User Manual

Exalt Communications, Inc.
Exalt i-Series Installation and Management Guide
5000001 81
2007-06-25
• Current RSL is the measurement of the received signal level at the radio antenna port.
This is the measured level of the RF signal coming from the opposite end of the radio
link. The link was engineered to a specific RSL by the link design engineer, and this
RSL should be obtained during installation and remain relatively stable during the
operation of the link. RSL can and will vary as a result of weather changes and other
external sources, such as path obstructions. Once again, this variation was part of the
original design to achieve a certain level of performance over time. Bit errors occur
when the RSL falls to a level within roughly 3dB of the threshold specification. When
the RSL falls below the threshold specification, the link disconnects and will not
reconnect until the RSL is above the threshold specification. The behavior of RSL in
relation to other alarms or measurements and external events can be very helpful in
troubleshooting activities.
• Errored Seconds (ES) indicates the total number of seconds that occurred where there
was at least one bit error since the last time that the radio statistics counter was reset.
Generally, ES are not a significant concern, so long as they are not continuous or
above the anticipated performance based on the original link engineering goals. If ES
are continuous or at a high rate, this is normally an indication of poor link
performance due to poor RSL or interference, or severe impact by weather or other
environmental factors. However, similar to the performance factors previously listed,
ES can and will occur in any radio link. Once again, consult the link engineer to
determine the original design goals, and compare actual performance to these
expectations to determine if any improvements are necessary or if other problems
may be causing excessive ES.
Note: Unavailable Seconds do not register as ES. In other words, the
ES counter counts all seconds that are errored NOT INCLUDING the
seconds that were classified as unavailable. The total number of seconds
with errors or outages is the sum of ES and Unavailable Seconds.
• Unavailable Seconds (also called UAS) are similar to ES, but this counter keeps track
of every second where the bit error rate equals or exceeds 1x10
-3
, as well as any
seconds where there is a complete loss of radio communication, over the period since
the last counter reset. If Unavailable Seconds are continuous or at a high rate, this is
normally an indication of poor link performance due to poor RSL or interference, or
severe impact by weather or other environmental factors. However, similar to the
performance factors listed above, Unavailable Seconds can and do occur in any radio
link. Consult the link engineer to determine the original design goals, and compare
actual performance to these expectations to determine if any improvements are
necessary or if other problems may be causing excessive Unavailable Seconds.
• Minimum RSL indicates the worst (lowest) received signal level that occurred since
the last counter reset. It is helpful to know if the RSL dropped significantly from the
normal level, or has reached a level near or below threshold.
• Minimum RSL Timestamp indicates the date and time when the Minimum RSL
occurred. This is helpful for general troubleshooting, and especially comparing to
items in the event log or diagnostic charts from the same time period.