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RF antenna theory

There is little point in learning about RF scanning and coordination if you don’t understand how sending and receiving antennas work. I don’t currently possess that information. I have a general idea but it’s already clear that I need a better foundation. For the last week or so since I dove head first into RF, I keep recognizing similarities between transfer functions and RF. I’m actually beginning to think that RF is much more difficult to grasp and do well. This is good news. Who would think that sound system design and optimization could be considered “easy” in comparison to another aspect of professional audio? What is becoming obvious is that there are many parallels between the two concepts. Both deal with frequency, wave length, time, constructive and destructive interference, phase, etc… Both use tools to visualize what we cannot see with our eyes. One uses and RF scanner & the other uses a measurement mic and transfer function. Different ranges of the same electromagnetic spectrum.

I won’t be surprised if learning more about RF actually answers some of the questions I still have about sound system design and optimization. One can hope.

Most of us in the live audio realm deal with RF mics and I’d be willing to be bet that many of us have only a slight understanding of how the technology actually works and how to optimize the hardware. “RF coordination and optimization”.

Properly using RF gear and coordinating your frequencies is a fairly straight forward process. Understanding sending and receiving antennas is the final frontier of optimizing RF. Get it right and your rig is artifact free. Get it wrong and your event is ruined.

The industry has a few antenna types that we need to know about if we’re going to pick the right antenna / antennas for the job.

HELICAL:
Professional Wireless Services – Helical Antenna
RF Venue – CP Beam

DIVERSITY FIN
RF Venue – Diversity Fin

LPDA (Log Periodic Dipole Array)
Lectrosonic – LPDA (Log Periodic Dipole Array)

Here is great article by Volker Schmitt & Joe Ciaudelli of Sennheiser:
prosoundweb.com – Understanding Wireless : Positioning Antennas For Trouble Free Transmission

Here is a white paper explaining how the Diversity Fin design works provided by RF Venue:
The Diversity Fin Antenna and Polarization Diversity for Wireless Microphone Applications

Here are some links to RF Venue’s Alex Milne’s blog.
RF Venue blog – Understanding the Difference and Debunking the Myths Between Active and Passive Antennas
RF Venue blog – What is ERP?
RF Venue blog – Polarization, Polarity and Polar Pattern: What’s the Difference?