Is it possible to interface an embedded board(include a microcontroller like as AVR ) to ultima 3 modem from wi---lan company?
This wireless modems are working at 2.4ghz and 5.8ghz and thier interface port is ethernet 100mbps.The range of this modems is up to 75KM and the antenna is integrated with it.
Please specify the methods for send/receive data with them by a microcontroller system.
sure .. most of wlan modems offers transparent ip connectivity iow ip bridge so try any eth project e.g. ethernut or web51. i also would doubt about range ... espacialy with integrated antennas and allowed erp 20dbm
With 100 M data rate, the range is more likely to be 75 m best case maximum. 802.11 devices with 10 M data rate and 10 dBm of power rarely go 75 m except if they are on two building tops with no obstructions between them.
you can have severel km link but you need to follow some conditions:
direct visinity
externel antennas
a lot of erp ;0)
i saw hop with 26 bdi antennas with distance abt 7km in 2.4ghz 802.11b (10mbps), of cause you have +46dbm erp which is much much more than allowed
at 2.4 GHz the pathloss for 1 km is about 99dB, doubling the distance the loss increase by 6 dB. So for the 75 km the loss should be about 141-147 dB. 75 km is a bit more. In my opinion with the legal ERP and 20-30 dBi antennas is not quite feasible.
They claim 10/100 BaseT data connection. They claim that this product operates on 802.16 protocols. That should give you information on how to make the system work.
Their up to range figures are for free space. Any products that are on buildings will be much more limited. Ground wave is highly attenuative at these frequencies.
once again .. you can use any ip stack project with mcu ... you have to send either tcp or upd packet form your first mcu board to ip adress of your other mcu board. the wireless modems will do the rest for you .. they will bridge your ip networks ...
you can have severel km link but you need to follow some conditions:
direct visinity
externel antennas
a lot of erp ;0)
i saw hop with 26 bdi antennas with distance abt 7km in 2.4ghz 802.11b (10mbps), of cause you have +46dbm erp which is much much more than allowed
i used linksys also .. not problem for longer distances also .. but i needed very high reliability ... good advise: linksys is switching to slower spped too early .. iow it has still good signal but decides to decrease speed .. so disable auto fallback ;0)