Difference between NRF24L01 & LORA SX1278

LoRa devices are packet based tranceivers, max 256 bytes, operating at the physical layer. The devices themselves do not have a protocol as such.

Send and aknowledge can and is available via various software implementations and libraries.

THANK YOU FOR YOUR PROMPT REPLAY.... :slight_smile:

ACTUALLY, I AM TRYING TO CONTROL MY DSLR CAMERA FROM ITS GIMBAL HEAD USING DC MOTORS AND JOYSTICK CONTROLLERS (FOR WILDLIFE PHOTOGRAPHY ). I ALREADY DONE THIS JOB BY SOME CHEEP RADIO CONTROLLERS (433MHZ) JOINED WITH ARDUINO UNO AND MEGA. STILL, RANGE IS A ISSUE THAT IS WHY I CAME UP TO LORA SX1278.

MY QUESTION IS IF WE HAVE TWO SX1278, CAN WE USE THEM AS A RF TRANSCEIVER TO SEND DATA BETWEEN TO ARDUINO FOR REMOTE CONTROL

VIDEO IS STREAMING TO MY PC TROUGH A INTERNET DEVICE ATTACHED TO THE CAMERA AND I CAN EVEN TAKE PICTURES AND BRING BASIC ADJUSTMENTS TO CAMERA FROM MY PC, BUT STILL ZOOMING, MOVING CAM IN X-Y-Z AXIS IS GIVING SOME TROUBLE... I AM NOT GOOD WITH ARDUINO AND PROGRAMMING AND REALLY NEED SOME HELP...

Why are you SHOUTING AT US?

...R

I am not shouting but crying............

I am new to Arduino and these wireless modules, So really need some help!

darison01:
I am not shouting but crying...........

Text written entirely in upper case is actually very hard to read.

And, sorry, I am not familiar with LORA

...R

Long distance (4km) ground range control is quite difficult, but it does rarther depend on the exact terrain.

If you have already tried the 433Mhz long range radio control systems (such as openLRS) and they are not good enough then LoRa is the clear choice, it ought to go around 10 times further.

There are code Libraries for LoRa but I am not aware of an off the shelf example that will do what you want.

Robin2:
Text written entirely in upper case is actually very hard to read.

And, sorry, I am not familiar with LORA

...R

it's okay, let me start with and I will update with the project progress....

And actually, if it works within 1000m itself will be a huge goal!

Once again thank you all for support....

darison01:
And actually, if it works within 1000m itself will be a huge goal!

Your first post said you wanted 4km, so if this is now reduced to 1km, what is the real minimum distance you actually want ?

What do you get at the moment, 200m ?

Lora simply translates range for bit rate, ie longer range = slower data rates.
Theres nothing magic about this other than its a bit harder to do that with the more simplistic radios that most people use, because you need a form of spread spectrum radio to do this.
Range is also a bit problematic as its also highly dependant on whats in the way.
Trees for example are very good absorbers of RF above around 400 Mhz.

mauried:
Lora simply translates range for bit rate, ie longer range = slower data rates.

Most standard FSK RF modules require a signal that is between +5dB and +10dB above noise level for them to be received.

LoRa is spread spectrum and will receive signals at between -7.5dB and -20dB below noise level.

Thus in most situations LoRa has a link advantage of around 20dB when used at the equivalent data rate as a FSK module.

mauried:
Trees for example are very good absorbers of RF above around 400 Mhz.

I have measured the effect.

With a LoRa transmitter at ground level in the undergrowth (worse case really for the TX) and a handheld receiver 1500bps LoRa will cover around 1000m in a wet forest and 2000m in a dry one.

And if you were to drop the data rate to 100bps, enough for a lot of sensor type applications, range will increase by a factor of 3.

srnet:
I have measured the effect.

I'm curious about LoRa so may I ask a question?

In the case where you are at the limiting range for the conditions (1000m in the wet forest, for example) and you send a single message (say) "Hello World" is it guaranteed to get to the Rx and how is that guarantee achieved? (For example are there automatic acknowledgements and retries?).

...R

Robin2:
I'm curious about LoRa so may I ask a question?

In the case where you are at the limiting range for the conditions (1000m in the wet forest, for example) and you send a single message (say) "Hello World" is it guaranteed to get to the Rx and how is that guarantee achieved? (For example are there automatic acknowledgements and retries?).

...R

The base LoRa devices are just packet transmitters and receivers, there is no built in acknowledge and retry, which is the situation for a lot of RF modules.

If you want automatic acknowledgements and retries you need to build it into the driving software.

My own balloon tracking software has a queued_send() function. When the remote tracker (could be 200km + away) wakes up from sleep, it transmits a clear to send packet. This is picked up be the receiver which then sends the queued data. The receiver will keep doing this until the remote tracker responds with an acknowledgement.

srnet:
This is picked up be the receiver which then sends the queued data. The receiver will keep doing this until the remote tracker responds with an acknowledgement.

Am I correct to interpret this to mean that it is entirely a matter for the user's code to ensure that a message is received and acknowledged?

If so, that suggests to me that there could be an unpredictable interval between first trying to send a message and being able to conclude that communication was successful or that communication had definitely failed.

And if that conclusion is correct it seems to have implications for the suitability of LoRa in the OP's motor control project. However I am not suggesting there is a more suitable affordable alternative.

...R

Robin2:
Am I correct to interpret this to mean that it is entirely a matter for the user's code to ensure that a message is received and acknowledged?

If so, that suggests to me that there could be an unpredictable interval between first trying to send a message and being able to conclude that communication was successful or that communication had definitely failed.

And if that conclusion is correct it seems to have implications for the suitability of LoRa in the OP's motor control project. However I am not suggesting there is a more suitable affordable alternative.

...R

Your correct in that its up to the users code to ensure a message is received and acknowledged.

However your conclusion is not correct, LoRa has been in use for a while for very long distance remote control of RC models in flight, for one example see here;

TBS Crossfire 100km

TBS Crossfire - What is it ?

If LoRa is good enough for very low latency control of a model in flight, it ought to cope with a far less demanding application of remote control of a camera.

srnet:
Your first post said you wanted 4km, so if this is now reduced to 1km, what is the real minimum distance you actually want?

Actually, to get control over my camera from home it will take around 3 to 4 Km, but if I manage to get a shelter nearby to the field a network coverage of 800-1000M will be enough!

darison01:

srnet:
Your first post said you wanted 4km, so if this is now reduced to 1km, what is the real minimum distance you actually want?

sorry for the error...

Actually, to get control over my camera from home it will take around 3 to 4 Km, but if I manage to get a shelter nearby to the field a network coverage of 800-1000M will be enough!

srnet:
However your conclusion is not correct, LoRa has been in use for a while for very long distance remote control of RC models in flight, for one example see here;

Thanks for that.

Do you know how they achieve low latency?

And I presume the RC model control system has a certain amount of autonomy - like a drone does - so that it can survive without instructions for a reasonable period. If you can't see the model you won't be trying to fly it between the branches of trees.

...R

Robin2:
Thanks for that.

Do you know how they achieve low latency?

And I presume the RC model control system has a certain amount of autonomy - like a drone does - so that it can survive without instructions for a reasonable period. If you can't see the model you won't be trying to fly it between the branches of trees.

No idea how they acheive the low latency and I have no particular interest in long range RC model control, since its not legal to fly models beyond visual line of sight and standard 2.4ghz systems are fine for that.

You often dont need two way comms as long as the packet rate is high enough. The worse that will happen is that the receiver misses a packet and the servo\motors stay where they are until the next packet arrives.

I have thought of doing a long range remote control setup myself to allow you to control relays, lights and servos over a long range LoRa link, and feedback would be useful in that case.

srnet:
No idea how they acheive the low latency

I am inclined to think that they don't :slight_smile:

...R