# Tag Info

### How to "draw" the function/wave to send symbols using QAM?

The baseband QAM signal is complex, and the only way to draw it is by doing two drawings, one for the in-phase (real) component, and one for the quadrature (imaginary) component. The passband QAM ...
• 13.8k
Accepted

### Real and complex low pass equivalent of band-pass signal

It's not true that any real-valued band pass signal can be written as shown in your first equation: $$s(t)=A(t)\cos(\omega_c t)\tag{1}$$ The most general representation of a real-valued band pass ...
• 80.2k

### Calculate and interpret the instantaneous frequency

At least f2 and f3 seem to work appropriate on a pure chirp signal, but all methods, including f2 and f3 seem to fail horrible, when it comes to more than one frequency in the signal. In reality ...

### Calculate and interpret the instantaneous frequency

Not really an answer but maybe helpful: Personally I found that the concept of instantaneous frequency is only useful for sufficiently narrow band signals. Consider the simple example of two steady ...
• 31.5k
Accepted

• 6,068
1 vote

### Compute real signal from a discrete analytic signal

@user85858302: If designing a complex-valued bandpass filter is the solution to your problem, you can design such a filter without using the Hilbert transform. Start by using your favorite method for ...
• 4,838
1 vote

### Calculate and interpret the instantaneous frequency

Wow, what a huge question. I'm going to answer the not-so-important question first: And one last, not so important question, why is it that most papers I find on instantaneous frequencies are from ...
• 22.5k

Only top scored, non community-wiki answers of a minimum length are eligible