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2. System Description
© 2007 Moseley, Inc. All Rights Reserved.
602-14886-01, Rev. A
The upper RSL LED meter is calibrated to represent exactly 10 dB for each LED, going
from -95 dBm at the far left (red) to -15 dBm at the far right (green). The brightness of
from -95 dBm at the far left (red) to -15 dBm at the far right (green). The brightness of
each LED is modulated for levels between 0 to 10 dB such that the far left LED will be
fully extinguished at -95 dBm and the far right LED will be fully illuminated at -15 dBm.
fully extinguished at -95 dBm and the far right LED will be fully illuminated at -15 dBm.
When the RSL is in the red region (<-75 dBm) the signal level is approaching or has
reached threshold (depends on modulation type).
reached threshold (depends on modulation type).
The transmit LED indicates full power will all 8 LEDs illuminated to minimum power with 1
LED illuminated. For simplex applications the both rows indicate either RSL or transmit
LED illuminated. For simplex applications the both rows indicate either RSL or transmit
power.
2.5System Description
The overall Event-HD digital radio architecture consists of a single 1RU rack mount
Software Defined Indoor Unit
TM
(SDIDU
TM
) with a cable connecting to an Outdoor Unit
(ODU). The IF signal between the SDIDU and ODU operates at a relatively low frequency
compared with the RF signal allowing for extensive cable runs in excess of 250 m with
inexpensive coaxial cable with no degradation in radio performance.
inexpensive coaxial cable with no degradation in radio performance.
The Event-HD ODU is mounted to a fixed or telescoping antenna mast near the desired
antenna location providing a short cable run between ODU and antenna at the RF
antenna location providing a short cable run between ODU and antenna at the RF
frequency. This SDIDU /ODU architecture is advantageous when compared to a single
IDU (no ODU) with external mount antenna as operating at these RF frequencies from
the IDU rack to the antenna will result in significant signal degradation and require
IDU (no ODU) with external mount antenna as operating at these RF frequencies from
the IDU rack to the antenna will result in significant signal degradation and require
expensive low-loss coaxial cable or waveguide.