User Manual

Exalt Installation and Management Guide
ExtendAir (TDD) Series Digital Microwave Radios
203591-011 15
2013-02-22
Figure 7 GPS Sync for more than one collocated radios
At the far end of a synchronized link, if there are additional links to synchronize, use the Sync Out port
of the Radio B to drive synchronization to the collocated radios. If there is only one additional radio,
connect a cable from Sync Out to the Sync In port of the next radio, which should be configured as
Radio A. Set this radio in the chain to Sync Recipient, as shown in Figure 8. If more than one radio is
located at the secondary location, to drive synchronization for multiple Radio A terminals connect a
ExaltSync Collocation Kit driven from the Radio B Sync Out port.
Figure 8 Synchronization for radios in a chain
Offset Timing
For GPS implementations, manual control of offset timing is also allowed. This provides a means to
delay the synchronization signal using a user-defined offset. This is helpful when Exalt radios are near
other devices operating in the same frequency band that also use a timing source, such as GPS. The
timing source to the Exalt radios can be adjusted to match the other radio system timing source
mechanism.
Offset timing can also optimize timing intervals for repeaters and backbones. As the distance of each
link results in a unique factor for speed-of-light transmission of the radio signal, a subsequent radio can
be delayed in timing so that the overall synchronization of radios is precisely maintained.
Offset timing can be adjusted in 1-ms intervals, from zero to the radio’s frame length setting. For
example, if using a 2-ms frame length, the offset timing can be set from zero up to 1999 ms.