The Reception sensitivity of a wifi repeater is: " 270m: -68dBm at 10% per" , what the meaning of these numbers?

Question

I want to get a WiFi repeater so I looked for its specification on the internet .. I want it to have a wide range.

Here is the specification of Reception sensitivity:

270m: -68dBm at 10% per
130m: -68dBm at 10% per
108m: -68dBm at 10% per
54m: -68dBm at 10% per
11m: -85dBm at 8% per
6m: -88dBm at 10% per
1m: -90dBm at 8% per

What do these numbers mean? Can I get internet with it from a 270 m far AP?

Here is the repeater I am talking about : http://www.lb-link.cn/index.php/products/view?pid=117

Answer 1

Each line specifies a data rate, achievable signal sensitivity level and error rate.

Data rate is in megabits per second.
eg 270 m = 270 b/s

Sensitivity is in dBm = dB referenced to 1 milliWatt.

As Cristobal Rojo & Rustyx advise : PER = Packet Error Rate.

So

 270m: -68dBm at 10% PER

means 270 Mb/s at a sensitivity of -68 dBm with 10% packet error rate.

....

1m: -90dBm at 8% PER

means 1 Mb/s at a sensitivity of -90 dBm with 8% packet error rate.

____________________

To convert dBm to milliWatt use
mW = 10^(dBm/10)
So eg -90 dBm - the most sensitive available - but at only 1 Mb/s
mW = 10^(-90/10) = 10^-9 mW = 1 nano-Watt
Wow!

In your case to get 270 Mb/s you need at least -68 dBm at the receiver.

Assume 20 dBm transmit power (100 mW)
Total loss 'budget' = 20-68 = 88 dB

You can use the formulae from eg Wikipedia

seen here:

Still from Wikipedia:

"For typical radio applications, it is common to find f measured in units of GHz and d in km, in which case the FSPL equation becomes

FSPL(dB)20log{10}(d) + 20log{10}(f) + 92.45

For d,f in meters and kilohertz, respectively, the constant becomes -87.55 .
For d,f in meters and megahertz, respectively, the constant becomes -27.55 .
For d,f in kilometers and megahertz, respectively, the constant becomes 32.45"

__________

Or plug figures into one of the many online calculators.
eg at Pasternack

Which tells you that eg 1 km at 2.4 Ghz with zero aerial gain = 100 dB path loss.

At 10 dB aerial gain at both ends gives 80 dB path loss = about OK in your case.
So about 1 km with 10 dB gain aerials at both end.

I could launch into dBi and more, but instead YOU should read up on the subject if you want to understand it somewhat.

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Answer 2

PER = Packet Error Rate, Packet Error Rate (PER) is used to test the performance of an access terminal's receiver

http://rfmw.em.keysight.com/rfcomms/refdocs/1xevdo/1xevdo_meas_cperror_desc.html