Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What is the difference between 4QAM and QPSK and what is I and Q components?

Status
Not open for further replies.

sinnadyr

Member level 2
Member level 2
Joined
Nov 11, 2010
Messages
51
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Visit site
Activity points
1,608
I am writing a thesis on using G3-PLC for power line communications, whereas the G3 standard uses D/QPSK modulation. What I have figured out so far is that both 4QAM and QPSK appearently produces the same waveform, but are they the same matematically?

In a QPSK constellation, are the mapping points at 45, 125, 225 and 315 degrees while the 4QAM is at 0, 90, 180 and 270?

I also struggle to understand the I/Q components of such a constellation diagram. What does "inphase" and "quadrature-phase" actually mean? Is it only other words for real and imaginary part for this type of usage?


Thank you.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top