Those are very good features and have been around a while now but we still ended up ebaying all of our 900 gear. I think the fact that they still use csma/cd and don't include GPS support w/ every product line is what has stopped them from having that killer product...

Jon Langeler
Michwave Tech.

Tom DeReggi wrote:

I'm going to save my 4.0 Firmware evaluation results for later, after I'm finished testing. But while working with ED Wyatt this past week, (ps. thanks Ed for the time), It reminded of some of the cool features that had existed in the Firmware (supported on V3 also)

One that sticks out is the way that they do Automatic Transmit Power Control. Of course this feature is needed to prevent unnecessary interference including at the Cell Site, by allowing CPE radios to just use the minimum Transmit power required to get a reliable full speed link. Some competitors use ATPC, but it only considers the desired RSSI that is targeted, not necessarilly link quality.

Alvarion's method I felt was engenius. It uses Signal to Noise Ratio as the criteria for adjusting the Transmit Power at CPE. This prevents the Power level from staying lower, if the noise level rises after it is installed. It also was very customizable, with 4 filed values that could be changes to fine tune how you specifically wanted the ATPC to work. (for example, considering entended modulation,), and even had an auotmatic override to gain link association, in case a setting was made that would otherwise prevent good link quality or association. Also in the past, when to much noise was hit heavilly, it would reboot (in case it was an AP lockup), but now it can be set not to reboot if preferred. It now can actually send a trap, to notify you when the reboot would have occured, so you realize that a link is having an interference problem. The end result was, the way they did it, translated to a ATPC feature that would be very advantageous to be used, apposed to a feature that would be disabled.

ATPC may not be a feature that WISPs want, who's desire is to destroy the airways. But its an important feature for encoraging co-existinance, and for that matter, health of your own cellsite's equipment co-location, and commend Alvarion for their accomplishment in that feature.

This feature for other manufacturers may be a factor of which chipsets they use and their ability to measure SNR.

The other thing that was pretty cool, was its famous abilty, to have two seperate memory spaces for Firmware to reside. We were able to have V3 on one image and V4 on the other Image, and with a flick of a switch (command) jump between the firmwares, so that I could test the performance at each of the Firmware versions. This drastically sped up comparative testing time. But what it brings up, is that if you try a new firmware in the field, its not a huge time consuming process to switch back, if you need to see if the old was corrects a newly developed process. When you have a few hundred sites, I could see that being an advantage.

Tom DeReggi
RapidDSL & Wireless, Inc
IntAirNet- Fixed Wireless Broadband

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