433mhz vs 2.4ghz vs Bluetooth

Hi!
I have a simple arduino nano sending some values (temperature, humidity, light sensor, pir sensor, ...) to another arduino uno.
Right now I have an 433mhz transmiter doing the work.

But now I want to add more arduino nanos to send more values from diferent locations. Will i be able to have multiple 433 transmiters sending to the same receiver?
Should i change to 2.4ghz or bluetooth?

And also, in Europe is there any restriction to the use of this frequencies?

thanks!

You can use 433 if you want, but you either assign them id's, or send data at specific interval do your comm's don't collide.
bluetooth is great, but is range limited.
2.4 ghz, uses more pins ( from the ones that I have looked at. 6 pins, if I recall.
As for frequency restrictions,...........no clue!

In Europe, the 433MHz, 868MHz and 2.4MHz can be used with limited power.
Although I'm not sure if that is the same for every country.

For the 433MHz, a transmitter may only transmit during 10% of the time.

Do you use those cheap ASK modules with the VirtualWire library ? You can use many transmitters, but you have to add an identifier. So the receiver knows which one was transmitting (and what kind of data it is).

You might even add encryption. When you add a random value or a counter to the data, and use encryption, the data is totally different every time, even if the same temperature was measured.

Bluetooth is only short range.
There are good transceiver modules for 433MHz and 2.4GHz. Google for "Sparkfun wireless buying guide" to see a nice list of possibilities. Or check the modules that are supported by the RadioHead library at airspayce.com/mikem.

(while I was typing this, blcodemonkey already wrote about ID's and limited Bluetooth range)

2.4 and Bluetooth are on the same freq. BT has short range unless if you get into the higher spec'd BT, like v3.0+. Normal 2.4 is limited to 100mw in the EU depending if you have the correct channel hopping specification. 433MHz is limited to 10mw (if I remember correctly) but potentially can perform better due to the better wavelength behaviors. Of course, you can always run higher power/higher duty cycles if you want to be illegal.

Depending on you skill level is what you might want to dive into. Some systems are harder to work with than others. Find a good, user friendly kit would be the most important thing to me. But I lack skills...

thanks for the help!

right now, i have an 433MHZ transmiting every 10 minutes, so I think I'm very far from the 10% on time each hour!

Regarding the bluetooth i'm really thnking in moving over to bluetooh, the max range i need is just near 5meters in open space... so I think it will be enought.
And with bluetooth i will be able to connect a lot of arduinos and to use them as transceivers.
If i need more range I can also use them as a network or range extenders and send info from device to device until it reaches the last one..

I also like bluetooth cause them I'll be able to connect it to my android phone!

Does anyone sees any problem besides the range into moving on to bluetooth?

The BLE is designed for small microcontrollers.

Range is the major trouble and costs and initialization.
If you already know that you are going to use a mesh network or node hopping (I don't know what it is called), then Bluetooth might not be right choice.

When you have some remote sensor for temperature, you can keep that at 433MHz. Perhaps one module could be the 433MHz receiver and is connected to the Bluetooth network.

I am thinking in investing good money in this area of 434MHz IoT using SOC devices that include the UART and codespace as EEPROM so that the MESH or node hopping style can co-exist responsibly. PLEASE DO NOT just think you can ignore the hard work of many people who have considered carefully how this technology can be effective as a shared resource with little or no restriction other than working to allow more than one person to use it in their neighbourhood! I wonder just how much people need to know before buying one of these pieces of technology? I am not a corporate, I am spending my benefit money on something I wish to share with many other people who need to know their elderly parents are safe while they go to work or go shopping. This is the potential reality for the new technology of IoT or Internet of Things. The other frequency is 868MHz. Take a look at the "Network of Things" kickstarter project if you would like to see what people are trying to do for other people across Europe! Good Hunting!

arclite_7:
PLEASE DO NOT just think you can ignore the hard work of many people who have considered carefully how this technology can be effective as a shared resource with little or no restriction other than working to allow more than one person to use it in their neighbourhood!

Why exactly can't he ignore it? Just being a devil's advocate here.

fabmsg:
Does anyone sees any problem besides the range into moving on to bluetooth?

Yes, this

I want to add more arduino nanos to send more values from diferent locations.

NRF24 or the like is a better bet for a network. You may then have one arduino talk to phone via bluetooth.