# Lopy-Lopy Communication Distance is too short !!!

• Hi Guys,
I was setting up a Lopy in my Home with External Antenna (Typically placed from Second Floor Window - Living in Chennai City in India) and one in my Car with an External Antenna trying the below configuration's on the both the Lopy

`lora = LoRa(mode=LoRa.LORA, frequency=868100000, power_mode=LoRa.ALWAYS_ON, tx_power=14, bandwidth=LoRa.BW_125KHZ, sf=12, preamble=8, coding_rate=LoRa.CODING_4_8, tx_iq=False, rx_iq=False)`

I was only able to recieve the msg hardly 150 meters.

How can i increase the distance of the Lopy atleast to work for a Mile ?

Thanks & regards,
MK HB

• @titi974 so last test was with sf7, we did it again with sf12 and managed to get 550 meters this time.

• Here in Paris on a very crowded street today (Champs-Elysées), we managed to get 300 meters.

• @mkharibalaji Did you pursue your car tracking idea further?

• @constantinos
I have already tried the configurations - nothing fruitful.

@Clemens
Range depends on the kind of inteference you have in your street,I have literally 3 different companies cell phone towers within 1 KM range around my area and this is quite obvious in most of the cities in India.
I tested it in a straight road with minimal interferences and able to get it around 400m.
But if we are to use it in a Metro/Cosmo Politan citiy with high interference, then we need to place the base station/reciever with multi channel in a high raise building with a good Antenna covering a range around 3 miles
Now the Challenge is whether the same Lora Chip with single Channel Gateway (Lopy) is capable of doing atleast the minimal coverage is what i am testing.
From the test,my simple inference is that Lora really works well in remote areas where there is little or no interference,so i dropped the asset tracking usecase of Lopy-Lopy where i am much disappointed.

You may find the following useful

Mode of LoRa
medium range: bandwidth=LoRa.BW_250KHZ,coding_rate=LoRa.CODING_4_5,sf=7
fast short range: bandwidth=LoRa.BW_500KHZ,coding_rate=LoRa.CODING_4_5,sf=7
slow long range: bandwidth=LoRa.BW_125KHZ,coding_rate=LoRa.CODING_4_8,sf=9
very slow long range: bandwidth=LoRa.BW_125KHZ,coding_rate=LoRa.CODING_4_8,sf=12

• I used a pair of LoPys with the "LoRa/Sigfox Antennen-Kit" http://www.exp-tech.de/lora-sigfox-antenna-kit . and `frequency=868000000, tx_power=14, bandwidth=LoRa.BW_125KHZ, sf=7` I reached around 450 m in the same street without line-of-sight. I think you will get no more distance with obstacles in between.

• @mkharibalaji
I did not test maximum distance yet, but it was able to send data through 6 concrete floors.
Before I tried LoRaWAN mode and connected to community network gateway over 5km away.

• @jmarcelino
I tried all the frequencies that you suggested but nothing worked out.

@danielm
That's interesting !. What is the distance between your lopy gateway and sensor that your able to send/recieve data ?

• So in the end it seems that if both sensor and gateway are on releases up to 1.6.3.b1 or 1.6.4b1 and newer the communication works well. I am now running both on 1.6.7.b1.

In 1.6.4.b1 following change was implemented:
esp32: Enable all spreading factors and bandwidths supported by the SX1272.
Maybe this is the reason for incompatibility between some (different) versions.

• I have gateway - sensor system based on LoPy. Until yesterday I was using releases from february. Yesterday I performed upgrade of both gateway and sensor and to my surprise LoRa message (16 Bytes) made it to the gateway only rarely. So I started downgrading the firmware incrementaly and found out that last release on which the communication works well is 1.6.3.b1. Not sure what is happening, will do more testing today.

• @jmarcelino
I will defenitely try and let you know today as i started with 865800000.

@livius
The Windowsill is made of concrete which contains a small iron grid and i hope it doesn't affect that much.

• I Placed it on the Windowsill

Is Windowsill metal? If yes i do not suppose it is good place.

• @mkharibalaji

Can you try other frequencies?

For example 865400000 , 865600000 , 865800000 ... 866800000

The frequency you're using isn't actually allowed in India, you need to stay within 865 MHz – 867 MHz. Check http://www.ensembletech.in/lora-frequency-bands-india/

• @jmarcelino
Yes,off course it's connected next to the LED

• @mkharibalaji
Just checking but is the antenna attached to the correct connector? Should be the one next to the LED.

• @livius
The Antenna that shipped along with my Lopy.
I Placed it on the Windowsill
In the car I kept it near my Gear where i plugged it to the USB and started moving in my Car from my Home.
There are quite a number of buildings and other Cell Phone Towers near my Home and obviously DTH Antenna's on top every Home.

``````        @livius - I am defenitely aware of the above said factor's & the line of sight but how to apply Lora in densely populated cities with quite a lot of inteference ?
I thought of tracking my Car within a particular range within the city atleast 2-3 Miles which can't be always in the line of Sight....
``````

Thanks & regards,
MK HB

• @mkharibalaji
This as always depend.
What kind of antenna?
Where do you place it? On windowsill? Or you hung it up somwhere?

Is something between car and window? Some buildings? Other near antennas in the area?

• I tried the below Config's

Mode of LoRa
medium range: bandwidth=LoRa.BW_250KHZ,coding_rate=LoRa.CODING_4_5,sf=7
fast short range: bandwidth=LoRa.BW_500KHZ,coding_rate=LoRa.CODING_4_5,sf=7
slow long range: bandwidth=LoRa.BW_125KHZ,coding_rate=LoRa.CODING_4_8,sf=9
very slow long range: bandwidth=LoRa.BW_125KHZ,coding_rate=LoRa.CODING_4_8,sf=12