Bluetooth Low Energy Module for Wireless Paak Solution

Compared with traditional automotive Bluetooth applications, Bluetooth low energy is emerging in a variety of new applications such as personalized vehicle interaction, cable replacement, and phone as a key (PaaK) keyless entry.

Cars come with 6 to 12 sensors. Automakers typically employ two types of PaaK solutions: unconnected and connected PaaK solutions.

In a connectionless PaaK, the in-car module is the observation device and the smartphone is the broadcast device. In connected PaaK, a direct connection is established between the smartphone and the car, but the driver needs to pair their smartphone with each sensor individually to take advantage of the app's full benefits

Car key Bluetooth low energy distribution:

• The entire Bluetooth system consists of a master module (red module) and a slave module (light blue module)
• The main module is arranged in the central control, the slave module is on the door, the main driver, the front engine cover and the rear trunk
• The main module mainly communicates with the mobile phone, exchanges keys, and unlocks
• The slave module mainly obtains the Bluetooth RSSI signal strength of the mobile phone

Bluetooth Low Energy Module Features:

1. From the perspective of Bluetooth master-slave, the master module is actually a Bluetooth slave device. It establishes a connection with the mobile phone, exchanges keys, and achieves the function of unlocking. At the same time, the master module needs to receive the broadcast from the slave module. Get the signal strength of the mobile phone RSSI, calculate the azimuth, distance and angle of the mobile phone, and open the lock of which door is close to it.

2. The connection between the slave module and the master module can be established or not, as long as the slave module can send the RSSI signal strength of the mobile phone to the master module in a timely and accurate manner. In addition, the slave module needs low power consumption function, after all, it is battery powered. It takes a long time to use, and at the same time, it needs to accept the wake-up message sent by the master module, that is, when the mobile phone is close to the car, the main module will connect with the mobile phone, and the master module will send a message to wake up the slave module, and after it wakes up, it will detect the orientation of the mobile phone in real time. and RSSI and active feedback to the main module.

3. The slave module under the main driver's seat is mainly to detect whether the mobile phone is in the car, whether it is within the allowable starting range of the car, and the one-key start function cannot be performed within the distance of starting the car.

4. The Master module needs to be connected to some Bluetooth car keys (similar to the traditional unlimited car keys) of the Bluetooth master to perform traditional functions such as unlocking and locking the car. Of course, the mobile phone APP also needs the same functions as traditional operations.

Wireless Paak Solution Technical Difficulties:

1. The Master module needs to be able to rely on which azimuth angle is provided by the slave module, how far the distance is, and which slave module is close to, and the error cannot exceed 0.5 meters.

2. The Master module is also a BLE module, but it is necessary to connect back and transmit the key when the mobile phone does not open the APP to achieve the purpose of unlocking.

3. The power consumption of the slave module needs to be low, and it generally requires two years of normal standby

4. The slave module needs to be able to be woken up by the master module without any link

5. The Bluetooth module is generally installed in the door handle or inside the central control, and the surrounding area will be surrounded by some metal, how to ensure the accuracy of the signal strength.

Shenzhen Huayang Xinke Electronics Co., Ltd has many Bluetooth Low Energy Modules, and it has a BLE module HY-BT401 for wireless Paak Solution. This module is BLE 5.1 module, with a built-in antenna. For more information, welcome contact us!