Subject: Scheduling Conflict During Beacon Scan and Association Between DECT NR+ Nodes (Sink–Relay–Leaf Topology)

[Muhammad Ahsan]

Description:

Hello, We are developing a DECT NR+ communication setup using multiple nRF9161 DK boards arranged in a Sink–Relay–Leaf topology.

Each board operates as a DECT node (sink, relay, or leaf) and participates in a bidirectional communication chain. In this setup:

• Relay nodes must associate both upstream (with the previous node) and downstream (with the next node).
• All boards begin by starting a beacon, scanning for neighboring beacons, and then initiating association with detected neighboring nodes.

Observed Problem:

When the relay nodes start beaconing followed by beacon scanning and then association, the association step fails with scheduling conflict errors.

Specifically:

• After all nodes start their beacons and begin scanning, each node detects the neighboring beacons correctly.
• However, when the association procedure starts between nodes, associations fails with an error related to “scheduling conflict”.
• This happens most often on relay nodes, which attempt to associate with two neighbors (both uplink and downlink).

Codes:

NRF_MODEM_DECT_PHY_ERR_OP_SCHEDULING_CONFLICT = 0x1004

Regards,

[ErMaqsood]

Hello,

Greeting for the day. 

I appreciate your support.

I currently have a DECT NR+ setup running on the nRF9151, based on the HELLO DECT PHY sample using nRF Connect SDK v3.3.0preview2. I am seeking your guidance on how to route data across a small NR+ cluster, specifically in the following topology:

[cluster1] Leaf (Node1) ⇄ Router (Relay) ⇄ Leaf (Node2) [cluster2]

Could you please advise on the correct approach, configuration, or APIs required to enable multi‑hop data routing between Leaf nodes through the Router?

Thank you.

[Kenneth]

Hello,

Please make a new case for this request.

Kenneth