Method and apparatus for heavy-tailed waveform generation used for communication disruption
The present invention has application to countering IEDs which are triggered remotely through a RF signal directed at, or the same operating environment as, receiver components embedded in, or part of, commercially manufactured cell phones or remote control devices. The invention exploits those situations where the underlying device (i.e., a commercial cell phone) is designed to operate in an environment where noise is characterized by an additive Gaussian noise model. The invention exploits the optimization of the matched filter for Gaussian noise by introducing a specific non-Gaussian noise. Further, the invention is directed to a family of jamming waveforms which exhibit increased effectiveness against a variety of digital and analog communications systems.
1. A wireless communications jamming device, comprising:
a heavy-tail noise generator for periodically generating a heavy-tail noise variable;
a register for storing the periodically-generated, heavy-tail noise variable;
a wideband noise generator for generating a wideband noise variable at a rate higher than that of the heavy-tail noise generator;
a multiplier configured to multiply the wideband noise variable with the stored periodically-generated, heavy-tail noise variable, and thereby generate a multiplied wideband output signal to be transmitted as a jamming signal; and
a censoring device for censoring according to a censoring threshold value the periodically-generated, heavy-tail noise variable generated by the heavy tail noise generator.
2. A wireless communications jamming device according to claim 1 , further comprising:
a limiting device for limiting according to a limiting threshold value the periodically-generated, heavy-tail noise variable generated by the heavy tail noise generator.
3. A wireless communications jamming device according to claim 1 , further comprising:
a filter for concentrating the multiplied wideband output into a band of a link to be jammed.
4. A wireless communications jamming device according to claim 1 , further comprising:
a frequency up-converter for shifting the multiplied wideband output signal to a predetermined RF frequency of a link to be jammed, so as to generate the jamming signal to be broadcast.
5. A wireless communications jamming device comprising:
a heavy-tail noise generator for periodically generating a heavy-tail noise variable;
a register for storing the periodically-generated, heavy-tail noise variable;
a wideband noise generator for generating a wideband noise variable at a rate higher than that of the heavy-tail noise generator;
a multiplier configured to multiply the wideband noise variable with the stored periodically-generated, heavy-tail noise variable, and thereby generate a multiplied wideband output signal to be transmitted as a jamming signal; and
a gate device operatively connected to receive the periodically-generated heavy-tail noise variable of the heavy-tail noise generator and configured to output a predetermined number of samples of the periodically-generated heavy-tail noise variable to the register.
6. A wireless communications jamming device according to claim 5 , wherein gate device is further configured to output the predetermined number of samples of the periodic heavy-tail noise variable based on a time period of Tp seconds.
7. A wireless communications jamming device according to claim 6 , further comprising:
a controller operatively connected to control operation of the wide band noise generator, the heavy-tail noise generator, the gate device and the register.
8. A wireless communications jamming device according to claim 1 , wherein the multiplier is configured as a real multiplier multiplying a single periodically-generated heavy-tail noise variable with single wideband noise variables from the wideband noise generator.
9. A wireless communications jamming device according to claim 1 , wherein the multiplier is configured as a complex multiplier multiplying a pair of periodically-generated, heavy-tail noise variables with pairs of wideband noise variables from the wideband noise generator.
10. A wireless communications jamming device according to claim 1 , wherein the wideband noise generator is configured to generate a Gaussian noise signal.
11. A wireless communications non-stationary heavy-tail jamming device, comprising:
a heavy-tailed noise generator for generating a periodic heavy-tailed noise signal derived from a heavy-tailed distribution that includes a plurality of repeated heavy-tailed distributed samples;
a low-pass filter configured to receive the periodic heavy-tailed noise signal so as to generate a narrowband noise signal;
a wideband noise generator for generating a wideband noise signal; and
a multiplier configured to multiply the narrowband noise signal with the wideband noise signal, and thereby generate a multiplied jamming output signal to be transmitted as a jamming signal.
12. A wireless communications jamming device according to claim 11 , further comprising:
a censoring device for censoring according to a censoring threshold value the heavy-tailed noise signal generated by the heavy-tailed noise generator.
13. A wireless communications jamming device according to claim 11 , further comprising:
a limiting device for limiting according to a limiting threshold value the heavy-tailed noise signal generated by the heavy-tailed noise generator.
14. A wireless communications jamming device according to claim 11 , wherein
the narrowband noise generator is configured for generating a pair of narrowband noise signals derived from a heavy-tailed distribution;
the wideband noise generator configured for generating a pair of wideband noise signals;
the multiplier is configured as a complex multiplier for multiplying the pair of narrowband noise signals with the pair of wideband noise signals, and thereby generate a complex multiplied jamming output.
15. A wireless communications heavy-tail non-stationary jamming device, comprising:
a narrowband noise generator for generating a narrowband noise signal derived from a heavy-tailed distribution;
a wideband noise generator for generating a wideband noise signal; and
a multiplier configured to multiply the narrowband noise signal with the wideband noise signal, and thereby generate a multiplied jamming output signal to be transmitted as a jamming signal, wherein the narrowband noise generator is configured to generate a narrowband noise signal derived from a heavy-tailed distribution of at least one of Gaussian noise, heavy-tail noise, α-stable distribution, Pareto distribution, Compound Poisson and Gaussian Scale Mixture.
16. A wireless communications jamming device according to claim 1 , wherein
the multiplier is configured to multiply a plurality of wideband noise variables with each stored and periodically-generated heavy-tail noise variable.
17. A wireless communications jamming device, comprising:
a narrowband noise generator for generating a narrowband noise signal derived from a heavy-tailed distribution;
a wideband noise generator for generating a wideband noise signal; and
a multiplier configured to multiply the narrowband noise signal with the wideband noise signal, and thereby generate a multiplied jamming output signal to be transmitted as a jamming signal, wherein
the multiplier is configured to multiply the wideband noise signal with the narrowband noise signal, and
the narrowband noise signal is fixed in amplitude for a non-zero time duration T p .