I am very much interested in this. I have a question on this maybe somebody has experience on xbee. I have fix points Xbee modules say with the claimed 40 mile range and others approaching with 1 mile range. Can the modules exchange data with each other and then what would be the effect if the one module has the a 40 mile range and the others a 1 mile range. I would like to use the long range modules as kind of repeater nodes and the others for tracking asset movement. Then can the one unit use the other units as kind of hopping medium to say I have seen this unit and relay it to the long range repeater unit and act as a carrier when not in range. Then I have very little power available for the low range units. Bascom Avr to manage this effort intelligently Thanks Georg Pistorius
A couple of comments:
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First of all, the “40 mile” and “1 mile” ranges assume line-of-sight and fairly ideal conditions. Buildings, trees, hills and so on will dramatically reduce the range you actually get. Fixed stations with directional antennas will dramatically improve it. Someone here posted some disappointing results in an effort to track buses around a college campus - you might try to find that thread and read it carefully before investing too much time/$ in this.
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To answer your question about units exchanging information, you might need to identify the specific units that you’re talking about. But if you’re willing to put a processor between them, any units can exchange information, of course. You should probably plan to put a processor on each of your “repeater” units.
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When you say “Hopping medium”, I think you’re talking about a mesh network, right? You mean that you want the shorter range modules to communicate with each other to provide a path to the repeater units, if I’m reading you correctly.
Georg:
I am very much interested in this. I have a question on this maybe somebody has experience on xbee. I have fix points Xbee modules say with the claimed 40 mile range and others approaching with 1 mile range. Can the modules exchange data with each other and then what would be the effect if the one module has the a 40 mile range and the others a 1 mile range. I would like to use the long range modules as kind of repeater nodes and the others for tracking asset movement. Then can the one unit use the other units as kind of hopping medium to say I have seen this unit and relay it to the long range repeater unit and act as a carrier when not in range. Then I have very little power available for the low range units. Bascom Avr to manage this effort intelligently Thanks Georg Pistorius
40 mile range: Two ways I know of to do this with unlicensed bands is: Two 900MHz radios such as Digi’s high power 900MHz - XBee isn’t their highest powered 900 MHz radio but might work - we can do the math. Each radio with a high gain yagi antenna. Clear line of sight between the sites. High mounting site for antennas (Fresnel clearance). Another approach is with a pair of MURS band radios (153MHz). Unlicensed. Same line of sight, gain antennas needed at high sites.
Hopping: This can be a simple repeater every distance x along the path, or it can mean a mesh network topology. But mesh in the sense of XBee means DIY or ZigBee, and inter-node distances of 500 ft. or less. BASCOM would be much mor difficult than C or ZBasic (http://www.zbasic.net/forum/ and http://www.zbasic.net/)