Nera WILINK I System Manual page 112

4.8.4.3.1.3 Maximum Cell Radius
The Maximum Cell Radius is used to adapt various timing parameters of the MAC
to the time it takes a message to reach its destination. This time delay is
dependent upon the distance between the originating and receiving units. The
timing parameters should be adapted to the largest expected delay, which is
determined from the distance from the AU of the farthest SU served by it.
NOTE
For Non-Line-Of-Sight (NLOS) links using refractions, the cell distance should be higher than the
line-of-sight distance. Typically a 10% margin is a good estimate for the increase in distance due to
the NLOS operation.
The basic time element (symbol) used by the system is 68 microseconds. This
symbol size is translated to a round trip delay of approximately 20 km, or a cell
radius of 10 km. Thus, it is recommended to set the Maximum Cell Radius using
a resolution of 10 km: the actual timing of the system is the same for any cell
radius larger than N*10 km and smaller than or equal to (N+1)*10.
NOTE
An SU located at a distance larger than the Maximum Cell Radius will be rejected during the
network entry process.
The values range is from 10 to 110 km. Use 10 km increments (10, 20, ....110).
The default is 20 km.
4.8.4.3.2 Phy Parameters
The Phy menu enables viewing/updating the Bandwidth parameter:
4.8.4.3.2.1 Bandwidth
The frequency bandwidth used by the radio. A change in the Bandwidth
parameter will take effect only after resetting the AU.
The Admin Status of all Channels belonging to the same AU must be disabled to
enable a configuration change in the Bandwidth parameter.
The available options are:
1 – 1.75 MHz
2 – 3.5 MHz
The default is 3.5 MHz.
4.8.4.3.3 Multi Channel Parameters
Each AU can include up to 4 Channels. In the current release only AUs with 2
Channels are available. Each channel can be connected to an ODU. The Multi
Channel menu includes the following options:
WILINK I MODULAR BASE STATION SYSTEM MANUAL
AU Menu
101