User's Manual

FreeWave Technologies Spread Spectrum Transceiver User Manual

900 MHz and 2.4 GHz

V5.0S

2.4GHz

The Frequency Key for the FreeWave Technologies 2.4GHz transceivers offers

the ability to select more than just a different pseudo random hop table, but also

the portion of the band which the transceiver will use. Because this feature offers

the ability to select which portion of the spectrum will be used it is critical that all

radios in a link, whether point to point or point to multipoint, use the same

selections.

Frequency Key

Selections 0-E provide 15 different pseudo random hop tables, similar to the 900

MHz transceiver.

Selection F allows the user to set the Hop Table parameters. The user is then

presented with 3 additional choices

Selection 0 allows the user to determine which portion of the band to use:

Selection Band Used

0 Entire band, 2.400 - 2.4835 GHz

1 Entire band, but offset frequencies from selection 0

2 Lower 1/3

of band

3 Middle of band

4 Upper 1/3

of band

5 2 outer 1/3

rds

of band, avoids the middle

Thus, 2 networks could be set up side by side using the entire band without

collisions by setting one network up with selection 0 and the second network with

selection 1.

Selection 1 allows the user to set the size (number of frequencies) of the hop table

to use. The range available is from a minimum of 50 to a maximum of 80.

Selection 2 allows the user to select a frequency offset, whereby the frequencies

used are offset by 115.2 KHz from other frequency selections in the same portion

of the band. For example, if 2 networks are operating side by side in the lower

1/3

of the band using 50 frequencies, with one set to Frequency Offset of 0 and

the other to Frequency Offset of 1, the frequencies used in the different hopping

patterns will be offset by 115.2 KHz

Table 9: 2.4 GHz Frequency Band

Selections Available