In earlier implementations, the radio transmission power played a crucial role in extending the range of Bluetooth Low Energy (BLE) modules. After the introduction of Bluetooth modules based on Nordic solutions, users gained access to improved communication protocols. These Bluetooth modules support BLE 4.2/5 protocols, with Bluetooth 5.0 and later versions offering a Long Range mode. This long-range wireless module design provides impressive power efficiency while achieving a coverage range exceeding 1 km.

Within these wireless communication devices, both Wi-Fi and Bluetooth modules communicate through serial ports to achieve transparent data transmission. The long-range module helps extend the Bluetooth connection's range, enabling enhanced localization. It also supports strong communication in areas where previous wireless devices faced obstacles. Furthermore, Long Range supports transparent signal transmission.

Factors Affecting BLE’s Ability to Achieve Over 1 km Range

Achieving a range greater than 1 km with BLE depends on the surrounding environment, antennas, and the performance of the radio signal. Several factors affect the Bluetooth range performance, including:

  • Antenna

  • Physical obstacles in the data transmission path

  • Receiver sensitivity

  • Transmitter output power

The BLE technology itself imposes limitations based on modulation methods. Since the performance of antennas and radios tends to be relatively static for specific Bluetooth devices, variations in the surrounding environment have a significant impact. For example, users may achieve up to 100 meters of range outdoors, which is a rare case. In indoor environments with obstacles like concrete walls, radio signals are weakened, significantly reducing the effective range.

When designing Bluetooth devices, manufacturers can choose to optimize the range by selecting Bluetooth chips with the best receiver sensitivity. Additionally, the output power should ensure the device has a good antenna. However, in certain cases where data needs to be transmitted over hundreds or even thousands of meters, different networks are used to achieve a greater range for Bluetooth modules.

Differences in Transmission Distances Across Bluetooth Protocol Versions

With the development of BLE 5.0, significant improvements in communication distance were achieved. So, what changes did Bluetooth 5.0 bring to make such progress? The Bluetooth specification version 5 includes several key improvements, such as:

  • "Long Range" 125 kbps or 500 kbps modes allow users to extend the range with relatively low data rate costs. The enhanced modes also result in lower average current consumption.

  • "High Speed" 2 Mbps mode allows users to increase the data rate or reduce average current consumption at the cost of range reduction.

  • Advertising extensions significantly improve data throughput for broadcast applications (such as beacons), up to 8 times higher than previous versions.

  • The maximum output power has been increased from +10 dBm to +20 dBm, enabling the use of more powerful amplifiers, further improving the range.

  • A new Channel Selection Algorithm (CSA2) was introduced, allowing more devices to coexist in the same environment without interference.

Specific Application Directions for Long Range

The Long Range mode (encoded PHY, 500/125 kb/s) provides higher data rates and modulations with stronger signal levels. Moreover, using the remote PHY option, the possibility of achieving better range within BLE increases. The key point is that the remote functionality requires both radios to support the encoded PHY function. The data rates quoted above include packet overhead, additional data, and headers. The goal is to reduce the raw data rate, effectively enhancing the range of user data.

The E104-BT5011A Bluetooth module is a master-slave integrated Bluetooth module based on Bluetooth protocol version 5.1. It is compact, low-power, and uses the encoded PHY for Long Range mode in Bluetooth 5. By incorporating the encoded PHY, this Bluetooth module offers remote coverage from 50 to 70 meters for connections up to 1 km. Expanding the range may require some hardware modifications.

To enhance performance, Bluetooth module designers have increased the sensitivity level of the receiver end. In some cases, even remote Wi-Fi routers cannot connect to wireless tools to extend the Wi-Fi range. Therefore, to achieve optimal results, world-class LBS solution providers offer high-quality R&D in positioning and wireless connectivity technology.