Qpsk modulator

342

04:16:33

After the BPSK modulator, I present you the QPSK modulator.
How it works :
First, a square signal is generated at 4 time the frequency of the carrier. It's injected in a shift register.
The output of the shift register is 4 square signal dephased by 90°. They are the filtered (value of L and C are not optimized, 'cause, you know, 470uH is quite big).
Then the phase is selected using an analog mux/deux. OpAmp is optional 
The whole circuit can be made using only two IC and a few passive components.
PS : simulation is damn slow on my phone

published 8 years ago

zorgrian

8 years ago

There should be a prize for the slowest simulation

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.