Controllers understand static?

[rc300xs]

I have noticed something.  The control tower will transmit and you can hear clearly.  Then the aircraft transmits back and all you hear is static and a very faint hint of a voice.  How does the tower possibly understand the aircraft?

I have noticed this on LiveATC as well as on my scanner in the truck. 
Note: It doesn't seem to matter that I am sitting 1 mile away from the tower in my truck.

[MathFox]

Antenna location makes a great difference; VHF communications are "line-of-sight" and when you are in a truck in front of the terminal building, it will be hard to hear the planes behind the building. There also is the issue of "electric noise"; some types of lamps, computers, other electronics and car ignitions generate noise... placing the receiver antenna strategically away from these sources of noise, silencing the sources of noise, etc. gains you several dB. It is possible that ATC uses transceivers at places several miles from the airport to obtain better communication using cables to connect the signal to the tower
Next there is the issue of antenna quality and receiver quality. Antennas on hand-held scanners are a compromise for portability, connecting a proper full-size antenna makes a lot of difference. At last, professional receivers are more expensive and that is partly because they are more sensitive and have lower internal noise levels. So, it is likely that the controller hears a voice with some noise behind it...

Hmmm, I forgot to mention that controllers are pros and trained to get infornation out of lousy radio connections.

[KSYR-pjr]

How does the tower possibly understand the aircraft?

Most likely the transmission is not static to the controller.   As MathFox pointed out, it is more probable that the reason for the static has to do with the feeder's proximity to the transmitting aircraft, and in your case it has to do with the quality of your handheld.   

ATC transmitting/receiving towers are just a bit better quality than your handheld. 

[Gecko1]

I have noticed that even with a base, aircraft approaching from the far side of the tower sound staticy or are squelched out, while the controller may hear them fine, since they are in the center of the transmissions radius.

You should look at a sectional chart. Notice the circular radius around the tower. Now draw a radius around you that corresponds to your range, it should include the tower, if you can hear it. Notice there are some places in the controller's radius that are not in your radius. If there are planes transmitting in these places, they will be hard for you to hear, but the controller will hear them fine.

[MathFox]

I have noticed that even with a base, aircraft approaching from the far side of the tower sound staticy or are squelched out, while the controller may hear them fine, since they are in the center of the transmissions radius.

The original poster didn't mention whether the planes are on the ground or in the air. A lot of LiveATC feeds have problems receiving the planes on the ground, bad line of sight. The tower has (is) a far better antenna position for ground ops.

[rc300xs]

The planes are in the air.

Thanks so much for the feed back.  It makes sense to me now.

I would bet that the tower transmitter uses a higher wattage as well?

Thanks again