Libelium Waspmote, Техническое руководство

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-72- v6.3
802.15.4/ZigBee
8.3. XBee - 868
Module Frequency Transmission Power Sensitivity Channels Distance
XBee 868 869,4 – 869,65MHz 315mW -112dBm 1 12km
Figure: XBee 868
Note
: The XBee 868 MHz module is provided with 4.5dBi antenna, which enables maximum range.
The frequency used is the 869MHz band (Europe), using 1 single channel. The use of this module is only allowed in Europe. In
the chapter “Certifications”, more information can be obtained about the
Certifications
.
Figure: Channel frequency on 869MHz
Encryption is provided through the
AES 128b algorithm
. Specifically through the type
AES-CTR
. In this case the Frame Counter
field has a unique ID and encrypts all the information contained in the
Payload
field which is the place in the link layer frame
where the data to be sent is stored.
The way in which the libraries have been developed for module programming means that encryption activation is as simple as
running the initialization function and giving it a key to use in the encryption.
{
xbee868.setEncryptionMode(1);
xbee868.setLinkKey(key);
}
The classic topology for this type of network is a star topology, as the nodes can establish point to point connections with
brother nodes through the use of the MAC address.