how to aviod the signal interference issue between WIFI and Zigbee？

The Seven

Guru 11440 points

Other Parts Discussed in Thread: Z-STACK, CC2530

Hi ALL

there is a PCBA，which supply the WIFI 2.4G signal and there is alway a zigbee coordinator running.

I found that sometimes the ZC boardcast msg alwas being resend as more as 3 times in NWK,

although its ZCL transmit sequence number is same，

and ZED response msg alway need to resend so many times then it could receive the ACK

Q1：

In order to aviod the signal interference issue ， could we change the coordinator channel while it is running？

When 2.4G wifi choose the channel 1, change the coordinator channel far from the WIFI channel ， such as 25channel ！

Q2 :

If above method is OK to implement, How about WIFI bandwidth change as 40Mhz?

because so many people set the WIFI bandwidth as 40MHz， is that work change the ZC channel far from the WIFI channel to avoid

the signal interference issue？

BR!

over 9 years ago

0 YiKai Chen over 9 years ago

Guru 735645 points

It's not OK to change channel while ZC is running.

0 The Seven over 9 years ago in reply to YiKai Chen

Guru 11440 points

when ZC running， the channel and PANID could not be change any more？

0 YiKai Chen over 9 years ago in reply to The Seven

Guru 735645 points

Channel can be changed if there is interference and frequency agility is enable. However, this is done by Z-Stack not application. You can refer to chapter 11. Network Manager in Z-Stack Developer's Guide.pdf.

0 yun ye85 over 8 years ago in reply to YiKai Chen

Intellectual 325 points

I had a bad demo a few days ago, that the ZigBee mesh network communication was totally jammed by WiFi booster.

Looks at Philips Hue APP, it allows end-user to change ZigBee channels. So I still don't understand why TI Z-Stack can not allow user to change Channel in run-time after ZC formed a network.

I tried to use ZMacSetReq(ZMacChannel, &newchannel), and osal_nv_item_write(ZCD,NV_CHANLIST,...). Both functions can not change ZC channel.

Can anyone explain how TI Z-Stack set the channel? Why can not be changed in run-time?

Is there any way to change the channel (for end-user), even we have to let all devices re-joining? It is a very important feature in-field.

Thanks.

0 YiKai Chen over 8 years ago in reply to yun ye85

Guru 735645 points

You definitely can change channel at run time but I would still say it's dangerous. You can refer to section 11.2 Channel Interference in Z-Stack Developer's Guide.pdf.

0 yun ye85 over 8 years ago in reply to YiKai Chen

Intellectual 325 points

Thanks YK. Section 11.2 seems quite complex, and hard to verify also.
Any simple way to change the channel? For example, user already knows which channel is noisy, so before setup the network, user can choose a known cleaner channel for ZC to setup the network.

0 YiKai Chen over 8 years ago in reply to yun ye85

Guru 735645 points

Z-Stack 3.0 implements channel selection on its examples so you can have a look at it.

0 Alessandro Soncini over 8 years ago in reply to YiKai Chen

Intellectual 675 points

If you want to change the channel, you can use the code bellow.

#define MIN_CHANNEL 11 // 2405 MHz
#define CHANNEL_SPACING 5 // 5 MHz

//channel variable must be a value between 0 and 15.
void set_rf_channel(uint8 channel)
{

FREQCTRL = (MIN_CHANNEL + channel * CHANNEL_SPACING); //Calculates the channel frequency according to IEEE directive.

}

I'm not familiar with ZSTACK but I believe you should be aware that it can change the channel again by its own without notice.

0 The Seven over 8 years ago in reply to yun ye85

Guru 11440 points

why do you want to change the channel in the running time ？

0 yun ye85 over 8 years ago in reply to The Seven

Intellectual 325 points

Thanks for your reply. As mentioned, if the environment noisy is too high for the pre-selected channel, then end-user can change the ZC channel on-site. Reference is Philips Hue Hub.

0 yun ye85 over 8 years ago in reply to YiKai Chen

Intellectual 325 points

Thanks YK. It's an important information, need to move to Z-Stack 3.0.

0 yun ye85 over 8 years ago in reply to Alessandro Soncini

Intellectual 325 points

I guess this won't work in Z-Stack. Thanks anyway.

0 YiKai Chen over 8 years ago in reply to yun ye85

Guru 735645 points

If you don't want to use Z-Stack 3.0, you can refer to the example and porting it to old Z-Stack. However, TI always recommend developers to use latest Z-Stack.

0 Alessandro Soncini over 8 years ago in reply to yun ye85

Intellectual 675 points

Hello Yun Ye85.

I don't see why it will not work.

By using the register FREQCTRL you are setting the channel directly into the hardware. This register name is used on CC2530. If you are using other IC, maybe you will need to look if it uses the same register name.

By using that code, you are bypassing the hardware abstraction layer and setting the channel information by yourself.

Be aware that channel 0 corresponds the IEEE channel 11, as well as channel 15 corresponds to IEEE channel 26.

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how to aviod the signal interference issue between WIFI and Zigbee？