Promax RANGER Neo 2, User Manual

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Chapter i: OPTICAL OPTION 282 October 2021
The 2.6 GHz LTE option expands the spectrum analyzer to the band 7 of LTE.
Band 7 is defined by an uplink band between 2.5 and 2.57 GHz and a downlink
band between 2.62 and 2.69 GHz. Band 7 of LTE is one of the most used globally
since it allows to transmit with greater speed but at a shorter distance and is
more exposed to suffer interference.
This expansion module is available for any unit (both for new equipment or to
upgrade equipment owned).
The selective meter consists, in first place, of a selective triple filter for 1310,
1490 and 1550 nm signals. The filter separates each wavelength and each one
leads to an independent circuit with a photosensor, which obtains the RF signal
that it carries. Next, a circuit measures the optical signal power received by the
photosensor. The RF signal obtained for each wavelength goes to a band switch.
The band switch receives a signal and converts it to a frequency within the RF
band (65 — 2150 MHz). In the case of a terrestrial/cable signal the signal is not
converted since that signal is within the RF range.
After the conversion, the RF signal output is connected to the analyzer input
connector and the measurement is performed in the usual way to an RF signal.
In the conversion, bear in mind that for every unit of optical attenuation
(one dB), occurs two dBs of power loss in RF. As an example, every 3 dB of
optical attenuation for each splitter are equivalent to 6 dB of power loss for RF.
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Description
The optical function of this module allows the user to certify a
telecommunication installation by calibrating the signals at the installation and
then measuring them in each of the user access points.
The optical module can measure simultaneously and in a selective way the three
wavelengths used in optical fibre (1310, 1490 and 1550 nm). It has a selective
receiver with a filter for each band that makes a real and very stable
Optical fiber
S
C
A
N
i.2 Selective Optical Power Meter
i.2.1 Description
i.2.2 Optical Fibre Test