Re: [Discuss-gnuradio] bell 202 modulation

[Rick Parrish]

John Ackermann N8UR wrote:

> the use of AFSK with 1200 and 2200Hz tones is simply an artifact of that.

Instead of toggling back-and-forth between two independent tone sources, 
how hard would it be to create samples for a 1200 hz tone spanning one 
symbol period where the initial phase was arbitrary eg. if you used a 
sin(theta) function, it wouldn't always start at theta = 0. Same for the 
function to generate samples spanning one symbol period for the 2200 hz 
tone.

The idea I'm getting at is you could have your signal transition 
smoothly (as possible) between the two tones which would result in a 
cleaner, more efficient signal.

A sample rate that is an integer multiple of the symbol rate is a nice 
thing but isn't required.

-rick