Hey,

In fact, the mapped complex symbol will go into two parts, that is,

the real part and the image part will modulate the cos(w_c * t) and

sin(w_c * t), separately.

E.g., complex symbol is denoted, y = a+jb = r*cos(theta) +
j*r*sin(theta);

so, a*cos(w_c * t) - b*sin(w_c *t)
= r*cos(theta)

*cos(w_c * t) - j*r*sin(theta)

*sin(w_c * t)*

= rcos(w_c * t + theta)

= r

This is the final transmitted real signals, where w_c is the carrier

frequency, shown in Gnu radio as well.

yup…got it…thanks…

i understood in QPSK how the bits get mapped to constellation space.

One doubt still persists.QPSK modulation theory tells us that we need to

change the phase of the carrier depending upon the incoming data

bits…i.e what we see mapped to the constellation space is the modulated

data.

I cannot see a carrier frequency specified anywhere in bqpsk.y…Where do

i specify the carrier frequency for my transmission…this part is still

a bit hazy…

I can see the incoming bits getting mapped to constellation space not

the modulated data…M i missing something here?

## Thanks

ManavPosted via http://www.ruby-forum.com/.

Regards,

Robert