how to detect multiple peaks?

[cantata2014]

For example, this is a spectrum. Y-axis is power, and X-axis is frequency. 

I have the measured datas (two 1-D arrays), and I want to detect the multiple peaks. Can anyone tell me how to do it? Thanks!

[cantata2014]

For a single peak like this, I can use the ArrayMax&Min function to find the peak value..

But for multiple peaks,  my idea is that set a threshold (eg:power=-10dB), and cut these spectrums into several peaks like this:

and then, find the Max value for each set. But I don't know how to realize this....

[altenbach]

Peak detector