The Origin of Bluetooth Anti-Loss Tracker

"Where is my key?" "Where is my wallet?" "Where is my mobile phone? Call me quickly." It is easy to put things at will, but it is more difficult to find out. We often encounter similar situations in our daily life. Anti-loss trackers can help a lot. And Bluetooth low energy technology is an important enabler behind it.

Continuous improvement of BLE technology make anti-loss trackers less and less power consuming. And their ownership cost has also been dramatically driven down. Thus, more and more derivative applications got cranked out on top of it.

Making of Bluetooth Anti-Loss Tracker

A Bluetooth anti-loss tracker is a device designed on basis of identification, ranging and positioning capabilities of the BLE technology. While coupled and supported with a dedicated smartphone App, the trackers can be sticked to some important items either personal or public so as to ensure they are in a range where the user can easily track with the App. Such trackers are normally used to wirelessly tag daily necessities such as keys, wallets, mobile phones, suitcases and backpacks. They are also used to avoid loss incidents of kids, senior citizens or pets.

The following is the reference scheme of the Bluetooth anti-lost tracker based on the RF-BM-BG22C3 Bluetooth module of Shenzhen RF-star Technology. It realizes the two-way search function between the tracker tag and the mobile phone. The block diagram of the device is shown in Figure 1.

Figure 1 The Block Diagram of Bluetooth Anti-Lost Tracker

Essentials

1) Based on the connection, the phone APP sends an alarm command to the anti-loss tracker. After receiving the command, the tracker makes the corresponding pin output at a specific frequency, drives the buzzer to emit a beep, and the LED flashes according to the same frequency. On the contrary, if the command is sent to the mobile phone through the tracker, then the mobile phone makes the corresponding vibration or ringing prompt. More button functions can be self-defined.

2) The initial connection between the mobile phone and the anti-loss device needs to be paired, and the subsequent connection is non-inductive automatic connection (except for deleting the pairing). In daily life, the mobile phone and the anti-loss device will be disconnected due to reasons, but when the mobile phone Bluetooth is again in the effective signal range of the anti-loss device, it will automatically initiate a connection to the paired device, simplify the process, and achieve reconnection without manual operation.

3) The power consumption control is important since the anti-loss tracker is powered by a coin battery with a small size. Increasing the connection and broadcast interval will conduct the tracker to be in a long sleep time, thus reducing power consumption. The specific parameters should be adjusted according to the actual application, the connection effect, response speed, and other requirements, so as to achieve the purpose of satisfying the experience, saving power consumption, and extending the life span.

4) The following functional sections can be designed: APP, self-defined the UI function interface, and mobile peripheral to drive the mobile peripherals. The APP interface can be combined with the BLE protocol to achieve the data sending and receiving.

5) For the hardware part of the anti-loss device, adopting the module or chip is according to the requirements. Referred to the above reference design, only three GPIOs are used, one input pin is connected to the key, and two output pins are connected to the buzzer and LED respectively.

The above cases are mostly applied indoors to realize rapid and accurate mutual inspection and mutual search according to specific needs. For the outdoor anti-loss applications of special crowds, RSSI combined with a positioning algorithm can be used to judge, so as to realize the early warning and prompt function.

Advantages of BLE

1）Ultra-Low Power Consumption and Long Service Life

Developing from BLE 4.0 to the popular BLE 5.3, the technology has grown more and more mature. Although the features continue increased and optimized, ultra-low power consumption is still an eternal theme.

BLE modules from RF-star minimize the power consumption by the intelligent design and technologies, so that the products are with lower peak power consumption, average power consumption, and standby power consumption. In many scenarios, a coin battery can be directly used for power supply, which also meets the service life requirements of Bluetooth anti-loss trackers.

The RF-BM-BG22C3 BLE modules, based on the EFR32BG22 SoC from Silicon Labs, were launched by Shenzhen RF-star Technology. The power consumption is about 15 µA under the conditions of 0 dBm transmit power and 1 s broadcast cycle, and the sleep power consumption is as low as 3-4 µA. In outdoor scenario, with physical layer rate of 1 Mbsps and the maximum transmission power of +6 dBm, its communication range can reach around 135 m. It perfectly supports the application of Bluetooth anti-loss trackers. For more information on BLE modules, welcome to visit our website of www.rfstariot.com.

2）Downward Compatibility and OTA Upgrade

The downward-compatible update mechanism of BLE is conducive to the software update of Bluetooth products. While a new release is developed on basis of an existing firmware, one can upgrade the device wirelessly with OTA (Over the Air) function to avoid the hassle  of disassembling modules and returning to the factory for burning, which greatly saves time and labor, thus improves the development and maintenance efficiency.

3）Low Cost

BLE has been widely used in various fields of IoT. Point-to-point communication between devices is basically based on BLE technology. Compared with Wi-Fi, Zigbee, Thread, and other networking technologies, BLE cost much less from the perspective of hardware deployment and software development.

4）One-Stop Development Solutions

Not only BLE technology is rapidly developing, RF-star also improves the development ability day by day. We have accumulated rich experience in software and hardware development so that we provide a one-stop service from the initial module selection to the subsequent scheme design and development. Customers can directly use the BLE module to realize the wireless communication on the original product without understanding the BLE protocol, which can reduce the difficulty of product development and shorten the time to market.

Current Status and Trend

At present, there is a huge quantity of Bluetooth anti-loss trackers in the market, which have simple and similar functions. With the development of wireless technology, anti-loss devices continue to develop in the direction of accurate location, cloud servers, map service, and voice service. Apple, Huawei, and Xiaomi have also launched a series of anti-loss products according to their respective product ecology. In view of the advantages of low cost, low power consumption, small size, and mature technology, Bluetooth anti-loss products still have a wide development space.

About RF-star Technology

Shenzhen RF-star Technology Co., Ltd. (RF-star) is a high-tech company focusing on radio frequency devices and has been certified by Texas Instruments as a third-party IDH of low-power RF products for more than a decade. RF-star provides IoT wireless modules and a full set of solutions, including BLE, Wi-Fi, Matter, Wi-SUN, Sub-1G, ZigBee, Thread, etc. For more information, kindly visit the official website https://www.rfstariot.com/or contact us at info@szrfstar.com.