Alvarion BreezeACCESS 900 Manual de Instruções descarregar pdf (Página 181)

Menus and Parameters

2-51

BreezeACCESS Version 4.5 System Manual

The following formula can be used for calculating the actual hopping

sequence:

(j)={[P

(j)+S-1]mod(N)}+1

Where:

S=Hopping Sequence (Shift)

N=number of channels in the sequence (modulus)

(j)=Channel no. j in the basic sequence (shift=0)

(j)=Channel no. j in the actual sequence with Hopping Sequence

(Shift) S

Example: The basic hopping sequence is 1, 4, 7, 2, 5, 8, 3, 6 (Enhanced

Scrambling, N=8, Spanning Factor=3).

The actual hopping sequence for a Hopping Sequence (Shift) of 3 is:

(1)=[1+3-1]mod8+1=4

(2)=[4+3-1]mod8+1=7

(3)=[7+3-1]mod8+1=2

(4)=[2+3-1]mod8+1=5

(5)=[5+3-1]mod8+1=8

(6)=[8+3-1]mod8+1=3

(7)=[3+3-1]mod8+1=6

(8)=[6+3-1]mod8+1=1

The actual hopping sequence indexes are: 4, 7, 2, 5, 8, 3, 6, 1.

Standard and Manual Scrambling

In Standard and Manual Scrambling modes, the shift operation is

performed on the sequence elements. The basic sequence is shifted

cyclically according to the value of the Hopping Sequence (Shift)

parameter, so that element no. i in the actual sequence equals element

number i+s in the basic sequence, where s is the Hopping Sequence

(Shift). Thus, if the basic sequence is a, b, c, d, e, f then a shift of 1

results in the sequence b, c, d, e, f, a; a shift of 2 results in the sequence

c, d, e, f, a, b; and so on.

Example: Standard Scrambling, 6 frequencies (N=6):

3 2414 2417 2412 2415 2418 2413 2416 2411

4 2415 2418 2413 2416 2411 2414 2417 2412

5 2416 2411 2414 2417 2412 2415 2418 2413

6 2417 2412 2415 2418 2413 2416 2411 2414

7 2418 2413 2416 2411 2414 2417 2412 2415

1 2 ... 176 177 178 179 180 181 182 183 184 185 186 ... 323 324

Sem comentários

Alvarion BreezeACCESS 900 Manual de Instruções Página 181