5.8GHz FHSS telephone
I've got one of the newer Panasonic 5.8GHz FHSS telephones that has one base station and allows for up to 8 remote phones which can also be used as intercoms. The base station is located in the house. One remote phone is located in the detached garage about 50 ft. away. The garage is embedded into the mountain-side downhill from the house with one wall made of cement and the other 3 made of wood. There are two windows plus the 6 windows in the garage doors themselves. That remote phone works just fine. Another remote phone is located in a shop about 30 ft away, uphill. The shop has no windows and a metal door. The remote phone in the shop barely works, until I ***** open the door a couple inches.
So here's my questions(s):
Am I right in thinking that the 5.8GHz signal doesn't penetrate walls, but instead reflects? Does the phone located in the garage (which works well) work due to the fact that there are windows? If this is correct, then is there something that would work better than a window to allow the RF signal inside the shop, or is a window the best solution?
Oh yeah, I have tried swapping remote phones to confirm that I didn't have a bad phone.
Thanks much.
Hi,
Am I right in thinking that the 5.8GHz signal doesn't penetrate walls, but instead reflects?
Yes, you are right, in most of the cases this is so.
Does the phone located in the garage (which works well) work due to the fact that there are windows?
Yes and you mentioned wooden walls on the 3 sides that may help on kinda "scattering" through of the waves I think.
...is there something that would work better than a window to allow the RF signal inside the shop, or is a window the best solution?
Well, maybe, but building a window is usually more expensive than doing the followings:
If you could build a (receiving) antenna for 5.8GHz and place it on the roof of the shop, pointing to the house because this way you can collect useful EM field from the base station. And you lead the cable coming from the Yagi into the shop and connect it to a similar antenna that radiates equally inside the shop. This inside antenna would be driven by the antenna signal from the outside antenna, right?
Now the question is whether you can relatively cheaply buy or maybe construct antennas for 5.8GHz? Also the coaxial cable (that would connect passively the two antennas) is involved by its cost at such a high frequency.
At the moment I do not know commercially built antennas for 5.8GHz because I have not searched for it yet. I know of amateur radio constructors using the 5GHz band for communication, so there must be solutions. Have a search if you feel like this idea. This solution is called passive signal translation when you are in a valley and place such antenna pair on the mountain peak, one antenna receives a television channel (or channels) and drives the other antenna next to it which points downwards to the centre of the valley where your house (or a village) is.
Regards
unkarc
It's been MANY years since I did any RF work, and never at this high of freq. I wanted to make sure I was on the right track. I really wasn't sure how glass in a window propagated 5.8GHz signals, but it's the only explanation I could come up with.
The use of a passive repeater had crossed my mind too. I think I'll look into building a pair of 5.8GHz antennas. Unfortunately I don'y have any equipment that goes that high, so I won't know how well the home-made antennas are performing. I did a brief search for antennas and found some in the S25 to S100 price range, but I think I'll try home-made first.
Thanks.
Hi,
OK, and here is link to read some good info on this topic:
http://www.users.bigpond.com/anvdg/MICROWAVE%205GHz.doc
I do not think a problem you are lacking (measuring) equipment for this 6cm band (and by now I know the amateur band is at 5760MHz and not at 5GHz as I wrote).
Because a parabolic dish or a horn antenna for instance has wide bandwidth and high gain: there is plenty of output to loose from... I mean there is no real need for exact measurements in your case.
Maybe a good idea to look for ham (amateur) radio operators near your residential area, even a used dish would serve your purpose or a second hand satellite dish also.
unkarc
Thanks for the doc. I didn't realize that the feedline was such an issue, just assumed (bad idea) that there was an inexpensive coax out there to do the job. More research...