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Your question is pretty unclear, but here goes: What you are calling a binary input is the Modulating signal. The Carrier is the signal that is modulated. When you say binary input frequency, I think the concept to which you are trying to refer is Bandwidth. In a real system at RF frequencies, the carrier frequency has to be higher than the bandwidth of ...

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ISI is an (typically undersired) effect of the channel – that can be a cable, an optical fiber, free space or the air you use to transport your wave. The different kinds of constellations are a method of putting data in a waveform. So, they are connected: The modulations define which symbols your system uses. ISI is what happens to the symbols when you ...

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That’s is because of the delay in the GMSK demodulator. MATLab GMSK demodulator uses Virtebi algorithm. You should delay the Rx BER in order to get back the correct data alignment.

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Frequency by definition is the derivative of phase with respect to time (a change in phase divided by the change in time is frequency). You see this with the radian expression for frequency given by $2\pi f$: A frequency of 1 Hz is 1 cycle per second which is $2\pi$ radians per second. So similarly phase versus time is the integral of frequency versus time. ...

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You need to integrate the modulating signal because frequency is the time derivative of phase. Therefore, the typical relationship from introductory calculus holds: $$\phi_i(t) = \int_{-\infty}^{t} \frac{d\phi_i(\tau)}{d\tau} d\tau = \int_{-\infty}^{t} 2\pi f_i(\tau) d\tau$$ For causal signals, the lower limit on the integral changes to zero:  \phi_i(...

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