User's Manual

Exalt Installation and Management Guide
ExtendAir
®
(TDD) Series Direct Mount
000000-001 9
2011-08-26
Link Orientation and Synchronization
Link orientation refers to the Radio A and Radio B placement in your network. Link synchronization
refers to using external or internal timing to coordinate multiple links.
For every link, one end of the radio link must be configured as Radio A, while the other end is
configured as Radio B. In single-link systems, it does not matter which end of the system is mounted at
which end of the link, and there is typically no requirement for any link synchronization.
Link orientation and synchronization are more important for networks with site(s) where there is more
than one link of the same type or for sites using the same type of radio that are very close to each
another at one or both ends.
Configure collocated radio terminals for the same link orientation. That is, configure all radios at the
same location as Radio A or Radio B.
It can be advantageous to utilize link synchronization for collocated links. The radios allow the use of
an optional GPS synchronization kit. This synchronization controls the transmitter and receiver frame
timing so that collocated radios are transmitting at the same time and receiving at the same time. This
can substantially reduce the opportunity for self-interference. Without synchronization, collocated
radios may be transmitting and receiving at the same time, incurring near-end interference.
Radio A/B Configuration
Use the Exalt GUI to configure the radio terminals for Radio A and Radio B orientation. Since many
other parameters also need to be set, and the Exalt GUI is needed for these configurations, this is the
best way to completely configure the radio terminals.
Radios arrive from manufacture in default configuration, orientated as Radio B and configured as
shown in Table 1.
Note: Disable all T1/E1 ports if there are no T1/E1 interfaces connected. This shifts all available
throughput to the Ethernet interface.
Note: If a selected combination of the Link Distance, Frame Size, Bandwidth, and Mode
parameters cannot support all the desired T1 or E1 ports, the ports that cannot be supported are
automatically disabled. Priority is placed on the T1/E1 port number. That is, the first port to be
disabled, if necessary, is the highest port number, such as Port 4. See T1/E1 Configuration Pages
for more information.
Note: It is not always necessary to synchronize collocated radios. If antennas are substantially
separated or blocked from one another and/or frequency separation tuning is used, the
opportunity for near-end interference can be eliminated.
Note: When synchronization is required or desired, one GPS kit is required for each r-Series
radio link in the connected or collocated network.