Can I double up antennas for better performance?

[Mark42]

I am using a panel antenna for transmitting/receiving the 1900Mhz signal used by PCS (cell phones and mobile broadband) . The antenna is in my attic, and I know that the walls and roof are reducing the gain. When I have the antenna outside, it sends a -10 greater signal than when indoors.

I could mount the antenna outside, but it needs to be high on the house, and in an area that is very dangerous for me to be climbing on a ladder. Plus it is much safer for me to be working in the attic, and the equipment is less prone to be struck by lightning, or damaged by exposure to the elements.

To compensate for having the antenna indoors, can I add a second antenna and connect them together to increase the signal? If so, how is is done?

 

[i386]

Re: Can I double up antennas for better performance?

I'm not sure how that would work Mark. How close are you getrting to the advertised maximum speed now?

 

[gonefishie]

Re: Can I double up antennas for better performance?

It won't work if they're both inside, 2 deaf ears don't make a good one. Why don't you just drill a hole in the wall, stick the antenna out and then seal the opening with caulk. Make sure you run a ground wire to the dirt to dissipates possible lightning strike.

 

[Mark42]

Re: Can I double up antennas for better performance?

I could put it on a mast and have it mounted outside. But it means being on a ladder that is on the roof of the garage to reach the second floor of the house facing the cell tower. I don't do well on sloped surfaces like roofs because one of my ankles doesn't bend sidways anymore. And I have to have a ladder with adjustable legs for the slope, or build a temporary flat surface to put the ladder on, etc. That is getting too dangerous for me. I would rather just work in the attic.

 

[gonefishie]

Re: Can I double up antennas for better performance?

couldn't you go up in the attic and drills from the inside? Might requires some crawling but no climbing.

 

[JCF350]

Re: Can I double up antennas for better performance?

Don't know if it applies to this but side by side CB antennas makes them directional. IE: One on each side of the cab extends the range up the road.

 

[Hoss the Hermit]

Re: Can I double up antennas for better performance?

Don't know if it applies to this but side by side CB antennas makes them directional. IE: One on each side of the cab extends the range up the road.

Works on CB, but only extends range. As far as incresing signal strength at fixed range, I don't think it will help. The other thing is, unless the antennae are perfectly matched, you may very well see a decrease in signal. Not 100% sure, but don't think it's gonna help ya. Possibly an amplifier (signal booster) might be worth looking into, I've heard positve reports from some people, negative from others.

 

[mscher]

Re: Can I double up antennas for better performance?

I could put it on a mast and have it mounted outside. But it means being on a ladder that is on the roof of the garage to reach the second floor of the house facing the cell tower. I don't do well on sloped surfaces like roofs because one of my ankles doesn't bend sidways anymore. And I have to have a ladder with adjustable legs for the slope, or build a temporary flat surface to put the ladder on, etc. That is getting too dangerous for me. I would rather just work in the attic.

If the reception is that much better outside, it may be better to nix putting it in the attic, swallow some pride and throw a few bucks at an able bodied relative, or antenna pro (if they still exist).

Antenna reception in the attic usually stinks, unless the signal is pretty strong.

good luck.

 

[Xcusme]

Re: Can I double up antennas for better performance?

How much antenna cable are you using?? Where's the router located?

 

[Nandy]

Re: Can I double up antennas for better performance?

is that -10 really making a big difference in your speed? Check that first before you go all this trouble.

 

[dave11]

Re: Can I double up antennas for better performance?

JCF350 is right. The only thing that two joined or co-phase antennas will do is make your transmission directional.

 

[rwise]

Re: Can I double up antennas for better performance?

it will also make reception directional, coax would need to be cut in 1/4 (1/2, 3/4, or full) wave lengths, spliced etc.

Can you open the wall from inside the attic and mount it outside, safely? Or maybe take out a vent long enuf to do the job at hand?

 

[wavrider]

Re: Can I double up antennas for better performance?

Two antennas are caled co-phasing. It does increase reception but does not increase transmission.

Co-phasing requires an harness to match the impedience so you do not have a high vswr.

What would probaly be more efficient and not require you to climb on the roof is a parabolic antenna. simple to build requiring a little soldering experience.
Google a search for can antenna, follow the formula's and see what you think.
I have one in operation made out of an old primestar sattelite antenna and a tomato soup can, my neighbor is using it to ride off of my wireless lan I have set up and he is over 800 feet away from me.
This type of parabolic antenna has been tested to work on distances over 12 miles, highly efficient. Good luck.

 

[Xcusme]

Re: Can I double up antennas for better performance?

Like this, I'll bet http://people.wallawalla.edu/~Rob.Frohne/Airport/Primestar/Primestar.html I modd'ed another type and it worked just fine... http://www.angelfire.com/ok3/xcusme/index.html

 

[Mark42]

Re: Can I double up antennas for better performance?

is that -10 really making a big difference in your speed? Check that first before you go all this trouble.

It should. Every 3db in gain doubles the strength of the signal. The stronger the signal, the faster the connection will be (up to a point). If I get the signal into the -60's that is about as good as can be expected here. And it should give me a consistant 1.4 to 1.5 meg connection speed.

The panel antenna I have is 11db, (13dbi), and is only about 11 inches square. To get a higher gain antenna I have to get a big grid antenna rated 25db (at higher cost). I'm already breaking FCC rules by hooking up the 11db antenna to my amp!

I was outside and counting the vinyl siding sections to figure out how high the attic floor is above the garage roof when, I realized I can mount an antena mast to the side of the house by just standing on the roof of the garage without using a ladder. I can drill the hole from the attic and feed the cable out, caulk from the outside and raise the mast.

If I do that, I'll mount the amp and router on the ceiling of a closet that joins the outside wall and that will cut the length of antenna cable in half. I can also go up a size, and that should only result in about -1.5db loss due to cable length. Right now I'm losing about -3 db to cable loss.

I'll wait until spring and see how the foliage affects the signal before making any changes.

I like those prime star dish antennas. They are set up for wifi at 2.4mhz, but I'm runing EVDO at 1.9mhz, so I'm not sure how to go about modifying the dimensions to accomodate the lower frequency of mobile broadband. Any ideas?