ESP8266 Community Forum

Hello i wonder if it is possible to detect a strength if it is in front of me or in back of me and how far if in range? Is this possible or impossible? I know there is a way for wifi routers and hot spots to do it.


Joseph

Signal strength decreases with distance. Unfortunately it gets messier after that.

Signal strength decreases more when it goes through other materials/bodies. Reflected signals can add to, or subtract from, the direct signal. Antennas are not consistent in their radiation pattern. Rotation will affect the signal. Antenna height makes a difference. Surrounding materials make a difference.

I know there is a way for wifi routers and hot spots to do it.

Yes but how often are they correct?

Signal strength can be used but if you need it to be accurate then it may not give you what you want.

Thank you for this information. I know it is hard and it is something i have been looking into. But what i would like to do is not possible with a esp8266.


But I'm not giving up. I'm looking into other ways of doing the same things. Staytune...

josephchrzempiec wrote:Hello i wonder if it is possible to detect a strength if it is in front of me or in back of me and how far if in range? Is this possible or impossible? I know there is a way for wifi routers and hot spots to do it.
Joseph

Hi Joseph ~ what you are asking is actually three different things ... wifi signal strength, distance, and direction. Strength doesn't always equal distance ... therefore some routers will use Time of Flight (ToF) methods to determine how far a client device is ... but this is only partially affected by the rssi ... and out of the scope of the esp266's sdk ... so determining distance ... not so much for the esp ... there is a whole forum and project right here https://www.esp8266.com/viewforum.php?f=161 talking about this ... Now that leaves us direction ... most all of the esp8266 boards have omni-direction antennas that are sensitive in all directions ... some esp8266 boards have external antenna connectors ... and if you use a yagi directional (only in one direction) antenna ... you would be more likely to determine the direction of the signal by watching the rise and fall of rssi as you swept the antenna's orientation ... good luck and keep us updated