The antenna part adopts a multi-feed point design and a completely symmetrical antenna structure, with a relatively stable phase center, reducing the influence of the antenna on measurement errors The antenna gain is high, the pattern beam is wide, and the receiving effect of low-elevation signals is good, ensuring that the satellite can be received normally in some severely obstructed occasions The noise amplifier part adopts pre- and multi-stage filtering schemes, which can effectively suppress strong out-of-band interference signals and that it can be used in harsh electromagnetic environments. Application field The four-system seven-frequency built-in measurement antenna is a built-in GNSS antenna that covers GPS L1/L2, BDS B1/B2/B3, GLONASS L1/L2, E1, E5b. High-precision requirements can be widely used in surveying and mapping, deformation monitoring, precise positioning, mobile mapping, construction machinery control, and precision agriculture. color:Green Material:PC+Metal Package Contents: 1 x RTK GNSS built-in antenna Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.