CYBT-413034-02 with duplicate-filtering misses packets?

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FrGu_4702376
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First reply posted First question asked Welcome!

Dear Cypress,

We are developing a new version of our product using the CYBT-413034-02. The product is a Bluetooth 'access point' that is scanning for incoming advertisement messages from surrounding peripherals, parsing the payload and then forwarding this to the network.
This system is applied in the 'smart building' industry and we are supplying to international parties such as Microsoft, Ernst&Young, Heineken and Unilever, as well as other large parties in Commercial Real Estate and airports. We are running into some technical issues with our latest product development and hope you can help us in resolving this.

While our device is scanning for incoming BLE advertisements using 'hcitool lescan', we are noticing that packet loss is quite high.
Our peripherals are sending bursts of 0.5s every 30 seconds, and each burst has unique payload. We see in btmon that duplicate-filtering is enabled so we expect one message to come in every 30 seconds, but we are often (>30%) missing these packets. However, when we disable the duplicate-filtering: 'hcitool lescan --duplicates', we reliably receive a burst every 30 seconds, with multiple packets per burst.

It looks like the bluetooth controller is not able to process all incoming messages when 'duplicate-filtering' is enabled. However, from our application we are using higher-level BlueZ mgmt api, which does not allow disabling of duplicate-filtering. Could you help us in understanding and resolving this? Could you explain how the duplicate-filtering is done and if there are any limitations in computing that might cause the 'package-loss' or how we might improve performance?

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