GCDC forum

I have studied IEEE 1609 (especially 1609.4 on multichannel operations) and am a bit puzzled about the channel switching. From my research I find that good beaconing in a realistic highway scenario may already reach the limit of a single channel's capacity, and then the idea is for the receiver to reside on a different channel part of the time...

Matters would change, of course, if we were to use two seperate receivers (with all the appropriate shielding/filtering etc.). I have also been in contact with some people working on broadband receivers and they proposed a very elegant solution: just receive all seven WAVE channels at the same time. But there is no 802.11 hardware which can do this at the moment, so it is purely hypothetical.

As for which messages on what channel, I would definitely put alpha on one channel, and platooncontrol stuff may be moved to another to increase capacity on the 'beaconing channel'. But that's just a quick guess.

greets,
Team FUTURUM

Hi Martijn,

I agree with your considerations; we are quite concerned -in general- about the danger of congestion on the 11p channel(s). However, there still seems to be no agreement on which channel to use for what, and how to avoid/mitigate congestion (however, there is now ETSI's Distributed Congestion Control that looks quite promising).

We decided that, to keep things simple and feasible, all GCDC messages will be put on a single 11p channel, 5890 MHz by default. Participants should be prepared to switch channels though (on a one-time basis: We may do the entire GCDC on a different channel; we will not change channels during the event!).

Best,

Jan