RF range performance difference between the IEEE 802.15.4 PHY test tool app and Radio test (short-range)

[Bhavya Mathukiya]

Dear Nordic Team,

Test_1:

I am trying to use IEEE 802.15.4 PHY test tool  app to test the RF performance of the custom nrf54l15 module and nrf54l15dk kit.

Setup:

CMD: nrf54l15 custom module

DUT: nrf54l15dk

Distance between the two boards: 30cm

I am performing a ping test to count PER based on ACK / NO ACK using a Python script.

I am basically sending below commands to the CMD device

custom changemode 1
custom setchannel 0 0 8 0 # 1 << channel 11, big-endian octets
custom rsetpower 0 0 0
custom lsetpower 0 0 0
custom lgetrssi

# repeatedly send 100 pings, count ACK vs NO ACK to calculate PER

custom rping

I am sometimes getting even below 5% PER at this short distance. Tested this for 11, 20, 26 channels

Test_2: RF performance testing using Radio test (short-range) app.

Using a Python script, set the commands below on both boards.

data_rate ieee802154_250Kbit
start_channel <5|50|80> # 802.15.4 ch 11 / 20 / 26 = 2405 / 2450 / 2480 MHz
end_channel <same>
output_power pos0dBm

receiver: start_rx 500
transmitter: start_tx_modulated_carrier 500

In this app, PER is calculated in-built. It is observed at the same distance and with the same board, PER is in the range of 0 to 2% around.

Can you please let me know what could be the reason of this difference in RF performance between these two apps?

Best regards,

Bhavya

[Ressa]

Hi,

You are testing two different things. In radio test, the transmission is one-way without any ACK exchange, while the PHY test tool command "rping" is a two way communication means after transmission it waits for ACK. So basically there is higher probability of error in latter. Also other than that, the frame/packet length is longer for testing with  IEEE 802.15.4 PHY test tool as it is a full MAC-layer data exchange. For radio test , the packets are shorter as it a raw PHY test which is more relevant for evaluating sensitivity level. For longer data stream the probability of error is higher. So considering all the conditions, it makes sense to have lower PER with radio test. 

IEEE 802.15.4 PHY test tool — nRF Connect SDK 3.4.0 documentation


Br,
Ressa