What is the function of the antenna on the Bluetooth module?

1、 Overview of Bluetooth module antenna

When it comes to Bluetooth module, one thing I have to mention is antenna. What is the antenna? Antenna is a component used to transmit or receive electromagnetic waves. The main function of transmitting antenna is to effectively convert the high-frequency current energy of the transmitter into space electromagnetic energy; The role of the receiving antenna is just the opposite, so the antenna is essentially an energy converter.

The Bluetooth module can successfully complete short-distance data transmission without considering the use position or direction, but the appropriate Bluetooth antenna design will help to achieve better transmission quality. For example, take two kinds of common antennas of Bluetooth module on the market: external antenna of IPEX interface and antenna on PCB board for comparison.

2、 Bluetooth module antenna comparison

The external antenna of IPEX interface is characterized by good directional directivity of signal, high efficiency and strong anti-interference ability. It can be far away from the interference on the main board without too much debugging and matching. As a terminal manufacturer, it only needs to connect an IPEX antenna outside; Of course, there are also disadvantages: high cost and troublesome assembly.

As a Bluetooth antenna, PCB on-board antenna refers to the part on the PCB for wireless reception and transmission. When transmitting, it converts the high-frequency current of the transmitter into space electromagnetic wave; When receiving, it converts the electromagnetic wave intercepted from space into high-frequency current and sends it to the receiver. Its characteristics are: less space occupation, low cost, no need to assemble the antenna separately, not easy to touch and damage, and convenient assembly of the whole machine.