User's Manual

Table Of Contents
Exalt Installation and Management Guide
EX-i Series (TDD) Digital Microwave Radios
10 206501-019
2016-05-24
System latency (delay)
The following generalizations can be made with regards to these factors:
The shorter the TDD frame size, the lower the latency
The shorter the link distance, the lower the latency, the higher the throughput
The longer the TDD frame size, the higher the throughput
The higher the bandwidth, the higher the capacity
The higher the mode, the higher the capacity
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.
Note: Disable all T1/E1/DS3 ports if there are no T1/E1/DS3 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 TDM ports, the ports that cannot be supported are
automatically disabled. Priority is placed on the DS3 port, and then the T1/E1 port number.
That is, the first port to be disabled, if necessary, is the highest T1/E1 port number, such as
Port 4 for the standard models, and Port 16 for -16 or -DS3 models (assuming that the DS3
and/or all 16 TDM interfaces are licensed for use). 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: The GPS sync feature is not available on all models. Contact your Exalt Wireless
representative for details.