GNSS Flex pHAT with mosaic-X5 RTK & IM19 IMU

Jargon buster

Plain-language definitions for the technical terms used above.

B1I

A BeiDou satellite signal used for standard positioning. It matters because the receiver must support the signal bands used by a constellation to take advantage of those satellites.

B2a

A BeiDou satellite signal used by newer dual-band GNSS receivers. Support for B2a can improve accuracy and reliability when combined with other GNSS bands.

BDS

BeiDou, China’s satellite navigation system. Support for BDS gives the receiver access to more satellites, which can help maintain a better position fix in challenging locations.

CLK

CLK is the clock signal that times when SPI data bits are sent and read. A display needs this pin connected correctly so the controller and screen stay in step while data is transferred.

E1

A Galileo satellite signal band used for standard positioning. Knowing which signal bands are supported helps you judge compatibility and expected performance of a GNSS receiver.

E5a

A Galileo satellite signal band used for higher-performance positioning services. Support for E5a can help dual-band GNSS receivers improve accuracy and reduce errors from atmospheric delay.

EGNOS

Europe’s SBAS service for improving GNSS positioning accuracy and reliability. It is relevant if the receiver will be used in Europe or nearby supported areas without an RTK correction link.

GAGAN

India’s SBAS service for improving GNSS positioning. It matters for projects in its coverage region because it can improve standard GNSS accuracy when RTK is not being used.

Galileo

Europe’s satellite navigation system. Galileo support can improve satellite availability and accuracy, especially when combined with GPS and other constellations.

GLONASS

Russia’s satellite navigation system. A receiver that can also use GLONASS has more satellites to choose from, which can improve positioning reliability when the sky view is partly blocked.

GNSS

GNSS stands for Global Navigation Satellite System, covering positioning systems such as GPS and similar satellite networks. It matters here because high-precision GNSS modules can output lots of serial position data that this product can send wirelessly to a computer or phone.

GPIO

General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.

GPS

The US satellite navigation system used by GNSS receivers to calculate position and time. Support for GPS is important because it is widely available and often used together with other constellations for more reliable positioning.

Gyroscope

A gyroscope measures rotation, such as how fast a board is turning around its X, Y, and Z axes. This matters for projects like gesture controls, balancing robots, and motion tracking where tilt or rotation changes need to be detected.

Headers

Rows of metal pins used to plug a module into a breadboard or connect it with jumper wires. Pre-soldered headers make the module easier to use straight away without needing to solder the pins yourself.

I2C

I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.

IMU

An Inertial Measurement Unit combines motion sensors to measure movement and orientation. It matters for asset tracking because it can detect movement, tilt, vibration, or changes in direction.

L2C

A second GPS signal band used by dual-band GNSS receivers to improve precision and reduce errors caused by the atmosphere. It matters for RTK and high-accuracy applications because using two bands can produce faster and more reliable centimetre-level fixes.

L5

A modern GNSS signal band used by several satellite systems for more accurate and robust positioning. Dual-band receivers that include L5 can often perform better than single-band receivers, especially for RTK and areas with reflected signals.

LED

A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.

microSD card

A microSD card is a small removable memory card used to store files such as audio tracks. For this product, the card is where the sound files live, so its capacity and formatting can affect how many sounds you can use.

MSAS

Japan’s SBAS service for improving GNSS positioning. It is useful to know because SBAS benefits depend on whether your project is located in the service’s coverage area.

native USB

Native USB means the microcontroller itself handles USB communication, rather than using a separate USB-to-serial chip. This matters for programming, debugging, and projects that need the board to act directly as a USB device.

pHAT

A smaller add-on board format for Raspberry Pi, similar in idea to a HAT but usually not full-sized. It matters because pHAT compatibility can affect how neatly a board stacks or fits into a Raspberry Pi project.

PVT

Position, velocity and time data reported by a GNSS receiver. Knowing the PVT update rate helps you judge how often the board can provide basic navigation information to your project.

Qwiic

Qwiic is a plug-in connector system for I2C devices that uses small 4-pin cables, so you can connect compatible sensors without soldering. It matters because your controller or adapter also needs Qwiic, or you will need a cable or breakout to wire it up.

QZSS

Japan’s regional satellite navigation system designed to improve coverage around Japan and the Asia-Pacific region. QZSS support can improve satellite availability in supported regions when used alongside GPS.

RTK

Real-Time Kinematic positioning is a GNSS technique that uses correction data from a base station to greatly improve location accuracy. It matters if you need centimetre-level positioning for robotics, mapping, surveying, or tracking rather than ordinary metre-level GPS accuracy.

SBAS

Satellite-Based Augmentation System, a set of regional services that broadcast correction information for GNSS receivers. SBAS can improve ordinary GPS-style positioning, although it is not the same as centimetre-level RTK correction.

single-board computer

A complete computer built onto one circuit board, usually including the processor, memory, ports, and connectors. This matters because accessories like heatsinks must match the board’s layout and mounting holes to fit properly.

SMA

A threaded coaxial connector commonly used for antennas. It matters because you need antennas with matching SMA connectors, or suitable adapters, for the LTE and GNSS antenna ports.

u.FL

u.FL is a tiny snap-on antenna connector often used on compact wireless boards. A board with u.FL usually needs an external antenna, which matters if the product will be inside an enclosure or needs better antenna placement.

UART

UART is a simple serial connection that sends data over separate transmit and receive wires, often labelled TX and RX. It matters because this module is designed to replace a wired UART cable with a wireless link while keeping the same serial data format.

USB-C

A modern reversible USB connector used for power and data connections. On this product it matters because it can connect directly to a computer as well as to a microcontroller project.

WAAS

A North American SBAS service that provides correction data for GNSS receivers. It matters if you are using the product in a supported region and want better non-RTK positioning accuracy.