Bluetooth has come a long way since its invention in 1998. Bluetooth has been included in majority of the smart phones, laptops, and feature phones to connect to a wireless headset, earbuds, wireless speaker, and many more devices. Bluetooth’s standard is continuously evolving to support more user applications and lower the power consumption. 

Since the launch of its initial version, Bluetooth 1.0 in 1998, the Bluetooth standard has seen many significant upgrades like Bluetooth 2.0 in 2000, Bluetooth 3.0 in 2009, Bluetooth 4.0 in 2010, Bluetooth 5.0 in 2016, and Bluetooth 5.2 in December 2019. 

Among all the Bluetooth specification upgrades, Bluetooth 5.2 stands out as the groundbreaking upgrade, which is expected to shape the future of wireless audio connectivity for the next 20 years. 

Bluetooth 5.2 specifications provide the details for the implementation of LE Audio, the next-gen wireless connection.

Below are the key features and enhancements of Bluetooth LE 5.2: 

1. LE Audio Broadcast: This is the most exciting feature of LE Audio that enables the same audio source to be connected to multiple audio devices like earbuds and headsets. Using this feature, multiple users can connect to the same audio broadcast and listen to it. It has variety of applications that we will learn about in the LE Audio application section. 
2. Improved Audio Quality: LE Audio has introduced new codec LC3 (Low Complexity Communication Codec) that improves audio quality as compared to previous codecs in the Bluetooth standard. LC3 delivers high quality audio even at lower bit rates, making it ideal for wireless streaming. 
3. Hearing Aid Support: LE Audio includes dedicated features to better support the hearing aids. This makes connecting and listening to the audio stream from devices easier for people with hearing loss. 
4. Low Power Consumption: As discussed earlier, LE Audio has introduced new codec LC3 (Low Complexity Communication Codec), which provides better audio quality over lower bit rates. It means to deliver the same audio quality, Bluetooth 5.2 requires less data to be transmitted, resulting in power saving and improved battery life. Developers can utilize this power saving to either reduce the product form-factor with reduced battery size or increase the battery life while maintaining the same audio quality. This also opens doors for new product ideas where BLE was not feasible due to battery life constraints. 

LE Audio Broadcast: How Does It Work in Real Life? 

To connect to an LE Audio Broadcast channel, one is required to connect to the desired audio broadcast. This puts constraints on the devices that don’t have Graphical User Interface, like earbuds. Also, to connect to an LE audio broadcast channel, one is required to scan for those channels, which is a power-hungry operation.  

To solve this problem, Bluetooth SIG came up with a solution to use an Assistant. An assistant is an application or native UI on your phone/laptop that provides support for scanning and connecting to the desired broadcast channels and redirecting it to your audio device like earbud. All the LE Audio Broadcasts should be as per the standards defined by Auracast™. Auracast™ broadcast audio is a set of defined configurations of Bluetooth® broadcast audio that are specified within the Public Broadcast Profile (PBP) specification of LE audio. 

Below are the simple steps required to connect to an Auracast™ broadcast audio: 

1. Scan your LE Audio enabled headset or earbuds with your phone and connect to it. In figure-1, audio device named BLEA-Broadcast_sink is connected to the phone. 
2. Click on the settings button given for the device BLEA-Broadcast_sink in figure 1. It opens a new window that looks like the image given in figure 2.  
3. Now click on “Listen to Auracast broadcast” button given in image 2. Enter the password when prompted. 
4. Once connected, you will see an image like the one in figure 3. You should be able to hear the broadcast audio now. The broadcaster’s name “Cine Broadcaster” is shown in figure 3. 

Applications of LE Audio 

1. LE Audio broadcast feature allows multiple devices to connect to the same audio stream. This feature has usage in multiple areas. 
   1. If your TV supports LE Audio broadcast, then all viewers watching the same TV can connect their headsets and listen to the same program on the volume they need. Multiple languages audio can also be supported if the TV has more than one Bluetooth channel. 
   2. You can connect to specific flight announcement requests and listen to them. This helps avoid loud audio announcements at the airports, railway stations, or bus stations. Moreover, announcements in many languages can be supported without creating unnecessary noise. 
   3.  In the Cinema halls, multiple audio streams can be supported in the same screen if the viewers are given headsets. This helps reduce the cost for playing movies on multiple screens, if the screens were just required because of audio language. 
2. LE Audio broadcast and low power consumption in LE audio allow for it to be used in the hearing aid applications. Earlier it was limited due to the battery life constraints. LE Audio also provides new profiles like HAP (Hearing Access Profile) and HAS (hearing Access Service) for the hearing aid solutions. 
3.  The LE Audio has also simplified the design of earbuds. Before the LE-Audio, the source could connect to only one earbud, which had to send the audio information to the other earbud. This required a complex code to be written to connect and synchronize the audio to the other earbud. The LE-Audio has introduced new profiles like Coordinated Set Identification Profile (CSIP) and service like Coordinated Set Identification Service (CSIS) to solve these problems. These profiles and services identify the member of the coordinated set like left and right earbud, ensures that the mute and volume control apply to all the members simultaneously and all members use the same audio source. 

 Conclusion 

As we saw above, the LE Audio and LE Audio broadcast are going to be the future of audio communication. They are expected to be used in many industries like retail, healthcare, travel, and entertainment. 

eInfochips provides Bluetooth implementation services including product development and testing for smart devices across various domains like retail, healthcare, travel, entertainment, and industrial automation. To know more about our services, please contact our experts today. 

References: 

LE Audio | Bluetooth® Technology Website