RACOM RipEX 1.12.0, Руководство пользователя, Страница: 107 / 189

Note: CPFSK modulations have approx. 20% higher frequency deviation compared to CE, so
the receiver sensitivity for the same modulation (data rate) is approx. 1-2 dB better.
○ Narrow
Special settings for extra-restrictive regulations.
Note: In the 25 kHz channel spacing, the RipEX transmitted signal 16kHz bandwidth contains
99% of the total integrated power for transmitted spectrum according to ITU-R SM328 . This
setting is required for 25 kHz channel spacing by authorities in Czech Republic.
○ Unlimited
Full channel width used to achieve the maximum possible data rate.
• Modulation rate [kbps]
List box: possible values
Default = 20.83 | 4CPFSK
Possible values in list box are dependent on the Mode setting. The two highest rates for 25 and 50
kHz channel spacing are available only when the corresponding SW feature key is active (Either
the 166/83 kbps key or the Master key).
Higher Modulation rates provide higher data speeds but they also result in poorer receiver sensitivity,
i.e. reduced coverage range. Reliability of communication over a radio channel is always higher
with lower Modulation rates.
RF power [W]**
List box: possible values
Default = 5 W
The range of values in the list box is limited to 2 W for high Modulation rates. 10 W is available only
for lower Modulation rates (CPFSK) and only when the corresponding SW feature key is active.
Note: Max. RF power for RipEX-470 is 8 W. (Even if there was 10W in list box for fw ver. 1.3.x.x and
older)
FEC
List box: possible values
Default = Off
FEC (Forward Error Correction) is a very effective method to minimize radio channel impairments.
Basically the sender inserts some redundant data into its messages. This redundancy allows the re-
ceiver to detect and correct errors (to some extent). The improvement comes at the expense of the
user data rate. The lower the FEC ratio, the better the capability of error correction and the lower the
user data rate. The User data rate = Modulation rate x FEC ratio.
Optimization*
List box: On, Off
Default = Off
Optimization is applicable in Router mode for packets directed to Radio channel. It watches packets
on individual radio links and optimizes both the traffic to the counterpart of a link and the sharing of the
Radio channel capacity among the links.
On an individual link the optimizer supervises the traffic and it tries to join short packets when oppor-
tunity comes. However in case of heavy load on one link (e.g. FTP download) it splits the continuous
stream of packets and creates a window for the other links. To minimize the actual load, Zlib compression
(with LZ77 decimation and Huffman coding) and other sophisticated methods are used.
107 © RACOM s.r.o. – RipEX Radio modem & Router
Advanced Configuration