• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 56 subscribers
  • Views 2961 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CC2530: Low LQI value for a zigbee router node

Ashwin Natarajan
Intellectual 405 points

Part Number: CC2530
Other Parts Discussed in Thread: Z-STACK

Hi,
We have a network with one coordinator (concentrator) and 80 nodes. The average LQI of the nodes in the network is about 60. But there is one particular node that has a low LQI (an average of 20). All the nodes that are close to it have LQI's of 60 or so, but the LQI of this particular node keep swinging between 5 and 20. Is there any cause and solution for this?

Thanks,

Ashwin N

  • 0
    Guru 735695 points
    I sounds like HW issue. I suggest you to do RF test on this specific board first.
  • 0 in reply to YiKai Chen
    Intellectual 405 points

    The device works sporadically. Doesn't this mean that the device is not using intermediate nodes effectively to route its packets to the coordinator?

  • 0 in reply to Ashwin Natarajan
    Guru 735695 points
    I couldn't understand your descriptions and question. Can you elaborate?
  • 0 in reply to YiKai Chen
    Intellectual 405 points
    I apologise for the confusion.
    My main question on this forum thread is why a certain device (router) has low LQI. The other router devices that are installed near this problematic device have good LQI (60-70) whereas this particular problem device has low LQI (5-20).

    Is this (problematic) device not routing its packets using the intermediate nodes in the network (Maybe this is the reason for this low LQI)? Is this node directly communicating with the concentrator instead of passing the message through the mesh network?

    Is there any way we can see the hop count and even the hops that a node uses when sending packets to the coordinator?
  • 0 in reply to Ashwin Natarajan
    TI__Guru**** 220487 points
    Hi Ashwin,

    The Z-Stack route discovery mechanism searches all possible routes between the source and destination devices and tries to select the best possible route, while route selection is performed by automatically choosing the route with the least possible link cost to all neighbors. As YK mentions this could be due to HW, or possibly distance between nodes depending on your network topology. You can use NLME_RouteDiscoveryRequest to issue route discovery, and process the route reply along with your routing table entries.

    Regards,
    Ryan