Specifying the channel name of function output

I want to be able to change the channel name of the output of a function, such as ChnFFT1()

From my script:

FFTIndexChn      = 0
FFTIntervUser    = "NumberStartOverl"
FFTIntervPara(1) = 1
FFTIntervPara(2) = 96000
FFTIntervPara(3) = 1
FFTIntervOverl   = 0
FFTNoV           = 0
FFTWndFct        = "Rectangle"
FFTWndPara       = 10
FFTWndChn        = "[1]/Time"
FFTWndCorrectTyp = "No"
FFTAverageType   = "No"
FFTAmplFirst     = "Amplitude"
FFTAmpl          = 1
FFTAmplType      = "Ampl.Peak"
FFTCalc          = 0
FFTAmplExt       = "No"
FFTPhase         = 0
FFTCepstrum      = 0
Call ChnFFT1("[1]/Time","[1]/AI2")

What do I have to add to be able to control the output channel name?

Thanks!