Effects of GPS antenna performance is mainly the following aspects:

1, ceramic: ceramic powder and sintering quality directly affect its performance. The market is now using aceramic plate is 25 x 25, 18 x 18,

15 x 15, 12 x 12. Ceramic chip area is larger, the dielectric constant is bigger, its resonance frequency is higher, the better the effect of acceptance. Ceramic pieces are mostly square design,

In order to guarantee in the XY direction resonance are basically the same, so as to achieve uniform collectstar effect.

In 2, a layer of silver: ceramic antenna surface silver layer can influence the antenna resonance frequency.The ideal GPS ceramic chip frequency point accurately fall in 1575.42MHz, but the antenna

Frequency is very susceptible to impact on the environment, especially in the assembly, must by adjusting the silver surface coating profile, to modulate the frequency points to keep in

1575.42MHz. So GPS machine manufacturers in the procurement of antenna must be combined withantenna manufacturers, provide samples for testing.

3, feed point: ceramic antenna through a feed point collection resonance signal and sent to the rear.Because the antenna impedance matching causes, generally not in the antenna feed point

The center, but in the XY direction to do fine adjustment. The impedance matching method is simple and nocost increase. Only in one direction moving said

For the partial single antenna, in two axes are mobiles called double deflection.

4, amplifying circuit: bearing ceramic antenna PCB shape and size. Because GPS has a reboundcharacteristics, when the background is 7cm ×7cm continuous large

, patch antenna performance can play to the extreme. Although the appearance of the structure and other factors, but try to keep a considerable area and uniform shape. Amplification

Circuit gain selection must back-end LNA gain. Sirf GSC3F request signal input prior to the total gain of not more than 29dB, otherwise the signal saturation will

Self excited.

The GPS antenna have four important parameters: gain ( Gain ), wave ( VSWR ), noise coefficient (NoiseFigure ), axial ratio ( Axial ratio ).

With particular emphasis on the axial ratio, which is a measure of the different direction signal gaindifference index.

Because the satellite is randomly distributed in the hemisphere sky, so to ensure that the antenna on eachdirection all have similar sensitivity is very important. Axial ratio by day

Linear structure, appearance, the internal circuit and EMI effect.

Editor this paragraph GPS antenna selection

Most manufacturers from home and abroad to buy Ceramic parts, with the design of amplification circuit.Super intelligent terminal has become more and more represent the general trend, narrow space

The parts size raised very tall requirement. At present the domestic technology only in the 15 x 15 or 10 x 10 or more mature, mature basically. Smaller antenna needs

Imported.

Sub record antenna factory continued development and learning model GPS antenna, an external GPSantenna, we have more than 10 appearance, available to customers under the installation is not

The same needs to choose the relevant dimensions, record antenna factory in GPS/GSM combinedantenna has also made gratifying achievements, the current Asian record antenna factory developed in addition to

GPS/GSM dual-frequency antenna, and GPS/GSM/WIFI three frequency combination antenna,appearance and diverse, while the GPS built-in ceramic patch antenna we mature

The products are 25 x 25, 18 x 18, 15 x 15, is to focus on less than 15× 15 dimensions of the antenna, in order to better meet customer demand.