User Manual

Axell Wireless Limited
Technical Literature
L.A. M.T.A. Remote Sites
Document Number 80-301401HBKM Issue No. 1 Date 13/06/2008 Page 84 of 148
4.5.5. Downlink Input Shelf 80-301407 Major Sub Components
section Component
Part
Component Part Description Qty Per
Assembly
4.5.5.1. 02-010701 Bandpass Filter 2
4.5.5.2. 02-010901 Bandpass Filter 1
4.5.5.3. 07-004815 Crossband Splitter/Coupler 550/800MHz 1
4.5.5.4. 07-005754 Crossband Splitter/Coupler VHF/UHF 1
4.5.5.5. 07-022005 30dB Bi-Directional Coupler 1
4.5.5.1. Bandpass Filter (02-010701)
The bandpass filters are multi-section designs with a bandwidth dependent upon the passband
frequencies, (both tuned to customer requirements). The response shape is basically Chebyshev with
a passband design ripple of 0.1dB. The filters are of combline design, and are carefully aligned during
manufacture in order to optimise the insertion loss, VSWR and intermodulation characteristics of the
unit. The tuned elements are silver-plated to reduce surface ohmic losses and maintain a good VSWR
figure and 50ȍ load at the input and output ports.
Being passive devices, the bandpass filters should have an extremely long operational life and require
no maintenance. Should a filter be suspect, it is usually most time efficient to replace the module
rather than attempt repair or re-tuning.
02-010701 Specification
PARAMETER SPECIFICATION
UHF Low Downlink 460.4 to 460.5 MHz Passband
Frequency
UHF Mid Downlink 482.5 to 483.8 MHz
UHF Low 0.1 MHz
Bandwidth
UHF Mid 1.3 MHz
Number of sections 5
Insertion loss 2.5 dB (typical)
VSWR better than 1.2:1
Connectors SMA
Power Handling 100W max
operation -20°C to +60°C Temperature
range
storage -40°C to +70°C
Weight 3 kg (typical)
4.5.5.2. Bandpass Filter 02-010901
Bandpass Filter 02-010901 is a multi-section design with a bandwidth dependent upon the passband
frequencies, (both tuned to customer requirements). The response shape is basically Chebyshev with
a passband design ripple of 0.1dB. The filters are of helical & combline design respectively, and are
carefully aligned during manufacture in order to optimise the insertion loss, VSWR and
intermodulation characteristics of the unit. The body and tuned elements are silver-plated to reduce
surface ohmic losses and maintain a good VSWR figure and 50ȍ load at the input and output ports.
Being passive devices, the bandpass filters should have an extremely long operational life and require
no maintenance.