Intelligent Dynamic Frequency Selection; Radar Avoidance - Motorola PTP 48600 User Manual

Wireless operation

Intelligent dynamic frequency selection

The PTP 600 series uses an interference mitigation technique known as Intelligent
Dynamic Frequency Selection (i-DFS). Both the PTP 600 Master and PTP 600 Slave
continually monitor for interference on all channels and then select the best frequency
of operation. This is a dynamic process where the PTP 600 can continually move
channels in response to changes in interference. Two modes of operation are available,
one where the two link directions are forced to select the same frequency. This is
determined by the Master. The second mode is where the frequency of operation can
be determined independently for each direction. This is a key feature which enables
the PTP 600 to operate successfully in areas where other radio equipments are
operating within the same band.
NOTE

Radar avoidance

Similar to current description except that we need some words to cover the option of
hopping channels in response to interference other than Radar.
Radar avoidance requires that equipment used in the region:
•
Detects interference from other systems and avoids co-channel operation with
these systems, notably radar systems.
•
Provides a uniform loading of the spectrum across all devices, that is, fixed
frequency operation is not allowed.
To address the primary aims, the spectrum management algorithm implements a
radar detection function which looks for impulsive interference on the operating
channel only. If impulsive interference is detected, spectrum management will mark
the current operating channel as having detected radar (unavailable channel) and
initiate a channel hop to an available channel. The previous operating channel will
remain in the unavailable state for thirty minutes after the last impulsive interference
pulse was detected. After the thirty minutes have expired the channel will be returned
to the usable channel pool.
The equipment can only transmit on available channels, of which there are none at
initial power up. The radar detection algorithm will always scan a usable channel for
60 seconds for radar interference before making the channel an available channel.
This compulsory channel scan will mean that there is a 60 seconds service outage
every time radar is detected and that the installation time is extended by 60 seconds
even if there is found to be no radar on the channel.
1-24
i-DFS is not available in the 2.5 GHz band.
UNDER DEVELOPMENT
Chapter 1 Product description
phn-0896_009v003
Feb 2010