Why does bluetooth have a signal range and data transfer rate less than that of wifi?

Question

Bluetooth

Bluetooth and Wi-Fi operate at the same frequency, then why do they have different range and signal speed ?
-As far as I remember, the range of the signal depends on the frequency?

Answer 1

This is affected by the peculiarity of the use of channels.
WiFi 802.11b/g/n has a total of 13 channels (bandwidth), with most using a 20MHz bandwidth. The channel is selected by the access point and does not change during operation. If someone else occupies this channel, failures begin, the speed drops, the range too. Therefore, WiFi is convenient when there is one access point and many client devices.
Bluetooth has 79 channels, each 1 MHz wide, and all are used at the same time. Devices switch between channels according to the agreed scheme. And if two devices accidentally collide on a channel and interfere with each other, only a small portion of data is lost, which will be retransmitted after switching to another channel (1600 or 3200 times per second!). Accordingly, Bluetooth is convenient when there are many devices and they all communicate with each other.
In short:
- Bluetooth speed is less due to the smaller channel width (1 MHz versus 20 MHz for WiFi)
- Bluetooth range is shorter due to high requirements for air purity (operating range of 79 MHz versus 20 MHz for WiFi)
- Bluetooth survives better a situation where there are many "masters"
PS I'm not an expert, I could be wrong :) I'm not especially sure about the range. for example, BT headphones take 100 meters normally, and through walls ...

Answer 2

The range of the signal depends primarily on its power.
their signal speed is the same, about 300,000 km/s.
and all the differences are because of what different people did, according to different standards and for different purposes.