Moxa ANT-WSB-ANM-05 Manuel D’Utilisation

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9
Differentiating Between Wireless Technologies
1.4 WLAN vs. Proprietary 2.4GHz
Common usage of the WLAN limits its distance to under 100 meters. Now with Moxa’s advanced technologies, it is 
also possible to extend the distance up to 10 kilometers for multi-point connections or 20 kilometers for point-to-
point connections.
The IEEE 802.11 standard is designed for high-speed data transmission. However, it is also vulnerable to outside 
interferences. This is unacceptable for some industrial applications where the control elements are often involved. 
It is a basic control requirement that communication must not be interrupted. To meet this requirement, there are 
some proprietary 2.4GHz band wireless devices that use FHSS spread spectrum technologies to meet the needs 
for higher noise resistance. In summary, FHSS sacrifices throughputs and communication ranges for more stability.
Table: WLAN vs. Proprietary Wireless
Moxa
Banner
Frequency
2.4 GHz (ISM)
900 MHz  (license needed)
2.4 GHz (ISM)
Standard
IEEE 802.11
Proprietary
Proprietary
Spread Spectrum
DSSS / OFDM
*a FHSS
FHSS
Throughput
22 Mbps
115200 bps
115200 bps
Distance
10 km
> 10 km
3.2 km
Communication method
Point to multiple points
Point to point
Point to point
*a: FHSS utilizes frequency hopping to avoid signal interference. Bluetooth is one example that uses this 
technology. In the early days, IEEE 802.11 also used FHSS but has since adopted DSSS (Direct Sequence Spread 
Spectrum) out of security concerns. 802.11a, 801.11g, and 802.11n adopt OFDM to increase their resistance to 
external interferences.
About modulation and spread spectrum, please refer to Chapter 2.1
WWAN vs. WLAN vs. WPAN vs. Proprietary RF
Technologies
WWAN
WLAN
WPAN
Proprietary RF
Standard
GSM/GPRS/CDMA/
WCDMA/WiMax
IEEE802.11
Bluetooth/
ZigBee
No Standard
Connection 
Mode
Point to point (GSM)
WAN (GPRS/3G)
LAN (TCP/IP)
Point to point
Point to Point
Communication 
coverage
5 km to 30 km
100 m to 300 m
Approx. 10m
100 m to 100 
km
Security
High
High
Medium
Low (not 
standard)
Throughput
50 kbps to 100 Mbps
54Mbps (802.11a/g), 
600 Mbps (802.11n)
115200 bps
115200 bps to 
1 Mbps