Libelium Waspmote, Техническое руководство

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LoRaWAN
9. LoRaWAN
LoRaWAN is a Low Power Wide Area Network (LPWAN) specification intended for wireless battery operated devices in regional,
national or global network. LoRaWAN target key requirements of Internet of things such as secure bi-directional communication,
mobility and localization services. This standard will provide seamless interoperability among smart Things without the need
of complex local installations and gives back the freedom to the user, developer, businesses enabling the role out of Internet of
Things.
LoRaWAN network architecture is typically laid out in a star-of-stars topology in which gateways is a transparent bridge relaying
messages between end-devices and a central network server in the back-end. Gateways are connected to the network server
via standard IP connections while end-devices use single-hop wireless communication to one or many gateways.
Communication between end-devices and gateways is spread out on different frequency channels and data rates. The selection
of the data rate is a trade-off between communication range and message duration. Due to the spread spectrum technology,
communications with different data rates do not interfere with each other and create a set of “virtual” channels increasing the
capacity of the gateway. To maximize both battery life of the end-devices and overall network capacity, the LoRaWAN network
server is managing the data rate and RF output for each end-device individually by means of an adaptive data rate (ADR)
scheme.
Figure: LoRaWAN module with normal antenna Figure: LoRaWAN module with 0 dBi antenna