User Manual

Exalt Installation and Management Guide
ExtendAir (TDD) Series Digital Microwave Radios
203591-011 51
2013-02-22
– Do not adjust the Radio Transmit Power parameter to a value higher than is legally allowed.
– Do not adjust the Radio Transmit Power parameter lower than the link budget and fade margin
can afford.
• Set the Bandwidth (MHz) parameter to the designed level. The value of this is determined in the
design/engineering stage. The Bandwidth parameter must also match at both ends of the link. In
conjunction with the Mode parameter, the Bandwidth parameter directly relates to the capacity,
latency, and the number of TDM circuits supported. The transmitter and receiver bandwidth are
modified using this parameter, making it critical that it be set with respect to the local RF noise and
interference profile, and/or in relation to any multi-link network design.
• Set the Mode parameter to the designed selection. The value of this setting is determined in the
design/engineering stage. The Mode parameter must match at both ends of the link. In conjunction
with the Bandwidth parameter, the Mode parameter setting directly relates to the capacity of the
system, as well as critical RF parameters, including receiver threshold, carrier-to-interference
ratio, and in some cases, maximum radio transmit power.
• Set the RF Frequency (GHz) parameter to the designed point. The value of this setting is
determined in the design/engineering stage. RF Frequency must match at both ends of the link. It
may be critical to set RF Frequency with respect to the local RF noise and interference profiles,
and/or in relation to any multi-link network design.
Note: Changing Radio Transmit Power may temporarily interrupt traffic. Small changes
in output power do not normally interrupt traffic, but larger changes may.
Note: The link may be lost and unrecoverable through GUI control. If the link is lost due to
reduction of Radio Transmit Power, travel to the radio location(s) may be required to reset the
value.
Note: Changing Bandwidth will temporarily interrupt traffic. The Bandwidth
parameter must match at each end. Adjust the far-end radio first, and then the near-end
radio. Changing Bandwidth changes the radio’s threshold. A narrower bandwidth has better
threshold performance and improved interference immunity, therefore if changing to a wider
bandwidth, there is an opportunity that the link may be lost and unrecoverable through GUI
control. Check the available fade margin and interference profile to determine if the impact to
threshold and increased bandwidth is acceptable to maintain the link and the desired
performance. If the link is lost due to increasing the Bandwidth parameter, travel to the radio
location(s) may be required to reset the value.
Note: Changing Mode will temporarily interrupt traffic. The Mode setting must match
at each end. Adjust the far-end radio first, and then the near-end radio. Changing Mode
changes the radio’s threshold, carrier-to-interference ratio, and also may have impact on the
Radio Transmit Power. A lower mode has better threshold performance and carrier-to-
interference ratio, and in some cases, higher output power, therefore if changing to a higher
mode (for example, from Mode 1 to Mode 2), there is an opportunity that the link may be
lost and unrecoverable through GUI control. Check the available fade margin and
interference profile, and determine if the impact to RF performance is sufficient to maintain
the link and desired performance. If the link is lost due to increasing the Mode parameter,
travel to the radio location(s) may be required to reset the value.