Real-time loop gain and bandwidth measurement of phase-locked loop

Area of Science:

• Electrical Engineering
• Control Systems
• Signal Processing

Background:

• Phase-locked loops (PLLs) are critical components in modern electronics for signal synchronization and frequency synthesis.
• Accurate measurement of PLL performance metrics like loop gain and bandwidth is essential for system design and validation.
• Existing methods for measuring PLL parameters can be complex or require interrupting the loop's operation.

Purpose of the Study:

• To introduce a simple and reliable technique for direct, real-time measurement of PLL loop gain and bandwidth.
• To enable measurement of the closed-loop gain of a PLL without breaking the locking state.
• To provide a method that can be extended to various PLL systems needing precise parameter assessment.

Main Methods:

• Development of a novel measurement technique for real-time PLL parameter analysis.
• Experimental validation using an actual phase-locked loop system.
• Theoretical analysis to confirm consistency with experimental outcomes.

Main Results:

• Demonstrated a simple and reliable method for directly measuring PLL loop gain and bandwidth in real time.
• Confirmed that the technique allows for measurement without disrupting the PLL's locked state.
• Showed strong agreement between theoretical predictions and experimental results.

Conclusions:

• The proposed technique offers a simple, reliable, and non-disruptive approach to measuring PLL loop gain and bandwidth.
• The method's validity is confirmed through theoretical analysis and experimental validation.
• The technique is readily adaptable for precise loop gain and bandwidth measurements in diverse PLL applications.