Auto-Learning via RSSI Using NCK2982 in TPMS ECU Development

[HarunCSaykal]

Hello, I am currently working on a TPMS project and I am close to completing the ECU firmware. I am using the NCK2982 as the RF receiver. There are a few issues I’m currently stuck on, and I would greatly appreciate your support: I would like to implement auto-learning in the TPMS ECU. I am trying to use RSSI-based auto-learning. Is this a valid approach? I can successfully receive data from multiple sensors and transmit it over CAN. I am also able to read the RSSI values. However, I am unsure how to determine which sensor a specific RSSI value belongs to. I noticed that the payload containing the RSSI does not include the sensor ID. Am I doing something wrong? If this behavior is expected, what is the correct way to identify which sensor the RSSI value corresponds to? Thank you very much in advance for your support.

[KaiLi]

Hello @HarunCSaykal 

If all your sensors communicate via CAN, then you CAN distinguish which CAN device the information comes from through the CAN ID. However, the NCK2982 should communicate via the NFC interface, so I'm not quite sure what your application scenario is like. Could you share your schematic?

[HarunCSaykal]

Hello,

The concept is as shown in the attachment: an ECU receives data from multiple sensors.
I am successfully receiving the sensor data, and the payload includes the Sensor ID. However, I am unable to determine which sensor the RSSI value corresponds to.

I have also attached the results of my work using the CDK tool. In that setup, I am receiving data from two sensors. The payloads contain the Sensor IDs, but again, I cannot identify which sensor the displayed RSSI value belongs to.

How can I determine which sensor a given RSSI value is associated with?

Thank you for your support.

Best regards,

[KaiLi]

Hello @HarunCSaykal 

Is NCK2982 in the ECU or in the sensor?
From the application scenario you provided, each sensor should communicate with the ECU through the NFC interface, right? From the log you provided, the ID and RSSI are one-to-one corresponding, but you can't physically distinguish different IDs, right? To be honest, it's difficult for us to help you with this. Can you read them one by one? This way, the ID number can be matched with the physical object.

[HarunCSaykal]

Dear KaiLi,

Apologies for the late reply.

I am using the NCK2982 in the ECU, and the communication is via RF.
In the logs, there are two sensors, and I am successfully receiving data from both. I can also successfully read the RSSI values.

However, what I don't understand is: how do I determine which sensor the received RSSI value belongs to?

I am also reading the packets over SPI. The packet in which I read the RSSI value does not contain any ID information.
This is exactly the point where I am stuck. How can I associate the RSSI value with the corresponding Sensor ID?

I would really appreciate your guidance on this matter.

Best regards,

[KaiLi]

Hello @HarunCSaykal 

I believe that different sensors can be distinguished by ID. The problem you are facing can only be tested one by one. Since the sensor and NCK communicate through the NFC interface, the communication distance between them should be about 10cm. So you can move one of the sensors to a longer distance. In this way, only one sensor should be within the effective communication distance. In this case, NCK can only read the RSSI of one sensor, so that the ID can be matched with the RSSI. By this way, another sensor can be distinguished.

[HarunCSaykal]

Hello,

I am currently receiving support through the dedicated portal. I believe the issue will be resolved there.
Thank you very much for your help and support.

Best regards,