 Crossband Couplers (07-004801 & 07-005705)
5.2.2.1 Description
The purpose of a crossband coupler is to either combine/split transmission signals from
different parts of the frequency spectrum.
The crossband coupler fitted here, is the means by which the separate UHF & GSM frequency
band signals are mixed to form a composite RF signal.
It basically comprises of a 3 port device, two filters, one a low pass the other a high pass, that
are then mixed and fed to a common output. The couplers are built into a machined aluminium
casing having a centre screening wall between the filter sections and lid secured by screws at
frequent intervals over its perimeter to obtain a tight seal and to ensure linearity and stability
of response.
5.2.2.2 Technical Specification (07-004801)
Part No: 07-004801
390-490MHz
Passband:
700-900MHz
No. Of i/p ports: 2
No. Of o/p ports: 1
Insertion loss: 0.5dB (typical)
>40dB 390-490MHz
Isolation:
>40dB 700-900MHz
Impedance: 50O
Connectors: SMA female
Power rating: 50Watts (CW)
5.2.2.3 Technical Specification
Passband 250 MHz
380 MHz
70-250 MHz
380-960 MHz
Power Rating 50 Watts (CW)
Number of Input ports
2
Number of Output ports
1
Insertion loss 0.5 dB
Isolation > 50 dB 70-250 MHz
> 50 dB 380-960 MHz
(15 dB typical return loss 500-960)
Impedance 50 O
Connectors SMA- female
All other modules in this unit are described elsewhere in this document.