<br>I don't have a lot of background on wireless communication<br>
but as far as I understand,<br>
applying IFFT on Channel Frequency Response (CFR)<br>
would transform the data into time domain Channel Impulse Response (CIR),<br>
in which it shows the delay spread of the different multiple paths.<br>

The CSI measuring tool I'm using measures 30 subcarriers <br>
resulting in 30 complex number CFRs per a single CSI trace.<br>
So when I apply 30-point IFFT on the CFR, <br>
the output is a CIR with 30 time-domain values.<br>

My question is, what is the time unit of the converted CIR?<br>
How much seconds are they (the 30 impulse responses) apart?<br>

Also, are the impulses (excluding the direct path)<br>
like the echoes of the transmitted signal?