How to Measure Communication Performance? [Video 3]

[@esamalmohimmah3242]

Nice and simple explanation. I hope you continue making videos like this and cover different communications topics as much as possible.

[@abdulazizalakoub1087]

Thank you very much Prof. Emil, It's very helpful information.

[@rezaroshanghias4463]

Dear professor Bjornson, for what reason, in the definition of the channel capacity, the length of the block is assumed infinity?

[@WirelessFuture]

The reason is that the decoding error probability goes to zero as the block length goes to infinity. A more in-depth description is provided in the following video: kzbin.info/www/bejne/jIa9hJlog9GHr68

[@rezaroshanghias4463]

Dear Professor How can we calculate the packet error probability? Is it true to say that because packet error probability depends on channel coding kind and modulation scheme type we do not consider it as a performance metric in 5G?

[@WirelessFuture]

The packet error probability depends on the modulation and coding, thus it is often hard to compute it analytically. But one can compute it experimentally and determine how large the SNR should be to get the preferred packet error probability. This is how one uses it in 5G and other standards. Pick the modulation-coding scheme that gives the highest rate while satisfy your PEP target value. Since large packets are usually transmitted, the channel capacity gives a good indication of what the rate of the best modulation/coding scheme will be.

[@박희재-k2p]

Dear professor, when we say the word "code", is it the same word with "encoding"?

[@WirelessFuture]

Yes

[@deerajkumarj1408]

Sir, mostly capacity is represented in bits per channel use. What is the reason for this

[@WirelessFuture]

This is the most general unit. The number of channel uses (=modulation symbols) per second depends on the bandwidth and pulse-shaping. Hence, we don’t need to make assumptions about those things when considering the unit bit/channel use.

[@deerajkumarj1408]

@@WirelessFuture Thank you very much for explaining this sir.

[@marcinrybakowski8926]

Dear Professor, Why we have sqrt(channel gain) in formula but not just channel gain?

[@WirelessFuture]

The channel gain, as we define it, is the power loss. The formula is considering the signals themselves, not their powers. Hence, we use the square root of the power loss to get the amplitude loss.

[@marcinrybakowski8926]

@@WirelessFuture thank You

[@mosesinuwa5044]

Thanks for the video. Help me a video on how to calculate 5G capacity and coverage