5.3.2. FPGA-Based QPSK Modulator Example

Try these first

1. 1.

   What does QPSK stand for?

   Hint

   Think about modulation and phase.

2. 2.

   What are the two outputs generated by the QPSK modulator?

   Hint

   They refer to in-phase and quadrature components.

3. 3.

   What does QPSK modulation primarily change in the signal?

   • Amplitude
   • Frequency
   • Phase

   Hint

   Consider what modulation affects in a signal.

4. 4.

   True or False: In QPSK, two bits of data can represent two separate phase changes.

   • True
   • False

   Hint

   Think about the number of combinations two bits can represent.

5. 5.

   Design a VHDL code snippet to implement a 4-QAM modulator and compare it to the provided QPSK modulator.

   Hint

   Focus on how the states change with more bits.

6. 6.

   Simulate the QPSK modulator’s output over time with a specific input data pattern and analyze the phase changes visually.

   Hint

   Utilize software tools that allow signal simulation for phase representation.