Time Division Duplex Synchronization; Figure 1-13 Interference Between Two Odus On The Same Mast - Motorola PTP 48600 User Manual

User Guide: PTP 600 Series
NOTE

Time division duplex synchronization

The performance of any radio system is dependent on the level of electromagnetic
interference to which it is subjected. This is also true for the PTP 600 ODUs. In an
ideal environment, any individual ODU will only receive transmissions from the paired
ODU at the other end of the link. However, when multiple PTP 600 links are installed,
an ODU may also be subjected to interference from the transmission of an ODU which
is part of another link. The levels of interference become very significant when ODUs
are installed in close proximity, for example on the same mast. In this case, one ODU
may be transmitting a burst at the same time as an ODU sharing the same mast is
receiving a burst from its paired ODU. This is shown in
seen to be interfering with ODU C and vice versa. This can adversely affect link
performance.

Figure 1-13 Interference between two ODUs on the same mast

phn-0896_009v003
Feb 2010
On system installation or start-up, this extends the initial scan time of the
Master unit by 60 seconds. To address the requirement to provide aggregate
uniform loading of the spectrum across all devices, the channel selection
algorithm will choose a channel at random from a list of useable channels.
The channel selection algorithm is initiated at link initialization and when
radar interference is detected.
UNDER DEVELOPMENT
Wireless operation
Figure 1-13, where ODU A is
1-25