Register to reply

Phase-Lock-Loop vs Injection Locking

by Fischer777
Tags: injection, locking, phaselockloop
Share this thread:
Fischer777
#1
Apr24-14, 11:57 PM
P: 81
Sorry it's been a while since I posed here. I'm working on a project for school that will involve sending a synchronizing signal to an oscillator on a reciever, which I know often uses a phase-lock-loop. However, I was doing some reading on injection-locking, and it seems that it would be easier to utilize than a circuit involving several mixers, filters, and variable reactance components. But dispite this I can't find any instances where it's used in a practical circuit, so it somehow seems to be less preferable than PLLs. I'm wondering if anyone knows why this is the case (why PLL are prefered over injection-locking).

Thanks!
Phys.Org News Partner Engineering news on Phys.org
Tiny UAVs and hummingbirds are put to test
Britain to trial driverless cars from 2015
NIST corrosion lab tests suggest need for underground gas tank retrofits
Baluncore
#2
Apr25-14, 12:32 AM
Sci Advisor
Thanks
P: 1,772
Injection locking will lock the p'th harmonic of an oscillator to the q'th harmonic of a reference signal. Just which integer p/q ratio of harmonics can be hard to control or predict, and sometimes does not matter if drift is the only concern.

A PLL synthesiser has well defined integer ratio p/q, (a swallow counter), that locks a local VCO to a predictable frequency.
Fischer777
#3
Apr25-14, 01:08 AM
P: 81
Okay, thanks! It makes more sense now.


Register to reply

Related Discussions
Phase locked loop with 3 ICs Engineering, Comp Sci, & Technology Homework 15
Optics: What is phase matching, and mode locking Introductory Physics Homework 1
Phase change in lock-in amplifier Electrical Engineering 1
Phase Locked Loop Engineering Systems & Design 7
How to prove that the composition of injection is an injection? Calculus & Beyond Homework 1