NWA1123ACv3 Energy bursts accross 2.4GHz channel 1 and 11

ASGR

Hello Support,

Please can you tell me if this is normal behaviour?

The image shows a scan from the 2.400GHz to 2.433GHz, channel 1, taken from my TinySA Ultra+. I've isolated it to the wireless router and bursts change as I change channels. I get the same high energy bursts on channel 11. It is not continuous but changes through out the day. Usually, I observe a consistent diagonal dot pattern.

When I switch the router off, the burst disappear. What is more interesting is that when I leave it turned-on, connected to the switch, but disconnected from the firewall, the bursts also stop as if externally triggered.

I tried installing the latest firmware but the high energy bursts continue? Please advise…

Current set-up: Netgate 1100 → Zyxel GS1900-10HP → NWA1123ACv3

Output from Tiny SA Ultra+ 2.400GHz to 2.433GHz (1) and 2.441GHz to 2.483GHz (11):

SOURCES:

https://en.wikipedia.org/wiki/List_of_WLAN_channels

Zyxel_Melen

Hi @ASGR,

Before we check this issue, may I know some details first?

1. What makes you want to check it with the Tiny SA Ultra+? Is there any issue trigger you to check?
2. "I've isolated it to the wireless router and bursts change as I change channels" What do you mean change channels? The Wi-Fi radio channel? Or?

Thanks for sharing the information.

ASGR

Hello Melen,

I bought the TinySA to monitor other external factors in the 2.4GHz to 2.5GHz frequency range unrelated to the wireless router and then by chance I noticed these intermittent high energy burst. They are not consistent but somewhat random.

Initially, I assumed that the bursts were external to my environment but noticed that the bursts power levels were generally the same power level as the observed normal wireless router transmissions. I took readings from different locations (distanced/obstructions) and the power levels were generally aligned.

I use my Gigahertz Solutions HF-32D to scan my environment so I am aware of all the devices that eminate any supported radio frequencies and turned them off one by one to find the culprit. Through a process of elimination I identified the wireless router as the source. However, I will continue to collect data to confirm.

Yes, the radio channel. I see high energy bursts on channel 1 and 11 as I change configuration for the 2.4GHz radio.

Zyxel_Melen

Hi @ASGR,

Thanks for your feedback. So, change any configuration for 2.4GHz radio, at channel 1 or 11, will cause this burst. I think this is a hint for us, I will check with our engineer and keep you posted.

ASGR

Yes. I've disconnected the cables from my firewall, alternating WAN and LAN ports (wireless router still connected to switch), and the bursts seem to stop. When I plug the cables back in after a while the burst restart.

Zyxel_Melen

Hi @ASGR,

Could you also share an image that is under normal status? This can help us compare the difference. Thank you~

ASGR

Hello,

This is for the frequency range 2.400GHz to 2.433GHz / channel 1 only (as per wikipedia.org)

Zyxel_Melen

Hi @ASGR,

Sorry for the delayed reply since we were waiting for the shielding roam to test.

NWA1123ACv3 Frequency change between 1 and 11.mp4

In our testing, we didn't see any similar issue to what you encountered. So, we assume this issue might not due to our AP. Could you help to clarify if your AP is working properly? Can you connect its SSID/Wi-Fi and have traffic?

ASGR

Hello Melen,

Sorry for late reply. Yes traffic is coming through.

I tested the wireless router with a ROKU 3930X in the same room and got the following spectrum:

Then I took the ROKU device to another room (about 8 meters away) and got this spectrum.

I'm still seeing energy bursts but at a much lower level. I believe these bursts are data being transmitted to the device from the wireless router. For comparison, I connected my phone to the same network and played some x.com video posts and saw the same energy bursts as in the first photo.

Would this be a normal profile for the wireless router to transmit data to devices?

I do have the Output Power set to the max of 30.

Zyxel_Melen

Hi @ASGR,

After discussion with our engineer, we think this is a normal behavior since the signal you found is more likely the LTE signal. Because your test environment is not shielding roam, which is possible to have other siganl like radio, LTE, and etc. As I mentioned, our test was tesing in a shielding roam, therefore, this behavior is propabile not an issue.

ASGR

Thanks Melen, the energy burst were present as I changed channels, i.e. first noticed when channel 11 was used for the wireless network and then again when I changed to channel 1. Would the channel number be irrelevant?