Patent EA-001925-B1 (EA)
Title: Radiotelephone filtering apparatus
IPC: H04W48/04
Filed: 1998-06-02
Abstract: 1. An apparatus for partial or total neutralization a capacity of receiving and transmitting radiotelephones or radiomesage receivers in a predetermined space, characterized in that said appararus comprises at least a transmitter, adapted to transmit signals of frequencies similar to those utilized for communication between radiophones or radiomessage receivers and a base station with which they can communicate, wherein this transmitter comprises means permitting to modify information containing in signals transmitted or received by radiotelephones or radiomessage receivers or base stations. 2. The apparatus as claimed in claim 1, characterized in that comprises additionally a receiver to detect radiotelephones present in the zone to be protected and adapting the character and a signal capacity transmitted by the device. 3. The apparatus as claimed in claim 1 or 2, characterized in that comprises a receiver for radio communication with the base stations. 4. The apparatus as claimed in claims 1 to 3, characterized in that comprises a transmitter for radio communication with the communication with the base stations. 5. The apparatus as claimed in claims 1 to 4, characterized in that at least one selective antenna is used for localized transmission on radiotelephones or detecting radiotelephone locations. 6. The apparatus as claimed in claim 5, characterized in that selective antennae are distributed in space to be protected depending on its geometry. 7. The apparatus as claimed in claim 5, characterized in that selective antennae are antennae directed by an angle. 8. The apparatus as claimed in claim 5, characterized in that a distributing selective antenna is an antenna of an emitting cable type. 9. The apparatus as claimed in claims 1 to 8, characterized in that transmitters and receivers as well as antennae can be different or multistandard or multiple for frequency ranges or radiotelephone standards to be filtered. 10. The apparatus as claimed in claim 6, characterized in that an existing electrical network is used for communication with said distributing antennae. 11. The apparatus as claimed in claims 1 to9, characterized in that comprises selective antennae for detection and/or neutralization or reactivation of radiotelephones in a predetermined zones of transitions from one zone to another. 12. The apparatus as claimed in claims 1 to 11, characterized in that it is designed enabling to transmit a permanent signal of interference in the direction of radiotelephones. 13. The apparatus as claimed in claims 2 to 11, characterized in that it adapted to be able to detect the presence of radiotelephone of radiotelephone transmissions and direct an intermittent signal of interference to the moment of a ring or a call. 14. The apparatus as claimed in claims 3 to 13, characterized in that it is adapted to be able to receive the station signals and to adjust the intensity of a signal and its nature with modification of information or service codes retransmitted to radiotelephones. 15. The apparatus as claimed in claim 4 or 13, characterized in that it adapted to be able to transmit intermittent signals to active radiotelephones and encoded signals to base stations warning of interference formation. 16. The apparatus as claimed in claim 4 or 13, characterized in that it adapted to be able to receive the station code before a radiotelephone is jammed. 17. The apparatus as claimed in claims 2 to 11, characterized in that it adapted to be able to detect a radiotelephone and transmitting a code to the base station for performing filtering without transmitting a signal to a mobile telephone. 18. The apparatus as claimed in claim 17, characterized in that it adapted to be able to transmit a filtering code on a mobile telephone as well. 19. The apparatus as claimed in claims 1 to 18, characterized in that it adapted to be able to transmit radio signals only to signalization channels. 20. The apparatus as claimed in claims 1 to 19, characterized in that it adapted to be able to be identified by the radiotelephone network, due to the identification codes in its memory. 21. The apparatus as claimed in claims 1 to 4, characterized in that it adapted to be able to function as a relay for the station , including for the communication channels. 22. The apparatus as claimed in claims 1 to 21, characterized in that comprises one receiver for detecting available or active radiotelephones, characterized in that comprises means or antennae of selective detection: either by an angle, or distributed, or in the form of emitting cable, or positioned proximitely, or on the main entrance.