Decibel Sum

Function dBsum(dBcells, Coherent)
' Sum dB values as 10*log(10^(dB1/10)+10^(dB2/10)+...) for Coherent=FALSE
Dim dB As Range

If Coherent = False Then
    tot = 0
    For Each dB In dBcells
        tot = tot + 10 ^ (dB / 10)
    Next dB
    dBsum = 10 * Log(tot) / Log(10)

Else
    tot = 0
    For Each dB In dBcells
        tot = tot + 10 ^ (dB / 20)
    Next dB
    dBsum = 20 * Log(tot) / Log(10)

End If

End Function