What is ACROPOL within the Police?

The ACROPOL network was originally developed by the company Airbus Defence and Space, part of the Airbus group and installed in all services since 1994.

It is part of the INPT (National Shareable Transmission Infrastructure) which is the national digital radiocommunication network. It is intended to ensure interoperability of emergency services, i.e., exchanges between police, gendarmerie, firefighters, SAMU, Civil Security. This radio network operates in the 380-410 MHz band using TETRAPOL technology.

TETRAPOL is a digital radiocommunication standard, mainly implemented in equipment used by security forces.

The INPT is used by ACROPOL (police), ANTHARES (firefighters) and RUBIS (Gendarmerie) for civil security operations.

Table of Contents:

• Presentation
• Future Radio Network

ACROPOL is a unique and national radio network, allowing a user, from anywhere in the territory, to access all services whether through a fixed station or one installed in a vehicle. Conversely, each officer can be reached anywhere by simply dialing their station number.

The advantages of ACROPOL are based on:

• the voice clarity of the message (cannot be intercepted by third parties outside the ACROPOL network)
• high confidentiality due to encryption
• the ability to trigger an emergency call in case of distress by pressing a simple button.

When establishing a communication, the Information and Command Center (CIC) decides to activate a radio channel called a conference. Each open conference is assigned an identification number. Field agents' radios are recognized through continuous communication. 

Each conference operates in trunking mode (Secure calls limiting the risk of disconnection): during transmission, it can be shared in time on the same TRX channel (transmitter allowing multi-communication), however the frequency does not change periodically like the frequency hopping of certain public GSM networks. If the police officer changes geographic sector and passes under the antennas of a new relay, there is no handover, but a search is performed on the beacon channel. Only tactical voice communications between handsets do not use the relay trunking process since the communication is interpersonal.

Each officer can, through an onboard terminal (TESA) connected to the network, at the very site of a public road event, record and transmit all elements for action as well as archiving, thus establishing a "computerized logbook" without having to repeat this action upon returning to their service.

Acropol is part of the INPT along with RUBIS and ANTARES. 

Following emergency call outages, the INPT is undergoing changes, as it has been deemed disappointing and unreliable by users. The RRF (Future Radio Network) project aims to build a national high-speed priority mobile communication system.

This communication service must be operational by 2023 at the latest. Indeed, it is supposed to be in service during the Rugby World Cup in summer 2023 and then the Olympic and Paralympic Games in Paris in 2024.