Slotted Wavguide Antenna - RF Cafe Forums

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crash66429
 Post subject: Slotted Wavguide Antenna
Posted: Thu Aug 14, 2008 11:31 am 
 
Lieutenant

Joined: Tue Jul 15, 2008 11:35 am

Posts: 2

I have been tasked with building a slotted waveguide antenna for the X-Band. As this would be my first attempt, I would appreciate any words of wisdom, tips, tricks or material recommendations. So far I plan on slotting the WR90 which will be soldered to a choke flange. That will connect to the cover flange WG to SMA connector. Thanks!
 
   
 
nubbage
 Post subject:
Posted: Fri Aug 15, 2008 6:03 am 
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm

Posts: 218

Location: London UK

Hi crash

I was on a Sperry team designing and building these for marine radar at 9375MHz many years ago. The milling of the edge slots (or as well the broadside slots) is quite critical in order to keep the gain up and the sidelobe level low. Also you need to consider the array illumination function most appropriate for your application. This might be Tchebychev, cosine-on-pedestal etc each of which has a specific beamwidth and sidelobe level characteristic.

I have a few designs ready-done (by others) for 10.3GHz.

What are your design criteria, like operating bandwidth, gain, sidelobe level, polarization etc?

Is this a student project or a commercial product?
 
   
 
crash66429
 Post subject:
Posted: Thu Aug 21, 2008 11:12 am 
 
Lieutenant

Joined: Tue Jul 15, 2008 11:35 am

Posts: 2

I am reverse engineering an existing functional antenna. It was done as a student project at the masters level. The student has moved on and left us with only the physical antenna. It is being use for the testing of a commercial airborne SAR prototype. I need to reproduce the antenna and later possibly make improvements.

The operating BW is 500MHz centered at 9.75GHz. I believe the beamwidth is 30 degrees. The configuration is a linear longitudinal shunt slot array. I do not really have all of the other design parameters at hand. That's what I have been able to determine so far. Thanks for your input!

Posted  11/12/2012