User's Manual

Appendix B. Basic Parameters
Base Station Equipment Installation Manual 40 BreezeACCESS Series
•
Frequency Offset
– Displays the current offset of the Hopping Band from
the beginning of the available frequency range, and allows entry of a new
offset. The offset is measured in channels, where each channel is 2 MHz. For
example, in products operating in the 3.5a band (3.410-3.452 GHz uplink), a
Frequency Offset of 5 (10 MHz) will cause the hopping band to start at 3.420
GHz for the uplink and at 3.520 GHz for the downlink. The maximum value
of the Frequency Offset is determined by the overall available bandwidth and
the selected Hopping Band (Hopping Band should be selected before
selecting the Frequency Offset).
The default Frequency Offset is 0.
When setting this parameter, consider the following relationship:
Max. Frequency Offset (channels) = (Overall Bandwidth-Hopping Band)/2
.
For example, in products operating in the 3.5a band with an overall
bandwidth of 42 MHz, if the selected Hopping Band is 12 MHz then the
allowed range for Frequency Offset is from 0 to 15 channels.
Notes:
In Single Channel mode, using the minimum (0) and the maximum
values of the Frequency Offset parameter will result in transmitting at
the edges of the band without using any guard band.
The Frequency Offset parameter does not have any effect on the
Flexible Hopping mode.
•
Hopping Shift
– Displays the current Hopping Shift parameter and allows
entry of a new value. Available only in AUs. All the associated SUs learn
the value of the Hopping Shift parameter from the AU during the association
process. The Hopping Shift parameter is used to provide different operational
hopping sequences when several co-located Access Units use the same band
(and hence the same basic hopping sequence). This minimizes the cross
interference among these AUs and sallow for better spectrum utilization.
Each unit represents a shift of one channel between hopping sequences. The
allowed range depends on the defined band.
When setting this parameter, consider the following relationship.
Max. Hopping Shift (channels) = Number of hopping frequencies-1
.
The default Hopping Shift is 0. The minimum recommended shift between
two adjacent AUs is 2.