Intro

I am Goran, and I am playing with LoRa for some time...

I decided to buy and build one lora gateway so people around my house can use it (that includes me)

I have done this succesfully and spread the word about magic LoRa in my makerspace Radiona.

Other members asked is it posible to test LoRa without spending days in car in front of my house.

Members asked!

Radiona delivers!!!

But first things first...

What is LoRa.

LoRa

LoRa is technology used for LPWAN Low Power Wide Area Network

LoRa is IP block that describes modulation LoRa PHY

Lora is Proprietary modulation :(

LoRa is using chirp spread spectrum
(helps to get signal from noise better).

A chirp is a signal in which the frequency increases (up-chirp)
or decreases (down-chirp) with time.

LoRa works great in a noisy environment

Long range
Great battery life

Low transmit power (25mW)
Consumption (40mA TX, 10mA RX)
In sleep, chip is using under 1uA

Main LoRa Advantages

Low data rate

Air time limits

Main LoRa Disadvantages

Nodes (or single chanel gateway)

SX Chips from Semtech for different frequencies
EU uses 868MHz Band SX1276(433Mhz option with SX1278)

Gateway SX1301/SX1308 for gateway

Can receive 8 bands at the same time
Has better sensitivity then node chips

SX1301 -40*C - great sensitivity

SX1308 0*C - less sensitive in receiving

Chips are SPI controlled

LoRaWAN

LoRaWAN is a media access control (MAC) protocol for wide area networks. It is designed to allow low-powered devices to communicate with Internet-connected applications over the long range wireless connections.

https://stackforce.github.io/LoRaMac-doc/group___l_o_r_a_m_a_c.html

868MHz has Airtime limits

868MHz is a license-free band :)

125kHz bandwidth

Check gr-LoRa on git

Time spendt on air depends of SF and message lenght

LoRaWAN Protocol is supporting 3 classes

Class A
Sends msg - opens RX1 - waits for msg - opens RX2 - waits for msg - go to sleep
Class B
Sends and receives in adjusted time slots
Class C
Sends msg - opens RX1 - waits for msg - opens RX2 - waits for msg

Sends back message on same frequency, message has arrived RX1, or on special frequency RX2

Gateway has same airtime limits as the node - ( downlink depends on band )

Two way for node to attach to a network

Two keys, one for network server and one for data (application)

OTAA
Handshaking
Device sends request
Gateway calculates the session key
Node calculates session keys
Note that no key is sent by node nor by gw
Gateway sends accept (settings) encrypted with new keys

ABP
Authorisation by personalisation
You just set the session key on both sides
(keys never change so it is less secure)

Gateway is just Forwarder just forwarding messages

NODE <> Network

Packet forwarder - runs on gateway

Network architecture

Complete opensource solution on your servers

Gateway bridge broker

Network server broker
Application server broker

https://www.loraserver.io/

or use TTN - https://www.thethingsnetwork.org/ v3 should be

easier to deploy on your servers

Remember LoRa is all about compromise

LoRa is not for a lot of data, and not for time-critical data

Think a byte, not Kilobyte!

TTNZagreb by radiona (SmartZG)

Radiona had two LoRa workshops for now:

Build your GW
All about nodes - mapping the city

Our newest gateway by: Prizma

Coverage of our gateways

Our LoRa distance records

Zagreb - Karlovac - 54.5km - SF8

Zagreb - Maribot - 74.2km - SF12

Use cases

- IRNAS has few great ones
- Count penguins
- power on - take pic - OpenCV count penguins - lora send no of penguins - power off
- Pit stop for turtles
- Trap for poachers
- Smart birdhouse
- Intrudes alarm in distant house - or boat...
- Public scale
- Pager
- GPS for pets
- Polution detector
- If something bad detected send a warning
- Agriculture
- Distant plant soil moisture

So many other

Warning:

Do not put your GW near a working chimney