Setting tx/rx power on the antenna (external especially)

General
1

Hello Folks,

Two questions related to photon:

1-) I read that it is possible to select external and internal antenna through software. But is it possible to adjust the level of power (tx/rx power) to the external and/or internal antenna through software (python etc…) and/or firmware? Can you provide me examples source codes?

2-) I guess photons can measure and show RSSI value through software, isn’t it?

Thanks in advance…

Kemal

2

No guessing needed, the docs do tell :wink:

The transmission power is modulated as needed by the system, so there's probably little to gain my fiddling with it yourself.

BTW, no native pythoning with these devices, the firmware uses C/C++.

1 Like
3

The WiFi spec says what has to happen with TX power under certain circumstances--you can't just change it as a user and have a device that passes RF testing limits etc. so there is no exposed API to change it.

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4

Thanks guys,
My goal was to compare the power consumption of two different external antennas.
One is omni-directional and the other is directional.
So I guess photon will give them equal tx power, which means you can not compare their power consumption.
Probably the directed antenna will have longer range with the same level of power.
I just wanted to keep the range same in both antenna types by lowering the power level
when I hook up directional antenna, assuming that it can transmit to bigger range.

Well any suggestions?

5

You should be able to lower power levels by using directional antennas on both units which should give a better signal reception at lower power levels.

Using a directional wifi antenna with my Phantom DJI drone made a huge difference in range.

6

Hi,

Try looking at a YouTuber called Andreas Spiess.

Optimizing Antennas

Hes looked in to issue of getting the most of of Antennas and has done 3 or four videos examining this. If nothing else it is interesting.

Liam

7

You should get a hold of the datasheets for the two antennas. They will show the radiation pattern and overall gain/loss of the antenna relative a standard model for antenna design called an isotropic antenna (hence the dBi measurement).

There is no free lunch with antenna design. If a particular antenna has a longer distance rating, it achieves this by reducing the signal in other areas making it more directional and more powerful along that one direction.