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New Member
Posts: 15
Registered: ‎10-04-2009
Kudos: 2

Bullet M Low Power Mode?

I am using Bullet M2's for a 12 mile link. This hop uses 2 Bullet M's back to back with one as a Station, and the other as an AP. This hop is being powered by a solar panel and batteries. I have sufficient power budget to power one Bullet continuously without a problem.

I would like to know if there is a way to put the Bullets into a low power mode. In order to allow the link to run on the available solar power and battery capacity, I need to be able to reduce the power consumption of at least one of the Bullets manually or on a schedule. Has anyone had experience with what is possible here?

I have worked with some other embedded processors that allow the processor to sleep or reduce the CPU speed when it is not needed. Can the real time clock of the Bullets run without the main CPU running and trigger an interrupt to wake up the main CPU?
What I would like to do is to have the Bullets sleep from say 1am to 6am to conserve power. If it isn't possible to suspend the CPU, can I run a process that will underclock it at certain times? I see that DD-WRT firmware allows over/underclocking of some chipsets.

Similarly, can I disable the WLAN chipset during certain times? I am assuming that at least this is possible because it is an option in the AirOs web configuration(Does this actually turn off the radio chipset?). I haven't checked the power draw difference, but from experience with other embedded systems, the WiFi receiver itself draws a considerable amount of continuous current. I would expect the CPU idle current to be fairly low. I measured the average current draw of the Bullet to be approximately 250mA@12V with no activity. This was measured with a standard DMM and I understand it doesn't account for current spikes due to transmit beacons etc... The current jumps to about 330mA with something such as a request on the configuration page over ethernet.

Can someone help me out with a script/cron job to at least disable the radio on a schedule, as I'm not very familiar with linux or the command to disable the radio.

Although these are mainly used as CPE's it would be nice to see this as a feature in a future firmware release.
Previous Employee
Posts: 9,171
Registered: ‎08-17-2007
Kudos: 24

Re: Bullet M Low Power Mode?

I am using Bullet M2's for a 12 mile link. This hop uses 2 Bullet M's back to back with one as a Station, and the other as an AP. This hop is being powered by a solar panel and batteries. I have sufficient power budget to power one Bullet continuously without a problem.

I would like to know if there is a way to put the Bullets into a low power mode. In order to allow the link to run on the available solar power and battery capacity, I need to be able to reduce the power consumption of at least one of the Bullets manually or on a schedule. Has anyone had experience with what is possible here?

I have worked with some other embedded processors that allow the processor to sleep or reduce the CPU speed when it is not needed. Can the real time clock of the Bullets run without the main CPU running and trigger an interrupt to wake up the main CPU?
What I would like to do is to have the Bullets sleep from say 1am to 6am to conserve power. If it isn't possible to suspend the CPU, can I run a process that will underclock it at certain times? I see that DD-WRT firmware allows over/underclocking of some chipsets.

Similarly, can I disable the WLAN chipset during certain times? I am assuming that at least this is possible because it is an option in the AirOs web configuration(Does this actually turn off the radio chipset?). I haven't checked the power draw difference, but from experience with other embedded systems, the WiFi receiver itself draws a considerable amount of continuous current. I would expect the CPU idle current to be fairly low. I measured the average current draw of the Bullet to be approximately 250mA@12V with no activity. This was measured with a standard DMM and I understand it doesn't account for current spikes due to transmit beacons etc... The current jumps to about 330mA with something such as a request on the configuration page over ethernet.

Can someone help me out with a script/cron job to at least disable the radio on a schedule, as I'm not very familiar with linux or the command to disable the radio.

Although these are mainly used as CPE's it would be nice to see this as a feature in a future firmware release.


Hello,
We currently have all power save modes disabled, as they are very buggy from Atheros. This is something we will look into in the future as our software matures for these products.
Thanks,
Mike
New Member
Posts: 15
Registered: ‎10-04-2009
Kudos: 2

Re: Bullet M Low Power Mode?

Hi Mike,

Thanks for the reply. I will look forward to seeing some power management features in the future.

Is there any info that you can give me such as how to enable/disable the Wireless interface from either telnet or SSH? I haven't seen anything on the forum or Wiki about telnet or SSH commands . Where can I find this info?

At the very least I'd like to script this change to run from my PC on a schedule. Since I may just want to disable one Bullet, I can leave the ethernet side on to reactivate it remotely.

Does this actually turn off the wireless radio?

Thanks,
James