Wide area network

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WAN is to get data out (hopefully connect in too). 2009/10 used two GPRS units. Long term aim is for surface network linked to valley internet connection.

This year we will use a WiFi link down from the mountain - we tested high power WiF using antennas from these, they worked fine with usb-wifi and amps - over between Joklasl and Holmur (10km).

Wifi on cafe will need careful power management. Cisco access points are 46V so not good for that end! Should look at lower DC powered unit or even usb at cafe end (with amp?) and

conclusion - make fixed Wifi link Brunhol-ref cafe, use separate WiFi from ice to ref. Backup with GPRS.

need to take care of any cables running at 2.4GHz - LMR240 (8db/30m) is half loss of RG58

WiFi for Base station link WiFi link from cafe to ice is about 1km line of sight. Experiment on 11/6/11 by KM using:

small usb-wifi adaptor -> sma-N adaptor -> WiFi-link Yagi WLY-2450 -> onmiWLO-2450-08 -> N-sma-> EnGenius ECB1220R.

Signal was -68dB at 1.5km ! ie useable. angle of Yagi not too sensitive.

old abandoned ideas/thoughts:

466MHz band dropped - quite slow but OK in the past. Site survey shows these freqs full already: 465.975, 466.475, 466.87, 465.175.

Xbee has limited bandwidth and didn't perform with Yagi base-ref.