Why does the Total TX Power (conducted) decrease as MCS rate increases?

[gcarmich]

I reviewed the RF Performance table for the MR86 and noticed that the Total TX Power (conducted) decreases as the MCS rate increase:

https://documentation.meraki.com/MR/MR_Overview_and_Specifications/MR86_Datasheet

1. Why does the Total TX Power (conducted) decrease occur?  

2. What is Total TX Power (conducted) measured in?

Thank you,
Gil

[alemabrahao]

Rememver 1mW = 0dBm which is the reference value. dBm value is equal to 10log(power in mW/reference value).

This will result

0.1mW= -10dBm

1mW = 0 dBm (Reference value)

10mW = 10dBm

100mW = 20dBm

1000mW = 30dBm

To estimate other values we use rule of 10 (10 times in mW = + 10dB or 1/10th of power = -10dB) and rule of 3 (double the power in mW = +3dB or half the power = -3dB).

if you go by that then 40mW = 10mW x 2 x 2 which is same as 10dBm+ 3dB + 3dB = 16dBm

So 100mW-> 40 mW is same as 20dBm -> 16dBm which is -4dBm

[alemabrahao]

This is the basics of Radio Frequency, so I suggest you read this article and I also suggest you study a little about the basics of wireless.

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/23231-powervalues-232...

[gcarmich]

Thank you!  I'll check out the article.

Is the Total TX Power (conducted) measured in mW?