European Radio Equipment Directive, 2014/53/EU - "RED Directive"

The use of the Internet and mobile communications has allowed to give added value, in terms of its level of connectivity, to the everyday products of our environment as well as industrial and transport products. The use of radio modules has opened a wide range of possibilities and options within the fields of:

• IoT ("Internet of Things").
• LoRa and LoRaWAN.
• Communications and infrastructures WiFi.
• 5G technology.
• GNSS (Global Navigation Satellite System, similar to GPS).
• Communications M2M.
• GSM-R systems for railroad.

But, when facing a new design of a radio module or a new integration of it into a larger system, questions may arise like the following ones:

• Where should we install the antennas? Do we place them at the ends of PCBs or better in the inner zone?
• Where should I or can I locate the equipment in the event that it should be located inside a larger system (such as a train or a car)?
• What type of antenna should I select for each application? Omnidirectional antennas, directives... What guidance should my PCB have to not affect radio broadcast/ transmission?
• And regarding receivers/ transmitters of my module? Should I take them away from the antennas? And if I have more than one module, does the distance between them and between their antennas matter?
• Which are the details and obligations of the RED Directive (Renewable Energy Directive) for having my equipment as CE marking?

Answering all these questions collectively is impossible. We will have to particularize depending on the radio service we want to offer and how we will integrate it into our product or system. However, if it is true that making a mistake in a design definition can cause communication benefits to be appalling, with constant losses of coverage, errors in frames sent or incorrect GPS positions, which will eventually lead to the failure of the product, the system or its integration as part of a larger system.

Hence, during design phase and during the realization of first prototypes, accompanied by design of the product, there are some preventive measures that will allow us to detect errors in our design and be able to improve them in order to avoid product failure.

The type of measurements to be carried out normally are separated into the 2 following types:

Passive measures (Radio module not powered):

• Antenna impedance per service (e.g. GPS, LTE, LoRa, WIFI, BT).
• Isolation between antennas and service (for instance Telephony - GPS, Telephony -WIFI/BT, WIFI/BT - GPS).
• Analysis of the effect of wiring and connection being close to the module on the antennas, especially those which operate at the lowest frequency.
• Analysis of the effect of integration of the radio module in its final performance condition (installation in a vehicle or train, mechanical encapsulation, etc.).

Active measurements (powered radio module):

• Measurement of system sensitivity. Detecting which is the minimum power the module can work with a minimum quality criterion.
• Measurements of noise bases at input of the receivers. Interference effect with nearby elements.
• Measures of maximum power radiated by the module. Detecting which is the maximum power the module can radiate and, thus, being able to estimate its range.

All these measures are necessary to ensure the proper functioning of the equipment and compliance with RED directive.

Leedeo offers you the accompaniment and all the necessary advice to be able to successfully overcome the RED directive standards and successfully approve your equipment with radio modules. Feel free to contact us >>