N900 Cell antenna hack
 

Hello everyone, first post.

I've been a longtime fan of this phone, but finally got one a couple days ago.

I'm using it on the AT&T network. I get almost full 2.5g bars everywhere.. except buildings.

When I walk into any store, my signal drops completely and I have no service. Call, data, etc.

A few questions:
After googling a bit, it seems people are having antenna issues after PR1.2 (1.3?). Would this be causing my problem? Or is it I'm using the AT&T network on a phone not made for it? Or could it be something wrong my specific model?

Also, are there any hacks to increase the antenna size of the cell portion of the phone? Is this possible? Would it make a difference? I'm pretty good at doing custom mods on small devices, just never a cell phone antenna.

Thank you

Re: N900 Cell antenna hack
 

this is a network issue, and affects all GSM networks. GSM is notoriously poor at penetrating buildings.

Re: N900 Cell antenna hack
 

Would increasing the surface area of the internal antenna help alleviate this problem?

Re: N900 Cell antenna hack
 

Re: N900 Cell antenna hack
 

Cell frequencies are very tight. Modding the antenna would be very difficult. I have similar issues in large stores (metal framed mainly), but have always had this problem, with every GSM phone I've owned. It's pretty much a given.

Some stores (mainly tech stores, like BestBuy or the like) are becoming smart to this and placing a repeater in the center of the store (inside) with an antenna drilled through to the roof. It may be worth mentioning it at the service desk if it's a large store that frequents tech customers. They only cost about $300, and pennies to operate, which for a store that wants people to stay in their store and shop, is a small price to pay. Most store managers just don't know it's an option.

Re: N900 Cell antenna hack
 

I don't know what You know, but in smartphones there are multiband antennas. You'll rather destroy the whole thing trying to modify antenna.
Leave as it is unless You REALLY know what You are doing.

Re: N900 Cell antenna hack
 

Thank you for your replies. I'm not going to attempt something like this. I forgot about Apple's antenna problem. If they can't do it, I sure can't.

Re: N900 Cell antenna hack
 

The higher the frequency the more 'line of sight' a signal becomes. I don't like to generalize, though in the more affluent countries the public find cell antennas to be an eye-sore, many also assume a cancer risk is present so there is a tremendous amount of lobbying to minimize the number.

Here in Asia there are cell antennas everywhere, including inside most larger buildings. I don't recall ever having lost signal, dropped calls are also quite rare.

Like others have said, don't mess with your antenna without doing a bit of math beforehand. The tolerances above 900MHz become quite important.

I would suggest this is a telco issue rather than anything to do with the N900 at all.

Edit: Apologies amgine, I just saw your last reply, you're not going to do it :-)

Re: N900 Cell antenna hack
 

STUPID POST the author can put that it is a question

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Re: N900 Cell antenna hack
 

As dchky points out the higher the frequencies are the more directional; they become and as we are talking about the 850/900/1800/1900 mhz/ghz cell phone frequencies they don't get much higher than that.

Woody is spot on when he talks about repeaters as this is the only real way of sustaining network coverage at that high in the spectrum as transmissions are very much "line of sight" and only takes a bit of metal to stop it dead in its tracks and also does not travel through thick walls too good hence why we get little or no signal inside a building especially in a built up area.

Incidentally it is a great shame that the cell network didn't win the 700mhz part of the spectrum as it would have meant much better and further signal transmission area's.

If we had vhf then there would be no problems at all but antenna size would be much bigger, oh well the joys of uhf and above.

Repeaters are the only way forward because to make a quad band dipole antenna would need very low noise in line amps and no mobile has anywhere near the space for that kind of antenna, we are stuck with a basic 0db gain antenna but would be nice to have enough space to mount better gain antenna's, a tremendous amount of work involved even for anyone who knows anything about high gain antenna's.