Capture and Security Challenges Relating to the LE Isochronous Physical Channel: The Benefits of tZERO Tracking Technology

Summary

Explains why capturing Bluetooth LE broadcast audio requires more than observing advertising packets, and promotes a proprietary capture method.

Key findings

• Page 2 distinguishes broadcast isochronous streams (BIS), established using advertising packets, from connected streams. BIS receivers send no acknowledgements; the broadcast uses unconditional retransmissions.
• Page 2 describes LC3 Auto-Detect as an Ellisys feature for detecting and decoding LC3 traffic even without capturing its configuration parameters.
• Page 6 explains that an analyser must collect broadcast-group parameters from periodic advertising to capture BIS traffic. Software processing can miss initial packets while configuring capture; Ellisys claims its tZERO method tracks active BIS streams in real time without blind periods.
• Pages 4-6 describe additional requirements for capturing encrypted traffic. The note does not present an independently measured capture-success rate, radio-level calibration uncertainty or receiver audio-quality test.

Limits

A September 2021 maker note about the LE Audio transport underlying Auracast, rather than a venue commissioning standard. Its claims of uninterrupted capture promote its own technology; there is no comparative capture-error dataset. Applies here to the shared broadcast transport, not a hearing-device listening trial.

Read the original

www.ellisys.com/technology/een_bt10.pdf

Link checked 13 October 2026. We link to the original and do not host copies.

Cited in

• Which meters and apps measure loops and Auracast, and how accurate are they?Partly answered

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