As the most important receiving component of GPS module, GPS antenna is the main window of GPS to the outside world. Speaking of GPS antennas, we have to mention the active and passive antennas we often talk about.
Passive GPS antenna is a ceramic body without circuit amplification. In other words, the antenna is directly connected to these pins of module. So its structure is simple. besides that, passive GPS antenna is mainly made of ceramic, and the ceramic is low cost, mature technology, and small space. It is suitable for GPS navigation products that emphasize compact spaces, such as Bluetooth, mobile phone GPS, and so on.
For GPS active antennas, there always is a distance between the device and the GPS module, so the received signal will be greatly attenuated. In order to compensate for the attenuation, the active antenna generally has at least two low noise amplifiers on the front of the antenna. The signal is amplified, and the amplified signal is output through the cable. The cable synchronously provides the DC voltage required by the LNA. because the signal is processed, including received and amplified in the active antenna receiver head, and it is far away from GPS equipment or other electrical appliances equipment, so there is minimum interference source for GPS active antennas.
Due to the extension of the antenna installation distance, the installation location can be selected in a very ideal environment. so the signal is often strong in actual use. especially when the signal is weak, the boot also is usually faster. because the internal secondary amplification will also have a certain gain. but due to the internal secondary LNA, it will also consume a certain amount of power. Therefore, the cost of an active antenna is much higher than that of a passive antenna, and the installation is also very difficult.