Digital Phase Modulation baseband or passband?
Assuming $g(t)$ is a baseband signal, $s_m(t)$ is passband. You can see that it is by multiplying the two complex exponentials, expanding the result into sine and cosine terms, and then taking the real part.
An interesting thing about PSK signals is that they are an example of quadrature modulation, and in consequence, you can represent them either as real passband signals, or complex baseband signals. If you assume $s_m(t)$ is a PSK signal, and given that it is real, it must also be passband.