Chief Delphi - WiFi at a week zero event

Chief Delphi (http://www.chiefdelphi.com/forums/index.php)

- Off-Season Events (http://www.chiefdelphi.com/forums/forumdisplay.php?f=20)

- - WiFi at a week zero event (http://www.chiefdelphi.com/forums/showthread.php?t=133862)

Re: WiFi at a week zero event

Quote:

Originally Posted by Tanis (Post 1437341)

Since week zero events will be using last year's FMS (or a third party FMS such as Cheesy Arena), you will need to go into the RoboRIO's settings and set it to a static IP of 10.xx.yy.2, and make sure the radio isn't trying to serve out IPs via DHCP.

It's probably easier to make sure your Router/AP is serving out addresses via DHCP on a 10. that won't conflict with a team, 10.0.101.XX should be fine, with a subnet mask of 255.0.0.0. Then the DSes with their static IPs can happily talk to the roboRIO with its DHCP address.

Re: WiFi at a week zero event

Quote:

Originally Posted by RufflesRidge (Post 1437603)

Not true. If the WiFi channels are saturated, it doesn't matter what your IP/subnet you are. You are competing with data trying to use the same pipe (channel) to go somewhere else.

What you are saying is true if you had hard wire and a switch. The switch can isolate sub-nets to maximize data throughput within the sub-net.

WiFi is like a shared wire. Nothing you can do if the wire is saturated.

Re: WiFi at a week zero event

The DHCP address range can be an issue ONLY if you are planning to use the same SSID as used by FMS and the robots. Clearly, you should not be doing that, even if you could. So, IP addresses are not an issue.

The issue is whether you are using the same RF channels that are being used by FMS. FMS typically uses low numbered channels in the 5 GHz band. If someone else was also using this particular channel, then the bandwidth available for robots could be reduced. FMS typically uses one channel, but may use multiple bonded channels (I heard). Depends on the FTA.

So, using the 2.4 GHz band WILL not cause problems for robots if you use FCC approved AP devices. FCC testing verifies that the device will not transmit radio energy in other ranges. The image posted by jvdiv shows the 2.4 GHz band (Channels 1 - 14). Please scan the 5 GHz range as well, I am sure your school uses channels in this range as well. This info will be useful to the FTA.

Using 5 GHz (Channels > 14) SHOULD not cause problems either as long as you don't use the channel(s) used by FMS. These channels do not overlap like the 2.4 GHz channels.

If there is a problem, find the real cause. Don't be a Luddite. There is a lot of unjustified FUD in this area and a lot of people repeat incorrect info that they hear from other uninformed people. Unfortunately, this serves to distract focus from the real problems and delays a good solution. :mad:

Re: WiFi at a week zero event

Quote:

Originally Posted by solopilot (Post 1437653)

The DHCP address range can be an issue ONLY if you are planning to use the same SSID as used by FMS and the robots. Clearly, you should not be doing that, even if you could. So, IP addresses are not an issue.

The issue is whether you are using the same RF channels that are being used by FMS. FMS typically uses low numbered channels in the 5 GHz band. If someone else was also using this band, then the bandwidth available for robots could be reduced. FMS typically uses one channel, but may use multiple bonded channels. Depends on the FTA.

So, using the 2.4 GHz band WILL not cause problems for robots if you use FCC approved AP devices. FCC testing verifies that the device will not transmit radio energy in other ranges. The image posted by jvdiv shows the 2.4 GHz band (Channels 1 - 14). Please scan the 5 GHz range as well, I am sure your school uses channels in this range as well. This info will be useful to the FTA.

Using 5 GHz (Channels > 14) SHOULD not cause problems either as long as you don't use the channel(s) used by FMS. These channels do not overlap like the 2.4 GHz channels.

If there is a problem, find the real cause. Don't be a Luddite. There is a lot of unjustified FUD in this area and a lot of people repeat incorrect info that they hear from other uninformed people. Unfortunately, this serves to distract focus from the real problems and delays a good solution. :mad:

This is a week-0 event, without official FRC hardware and no FTA. Depending on their specific setup, they may indeed be using the 2.4 ghz range. Providing General advise is good, getting super specific without knowing the local setup is not.

Re: WiFi at a week zero event

Quote:

Originally Posted by Jon Stratis (Post 1437656)

Sorry, I came back to edit my post and found your speedy response. Since the field would be using 2.4 GHz, my update is to agree that it would be wise to clear one of the 3 channels and dedicate it to FMS.