TRANSMIT-REFERENCE METHODS IN SOFTWARE DEFINED RADIO PLATFORMS FOR COMMUNICATION IN HARSH PROPAGATION ENVIRONMENTS AND SYSTEMS THEREOF

• US 20150270923A1
• Filed: 02/02/2015
• Published: 09/24/2015
• Est. Priority Date: 06/08/2009
• Status: Active Grant

• Current Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Inventors: Dowla, Farid, Nekoogar, Faranak
• Granted Patent: US 9,537,604 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03K 3/00 Circuits for generating electric pulses; Monostable, bistable or multistable circuits H03K4/00 takes precedence; for digital function generators in computers G06F1/02
• CPC Class Codes: H04B 1/0003 Software-defined radio [SDR] systems, i.e. systems wherein components typically implemented in hardware, e.g. filters or modulators/demodulators, are implented using software, e.g. by involving an AD or DA conversion stage such that at least part of the signal processing is performed in the digital domain digital baseband systems H04L25/00; digital modulation/demodulation H04L27/00; CDMA H04B1/707; TDMA H04B7/2643; image transmission H04N5/00
• CPC Class Codes: H04K 2203/00 Jamming of communication; Countermeasures
• CPC Class Codes: H04K 3/42 characterized by the control of the jamming frequency or wavelength
• CPC Class Codes: H04K 3/44 characterized by the control of the jamming waveform or modulation type
• 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: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]

Abstract

A method for adaptive Radio Frequency (RF) jamming according to one embodiment includes dynamically monitoring a RF spectrum; detecting any undesired signals in real time from the RF spectrum; and sending a directional countermeasure signal to jam the undesired signals. A method for adaptive Radio Frequency (RF) communications according to another embodiment includes transmitting a data pulse in a RF spectrum; and transmitting a reference pulse separated by a predetermined period of time from the data pulse; wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated. A method for adaptive Radio Frequency (RF) communications according to yet another embodiment includes receiving a data pulse in a RF spectrum; and receiving a reference pulse separated in time from the data pulse, wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated; and demodulating the pulses.

Claims

1. A method for adaptive Radio Frequency (RF) jamming, the method comprising:

dynamically monitoring a RF spectrum;

detecting any undesired signals in real time from the RF spectrum; and

sending a directional countermeasure signal to jam the undesired signals,

wherein the directional countermeasure signal is adaptively generated in real-time according to a bandwidth of the undesired signals, the bandwidth of the undesired signals being in a range from a narrow bandwidth to an ultra-wide bandwidth (UWB),

wherein the directional countermeasure signal is sent by a directional antenna that directs the directional countermeasure signal towards a source of the undesired signals.

2. The method of claim 1, wherein the directional countermeasure signal is narrow-band to focus on a narrow range of frequencies in the RF spectrum.

3. The method of claim 1, wherein the directional countermeasure signal is ultra-wideband to cover a very wide range of frequencies in the RF spectrum.

4. The method of claim 1, wherein the directional countermeasure signal comprises at least two of:

a narrow-band signal to focus on a narrow range of frequencies in the RF spectrum;

a wideband signal to cover a wide range of frequencies in the RF spectrum; and

an ultra-wideband signal to cover a very wide range of frequencies in the RF spectrum.

5. A Radio Frequency (RF) communications system, the system comprising:

one or more ultra-wideband (UWB) radios, each UWB radio being a software-defined radio (SDR) system comprising;

a processor configured to execute software; and

software configured to cause the SDR system to;

perform an interference modulation technique to adaptively jam at least two undesired signals simultaneously, wherein performing the interference modulation technique to adaptively jam the at least two undesired signals includes emitting one or more jamming signals towards a source of the at least two undesired signals, wherein each of the one or more jamming signals are characterized by a signal bandwidth ranging from narrow-band to ultra-wideband;

wherein the one or more UWB radios are each configured to communicate with a satellite uplink base station using wireless communications that are controlled by the SDR system thereof,

wherein the one or more UWB radios each comprise one or more interfaces for coupling to one or more endpoint devices.

6. The system of claim 5, wherein an Emergency Communications Network is used to communicate between the one or more endpoint devices and the satellite uplink base station.

7. The system of claim 5, further comprising the satellite uplink base station,

wherein the satellite uplink base station comprises:

a router;

a power supply configured to provide power to the uplink base station; and

a broadband global area network (BGAN) satellite uplink capable of maintaining a satellite uplink while in motion, wherein the BGAN satellite uplink is operatively coupled to the router.

8. The system of claim 5, wherein the software is further configured to cause the SDR system to perform Transmit-Reference (TR) modulation in real-time by adaptively changing at least two of the following parameters of the SDR system in real-time:

an operating frequency,

a pulse shape,

a delay between pulses,

a delay between symbols,

a pulse width,

a modulation scheme,

an encryption,

an error correction, and

a power output.

9. The system of claim 5, wherein the software is further configured to cause the SDR system to perform multipulse modulation.

10. The system of claim 9, wherein the one or more UWB radios are configured to use multipath receivers to enhance a signal-to-noise (SNR) ratio.

11. The system of claim 9, wherein multipulse modulation comprises:

transmitting a data pulse separated in time from a reference pulse,

wherein the data pulse is modulated with data,

wherein the reference pulse is unmodulated, and

wherein the data pulse is modulated with data based on a relative polarity of the data pulse and the reference pulse.

12. The system of claim 10, wherein the data pulse and the reference pulse are wideband pulses chosen from a group consisting of:

Gaussian, chirp, and Hermite-based.

13. The system of claim 10, wherein the one or more jamming signals comprise directional countermeasure signals.

14. The system of claim 5, wherein the one or more endpoint devices each comprise:

a commercial off the shelf (COTS) device that is configured to perform data and voice communications; and

an interface for coupling to the UWB radio to the one or more UWB radios.

15. The system of claim 5, wherein the one or more UWB radios include an omni-antenna capable of receiving UWB signals.

16. A method for adaptive Radio Frequency (RF) communications, the method comprising:

transmitting a data pulse in a RF spectrum; and

transmitting a reference pulse separated by a predetermined period of time from the data pulse;

wherein the data pulse is modulated with data,

wherein the reference pulse is unmodulated.

17. The method of claim 16, further comprising:

dynamically monitoring a RF spectrum;

detecting any undesired signals in real time from the RF spectrum; and

sending one or more directional countermeasure signals to jam the undesired signals simultaneously, wherein the one or more directional countermeasure signals are adaptively generated in real-time according to a bandwidth of the undesired signals, the bandwidth of the undesired signals being in a range from a narrow bandwidth to an ultra-wide bandwidth (UWB), wherein the one or more directional countermeasure signals are sent by a directional antenna that directs the one or more countermeasure signals towards a source of the undesired signals.

18. The method of claim 16, further comprising:

interfacing with an endpoint device;

initiating communications between a satellite uplink base station and the endpoint device across a primary communication network;

detecting a failure in the primary communications network; and

initiating communications between the satellite uplink station and the endpoint device across a backup communications network in response to detecting the failure in the primary communications network.

19. A method for adaptive Radio Frequency (RF) communications, the method comprising:

receiving a data pulse in a RF spectrum, wherein the data pulse is modulated with data;

receiving a reference pulse separated in time from the data pulse, wherein the reference pulse is unmodulated; and

demodulating the pulses.

20. The method of claim 19, further comprising:

dynamically monitoring the RF spectrum;

detecting any undesired signals in real time from the RF spectrum; and

sending a directional countermeasure signal to jam the undesired signals, wherein the directional countermeasure signal is sent by a directional antenna that directs the directional countermeasure signal towards a source of the undesired signals.