Selective wireless communication blocker

• US 20030143943A1
• Filed: 01/22/2003
• Published: 07/31/2003
• Est. Priority Date: 01/24/2002
• Status: Active Grant

• Current Assignee: PC-TEL Incorporated
• Original Assignee: Pctel Maryland Incorporated
• Inventors: Kline, Paul A.
• Granted Patent: US 7,050,755 B2
• Time in Patent Office: Days
• US Class Current: 455/1
• CPC Class Codes: H04K 2203/16 for telephony
• CPC Class Codes: H04K 2203/34 involving multiple cooperating jammers
• CPC Class Codes: H04K 3/41 characterized by the control of the jamming activation or deactivation time control of jamming activation and deactivation time only for the purpose of alternating between jamming mode and target monitoring mode H04K3/45
• CPC Class Codes: H04K 3/42 characterized by the control of the jamming frequency or wavelength
• CPC Class Codes: H04K 3/43 characterized by the control of the jamming power, signal-to-noise ratio or geographic coverage area
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
• CPC Class Codes: H04K 3/65 using deceptive jamming or spoofing, e.g. transmission of false signals for premature triggering of RCIED, for forced connection or disconnection to/from a network or for generation of dummy target signal
• CPC Class Codes: H04K 3/84 related to preventing electromagnetic interference in petrol station, hospital, plane or cinema
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment

Abstract

A selective blocker for targeted mobile terminals. A signal monitor determines when a targeted mobile terminal is transmitting a signal to a base station. A signal analyzer identifies characteristics of the terminal signal and a processor produces a blocking response based on one or more characteristics. The blocking response is transmitted to the targeted mobile terminal to block communications between the targeted mobile terminal and the base station using the minimum power needed to effectively block the terminal signal so as to limit interference with non-targeted mobile terminals.

Claims

1. A method for selectively blocking communication within a blocking zone, wherein the method comprises:

detecting from a targeted mobile terminal a call origination signal;

determining a blocking response tailored to the call origination signal;

transmitting a blocking signal comprising the blocking response; and

limiting the blocking signal to the blocking zone.

2. The method of claim 1, wherein transmitting a blocking signal comprising the blocking response comprises determining a range of probable frequencies of a response signal from the base station, and

wherein transmitting the blocking signal with sufficient power to achieve the blocking signal power at the call origination signal location comprises transmitting the blocking signal at each of the probable frequencies of a response signal with sufficient power to achieve the blocking signal power at each of the probable frequencies of a response signal at the call origination signal location.

3. A method for selectively blocking communication within a blocking zone, wherein the method comprises:

detecting from a targeted mobile terminal a call origination signal;

determining a blocking response;

transmitting a blocking signal comprising the blocking response; and

limiting the blocking signal to the blocking zone, wherein limiting the blocking signal to the blocking zone comprises;

determining a call origination signal location;

determining the power of a blocking signal measured at the call origination signal location necessary to block the call origination signal; and

transmitting the blocking signal with sufficient power to achieve the blocking signal power at the call origination signal location.

4. The method of claim 3, wherein transmitting the blocking signal with sufficient power to achieve the blocking signal power at the call origination signal location comprises transmitting the blocking signal from a plurality of transmitters wherein the cumulative strength of the blocking signal at the call origination signal location from the plurality of transmitters is substantially equal to the blocking signal power.

5. A method for selectively blocking communication within a blocking zone, wherein the method comprises:

detecting from a targeted mobile terminal a call origination signal;

determining a blocking response;

transmitting a blocking signal comprising the blocking response; and

limiting the blocking signal to the blocking zone, wherein limiting the blocking signal to the blocking zone comprises;

ceasing transmission of the blocking signal after expiration of a blocking period;

monitoring the targeted mobile terminal for a call origination signal; and

transmitting the blocking signal for the blocking period if the call origination signal is present.

6. A method for selectively blocking communication within a blocking zone, wherein the method comprises:

detecting from a targeted mobile terminal a call origination signal;

determining a blocking response;

transmitting a blocking signal comprising the blocking response; and

limiting the blocking signal to the blocking zone;

wherein determining the blocking response comprises determining a coding scheme of the targeted mobile terminal; and

wherein transmitting a blocking signal comprising a blocking response comprises transmitting a blocking signal comprising a code symbol wherein receipt of the code symbol by the targeted mobile terminal disrupts the coding scheme of the targeted mobile terminal so as to preclude the mobile terminal from processing a response signal sent by a base station.

7. The method of claim 6, wherein the code symbol comprises a time reference mark of the base station.

8. A selective wireless communication blocker comprising:

a monitor adapted to detect call origination signals transmitted by a targeted mobile terminal;

a signal analyzer connected to the monitor so as to receive the call origination signals from the monitor, wherein the signal analyzer analyzes the call origination signals to selectively identify a call origination signal generated by a targeted mobile terminal and produces targeted mobile terminal data based on the analysis;

at least one transmitter adapted to transmit a blocking signal when so instructed; and

a processor connected to the signal analyzer so as to receive the targeted mobile terminal data, the processor executing software instructions adapted to cause the processor to perform the steps of;

determining a blocking response tailored to the call origination signal; and

instructing the at least one transmitter to send a blocking signal comprising the blocking response, wherein the blocking signal is limited to a blocking zone.

9. The selective wireless communication blocker as in claim 8, wherein determining the blocking response comprises determining a range of probable frequencies of a response signal from a base station, and

wherein instructing the at least one transmitter to send a blocking signal comprising the blocking response wherein the blocking signal is limited to a blocking zone comprises instructing the at least one transmitter to transmit a blocking signal comprising the range of probable frequencies of a response from a base station.

10. A selective wireless communication blocker comprising:

a monitor adapted to detect call origination signals transmitted by a targeted mobile terminal;

a signal analyzer connected to the monitor so as to receive the call origination signals from the monitor, wherein the signal analyzer analyzes the call origination signals to selectively identify a call origination signal generated by a targeted mobile terminal and produces targeted mobile terminal data based on the analysis;

at least one transmitter adapted to transmit a blocking signal when so instructed; and

a processor connected to the signal analyzer so as to receive the targeted mobile terminal data, the processor executing software instructions adapted to cause the processor to perform the steps of;

determining a blocking response based on the received targeted mobile terminal data, and

instructing the at least one transmitter to send a blocking signal comprising the blocking response, wherein the blocking signal is limited to a blocking zone;

wherein determining the blocking response comprises determining a coding scheme used by the targeted mobile terminal, and

wherein instructing the at least one transmitter to send a blocking signal comprising the blocking response wherein the blocking signal is limited to a blocking zone comprises instructing the at least one transmitter to transmit a blocking signal comprising a code symbol wherein receipt of the code symbol by the targeted mobile terminal disrupts the coding scheme of the targeted mobile terminal so as to preclude the mobile terminal from processing a response signal sent by a base station.

11. The selective wireless communication blocker as in claim 10, wherein the code symbol comprises a time reference mark of the base station.

12. A selective wireless communication blocker comprising:

a monitor adapted to detect call origination signals transmitted by a targeted mobile terminal;

a signal analyzer connected to the monitor so as to receive the call origination signals from the monitor, wherein the signal analyzer analyzes the call origination signals to selectively identify a call origination signal generated by a targeted mobile terminal and produces targeted mobile terminal data based on the analysis;

at least one transmitter adapted to transmit a blocking signal when so instructed; and

a processor connected to the signal analyzer so as to receive the targeted mobile terminal data, the processor executing software instructions adapted to cause the processor to perform the steps of;

determining a blocking response based on the received targeted mobile terminal data,

instructing the at least one transmitter to send a blocking signal comprising the blocking response, wherein the blocking signal is limited to a blocking zone;

instruct the at least one transmitter to cease sending a blocking signal after a blocking period;

determine if the targeted mobile terminal is sending the call origination signal; and

instruct the at least one transmitter to transmit a blocking signal if the mobile terminal is sending the call origination signal.

13. A selective wireless communication blocker comprising:

a monitor adapted to detect call origination signals transmitted by a targeted mobile terminal;

a signal analyzer connected to the monitor so as to receive the call origination signals from the monitor, wherein the signal analyzer analyzes the call origination signals to selectively identify a call origination signal generated by a targeted mobile terminal and produces targeted mobile terminal data based on the analysis;

at least one transmitter adapted to transmit a blocking signal when so instructed; and

a processor connected to the signal analyzer so as to receive the targeted mobile terminal data, the processor executing software instructions adapted to cause the processor to perform the steps of;

determining a blocking response based on the received targeted mobile terminal data,

determining a call origination signal location,

determining the power of a blocking signal measured at the call origination signal location necessary to block the call origination signal, and

instructing the at least one transmitter to send a blocking signal to the call origination signal location, wherein the blocking signal is transmitted with sufficient power to achieve the blocking signal power at the call origination signal location.

14. A selective wireless communication blocker comprising:

a monitor adapted to detect call origination signals transmitted by a targeted mobile terminal;

a signal analyzer connected to the monitor so as to receive the call origination signals from the monitor, wherein the signal analyzer analyzes the call origination signals to selectively identify a call origination signal generated by a targeted mobile terminal and produces targeted mobile terminal data based on the analysis;

a plurality of transmitters adapted to transmit a blocking signal when so instructed; and

a processor connected to the signal analyzer so as to receive the targeted mobile terminal data, the processor executing software instructions adapted to cause the processor to perform the steps of;

determining a blocking response based on the received targeted mobile terminal data,

determining a call origination signal location,

determining the power of a blocking signal measured at the call origination signal location necessary to block the call origination signal, and

instructing the plurality of transmitters to send a blocking signal to the call origination signal location, wherein the power of the blocking signal from all transmitters is sufficient, at the call origination signal location, to achieve the blocking signal power.