Alvarion BreezeACCESS II, Системное руководство

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2-50
BreezeACCESS Version 4.5 Operations and Administration
Manual Revision: 1.0
Max. Hopping Sequence (Shift) (channels) = Number of hopping
frequencies-1.
The actual hopping sequences depend on the method used for defining
the basic hopping sequence: Standard Scrambling, Enhanced
Scrambling or Manual Sequence Definition. In Enhanced Scrambling
mode it depends also on the number of frequencies.
Enhanced Scrambling mode, 7 or more frequencies:
In this mode, the shift operation is performed on the channel indexes.
The actual hopping channel is calculated by increasing the indexes of
the basic hopping sequence by the value of the Hopping Sequence
(Shift). The sequence is cyclic, so that adding 1 to the highest index in
the sequence (Index=N where N is the number of channels in the
sequence) results in the first channel (Index=1).
Example: Enhanced Scrambling, N=8, Spanning Factor=3:
Table 2-5: Hopping Sequence (Shift) Implementation, Enhanced Scrambling,
N
=8,
Spanning Factor=3
For example, if the defined hopping frequencies are 2411, 2412, 2413,
2414, 2415, 2416, 2417 and, 2418, then the frequencies of the actual
hopping sequences are as shown in the following table:
Table 2-6: Actual Hopping sequences, Enhanced Scrambling
(N=8, Spanning Factor=3)
Hopping Sequence (Shift)) Actual Sequence Indexes
0 (basic sequence) 1, 4, 7, 2, 5, 8, 3, 6
1 2 , 5 , 8 , 3 , 6 , 1 , 4 , 7
2 3 , 6 , 1 , 4 , 7 , 2 , 5 , 8
3 4 , 7 , 2 , 5 , 8 , 3 , 6 , 1
4 5 , 8 , 3 , 6 , 1 , 4 , 7 , 2
5 6 , 1 , 4 , 7 , 2 , 5 , 8 , 3
6 7 , 2 , 5 , 8 , 3 , 6 , 1 , 4
7 8 , 3 , 6 , 1 , 4 , 7 , 2 , 5
Hopping
Sequence
(Shift)
Hop #1 Hop #2 Hop #3 Hop #4 Hop #5 Hop #6 Hop #7 Hop #8
0 2411 2414 2417 2412 2415 2418 2413 2416
1 2412 2415 2418 2413 2416 2411 2414 2417
2 2413 2416 2411 2414 2417 2412 2415 2418