Issue link: https://resources.mouser.com/i/1520713
Beyond the Wires 14 ST at CES 2024 — Bluetooth LE Auracast ™ Broadcast Audio Use Cases These elements work together to change lives. Starting at a personal level, LE Audio can enable hearing aids whose sophisticated electronics can be packaged outside the earbuds. Bidirectional CIS links and the LC3 codec would allow low-latency, synchronized connections between in-ear microphones, sophisticated external signal processing, and earbuds. And the ability to handle multiple channels means users can—finally—actually hear telephone conversations, broadcast public-address announcements, and the TV at the local bar through additional CIS and BIS links to the earbuds. The case is similar for wireless stereo. In Bluetooth Classic, audio is daisy-chained from handset to earbud to earbud, requiring an additional radio and antenna in the relaying earbud, and hence additional power consumption. Then, getting the two earbuds synchronized requires proprietary algorithms that limit interoperability. With LE Audio, the handset can connect isochronously to each earbud in parallel, and users get the sound quality of LC3, with the CIS connections synchronized in time. BIS opens up many more possibilities. An earbud user can share her music without having to lend an earbud. Nearby friends can simply opt-in to her broadcast directly with their handsets. In those impossible-to-hear places like gyms or sports bars with a dozen TV screens, users can select a broadcast stream from a particular screen and actually enjoy it—no muted TVs, no battle of the little TV speakers. At concerts, attendees can receive a broadcast directly from the mixing board and actually hear the music at near-studio quality; perhaps they can select from among different mixes. Videos or live events with multiple-language broadcasts create other opportunities. The user can select the language in which to listen. What It Takes Implementation of these features is not trivial. The LC3 codec, required for LE Audio to ensure interoperability, may require less memory than an SBC codec. But it may also require careful coding and more processing performance. The functions that make multiple broadcasts or connected streams possible—Isochronous Channels (ISOC) and Enhanced Attribute Protocol (EATT)—are options to Bluetooth LE. They reside in the controller link layer and in the host stack, respectively. Extended advertising, which is required to establish BIS channels, also adds to the controller workload. Altogether, the needs of codecs, host and controller tasks, the audio framework, top-level profiles, and applications will dictate high CPU performance in a SoC, but at low power. Device design for Bluetooth LE Audio and Auracast will need special attention when choosing the right wireless microcontroller. The design needs hardware that can handle all the necessary functions of the target product while meeting requirements such as performance, power, latency, memory, cost, time-to-market, driver/middleware/library support, and longevity. But that effort will open whole new audio experiences for users.