Bluetooth 5 is bold. It’s trending. And it’s triggered a new wave of excitement for Bluetooth developers because of the plethora of devices that can be controlled from devices like smartphones (see figure). Now that we’ve watched the confetti fall from this big launch, let’s sift through the details to debunk the biggest myths of Bluetooth 5.
1. Bluetooth 5 isn’t backwards-compatible with legacy Bluetooth devices.
The beauty of Bluetooth 5 is that it’s completely backwards-compatible with Bluetooth 4.0, 4.1, and 4.2 devices. Another added benefit is that you can apply all of the features of legacy Bluetooth core specifications to Bluetooth 5. For example, you can use the data-length extensions from Bluetooth 4.2 in conjunction with the high speed of Bluetooth 5 to leverage an optimal feature set for your design.
2. Bluetooth 5 has higher speed and longer range.
One of the biggest misnomers about Bluetooth 5 is the idea that users can operate at 2 Mb/s with extended range, which isn’t the case. The high-speed and long-range features are at opposite ends of a spectrum: You must choose whether data rate or range is most important, because a device can’t operate in both modes at the same time. For instance, to achieve maximum range, you must sacrifice the data rate, which drops to 125 kb/s.
3. Bluetooth 5 long range is achieved by increasing the output power of the radio.
A big advantage of long-range modes is that there’s no increase in power consumption. By using coded physical layers (PHYs), receiver sensitivity improves while maintaining the same transmit (TX) and receive (RX) current as Bluetooth 4.0, 4.1, and 4.2. Bluetooth 5 uses forward error correction (FEC) to expand the payload data bits 1-to-2 or 1-to-4 at data rates of 500 kb/s or 125 kb/s, respectively. The receiver can now more readily distinguish between a signal and noise.
4. Bluetooth 5 includes Bluetooth Low Energy (BLE) mesh.
Countless Bluetooth developers were eagerly awaiting the ratification of BLE mesh with Bluetooth 5. To the surprise of many, BLE mesh was released independently, and after the announcement of Bluetooth 5. This is a subtle but important fact –BLE mesh is outside the core Bluetooth specification. This means that you can use mesh in conjunction with Bluetooth 4.0, 4.1, 4.2, or 5.