×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

802.11 antennas using a splitter

802.11 antennas using a splitter

802.11 antennas using a splitter

(OP)
I have an application where I need to install a repeater, 2.4 ghz 802.11 ethernet radios. I have received conflicting information regarding the use of 2 antennas and a spliter. The radio techs suggest a Omni to Omni on the base run, and adirectional to the omni from the source location, with the comment:
"You should not use an antenna splitter with a half duplex TX/RX signals"
An antenna supplier advises using a splitter with identical antennas & cable length will have about a 3.5 db loss, but allow use of directional antennas at both locations.

Any advice?

RE: 802.11 antennas using a splitter

(OP)
The radio I am using has a repeater funtion, in this case we are trying to establish ethernet for security cameras. The source is below grade (about 100') and 400' from the repeater which is a 15' above the level of the damn. The base radio is 1/2 mile away across the reservoir.

My question is about the use of a splitter with directional antennas, one pointed at the source and the other across the reservoir at the base radio.

The radio techs suggest a Omni to Omni on the base run, and adirectional to the omni from the source location, with the comment:
"You should not use an antenna splitter with a half duplex TX/RX signals"

An antenna supplier advises using a splitter with identical antennas & cable length will have about a 3.5 db loss, but allow use of directional antennas at both locations.

Any advice regarding the use of the splitter?

RE: 802.11 antennas using a splitter

I think I understand, let me explain what I think.
You have the options of one omni antenna, and no splitter, versus two directional antennas with a splitter to connect one base station with a single camera and you have a repeater radio in between the two.


A typical directional antenna if you purchase a standard directional gain at 24 dBi (http://www.radiolabs.com/products/antennas/2.4gig/2.4-aluminum-parabolic.php  only $70), take off 3 dB and you get 21 dBi. Compared to a Terk 12 dBi omni you've picked up 9 dB for your system. (link to a Terk omni http://salestores.com/trendn117.html and under $100). You could try some math to see if it'd work.

I'd say buy the $100 Terk antenna, it's very simple to mount compared to the higher gain antennas and the wind won't blow it around much (I think), put it up and find out quickly if you need more gain. When you do a test trial, change the height of the Terk antenna up and down in increments of 1 inch, bounce off the ground can make ugly results.

What's your range now? Has anyone done some math for you?
 
kch

 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close