Discussion
A coherent detector's local carrier is in error by a phase angle \( \phi \). The recovered output is scaled by
Answer: A
Multiplying the received signal by a reference at phase error \( \phi \) gives an output proportional to \( \cos\phi \), so a small error costs little but a quarter-cycle error nulls the output completely. That is the quadrature null, and it is what a Costas loop exists to avoid. A sine dependence would null at zero error, which is the reverse of the truth. The angle itself has the wrong form, and a squared cosine would describe a power rather than a voltage.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development