What is Lora

industry 4.0

Lora

LoRa is a spread spectrum wireless technology, developed by Semtech Corporation. It has been developed to allow long distance transmission of low rate data. The low rate data is collected by remote field sensors and actuators, and is used for Internet of Things and M2M applications. Lora uses the 868 Mhz unlicensed radio spectrum, in what is known as the ISM (Industrial, Scientific and Medical) bands to wirelessly facilitate low power, wide area data communication between the remote sensors and gateway devices, which connect to the Internet, or other network.

How to Build a Lorawan Gateway

industry 4.0

What is  Lorawan

First of all, what is Lorawan.  It is a wireless technology that allows small amounts of data to be sent between a remote sensor (such as a river level detector), and the Internet.

Lorawan technology is very efficient at sending the sensor data over long distances, whilst consuming very little power. This means that a the sensor devices can be battery powered, whilst the batteries last for years.

What is a Gateway then

A Lorawan Gateway is the device that receives the wireless signals containing data, that has been transmitted (using Lora wireless technology) from the remote sensors (river level monitoring, air quality etc).

Once the  Gateway has received the  wirelessly transmitted data, the gateway forwards the data onto the Internet.

Gateway connection to the Internet can be via a variety of means, such as Wifi, Ethernet, 3G, 4G, 5G etc.

Building the Gateway

For beginners to building their own gateway, I would recommend joining, or founding a local Things Network .

The Lorawan Gateway that I am going to describe here, is designed to operate on the Things Network, however other lora networks can easily be installed.

The main components that you will need are:-

1) A Concentrator board from IMST of Germany. The Concentrator board is the wireless communications part of the system, responsible for receiving the wireless data signals, from the remote environmental sensors (Air quality sensors etc).

2) A small computer to store the software that controls the Concentrator board. We are going to use the UK designed Raspberry PI 3.

A Micro SD Card, for holding the software used by the Raspberry PI.  A small 4 GB card is fine.

3) A suitable Antenna (or Aerial), with pigtail connecting cable.

4) A suitable 2 Amp rated power supply, with a micro USB connector.

5)  7 Female to Female connecting leads, suitable for raspberry PI.

4) A suitable case, to house the components.

 

The first thing I need to make you aware of is the risk of static electricity, to your IMST ic880a Concentrator and Raspberry PI.

Static can damage the sensitive electronic components, therefore it is advisable to take precautions, such as not touching the board components, and wearing an anti static wrist strap.

The first thing you need to do is to format the micro SD card, that will be fitted to the raspberry PI, to hold the gateway software.

The SD card association has a free piece of software, for Windows PC and Mac, to do this. My card was already formatted, so I skipped this step.

The next step is to burn the actual software that will power your gateway, onto the Raspberry PI.

To do this, I used https://etcher.io/    

I first installed Etcher onto my  linux desktop computer. As most people use Windows PC, or Mac, you will need to find a suitable alternative to Etcher.

I also downloaded the operating system needed to run the Raspberry Pi, which is called Raspbian Stretch Lite , onto my desktop PC.

Put your micro SD card into your computers micro SD card reader. If your computer (like mine) does not have a card reader, then external USB plug in ones can be purchased cheaply (I got mine from my local Asda supermarket for £6).

Fire up Etcher, or whatever card  burning software you prefer, and select the copy of Raspbian Stretch Lite , that you previously downloaded to your PC.

Follow the instructions, and burn the operating system software onto the micro SD card.

Once you have successfully burned your Raspbian Stretch Lite, onto your SD card, insert it into the Raspberry Pi (the slot is on the underside of the Pi).

The next thing to do is to connect your Raspberry Pi to a suitable monitor (I used a TV, that had a HDMI connection), and also connect a USB keyboard, power supply, and mouse.

The power supply should be 5 Volts DC, and Raspberry Pi power supplies are widely available. I used a USB phone charger, with 5 Volts output, and a current rating of 2000mA.

Boot up your Raspberry Pi (connect the power), and you will see lots of computer code scrolling across your screen (if you have done everything successfully, so far).

When the Raspberry Pi asks you for a user name and password, use the following default ones (the  bit after the  ‘ : ‘ ).

Username: Pi

Password: Raspberry

After you have successfully logged in, type:

 sudo raspi-config

Numbered options will now hopefully be on your monitor screen.

Select [5] Interfacing Options, and then P4 SPI

Then select [7] Advanced Options , and then [A1] Expand Filesystem.

You now need to exit the raspi-config utility, either by hitting the ‘CTRL’  and  ‘X’ keys, or by typing sudo reboot

Next you are going to Configure the locales and time zone.

Type this in, to set the locales, and follow instruction.

sudo dpkg-reconfigure locales

Next, type this in to set time zone.

sudo dpkg-reconfigure tzdata

The next stage is to update the raspberry Pi software, do this by typing:

sudo apt-get update

Then install any upgrades to the operating system software, by typing sudo apt-get upgrade

Next we are going to install Git , which is needed to be able to download the Things Network software from Github.

Type:

sudo apt-get install git

The next step is to create a user called TTN (the things network).  This user will eventually replace the default raspberry pi user, which we will delete.

sudo adduser ttn

Then:    sudo adduser ttn sudo

Logout, by typing logout

Once you have logged out, log back in using the user name and password that you have just set up, when you added a user.

You can now delete the default Raspberry Pi user, by typing

sudo userdel -rf pi

 

Set the WIFI  SSID and password details, which can be found on the back of your home router / Hub (usually).

To set the WIFI details type

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf 

Once you have typed in the above text, you should see some code on the screen. Add the following to the end of the existing code, making sure that you enter your SSID and password details, in place of the shown text.

network=

{
ssid="The_SSID_of_your_wifi"
psk="Your_wifi_password"

}

Now we are going to clone the installer from Github. This will download the software which runs the gateway, from the Github repository.  Type each of the following three code lines into your Pi, one at a time, hitting the return key after each line of code.

  git clone -b spi https://github.com/ttn-zh/ic880a-gateway.git ~/ic880a-gateway
  cd ~/ic880a-gateway
  sudo ./install.sh spi

Identifying the Gateway

The software will give the gateway the default name of ttn-gateway.

This however may need to be changed, to prevent issues with other Things Network Gateways within wireless range.

Wiring it Up

The next step is to connect the Concentrator board, to the Raspberry Pi, and also connect the antenna.

The components including the antenna should be mounted in a protective box,  and the antenna connected to the Concentrator board.

It is very important that the Concentrator board is not powered up, with no suitable antenna connected, of damage could occur to the board.

Once the antenna is connected, then the next step is to connect the Concentrator to the Raspberry Pi.

Connect using female to female connecting wires, as follows:

iC880a Concentrator pin Description RPi physical pin
21 Supply 5V 2
22 GND 6
13 Reset 22
14 SPI CLK 23
15 MISO 21
16 MOSI 19
17 NSS 24

IMPORTANT DISCLAIMER:

It is important that you identify the correct pins, by referring to the manufactures data sheets (Both IMST & Raspberry Pi).

We accept no liability for loss or damage caused, by following these information only instructions.

For help, as to which pin is which on the Concentrator and Raspberry Pi boards, why not get in touch.

I also offer workshop training, where I can train your students to build their own Lorawan Gateways.

@acraigmiles

www.craigmiles.co.uk

Craig Miles (C) 2018 , all images and content, unless stated separately.

Fuses in Radio Equipment power Supplies

taxi radio faults

The importance of fuses in radio equipment power supplies

A safe two-way radio equipment installation requires the ability to quickly disconnect the supply to the equipment, if a fault develops. Fuses are a cost effective solution, for equipment safety.

What are Electrical Fuses

Fuses are devices that protect equipment installations, from excess electrical current.

Excess current is caused by a fault in the equipment, or system wiring, and can cause equipment damage, or even fire.

The fuse works by ‘blowing’ if a certain current through it is exceeded. When the fuse ‘blows’, the electrical current ceases to flow, due to a physical break inside the fuse, preventing current flow through it.

Types of Fuses

Electrical fuses come in a variety of package types, and current ratings.

For example, package types include ‘cartridge’ and ‘blade’ designs.

Fuses are also made to blow at different current thresholds, so can be matched to the piece of equipment it is connected to.

There are also fuse types known as ‘slow blow’ fuses.

Slow Blow fuses are designed not to blow due to a short spike in electrical current. Short spikes can be caused by surge currents, which is a very temporary increase in current, when a piece of equipment is started.

Importance of correct Fuses

Fitting an incorrect fuse can either reduce safety, or reliability.

For example, if a fuse is fitted that has too high a current blow rating, then if a fault develops with the equipment, the electricity will find another weak point in the system. This weak point could be the radio equipment itself, and the excess current could damage it.

On the other hand, fitting a fuse that has too small a current rating will reduce system reliability.

This is because the current being drawn by the radio equipment is more than the fuse can cope with, and therefore will blow.

Two way radio equipment, draws less current when receiving, than when it is transmitting. Therefore the fitting of a too small fuse, may not become apparent, until the two way radio transmits.

Always refer to the manufacturers equipment specifications to understand the maximum current that the equipment will draw, and select a fuse slightly larger.

If no manufacturers data is available, then using an Ammeter in series with the DC supply, can determine the current drawn. Remember however, to also test on transmit, and with maximum transmit power selected (if an option).

(c) 2018 Craig Miles / Yesway Ltd.

Lincoln Things Network sponsored by Yesway

sensors

Lincoln Things Network  Sponsorship

What is the Things Network

The Things Network is a worldwide crowd funded Internet Of Things Network, which started in Amsterdam.

It consists of sensors, such as air quality sensors that transmit data wirelessly via ‘Gateway’ devices to the Internet Cloud.

It is rapidly expanding around the world, including the UK.

Why do we need this network?

The world is undergoing rapid change in the world of work, and it has been predicted that many jobs will become automated in the coming years.

The Internet Of Things, or IOT for short, along with Virtual Reality & 3D Printing  is part of this new industrial revolution.

It is therefore vitally important that we educate the current and future generations quickly, so we don’t get left behind as a nation.

The Things Network helps educate people, and lets businesses cost effectively develop new IOT products.

Where DoesThe Lincoln Network Cover

The Things Network is based on a wireless technology called LoraWAN.

As with all wireless technologies LoraWAN, which the Things Network runs on is range limited.

One of the great features of LoraWAN technology is that the signal can travel a long distance, using low power.

However as with all wireless technologies, buildings and natural objects in ‘line of sight’, will reduce the signal range.

The Things Network uses devices called ‘Gateways’ to receive the signals transmitted wirelessly from the remote sensors, and puts the data onto the web.

Currently the Lincoln Things Network has planned to install one Gateway near central Lincoln.

This should cover a large area of the City of Lincoln, but other additional Gateways may well be necessary, due to objects, reducing the signal coverage.

When will the Network be live

The components for the first Gateway device for the Lincoln Network has been ordered, and the gateway is currently being constructed.

As the Things Network is essentially a voluntary community effort, we welcome help from schools and local businesses.

Please get involved, as any help is appreciated.

Who is behind the Lincoln things Network

The Lincoln Things Network was initiated by Craig Miles, who can be contacted via the community page at https://www.thethingsnetwork.org/community/lincoln/

Alternatively he can be contacted via his personal website at  www.craigmiles.co.uk

Sledging radios

Hytera PD405 video review

Going of sledging or skiing this year?

Depending on where you are going will make a difference.

For example, if you are planning a commercial event in Aviemore, in the Scottish Highlands for example, then a licenced VHF handheld might be the best option.

These licenced hand-held radios typically produce 5 Watts of RF power output, and allow reliable communication over a wide countryside area.

These radios can be hired or bought from Yesway.

The licenced radio solution however does have some drawbacks for sledging or skiing events.

The main disadvantage is that licenced radios are only licenced for your particular country, in most readers circumstances, the United Kingdom.

Therefore if you are an event company that organises events in more than one country, you might want to consider PMR446.

PMR446 is a licence free handheld radio standard, that allows usage in the European Union & EEA countries.

Therefore a sledger or skier could move between european countries without the licencing headaches of having to apply in each country for a licence.

The downside is range. PMR446 handheld radios operate at UHF (Ultra High Frequency) frequencies. These generally perform less well than VHF (Very High Frequency), in terms of maximum communication range.

Another important downside of PMR446, is that the RF (Radio Frequency) transmit power output is only 1/2 Watt (0.5 Watt). This compares with typically 5 Watts (0.5 Watts) for a licenced handheld radio.

Whilst having 10 times the power, does not mean the signal traveling 10 times further, it does give it more ‘punch’. This ‘punch’  helps get the signal through obstacles, such as trees, which ‘attenuate’ the signal.