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Can a hill 20-25 km from a cell tower reflect a signal to an antenna 2.5 km away? I get the best signal pointing a yagi at such a hill.

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I'm still working on getting a Bell signal into my rural place (ref this post). This is a Turbo Hub (Ericsson W35) for both phone and internet with an external antenna and signal booster. I've changed the antenna from a dual-frequency (800Mhz+1900MHz) Wilson to a straight 800 MHz yagi because the nearest tower uses 850 MHz.

Signal has improved nicely, but the antenna still points away from the tower - pointing towards the tower gets no reception. The antenna is pointing towards a large hill about 2.5 KM away. It's the tallest hill in the area - peak is about 400m. It's dome shaped and covered in forest. It's crown land and there's no tower on it. The closest cell tower is about 25 km away on top of a hill that's 360m high. The terrain between the tower and the 400m hill is hilly, but nothing higher than the hill the cell tower is on, so the 400m hill should have a decent line of sight to the tower.

My place is at 260m on a direct line between the tower and the 400m hill. I have clear line of site to the hill over a lake. According to the the cell tower map, the next closest tower is on a 200m hill 90 degrees of the current direction with lots of 300m hills between it and me, so I don't think any reception from that is likely. The nearest tower in the direction the yagi is pointing is 1.5 hours drive away - there's a large coverage hole - so I can't see picking up any signal from there. And my LD records show calls originating from the town close to the local tower, so I'm confident that's the tower I'm using.

So can that hill bounce a signal that well? I wouldn't have thought so, but my evidence seems to suggest otherwise.

FYI, I am getting 1.75-2.50 Mbps down and a 0.50-0.80 Mbps up with the current setup. Quite decent - beats the satellite internet service I was using, and cheaper, and none of the latency issues.
 

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Many things can reflect a signal. Many FM radio listeners and analog TV viewers experience it as unwanted interference called "multipath". With FM, it causes distorted audio and TV gets ghosting. In remote areas, "billboard reflectors" are sometimes used to get microwave signal to go a bit further or around an obstacle. The company I used to work for, many years ago, used one to get microwave from Sudbury to Capreol. The reflector was on a hill just north of Capreol, which didn't have line of site to Sudbury. The microwave dish at the Capreol office pointed to that reflector, which was in the opposite direction of Sudbury.

So, yes, it is possible for a hill or other structure to reflect a usable signal.
 

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you also have to understand signals are not always "line of sight" just because you see the tower does not mean it will be the strongest,, signals can have a peak at a different direction sometimes i get a stronger signal when i move away from a tower than right at it, due to the curvature of the wave..
 

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Thanks for the replies.

The billboard reflector makes sense to me, but the hill wasn't a nice flat surface like that, so I wasn't sure it would reflect the same. It's dome shape and it's forest cover led me to think it wouldn't bounce a signal back to me that well. It seems it does the job well enough.

I put the antenna pole on the side of the house closest to the cell tower, which means my yagi points across the roof when pointing at the reflecting hill. Should I try to move the antenna pole to avoid this?
 
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