How to test DECT NR+ data communication and communication rate between two nrf9151 development boards

[chen.hao]

I have two NRF9151-DK boards in my hand. I want to realize DECT NR+ data communication between the two boards and test their communication rate. What should I do?

[Simonr]

Hi

Please check out the DECT NR+ samples available in the nRF Connect SDK here: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/dect/dect_phy/dect_shell/README.html 

If you're new to the nRF Connect SDK as a whole, I recommend starting out with the Nordic DevAcademy and the nRF Connect SDK fundamentals course as well as our Cellular IoT fundamentals course available here.

Best regards,

Simon

[chen.hao]

Hi Simonr，

Below is my test log：

desh:~$ > dect perf -c --c_gap_subslots 3 --c_tx_mcs 4 --c_slots 4 --s_tx_id 39 -t 10 --channel 1658
dect perf -c --c_gap_subslots 3 --c_tx_mcs 4 --c_slots 4 --s_tx_id 39 -t
10 --channel 1658
dect phy api initialized for perf command.
Starting perf client on channel 1658: byte count per TX: 700, slots 4, gap 43200 mdm ticks, mcs 4, duration 10 secs, expected RSSI level on RX 0.
perf command started.
perf tx operation completed:
total amount of data sent: 3062500 bytes
packet count: 4375
elapsed time: 10.00 seconds
data rates: 2450.00 kbits/seconds
Requested results from the server...
RESULT_REQ sent.
Server results received:
perf server rx operation from tx id 38:
total amount of data: 3062500 bytes
packet count: 4375
elapsed time: 10.02 secs
data rates: 2444.13 kbits/secs
rx restarted count: 0
PCC CRC errors: 0
PDC CRC errors: 0
out of seqs: 0
PCC RX: MCS: 4
PCC RX: RSSI: min: -36, max: -32dBm
PCC RX: TX pwr: min -12, max -8 dBm
PCC RX: SNR: min: 92, max: 112

RX for perf results done.
perf command done.

I used two nrf9151-dk boards to test the dect perf command, and the measured speed was 2444.13 kbits/secs. Is this speed normal?

Thanks

[Susheel Nuguru]

Hi chenhoo,

The data rate you've measured aligns with the current performance capabilities of the nRF9151-DK when utilizing DECT NR+ technology. While the theoretical maximum data rate for DECT NR+ can reach up to 3.4 Mbps under optimal conditions, but based on this thread, it looks like there is a limitation on current implementation for scheduling packets back to back. I am not sure when this current limitation is scheduled to be fixed.

[jszhang]

Hi susheel nuguru,

NRF9151 has an external PA chip. When using the dect function, may I ask what needs to be configured in the dect_shell routine to make the PA work properly?