Recently, I have been coming across the news on BLE/ BT 4.0 on "Home Automation". However, I would like someone to clear my queries (my knowledge in electronics/ networking is limited)

 

1. Cost of BLE vs Zigbee vs Z-wave technology?

2. Can devices with older Bluetooth versions (BT 2.0 or BT 2.1 or BT 3.0) communicate with a device (say iPhone 4S) installed with BT 4.0 technology?

3. I read, that the range of Class-I BT compatible device is 100m and the range of Class-II BT compatible device is 10 m. So, if both the devices are placed 90 m apart, can both the devices communicate now via BT (since the Class-I device doesn't fall within the range of Class-II BT signals)?

4. Signal range of Zigbee and Z-wave?

5. What are the advantages/ disadvantages and the hazards of higher frequency ranges (The frequency range of BT and Zigbee is 2.4 GHz and Z-wave is ~908 MHz)?

 

and finally

 

6. Which of the three is more hazardous in terms of signal radiation emission?

 

Regards

To what hazards do you refer?

Apologies! Hazardous is a wrong word. Which of the three emits higher microwave radiation?

Could someone please answer me at least any one question posted above?

 

Regards