HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Sep 13, 2010, 12:14 AM
Registered User
Joined Jul 2010
63 Posts
Discussion
Base tracking patch antenna on top of the Quad!?

Why not?

You have these tracking antennas that allow you to increase the range by tracking your plane with a directional gain antenna.

Why wouldn't you be able to do this also on the Quad side, an Oktokopter for example should be able to hold the weight easily. Probably have to hang it under the kopter. To the electronics it doesn't make a difference whether it is the plane moving or the base station, does it? You could send video much further since that is the bottleneck..

Has anyone tried this?
adbo is offline Find More Posts by adbo
Last edited by adbo; Sep 13, 2010 at 12:20 AM.
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 13, 2010, 06:36 AM
Suspended Account
Long Island, New York
Joined Jun 2008
6,428 Posts
The reciever antenna sensitivity is the most import part of a TX and RX system. You are better off with an Omni antenna on the TX of a moving platform and a higher DBI antenna on the tracking GS. IMO.
Directional antennas are big and you would need servos to operate them. Not to mention the added complexity of keeping a moving antenna pointed at a fix position. Stationary tracking systems have bugs, I can only imagine what issues you would have with a 8dbi patch on an Octo.
Tarro is offline Find More Posts by Tarro
Reply With Quote  (Disabled)
Old Sep 13, 2010, 09:40 AM
Registered User
bob4432's Avatar
United States, AZ
Joined May 2010
1,820 Posts
why not just use the same setup on a quad and let the base antenna move to track the quad?
bob4432 is offline Find More Posts by bob4432
Last edited by bob4432; Sep 13, 2010 at 10:19 AM.
Reply With Quote
Old Sep 13, 2010, 10:02 AM
LOAD "FLIP-FPV",8,1
vic20owner's Avatar
Joined Sep 2006
3,943 Posts
There is no reason to put a patch antenna on the vehicle. It's easier to point the patch in the general direction of the vehicle than it is to constantly point the moving/rotating vehicle at the base station.
vic20owner is offline Find More Posts by vic20owner
Reply With Quote
Old Sep 13, 2010, 10:35 AM
Registered User
Joined Jul 2010
63 Posts
You would then have a patch antenna for the video on both sides of course. If you win a lot by using it at the base then you win just as much again by doing it on the sending side, right?

A base tracking patch antenna should be able to keep up with a decent behaving quad I would think?

(Absolute beginner here obviously, just got my brand new Oktokopter to fly for 11 minutes with an extra kilo on top of a 5000mAh lipo, 20 minutes normally. And then I let it cut me..ffffk. Sanding the sharp residue plastic from the props is a good idea, just in case..)
adbo is offline Find More Posts by adbo
Last edited by adbo; Sep 13, 2010 at 10:55 AM.
Reply With Quote
Old Sep 13, 2010, 01:24 PM
LOAD "FLIP-FPV",8,1
vic20owner's Avatar
Joined Sep 2006
3,943 Posts
I would recommend going to the FPV forum, and reading up on antenna gain patterns.

A 500mW transmitter, a patch antenna on the receiver, and a simple 3dbi gain antenna on the aircraft will give you far more range than your rc transmitter will operate.

Also, you will need a HAM radio license if you are in the USA.
vic20owner is offline Find More Posts by vic20owner
Reply With Quote
Old Sep 13, 2010, 05:27 PM
Registered User
bob4432's Avatar
United States, AZ
Joined May 2010
1,820 Posts
Quote:
Originally Posted by adbo View Post
You would then have a patch antenna for the video on both sides of course. If you win a lot by using it at the base then you win just as much again by doing it on the sending side, right?

A base tracking patch antenna should be able to keep up with a decent behaving quad I would think?

(Absolute beginner here obviously, just got my brand new Oktokopter to fly for 11 minutes with an extra kilo on top of a 5000mAh lipo, 20 minutes normally. And then I let it cut me..ffffk. Sanding the sharp residue plastic from the props is a good idea, just in case..)
have a look at this thread for some serious range for a quad - http://www.rcgroups.com/forums/showthread.php?t=1147430
bob4432 is offline Find More Posts by bob4432
Reply With Quote
Old Sep 13, 2010, 06:01 PM
Suspended Account
Long Island, New York
Joined Jun 2008
6,428 Posts
Quote:
Originally Posted by adbo View Post
You would then have a patch antenna for the video on both sides of course. If you win a lot by using it at the base then you win just as much again by doing it on the sending side, right?

A base tracking patch antenna should be able to keep up with a decent behaving quad I would think?

(Absolute beginner here obviously, just got my brand new Oktokopter to fly for 11 minutes with an extra kilo on top of a 5000mAh lipo, 20 minutes normally. And then I let it cut me..ffffk. Sanding the sharp residue plastic from the props is a good idea, just in case..)
Your getting 20 minute flights from a single 5000mah battery? What does your Octo weigh?
Tarro is offline Find More Posts by Tarro
Reply With Quote  (Disabled)
Old Sep 13, 2010, 06:04 PM
Registered User
Joined Jul 2010
63 Posts
I saw the long range threads and I am not really interested in doing that. Just wanted to know if there is any reason why it couldn't work?

You could in theory do that for both the Video Tx and the Radio Rx. I just thought a quad is a different platform that can do thing normal planes can't. How much range difference could it make?

Then of course battery would become the bottleneck, you never come back.. but let's ignore that..
adbo is offline Find More Posts by adbo
Reply With Quote
Old Sep 13, 2010, 07:15 PM
$#|+
mkmkmk13's Avatar
United States, CA, Orange
Joined May 2007
1,605 Posts
You would need a compass for heading
Gps can tell ur heading if ur moving forward but if u stop the quad won't know where home is and it wouldn't aim the patch right
Since patch antennas have high gain, if the antenna points the wrong way u will lose video
I thought about putting a patch on the bottom and aiming it straight down for a high altitude platform but I would need 2 circular patch antennas
mkmkmk13 is offline Find More Posts by mkmkmk13
Reply With Quote
Old Sep 14, 2010, 07:46 AM
Registered User
Joined Jul 2010
63 Posts
The mikrokopter has a pretty exact compass,

You'd want enough spread of the signal for some banking, but then again with the telemetry view in Google earth and Hight hold you'd be pretty sure where you are anyway, a few second loss isn't that bad is it?
adbo is offline Find More Posts by adbo
Last edited by adbo; Sep 14, 2010 at 07:57 AM. Reason: well...
Reply With Quote
Old Sep 14, 2010, 07:56 AM
Registered User
Joined Jul 2010
63 Posts
Guess the mikrokopter itself could be the tracker, always setting its backside in the direction of the base.

You'd need a flexible fpv cam so you can keep looking in the direction of flight..
adbo is offline Find More Posts by adbo
Last edited by adbo; Sep 14, 2010 at 08:13 AM.
Reply With Quote
Old Sep 14, 2010, 02:33 PM
Registered User
Joined Jun 2009
291 Posts
You'll want to have an aux omni antenna on the a/c anyway, in case the patch servo goes down. That spells heavy.

Pros: a few measly dBs of gain that you're not gonna use anyway since you have to stay LOS.

Cons: cost, low reliability, extra time you put in it, weight, power consumption.

Is it worth it?
tori3 is offline Find More Posts by tori3
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Mini-HowTo Fast Patch - IBCrazy's easy DIY patch antenna IBCrazy FPV Talk 309 Nov 26, 2014 05:50 AM
Discussion Base station tracking ziomatrixacs FPV Talk 6 Aug 25, 2010 07:38 PM
Sold Berg 7P top load receiver with base loaded antenna Greg Gimlick Aircraft - General - Radio Equipment (FS/W) 0 Feb 14, 2010 12:42 PM
Discussion 8dbi 900mhz patch antenna on ebay fpvdavid FPV Talk 2 Nov 07, 2009 08:09 PM
Discussion Patch antenna put on car top tungym FPV Talk 2 May 21, 2009 12:01 PM