GPS antenna: description, purpose, characteristics

GPS-antenna is one of the most important elements of wireless infrastructure. From the correct choice and correct operation of these devices depends on the operability of the entire system, as they determine the maximum range of devices, the bandwidth of communication channels , etc.

Incorrectly mounted GPS-antenna in favorable weather conditions is able to provide a fairly tolerable connection, but during a rain or snowfall it will malfunction or cease to function at all. Despite the seeming simplicity, designing antennas sometimes requires more forces and means than creating complex electronic devices.

Classification of GPS-antennas is rather short. They are:

• Active and passive;
• External and board-mounted devices (by type of installation).

To date, there is a huge choice of antennas, but do not forget that no matter how reliable and powerful the device is, if a poor-quality GPS antenna is used with it, the technical characteristics of this system will be far from announced. The operation of such a device will not bring the user the expected result.

An active GPS antenna is a standard passive model with a built-in amplifier. Such devices are used in GPS-receivers, in which there are no internal devices, in this case a connector for the external antenna is output to the device case. Active devices outperform passive specimens in sensitivity, they increase the signal-to -noise ratio , reduce the effect of any kind of interference. The signal from passive antennas is strongly exposed to electromagnetic radiation, and as a result, reaches the receiver in a distorted and weakened state. The signal of active devices differs by a much larger amplitude than the passive ones. The choice of GPS-antenna should be approached individually, taking into account the type of receiver, because some devices can already contain a built-in antenna amplifier.

Manufacturers of GPS antennas offer a wide choice of external and internal antennas. They differ in voltage supply (3-5V), except signal amplifiers and bandpass filters, which cut out extraneous signals outside the required frequency range. GPS-antenna (automotive) operates at a frequency of 1575.42 ± 3 MHz. Taking into account the bandpass filter, the bandwidth of the transmitted band is 10 MHz. The average value of the antenna gain is 4 dB, the dissipated power is 1 W. Such devices are able to provide reliable operation in the temperature regime from -40 to +100 degrees Celsius with a relative humidity of 100 percent. The antennas are equipped with different types of cables, with different types of connectors, which allows them to be used with any type of receiver. The length of the cable can reach five meters, which makes it much easier to install the GPS-antenna.

To summarize, we note that modern devices are optimized for various criteria of solutions, such as high gain factors, low power consumption, low price, small overall dimensions.