In some paper,the unit of attenuation is dB/(MHz/cm).what's the difference between dB/(MHz^y cm) and dB/(MHz/cm) and what does y mean?
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what's the difference between dB/(MHz^y cm) and dB/(MHz/cm) ?
(5 posts) (2 voices)-
Posted 4 years ago #
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Hi wang_feng_2020,
The absorption in many materials follows a frequency power law of the form a0 * f ^ y. Here a0 is in units of dB/(MHz^y cm), and f is frequency in units of MHz.
If y = 1, there is a linear dependence on frequency, and the units would then be dB/(MHz cm).
Brad.
Posted 4 years ago # -
thank you,Bradley.
in a database,the unit of absorption is dB/（MHz/cm） and b is 1.5.(i don't know whwther b is y ) But if b is y, how do I convert units to dB/(MHz^y cm)?Posted 4 years ago # -
Hi wang_feng_2020,
That doesn't sound dimensionally correct. Maybe they listed the units wrongly?
Brad.
Posted 4 years ago # -
Thank you,Brad.
Maybe they think dB/（MHz/cm） is same as dB/(MHz^y cm).Iin one paper,I find this:"The attenuation coefficient (α) varies with frequency as:α=a * f ^ b.where coefficient a has units of Np/cm/MHz, f is the frequency in MHz, and coefficient b is dimensionless. "Posted 4 years ago #
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