slot antenna question


Oguzhan Kayhan
 

Hello all,
I am planning to run the first 10ghz beacon in TA area.
And I am planning to build a slot antenna for this purpose.
While I was digging with example drawings of this antenna, I noticed that on calculations only the wide side of the waveguides computed.

I am planning to build it with aluminum profile. Because I don't have any wr90 wg here. 
Is there any limitation that I should follow on that?
I can choose the wide side according to the cutoff frequency of 10 ghz (around 22mm) but not sure how important the narrow side.

Best Regards

--
73
de TA2NC


KENT BRITAIN
 

Hi  Oguzhan

Do you really need Omni Directional??

Many of our beacons point into the more populated areas.

Thus we use a Sector Horn.   These are far easier to build than slot antennas.

A Sector Horn would have a 90 to 180 deg beamwidth. 

If you let me know the beamwidth you would like, I can work out the dimensions.

Kent  WA5VJB/G8EMY

On Wednesday, October 20, 2021, 03:33:40 PM CDT, Oguzhan Kayhan <oguzhan@...> wrote:


Hello all,
I am planning to run the first 10ghz beacon in TA area.
And I am planning to build a slot antenna for this purpose.
While I was digging with example drawings of this antenna, I noticed that on calculations only the wide side of the waveguides computed.

I am planning to build it with aluminum profile. Because I don't have any wr90 wg here. 
Is there any limitation that I should follow on that?
I can choose the wide side according to the cutoff frequency of 10 ghz (around 22mm) but not sure how important the narrow side.

Best Regards

--
73
de TA2NC


Oguzhan Kayhan
 

Hello Kent,
Thank you for your reply.
You may probably right. I do't think there will be too much need for eastern area of mine so a 180 degree horn might be more than enough.
What about the gain compared to slot antennas on that case?
As far as I know gain of slot antennas is pretty high due to having multiple stacked  antenna design.


On Wed, Oct 20, 2021 at 11:52 PM KENT BRITAIN <WA5VJB@...> wrote:
Hi  Oguzhan

Do you really need Omni Directional??

Many of our beacons point into the more populated areas.

Thus we use a Sector Horn.   These are far easier to build than slot antennas.

A Sector Horn would have a 90 to 180 deg beamwidth. 

If you let me know the beamwidth you would like, I can work out the dimensions.

Kent  WA5VJB/G8EMY

On Wednesday, October 20, 2021, 03:33:40 PM CDT, Oguzhan Kayhan <oguzhan@...> wrote:


Hello all,
I am planning to run the first 10ghz beacon in TA area.
And I am planning to build a slot antenna for this purpose.
While I was digging with example drawings of this antenna, I noticed that on calculations only the wide side of the waveguides computed.

I am planning to build it with aluminum profile. Because I don't have any wr90 wg here. 
Is there any limitation that I should follow on that?
I can choose the wide side according to the cutoff frequency of 10 ghz (around 22mm) but not sure how important the narrow side.

Best Regards

--
73
de TA2NC


--
73
de TA2NC


KENT BRITAIN
 

Here is a photo of a 24 GHz Sector horn.

As shown, it is Horiz Polarization.

I measured 60 deg beamwidth left/right and 11 deg Up/Down
Gain 16.5 dBi   

I have measured dozens of vertical slot antennas.  Very very few have the main beam pointing at the horizon.     

Kent

On Wednesday, October 20, 2021, 04:11:21 PM CDT, Oguzhan Kayhan <oguzhan@...> wrote:


Hello Kent,
Thank you for your reply.
You may probably right. I do't think there will be too much need for eastern area of mine so a 180 degree horn might be more than enough.
What about the gain compared to slot antennas on that case?
As far as I know gain of slot antennas is pretty high due to having multiple stacked  antenna design.


On Wed, Oct 20, 2021 at 11:52 PM KENT BRITAIN <WA5VJB@...> wrote:
Hi  Oguzhan

Do you really need Omni Directional??

Many of our beacons point into the more populated areas.

Thus we use a Sector Horn.   These are far easier to build than slot antennas.

A Sector Horn would have a 90 to 180 deg beamwidth. 

If you let me know the beamwidth you would like, I can work out the dimensions.

Kent  WA5VJB/G8EMY

On Wednesday, October 20, 2021, 03:33:40 PM CDT, Oguzhan Kayhan <oguzhan@...> wrote:


Hello all,
I am planning to run the first 10ghz beacon in TA area.
And I am planning to build a slot antenna for this purpose.
While I was digging with example drawings of this antenna, I noticed that on calculations only the wide side of the waveguides computed.

I am planning to build it with aluminum profile. Because I don't have any wr90 wg here. 
Is there any limitation that I should follow on that?
I can choose the wide side according to the cutoff frequency of 10 ghz (around 22mm) but not sure how important the narrow side.

Best Regards

--
73
de TA2NC


--
73
de TA2NC