Calculating Gain for a datasheet?

[ry1808]

Hi, 1st post here so please be kind!

I have developed a velocity sensor which gives an output in mV/mm/second. I now need to generate a datasheet for this device but for the life of me I can't remember the formula for calculating gain.

If my sensor is calibrated to have a response of 4mV/mm/sec at 100Hz then I thought my gain values be calculated as follows:

log10 (value x/4)

I have tried this and the results say that in my frequency range 2Hz - 10kHz the gain never varies by more than 1dB. I would have expected it to be far more.

Am I missing something obvious here?

Thanks,

Richard

 

[Laplace]

If the sensor is already calibrated to provide a certain voltage for a specified velocity, 4mv/mm/sec, then what more needs to be done? Whereas gain in dB would be defined as the power ratio of an output voltage to an input voltage or reference voltage. What signals would you be using to establish the power ratio? How is frequency related to velocity? Why is frequency important if the sensor is already calibrated for velocity?