Hi Folks,
I have been experimenting with two recently aquired SEXTANTS over the last few days, and they seem to work very well.
I wish to use them to link two non line of sight locations, and I have a third location which is line of sight to both the others, so the setup will look like.
(- and -) reprasent SEXTANT or similar devices.
. . . . is a radio path
’ ’ ’ ’ ’ is a physical connection, eg ethernet
My questionis this.
At the RELAY point I could simply have two SEXTANTS connected via ether net, but this seems rather wasteful in terms of equipment and power (The site will be wind/solar powered). Also we may wish to expand in the future to include a third link.
I would like to try and make up a suiteable setup for the relay point using wifi cards, router boards, and antennas that are equivalent to teh SEXTANTS. What components should I use?
In particular
does any one know what wifi card is in the SEXTANT (I would like to use MIMO)
Which routerboard (ideally with three mini PCI slot in case we need a third link at the RELAY point in the future) is based on the same proccessor etc as the SEXTANT
What would be the best antennas to use at the relay point??
Or maybe there is an already integrated solution for the RELAY point??
With a single routerboard (e.g., an RB433), by the time you buy the radio cards and antennas for this device, you may find that two Sextants are less expensive. Maybe with a third link, a single board would be better, because with three Sextants you’d also need a switch to connect them.
In theory, you could also use one OmniTik as a relay point for two or more Sextants, but I would not recommend it unless you are prepared to accept the performance hit of using the same radio to both receive and retransmit in each direction. Not to mention collisions due to using the same channel, and the increased noise level of omnidirectional antennas. A dedicated radio and (directional) antenna for each link, each operating on a different channel, will give you the best performance.
Hi Hotz1,
Thanks for this. I agree, an omni a the relay point might not be very good. I think this has been called the ‘hidden terminal effect’ in the past.
I might well opt for 2 x SEXTANTS at the relay. But even with two I will need some way of injecting the power, so there will have to be some form of ‘box’ between the two (not just a simple CAT5 cable), and in the case of three, as you say a switch.
Mind you, for ease of installation etc, the SEXTANTS might win.