XIAO nRF54L15 / nRF52840: Coded PHY Extends Communication Range by 4x — at the Cost of Current Consumption

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I measured how much the communication range improves when using Coded PHY with XIAO nRF54L15 and XIAO nRF52840.
Compared to 1M PHY, using 8S Coded PHY increased the communication range by more than 4x, which closely matches the theoretical expectation. However, this improvement comes at a cost: due to the increased amount of transmitted data, the current consumption with Coded PHY more than 2x.

For both nRF54L and nRF52, measurements were performed under the following conditions:

  1. Transmit power: 8 dBm for both Peripheral and Central (1M PHY and 8S Coded PHY)
  2. Bidirectional communication every 1 second using 16-byte data via Notify and Write
  3. Using onboard ceramic antenna
  4. Devices placed 1 m above ground on a damp baseball field
  5. Communication range measured at the point where the connection was lost

RSSI values varied significantly and should be considered only as a reference.
In practice, connections were lost when RSSI dropped below approximately −90 dBm for 1M PHY and −100 dBm for Coded PHY.

It should also be noted that the onboard ceramic antenna is directional. Maintaining optimal antenna alignment between the Peripheral and Central devices while measuring long communication distances was therefore quite challenging.

While acknowledging that the results depend on measurement conditions, the following conclusions were obtained:

  1. For both nRF54L and nRF52, the communication range with Coded PHY was more than 4x that of 1M PHY.
  2. The communication range of nRF54L was more than 2x that of nRF52.
  3. The maximum measured communication range for nRF54L was 132 m.

Regarding current or charge consumption on nRF54L, compared to 1M PHY:
4. The 1-second average current with Coded PHY was more than 2x that of 1M PHY.
5. The charge consumed during the TX period was approximately 6x higher.
6. The charge consumed during the RX period was approximately 5x higher.

I hope these results are useful for others evaluating Coded PHY.

POST_nRF54L_CodedPHY.zip (1.1 MB)

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1 Like
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wow thanks for the research… life is about trade-offs!

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Hi there,

Solid as per usual, I had found the Ceramics worked best for a setup with ends pointing at each other :+1: As well as a 2x improvement indoors with range over the nRF52 Series from 30m-40 to easily 90m+ :grin: the External antenna works but also adds to the power drain on the overall system. However more testing is needed :crossed_fingers:

GL :slight_smile: PJ :v:

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We made a test with our boards (Arduino Nano BLE 33 on one side and Seeed Xiao nRF52840 on the other side) in a big empty turkey house with simplex measurement transmission on BLE beacons of 31 byte payload every 20 milliseconds. A distance of 75 meters was possible (1 Mbit PHY, 8dB).

That was with the prototypes of a universal measurement system. If it is not too complicated we will use nRF54L15 instead of nRF52840 in the future. With the hope, to have more reserve and flexibility.

Thank you for your investigations.

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Since I don’t have an external antenna, I conducted experiments using the onboard ceramic antennas for both the nRF54L and nRF52. I mounted them on a camera tripod and adjusted the orientation of the peripheral and central devices so their antenna directional patterns faced each other. However, this became difficult and troublesome as the distance increased. The nRF54L antenna seems to have higher gain due to its larger size, allowing it to achieve greater distances than the nRF52.
If anyone can perform similar experiments using an external antenna, I’d be interested in the results.