Find Bandwidth Efficiency (R/B) given SNR and Eb/N0

[lycaeus]

Thank you in advance for your help!What is the bandwidth efficiency (R/B) of PSK for a bit error rate of 10^-7 on a channel with
an S/N of 12 dB?[/b]
From the graph, for BER= 10^-7, Eb/N0 = 11.2 dB./b]I have applied the formulae Eb/N0 = S/N * B/R
Where, S/N is Signal power over noise power * Bandwidth / Bit Rate

I know for one that I need to convert dB to dBW by applying 10log(dB)

However, I have tried for 5 hours and could not get the answer

The answer to this question is 1.2

Thank you

 

[marcusl]

It looks right to me. Are you making an arithmetical error? Why do you think dBW enters?
You have
R/B (dB) = SNR(dB) - (Eb/No)(dB)
in dB, it is simple to convert to a power ratio.