My neighbor is a Class 8 truck driver and he recently put up what appears to be a large antenna outside of his house. I assume it is an antenna for radio - sorry, I am not technical and I just moved here. Can the antenna cause static on cell phone calls? Phone works great .5 miles down the road, but not at my house or next door.
$\begingroup$
$\endgroup$
0
Add a comment
|
2 Answers
$\begingroup$
$\endgroup$
7
If the static is constant, it's not caused by an amateur radio antenna, as those at most are 50% transmit and usually much much less.
Also, legally under FCC part 15 regulations in the US, a consumer device must not be affected by things like this.
Also, most phones these days are digital, and digital phones don't get static, they would get drop outs where the audio cut out completely or the call is dropped. And if you have an analog phone (do those even exist anymore?) and were getting interference from another transmitter, you would hear buzzing, not static.
There are many other possible causes of static, including loose connections to the speaker in the phone, noise at the cell site, noise on lines between the cell tower and whoever you are talking to, etc... On an analog phone, static could be caused by having a weak signal.
If the static goes away when you change locations, possibly you are switching to a cell tower that is closer to the new location, and the one near your house has a problem.
-
$\begingroup$ There's also just the dreaded deadzone... There's a 1/2 mile section of highway not far from me where you have 5 bars before it, 5 bars after it, but in that area, all calls drop. $\endgroup$– David Hoelzer ♦Commented Jan 24 at 1:06
-
$\begingroup$ Dead zones are likely caused by elevation dips, in the hole you can't see out. But it can also be caused by multipath propagation (aka fresnel zones), but those are usually small in size, on the order of 1/2 wavelength, so moving around a small bit would recover the bars. (I suppose dead zones could also be just bad tower coverage.) $\endgroup$ Commented Jan 24 at 1:11
-
$\begingroup$ Modern cell phones are not very susceptible to multipath problems - cdma2000/umts already had equalizers, and 4G onwards is interently designed to deal with multipath. This works basically because the bandwidth of a single cellular channel is large enough so that there's not just one wavelength that could get completely cancelled. Also, mimo. $\endgroup$ Commented Jan 24 at 2:22
-
$\begingroup$ And I'd be surprised if you can instruct a modern smart phone with unmodified firmware and without vendor tooling to switch tower explicitly. These things are petty good at choosing the best connection partners (cells) automatically, and do that, if necessary many times a second $\endgroup$ Commented Jan 24 at 2:24
-
$\begingroup$ Agree on both points, Cell probably has enough antenna diversity to ignore fresnel/multipath. I wasn't implying you could choose a tower, I was implying that moving far enough is likely to trigger a tower change automatically. $\endgroup$ Commented Jan 24 at 2:26
$\begingroup$
$\endgroup$
If a trucker erects a "large" antenna above his house, it is for citizens band radio which is ~27 megahertz (wavelength of order ~11 meters) with amplitude modulation in which the carrier and one sideband are suppressed i.e., SSB mode, and limited to 5 watts of transmit power unless you live in Arkansas where the CB transmit power limit is 50,000 watts (just kidding).
Interference between 27 MHz SSB analog signals and digital cell phone signals will be negligible, and even then could only exist while the citizens band transmitter is actively broadcasting a signal which only happens while the CB transmitter is keyed ("ten-four, good buddy, catch ya on the FLIP-FLOP!!!").
So any interference would cut in and cut out on a time scale of order ~a minute, which you would notice immediately.
