# Actual Received power from RSSI

**URL:** <https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514>\
**Category:** Uncategorized\
**Created:** [August 29, 2020, 6:23am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514 "2020-08-29T06:23:02Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![Saeedmagsi](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/saeedmagsi/32/25844_2.png) [@Saeedmagsi](https://www.thethingsnetwork.org/forum/u/Saeedmagsi)\
**Post date:** [August 29, 2020, 6:23am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/1 "2020-08-29T06:23:02Z")

</div>

Hello everyone. I need to find out the actual received power from RSSI. I have read somewhere that Pr=(RSSIi+RSSIoffset). Now how can I find this offset. It was written that RSSIoffset can be find out empirically. But I could not understand that statement. Please help.

---

<div class="post-metadata">

**Author:** ![LoRaTracker](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/loratracker/32/48502_2.png) [@LoRaTracker](https://www.thethingsnetwork.org/forum/u/LoRaTracker)\
**Post date:** [August 29, 2020, 7:59am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/2 "2020-08-29T07:59:52Z")

</div>

> [@Saeedmagsi](#):
>
> It was written that RSSIoffset can be find out empirically. But I could not understand that statement. Please help.

A dictionary definition of ‘empirically’ is;

“in a way that is based on what is experienced or seen rather than on theory”

So maybe you need to actually measure it.

Might be helpful if you told us why you ‘need’ to know the difference between what **some unkown radio device** is telling you and what its actually receiving in terms of signal strength.

---

<div class="post-metadata">

**Author:** ![Saeedmagsi](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/saeedmagsi/32/25844_2.png) [@Saeedmagsi](https://www.thethingsnetwork.org/forum/u/Saeedmagsi)\
**Post date:** [August 29, 2020, 8:55am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/3 "2020-08-29T08:55:17Z")

</div>

I want to find out the path loss exponent. Based on these values I want to apply localization. Therefore I need received power (not rssi).

---

<div class="post-metadata">

**Author:** ![LoRaTracker](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/loratracker/32/48502_2.png) [@LoRaTracker](https://www.thethingsnetwork.org/forum/u/LoRaTracker)\
**Post date:** [August 29, 2020, 9:28am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/4 "2020-08-29T09:28:28Z")

</div>

Then you need the, presumably calibrated equipment to measure it.

And you have still not said what radio device you are using ?

---

<div class="post-metadata">

**Author:** ![Saeedmagsi](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/saeedmagsi/32/25844_2.png) [@Saeedmagsi](https://www.thethingsnetwork.org/forum/u/Saeedmagsi)\
**Post date:** [August 29, 2020, 9:51am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/5 "2020-08-29T09:51:38Z")

</div>

Well I am using dragino lora shield as my ED and Risinghf gateway.

---

<div class="post-metadata">

**Author:** ![kersing](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/kersing/32/44777_2.png) [@kersing](https://www.thethingsnetwork.org/forum/u/kersing)\
**Post date:** [August 29, 2020, 10:29am UTC](https://www.thethingsnetwork.org/forum/t/actual-received-power-from-rssi/39514/6 "2020-08-29T10:29:53Z")

</div>

> [@Saeedmagsi](#):
>
> I want to find out the path loss exponent. Based on these values I want to apply localization.

That will only work if you know exactly how much transmission power is being used and what the cable/connector/antenna losses/gains are for both the sending and receiving parts.  
The easiest way to get numbers is to use your devices, transmit multiple times at 100m, 200m, 300m and so on and use the data to calculate the offset. However, keep in mind a different device with different antenna wil get you different readings so calculating distances this way will not work. Not to mention complicating factors like ADR (which might have a node transmit at lower power) and multipath or reflected signals.

Next