[ipwave] example of problematic PHY setup
Alexandre Petrescu <alexandre.petrescu@gmail.com> Fri, 12 April 2019 13:30 UTC
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From: Alexandre Petrescu <alexandre.petrescu@gmail.com>
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Subject: [ipwave] example of problematic PHY setup
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In my explanations I often say that PHY and MAC must be setup properly in order for IP to work on them. It's good to use the right channels, to understand the propagation models, etc. Here is one example of problematic PHY deployment from the world of lidars (it's a PHY, but it's not message exchange nature; it's more bouncing signal nature). This recent deployment of lidar on pole is probably targetting sharing its data with cars on 5G. The lidar is apparently a Quanergy M8 model. I strongly suppose it does not see right under it. It may work on a distance, but not immediately below it. It is a problem. It is the same kind of problematic issues that are also done with many OCB IP-RSU deployments: their PHY covers in places they should not (e.g. outside the road) and their coverage on the road is lesser. These kinds of problems of PHY deployment lead to wrong things happening at PHY, at MAC and implicitely at IP layer. But it is not because of IP, nor because of ND. One cant fix these problems by improving ND. Maybe a little ND timer tweaking could help something, but much less than what an angled lidar, or focused MIMO OCB antennas could solve. Alex
- [ipwave] example of problematic PHY setup Alexandre Petrescu