U-blox Rolls Out Compact Triple-Band Antenna for High-Precision GNSS

U-blox has introduced the ANN-MB3, a compact triple-band GNSS antenna that supports the L1, L2, and L5 frequency bands. Measuring just 62 mm x 80 mm x 25.5 mm, the antenna has been engineered to meet the rising demand for high-precision real-time kinematic (RTK) positioning in applications with space and weight constraints, including drones, autonomous ground vehicles, smart agriculture equipment, and mobile robots.

The ANN-MB3.

While shrinking the size of a GNSS antenna typically risks compromising signal performance, the ANN-MB3 preserves high gain and reliability through a combination of internal design optimizations. These include an integrated ground plane, embedded low-noise amplifier (LNA), and pre-filters that boost signal clarity while suppressing unwanted noise and interference. By doing so, U-blox has made it possible to bring robust RTK-grade GNSS performance to mass-market devices without requiring bulky external antennas or multi-board designs.

Engineered for Seamless Integration

Ease of integration has been a core design goal for the ANN-MB3 (datasheet linked). The antenna includes an LTE Band 13 notch filter in the L1 signal path, which mitigates out-of-band interference from nearby cellular networks. This feature is especially useful in automotive and urban deployments where LTE signals often interfere with GNSS bands. By embedding this filtering directly into the antenna, U-blox eliminates the need for additional RF filtering on the device’s main PCB.

Block diagram of the ANN-MB3. 

The antenna also comes with a five-meter shielded coaxial cable and an SMA connector, pre-configured for plug-and-play installation. Multiple mounting options—including magnetic, adhesive, and screw-based configurations—allow developers to attach the antenna easily to a variety of surfaces. These features help reduce the overall system complexity and make the ANN-MB3 suitable even for teams without deep RF engineering expertise. 

Optimized for the ZED-F20P Platform

The ANN-MB3 has been specifically optimized to work with U-blox’s ZED-F20P, a triple-band GNSS module from the F20 high-precision platform. When paired together, the antenna and receiver form a highly synchronized positioning solution that can deliver centimeter-level accuracy with short convergence times and strong resistance to multipath interference.

The use of all three major GNSS frequency bands—L1, L2, and L5—allows the system to track more satellites simultaneously and extract more accurate positioning data. L5 in particular offers improved signal strength and better performance in dense urban environments or under foliage. Because the ANN-MB3 is matched to the RF characteristics of the ZED-F20P, developers benefit from simplified integration and consistent, validated performance right out of the box.

The ZED-F20P. 

In addition to the F20 module, the ANN-MB3 is also fully compatible with the U-blox F9 receiver family, which supports multi-frequency GNSS and is widely used in precision applications. This cross-compatibility means developers can standardize on a single antenna across product lines, reducing SKU complexity and long-term support costs.

Bringing Precision GNSS to More Applications

High-precision GNSS has historically been limited to specialized industries due to the size, complexity, and cost of associated hardware. With the ANN-MB3, U-blox is aiming to lower these barriers and enable broader adoption of precision positioning. The antenna’s rugged, compact, and pre-configured design is well-suited for environments where traditional GNSS hardware might fail or be difficult to integrate.

Applications range from centimeter-accurate row guidance in agriculture to precision docking for mobile robots and lane-level vehicle positioning in advanced driver-assistance systems (ADAS). The combination of high performance, ease of integration, and a competitive price point positions the ANN-MB3 as a practical solution for scalable GNSS deployment.

By extending its GNSS antenna portfolio with a fully integrated triple-band option, U-blox gives developers the flexibility to build advanced positioning solutions without being constrained by size or engineering resources. The ANN-MB3 marks an important step in making high-precision location services more accessible for mass-market products, and in doing so, it helps close the gap between cutting-edge GNSS capability and real-world deployability.

All images used courtesy of U-blox.