Transportable device (100;300) which implements a private mobile radio communication network infrastructure, comprising: - a housing and, in this housing; - a radio head having at least one socket for connection to a radio antenna; and - a computer system connected to the radio head and comprising at least one x86 microprocessor (122,124) and at least one memory (126,128,130,132) in which computer code is registered, this computer code being designed to be executed by the x86 microprocessor(s) (122,124) so as to implement: • a subscriber server of the infrastructure which is designed to list mobile terminals (222 1,222 2,222 3) authorized to connect to the infrastructure, • a base station module of the infrastructure which is designed to be connected via the radio head to any mobile terminal (222 1,222 2,222 3) listed in the subscriber server, • a service module of the infrastructure which is designed to offer at least one private mobile radio communication network service, and • a core network module of the infrastructure which is connected to the base station module and to the service module to allow each mobile terminal (222 1,222 2,222 3) connected to the base station module to communicate with the service module. the at least one private mobile radio communication network service comprises a press-to-transmit service; the infrastructure is compliant with the Long-Term Evolution standard, LTE, such that the core network module is an evolved Packet Core, the subscriber server is a Home Subscriber Server, and the base station module is an evolved NodeB, as defined in that standard; the computer code further implements a broadcast service which is an Evolved Multimedia Broadcast Multicast Service as defined in the LTE standard, this broadcast service being used by the press-to-transmit service. - a housing and, in this housing; - a radio head having at least one socket for connection to a radio antenna; and - a computer system connected to the radio head and comprising at least one x86 microprocessor (122,124) and at least one memory (126,128,130,132) in which computer code is registered, this computer code being designed to be executed by the x86 microprocessor(s) (122,124) so as to implement: • a subscriber server of the infrastructure which is designed to list mobile terminals (222 1,222 2,222 3) authorized to connect to the infrastructure, • a base station module of the infrastructure which is designed to be connected via the radio head to any mobile terminal (222 1,222 2,222 3) listed in the subscriber server, • a service module of the infrastructure which is designed to offer at least one private mobile radio communication network service, and • a core network module of the infrastructure which is connected to the base station module and to the service module to allow each mobile terminal (222 1,222 2,222 3) connected to the base station module to communicate with the service module. • a subscriber server of the infrastructure which is designed to list mobile terminals (222 1,222 2,222 3) authorized to connect to the infrastructure, • a base station module of the infrastructure which is designed to be connected via the radio head to any mobile terminal (222 1,222 2,222 3) listed in the subscriber server, • a service module of the infrastructure which is designed to offer at least one private mobile radio communication network service, and • a core network module of the infrastructure which is connected to the base station module and to the service module to allow each mobile terminal (222 1,222 2,222 3) connected to the base station module to communicate with the service module. the at least one private mobile radio communication network service comprises a press-to-transmit service; the infrastructure is compliant with the Long-Term Evolution standard, LTE, such that the core network module is an evolved Packet Core, the subscriber server is a Home Subscriber Server, and the base station module is an evolved NodeB, as defined in that standard; the computer code further implements a broadcast service which is an Evolved Multimedia Broadcast Multicast Service as defined in the LTE standard, this broadcast service being used by the press-to-transmit service.