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Is it possible to do FSK modulation with IQ modulators?

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7rots51

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Is it possible to do FSK modulation with IQ modulators?
 

7rots51

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Do you have PDF,link app note links?I need some data and info
 

flatulent

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You can do MSK with rectangular pulses to I and Q.

For two state FSK you put the proper triangular waves into I and Q to make the vector rotate clockwise or counterclockwise. (advancing phase or retarding phase)
 

7rots51

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how to convert my stream of data to that "proper triangular waves " ?,it it possible to give more details or articles?thanks
 

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I deduced the triangle method from a thought experiment. I have no practical experience doing it in hardware.

[added next day] After more thought, you use sine and cos instead of the triangles. I is cos wt and Q is sin wt. Where w is the frequency shift. For shifting the other direction use -wt which changes the sign of sin but not cos.

You can generate these with two integrators in a loop with some sort of amplitude limiting control.
 

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