radio frequency module
A radio module is a compact electronic transmitting/receiving device with which data can be transmitted by radio. Radio modules transmit on selected frequencies in free or licensed frequency bands and use the existing radio infrastructures, such as the established radio networks.
These can be short-range networks such as Bluetooth or ZigBee, but also mobile networks such as the GSM network, UMTS, Long Term Evolution( LTE) or 5th generation mobile networks( 5G).
In terms of structure, radio modules consist of the frequency-determining component, the quartz oscillator, the transmitter and receiver unit with antenna connection or antenna, a microcontroller as the control unit and the interfaces for the data to be transmitted and the power supply. In concept, radio modules are small circuit boards in the format of PCI plug-in cards, miniPCI plug-in cards or in the M.2 form factor. If they have to be particularly small, such as BLE radio modules, they can also be implemented as a system on chip( SoC). Radio modules have contact strips and are plugged onto larger circuit boards.
Functionally, radio modules transmit data from sensors or other functional units. These data are processed in the radio module, modulated, coded, amplified and transmitted via the antenna. The transmitting function is triggered by the reception of the sensor data.
The essential characteristics of radio modules include the frequency range, the number of channels and the width of the frequency channels, the reception sensitivity and the transmission power, as well as the data rate.