Method and associated device for preventing umts call setup in nearby mobile phones
AssigneeMotorola, Inc.
InventorsMICHAEL L. JOHNSON, AARON S. MADSEN
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Abstract
An interference device and method of interfering with signals from a UMTS base station in a particular area are disclosed. The interference device receives a signal from the base station intended for a mobile device to initiate a communication session. The interference device synchronizes to the S-CCPCH and alters the TCFI and/or the data in the data field of the slot so that it is not longer correct. Time-shifted copies of the altered signal are then multiplexed and transmitted to the mobile device as a jamming signal. The jamming signal is received by the mobile device and causes the mobile device to be unable to determine the data of the original signal from the base station.
Claims20
A method of scrambling a communication from a Universal Mobile Telecommunications Method (UMTS) base station, the method comprising:
- receiving a transmitted signal from the base station intended for a communication device during initiation of a communication session between the base station and the communication device, the transmitted signal containing a Secondary Common Control Physical Channel (S-CCPCH), the S-CCPCH formed of a frame of slots each having a Transport Format Combination (TFC) field containing a Transport Format Combination Indicator (TFCI) and followed by a data field containing data;
- determining characteristics of the S-CCPCH;
- altering the characteristics of the S-CCPCH to produce an altered signal;
- and
- transmitting a jamming signal based on the altered signal to the communication device to interfere with the transmitted signal received by the communication device.
An interference device comprising:
- a receiver configured to receive a transmitted signal from a Universal Mobile Telecommunications Method (UMTS) base station, the transmitted signal intended for a communication device during initiation of a communication session between the base station and the communication device, the transmitted signal containing a Secondary Common Control Physical Channel (S-CCPCH), the S-CCPCH formed of slots each having a Transport Format Combination (TFC) field containing a Transport Format Combination Indicator (TFCI) and followed by a data field containing data;
- a processor configure to determine the TFCI of each slot and alter characteristics of each slot based on the determined TFCI to produce an altered signal;
- and
- a transmitter configured to transmit a jamming signal based on the altered signal to interfere with the transmitted signal.
Dependencies are inferred from the claim text.