RF Question, What has better range capability, GFSK or FSK?

[MatCat]

I am working on a project that uses RFM22B UHF modules for use as control radio for model aircraft, and I am curious to know what would have a better range capability in theory, GFSK or FSK?  I am sure this would be an easy question for any RF engineer.  I looked around on the internet and I couldn't really find a good answer to satisfy me.

[hlavac]

These are just two very similar modulation schemes, they will be about the same.

[calmtron]

As hlavac says, they would have the same range. GFSK will use a smaller part of the spectrum (and therefore waste less power).
Disclaimer: Not an RF engineer.

[w2aew]

It really comes down to the receiver design.  Since GFSK occupies less BW for a given symbol rate, the receiver can be made more sensitive by using a narrower filter (thus, less total integrated noise).  The receiver will also have to be optimized for the gaussian filtered data, which may have a little intersymbol interference.  But, by doing these things - GFSK should have a slight edge.

[KJDS]

Unless the receiver design is poor, or suffering interference, then if you can see the plane then it should receive ok with either GFSK or FSK.

[Paul Price]

GFSK makes the FCC spectrum happy but tends to compromise the distinction between 1's and 0's. FSK will work best at the longest distance because the frequencies are sharply defined and thus less prone to have noise damaged packets received.. If your project is just for you go with FSK, it is easier to troubleshoot and work with and will give you a better range.

[MatCat]

GFSK makes the FCC spectrum happy but tends to compromise the distinction between 1's and 0's. FSK will work best at the longest distance because the frequencies are sharply defined and thus less prone to have noise damaged packets received.. If your project is just for you go with FSK, it is easier to troubleshoot and work with and will give you a better range.

Looking at the transmission using an SDR I would concur, it was my thought that FSK would have better range potential because it's signal seemed indeed significantly stronger then GFSK, at 19.2k baud FSK only had a few KHz of bandwidth extra anyway!