WO2016196291A1

WO2016196291A1 - High-bandwidth undersea communication

Info

Publication number: WO2016196291A1
Application number: PCT/US2016/034652
Authority: WO
Inventors: Narayana Sateesh Pillai
Original assignee: Hyfex
Priority date: 2015-05-29
Filing date: 2016-05-27
Publication date: 2016-12-08
Also published as: AU2016271619A1; EP3304640A1

Abstract

Described are methods, apparatuses, and networks for propagating a wireless signal in an electromagnetically-attenuating ionic solution, e.g., suitable for high bandwidth undersea communications. For example, the method may include transmitting a signal into the electromagnetically-attenuating ionic solution by applying a time-varying excitation field to the electromagnetically-attenuating ionic solution. The signal may correspond to the time-varying excitation field. The time-varying excitation field may include one or more of: an electrical component and a magnetic component. The method may include receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution. The signal may be wirelessly propagated in the electromagnetically-attenuating ionic solution.

Description

High-Bandwidth Undersea Communication

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/168,202 filed on May 29, 2016, which is incorporated by reference herein in its entirety.

BACKGROUND

[0002] Conventional means of undersea communication use acoustical or Very Low Frequency (VLF) electromagnetic (EM) waves or Extremely Low Frequency (ELF) electromagnetic waves. Because the speed of EM waves in a material medium depends on the permeability and permittivity of the medium, EM waves may be attenuated with increasing electrical conductivity of the medium and/or increasing frequency of the EM wave. Seawater, for example, is conductive, including ions of dissolved salts such as chloride, sodium, potassium, magnesium, calcium, sulfate, hydronium and hydroxide ions. Accordingly, low bandwidth VLF and ELF EM waves are used for long-range undersea communication with, e.g., submarines, and are low-bandwidth compared to through-air electromagnetic communication such as radio, WiFi, cellular transmissions, and the like. Acoustic waves may be transmitted underwater via pressure compression and rarefactions of, for example, sea water. Acoustic waves in air travel at about 331 m/s, and at higher speeds in sea water because of the higher bulk density of sea water. However, the distance of effective acoustic communication is limited underwater due to rapid attenuation of sound waves, reflection and refraction by thermal and density variations, background noise in the ocean, and the like.

[0003] The present application appreciates that undersea communication may be a challenging endeavor.

SUMMARY

[0004] In one embodiment, a method for propagating a wireless signal in an electromagnetically-attenuating ionic solution is provided. The method may include transmitting a signal into the electromagnetically-attenuating ionic solution by applying a time-varying excitation field to the electromagnetically-attenuating ionic solution. The signal may correspond to the time-varying excitation field. The time-varying excitation field may include one or more of: an electrical component and a magnetic component. The method may include receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution. The signal may be wirelessly propagated in the electromagnetically-attenuating ionic solution.

[0005] In another embodiment, a system for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The system may include a transmitter apparatus. The transmitter apparatus may include a signal generator. The signal generator may be operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field. The time-varying excitation field may include one or more of: an electrical component and a magnetic component. The system may include a receiver apparatus. The receiver apparatus may include a signal receiver. The signal receiver may be operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

[0006] In one embodiment, a communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The communications network may include a plurality of transmitting apparatuses and a plurality of receiving apparatuses. The plurality of transmitting apparatuses and the plurality of receiving apparatuses may be configured to be wirelessly coupled through the electromagnetically- attenuating ionic solution. Each transmitter apparatus may include a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field including one or more of: an electrical component and a magnetic component. Each receiver apparatus may include a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically- attenuating ionic solution.

[0007] In one embodiment, a communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The communications network may include a plurality of transceivers. The plurality of transceivers may be configured to be wirelessly coupled through the electromagnetically-attenuating ionic solution. Each transceiver may include a transmitter apparatus including a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field including one or more of: an electrical component and a magnetic component. Each transceiver may include a receiver apparatus including a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution. [0008] In another embodiment, a broadcast communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The broadcast communications network may include at least one transmitter apparatus and a plurality of receiver apparatuses configured together to form the broadcast network. The broadcast network may be configured to wirelessly broadcast the signal from each transmitter apparatus through the electromagnetically-attenuating ionic solution to each of the plurality of receiver apparatuses. Each transmitter apparatus may include a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field may include one or more of: an electrical component and a magnetic component. Each receiver apparatus may include a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

[0009] In one embodiment, a listening communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The listening communications network may include a plurality of transmitter apparatuses and at least one receiver apparatus. The listening network may be configured to wirelessly transmit the signal from the plurality of transmitter apparatuses through the electromagnetically-attenuating ionic solution to each receiver apparatus. Each transmitter apparatus may include a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field may include one or more of: an electrical component and a magnetic component. Each receiver apparatus may include a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying figures, which are incorporated in and constitute a part of the specification, illustrate example methods and apparatuses, and are used merely to illustrate example embodiments.

[0011] FIG. 1 is a flow diagram depicting an exemplary method for propagating a wireless signal in an electromagnetically-attenuating ionic solution. [0012] FIG. 2A is a block diagram of an exemplary system for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0013] FIG. 2B is a block diagram of an exemplary transmitter apparatus for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0014] FIG. 2C is a block diagram of an exemplary receiver apparatus for receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0015] FIG. 2D is a block diagram of an exemplary transceiver apparatus for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0016] FIG. 3 shows a block diagram of the exemplary system coupled to a platform and operatively coupled to a body of water.

[0017] FIG. 4 is a block diagram of an exemplary communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0018] FIG. 5A is a block diagram of an exemplary broadcast communications network.

[0019] FIG. 5B is a block diagram of an exemplary listening communications network.

[0020] FIG. 6 is an illustration showing an exemplary apparatus used in the Example.

[0021] FIG. 7 shows Table 700, including the raw and calculated data collected as signal frequency was varied. Values for Current 12 (mA p-p), Receive Coil (mV p-p) and Input Voltage (V) were measured on an oscilloscope. The received coil power (in mW), input mVA and transmission efficiency from input mVA were calculated.

[0022] FIG. 8 is a graph of data collected showing the received power as a function of frequency in MHz. versus different media between the coils, including seawater.

[0023] FIG. 9 is a graph of data showing the transmission efficiency between coils spaced

75 cm apart. Received power in mW is expressed as a percentage of the input mVA.

[0024] FIG. 10 is a block diagram of a receiver apparatus including a carbon electrode for receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0025] FIG. 11 is a block diagram of a transceiver apparatus for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution.

[0026] FIG. 12 is a graph of filtered receive signal amplitude measured on an oscilloscope, showing RX signal amplitude (mV p-p) versus frequency in MHz for different media at different distances, including 8 feet of high conductivity seawater, 12 feet of low-conductivity pool water, and 30 feet of low-conductivity pool water.

[0027] FIG. 13 is a graph of frequency dependence of the transmit coil power in milliwatts RMS versus frequency in MHz. [0028] FIG. 14 is a graph of RX amplitude ratio in pool water versus frequency in MHz. The amplitude ratio is shown at 30 feet/ 12 feet with different powers of 1/r, 1/r², and 1/r³ to demonstrate 1/r dependence.

[0029] FIG. 15 is a table showing received data based on a transmitted tone sent using amplitude modulation. The table shows: transmit frequency in MHz; an observation of the received signal as noisy or sinusoid-like; filtered received amplitude (mV p-p) for mean, min, max, and standard deviation; and observations of whether the sent tone was heard at the receiver.

[0030] FIG. 16 is a graph showing received signal (mV p-p) in seawater versus frequency in MHz with optimized receiver wiring.

DETAILED DESCRIPTION

[0031] In various embodiments, a method for propagating a wireless signal in an electromagnetically-attenuating ionic solution is provided. FIG. 1 is a flow diagram depicting an exemplary method 100 for propagating a wireless signal in an electromagnetically-attenuating ionic solution. Method 100 may include 102 transmitting a signal into the electromagnetically- attenuating ionic solution by applying a time-varying excitation field to the electromagnetically- attenuating ionic solution. The signal may correspond to the time-varying excitation field. The time-varying excitation field may include one or more of: an electrical component and a magnetic component. Method 100 may include 104 receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution. The signal may be wirelessly propagated in the electromagnetically-attenuating ionic solution.

[0032] In some embodiments, the signal may include one or more of an analog component and a digital component. The method may include transmitting the signal into the electromagnetically-attenuating ionic solution and receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution. The signal may be wirelessly communicated via the electromagnetically-attenuating ionic solution. The method may include receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution by one or more of: electrically detecting the signal and magnetically detecting the signal. In some embodiments, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may exclude one or more of: detecting an electromagnetic wave corresponding to the signal and detecting a mechanical acoustic wave corresponding to the signal. At least a portion of the signal may be carried in the electromagnetically-attenuating ionic solution by other than an electromagnetic wave.

[0033] In several embodiments, the electromagnetically-attenuating ionic solution may substantially attenuate an electromagnetic wave component corresponding to the signal such that receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may substantially exclude receiving the electromagnetic wave component. The signal may correspond to data encoded in the time-varying excitation field. The data may include one or more of: digital data and analog data. The method may include forming the signal by encoding data in the time-varying excitation field. The method may include forming the signal by encoding data and modulating the encoded data in the time-varying excitation field. The method may include forming the signal by encoding data and modulating the encoded data in the time- varying excitation field by one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying amplitude shift keying, and software defined radio. The method may include obtaining data encoded in the signal by one or more of: decoding at least a portion of the signal and demodulating at least a portion of the signal, e.g., using amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio.

[0034] In various embodiments, the method may include forming the signal by encoding data in the time-varying excitation field. The method may include obtaining data encoded in the signal by one or more of: decoding at least a portion of the signal and demodulating at least a portion of the signal. The encoded modulated data may be wirelessly communicated through the electromagnetically-attenuating ionic solution. Receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may include detecting from the electromagnetically-attenuating ionic solution at least a portion of one or more of: the time- varying excitation field and an excitation in the electromagnetically-attenuating ionic solution corresponding to the time-varying excitation field.

[0035] In various embodiments, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may include operatively coupling one or more signal detectors to the electromagnetically-attenuating ionic solution. The one or more signal detectors may be operatively coupled to the electromagnetically-attenuating ionic solution. For example, the one or more signal detectors may be one of: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution. Transmitting the signal into the electromagnetically-attenuating ionic solution may include operatively coupling one or more signal emitters to the electromagnetically-attenuating ionic solution. The one or more signal emitters may be operatively coupled to the electromagnetically-attenuating ionic solution. For example, the one or more signal emitters may be one of: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically- attenuating ionic solution. Receiving the signal may include detecting one or more of: an electrical signature corresponding to the time-varying excitation field and a magnetic signature corresponding to the time-varying excitation field.

[0036] In some embodiments, transmitting the signal into the electromagnetically-attenuating ionic solution may include creating in the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field. Receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may include detecting from the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field. The method may include transmitting the signal and receiving at least a portion of the signal to provide wireless communication via the electromagnetically attenuating ionic solution that is one or more of: simplex, half duplex, full duplex, time division duplex, and frequency division duplex.

[0037] In several embodiments, applying the time-varying excitation field to the electromagnetically-attenuating ionic solution may include driving a transmitter via buffered amplification. The transmitter may be driven by the buffered amplification at one or more of: greater than about unity gain, about unity gain, or less than about unity gain, e.g., greater than about unity gain. The buffered amplification may be switched or unswitched.

[0038] In various embodiments, the method may include generating the signal and subjecting the signal to the buffered amplification effective to drive the transmitter. The signal may include a carrier component and a modulated signal component. The method may include one or more of: generating the carrier component, generating the modulated component, and modulating the carrier component with the modulated component to generate the signal. Receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution may include collecting the at least a portion of the signal in a receiver. The signal may be analog or digital. The signal collected by the receiver may be demodulated using one or more of: amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio. In some embodiments, the entire receiver may be a software defined radio. [0039] In some embodiments, the portion of the signal received from the electromagnetically-attenuating ionic solution may include a common mode component. The method may include collecting a common mode ground reference. The method may include rejecting at least a portion of the common mode component by difference using the common mode ground reference to provide a difference mode signal.

[0040] In several embodiments, the method may include wirelessly propagating the signal in the electromagnetically-attenuating ionic solution over a distance in meters of at least about one or more of: 1, 5, 10, 15, 20, 25, 50, 75, 100, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, 7500, and 10,000. The method may include wirelessly propagating the signal in the electromagnetically-attenuating ionic solution at a frequency range in MHz of about one or more of: 1 to 100, 20 to 80, 20 to 65, 30 to 50, 35 to 45, 35 to 40, and 50 to 60. The electromagnetically-attenuating ionic solution may include one or more of: seawater; brine; fracking fluid; surface water; ground water; waste water; treated water, that is, water for recreation or commercial processing that may be treated for algae, bacteria, parasites, viruses, and the like, e.g., chlorinated, treated with silver or copper ions, and the like, such as pool water, spa water, cooling system water, aquatic feature water such as amusement rides or fountains, and the like; tap water; a biological fluid; a bioreactor fluid; an industrial process fluid; an ionic solvent; and the like. The electromagnetically-attenuating ionic solution may include a conductivity of in Siemens/meter at 25 °C of at least one or more of about: 0.001, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, and 25.

[0041] In some embodiments, the signal may be transmitted into a body of water from or received from a body of water by one of: a surface vessel, a submarine, a drone, an unmanned submersible vehicle, a buoy, a sensor, an amphibious airplane, a weapon, a relay station, a navigational beacon, a distress beacon, a flight data recorder (e.g., flight data recorders commonly referred to as a "black box"), a voyage data recorder, a scientific instrument, a personal diving device, a personal floatation device, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment (e.g., an oil drilling platform), a monitoring station, an aircraft configured to operatively couple at least one of the transmitter and the receiver to the body of water while airborne (e.g., via a probe lowered via cable to the body of water), oil or natural gas infrastructure (e.g., an undersea pipeline), transportation infrastructure, undersea cable communications infrastructure, a fixed marine installation, a fixed shore installation, and the like.

[0042] In several embodiments, the method may include wirelessly propagating the signal in the electromagnetically-attenuating ionic solution with dependency of signal variation with distance r of about 1/r. For example, the method may include wirelessly propagating the signal in the electromagnetically-attenuating ionic solution such that the signal is received with a signal variation with distance r of about 1/r. The method may also include conducting the transmitting the signal or receiving at least a portion of the signal using a carbon electrode or similar solid conductor protected from corrosion and in contact with the electromagnetically-attenuating ionic solution.

[0043] In various embodiments, a system for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. FIG. 2A is a block diagram of an exemplary system 200A for transmitting or receiving a signal propagated in an electromagnetically-attenuating ionic solution. System 200A may include a transmitter apparatus 202. Transmitter apparatus 202 may include a signal generator 204. Signal generator 204 may be operatively coupled to a transmitter 206 effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution 208. The time-varying excitation field carrying may carry a corresponding signal. Signal generator 204 and transmitter 206 may be configured together to create the time-varying excitation field. The time-varying excitation field may include one or more of: an electrical component and a magnetic component. System 200A may include a receiver apparatus 210. Receiver apparatus 210 may include a signal receiver 212. Signal receiver 212 may be operatively coupled to a detector 214 effective to receive at least a portion of the signal from electromagnetically-attenuating ionic solution 208.

[0044] In some embodiments, system 200A may include one of transmitter apparatus 202 and receiver apparatus 210. For example, transmitter apparatus 202 and receiver apparatus 210 may be configured together to form a transceiver. System 200A may be configured for one or more of: digital operation and analog operation.

[0045] In several embodiments, one or more of transmitter 206 and signal receiver 212 may be configured effective to respectively transmit and receive the time-varying excitation field by being operatively coupled to the electromagnetically-attenuating ionic solution, e.g., under one or more conditions of: being in contact with the electromagnetically-attenuating ionic solution, being immersed in the electromagnetically-attenuating ionic solution, and being separated from the electromagnetically-attenuating ionic solution, e.g., by an air gap.

[0046] In various embodiments, signal generator 204 may include one or more of: a local oscillator, a digital signal generator, an analog signal generator, an audio signal generator, a photodiode, and a charge coupled device. System 200A may include a buffer driver (not shown) operatively coupled to signal generator 204 and transmitter 206. The buffer driver may be configured to operate greater than about unity gain, about unity gain, or less than about unity gain. The buffer driver may be switched or unswitched.

[0047] In some embodiments, one or more of transmitter 206 and signal receiver 212 each may independently include one or more of: a conducting coil and an electrode structure. One or more of transmitter 206 and signal receiver 212 may each independently include a conducting coil (not shown). One or more of transmitter 206 and signal receiver 212 may each independently include a carbon electrode, e.g., carbon electrode 1004 as demonstrated in receiver 1000 in FIG. 10. The conducting coil may include a number of turns of about one or more of: 1, 2, 3, 4, 5, 7, 9, 1 1, 13, 15, 20, 25, 30, 35, 40, 50, 100, 200, 250, 500, 750, 1000, 2000, 2500, 5000, 7500, 10,000, and the like. The conducting coil may be characterized by an average diameter in centimeters of about, or at least about, one of: 1, 2, 3, 4, 5, 7, 9, 1 1, 13, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 500, 750, 1000, 1250, 1500, 1750, 2000, and the like. For example, a seagoing vessel, such as a submarine, may have a hull diameter of about 13 meters, and the conducting coil may be configured along the hull to have a diameter of about 13 meters. In some embodiments, the conducting coil may be arranged in a vessel in an orientation to have a diameter larger than the hull diameter, for example, by coiling about the hull in a plane that is a diagonal cross section to the hull's cross section perpendicular to the normal direction of hull travel, that is, the plane of the coil may be other than perpendicular to the major axis of the hull. One or more of transmitter 206 and signal receiver 212 each may include one or more of: a corrosion-resistant conductor, a corrosion-resistant coating, a carbon electrode, and a water resistant coating. The corrosion-resistant conductor, the corrosion- resistant coating, the carbon electrode, and the water-resistant coating may be at least partly resistant to the electromagnetically-attenuating ionic solution. The corrosion resistant coating and the water-resistant coating each may be permeable to the signal.

[0048] In several embodiments, signal receiver 212 may be configured effective to receive the time-varying excitation field by being operatively coupled to the electromagnetically- attenuating ionic solution, for example, one or more of being: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution.

[0049] In various embodiments, receiver apparatus 210 may include a high frequency amplifier 216, that may be, e.g., differential or single-ended. Signal receiver 212 may be operatively coupled to one or more inputs of high frequency amplifier 216. Detector 214 may be operatively coupled to one or more outputs of high frequency amplifier 216. Receiver apparatus 210 may include a ground coil (not shown) operatively coupled to the one or more inputs of high frequency amplifier 216. High frequency amplifier 216 may be configured to detect a common mode ground reference in the ground coil. High frequency amplifier 216 may be configured to reject the common mode ground reference from a signal received at signal receiver 212. Signal receiver 212 may include a coil (not shown) having a first number of turns compared to a second number of turns of the ground coil. The first number of turns may be, compared to the second number of turns, one of: greater, lesser, or the same.

[0050] In some embodiments, receiver apparatus 210 may include a demodulator (not shown) configured to demodulate a received signal that was modulated at the transmitter by one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying amplitude shift keying, and software defined radio. That is, the demodulator may function by one or more of: amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio. In some embodiments, the entire receiver apparatus may consist of a software defined radio. As used herein, references to "modulation" and "modulator" and the like may be understood to encompass modulation and demodulation where appropriate, for example, as part of a transceiver.

[0051] In various embodiments, transmitter apparatus 202 may include a modulator (not shown) operatively coupled to modulate the signal using one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying, amplitude shift keying, and software defined radio. In some embodiments, the entire transmitter apparatus may be a software defined radio. In some embodiments, the receiver apparatus 210 may include a demodulator operatively coupled to demodulate the received signal that was modulated using one or more of: amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio. . In some embodiments, the entire receiver apparatus may consist of a software defined radio.

[0052] Receiver apparatus 210 may include an output module 218 operatively coupled to signal receiver 212. Output module 218 may be configured to convert the signal to one or more of: a visible signal and an audible signal.

[0053] In several embodiments, transmitter apparatus 202 may be configured to apply the time-varying excitation field to the electromagnetically-attenuating ionic solution to wirelessly propagate the signal into the electromagnetically-attenuating ionic solution. Receiver apparatus 210 may be configured to wirelessly receive at least a portion of the signal from the electromagnetically-attenuating ionic solution. The signal may be wirelessly propagated in the electromagnetically-attenuating ionic solution. Receiver apparatus 210 may be configured to receive the signal from the electromagnetically-attenuating ionic solution via one or more of: electrically detecting the signal and magnetically detecting the signal. Receiver apparatus 210 may be configured to receive the signal from the electromagnetically-attenuating ionic solution excluding one or more of: detecting an electromagnetic wave corresponding to the signal and detecting a mechanical acoustic wave corresponding to the signal. System 200A may be configured such that at least a portion of the signal is carried in the electromagnetically- attenuating ionic solution by other than an electromagnetic wave. System 200A may be configured to propagate the signal in the electromagnetically-attenuating ionic solution under conditions such that the electromagnetically-attenuating ionic solution substantially attenuates an electromagnetic wave component corresponding to the signal. The signal may correspond to data encoded in the time-varying excitation field. The data may include one or more of: digital data, analog data, a video signal, and an audio signal. Transmitter apparatus 202 may be configured to form the signal to be transmitted by encoding data in the time-varying excitation field. Receiver apparatus 210 may be configured to receive from the electromagnetically- attenuating ionic solution at least a portion of one or more of: the time-varying excitation field and an excitation in the electromagnetically-attenuating ionic solution corresponding to the time- varying excitation field. Receiver apparatus 210 may be configured to detect one or more of: an electrical signature corresponding to the time-varying excitation field and a magnetic signature corresponding to the time-varying excitation field. Transmitter apparatus 202 may be configured to apply the time-varying excitation field to create in the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

[0054] In various embodiments, receiver apparatus 210 may be configured to detect from the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field. Receiver apparatus 210 and transmitter apparatus 202 may be configured to provide wireless communication via the electromagnetically attenuating ionic solution that is one or more of: simplex, half duplex, full duplex, time division duplex, and frequency division duplex.

[0055] In some embodiments, system 200A may be configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution over a distance in meters of at least about one or more of: 0.1, 0.25, 0.5, 0.75, 1, 5, 10, 15, 20, 25, 50, 75, 100, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, 7500, and 10,000. System 200A may be configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution at a frequency range in MHz of about one or more of: 1 to 100, 20 to 80, 20 to 65, 30 to 50, 35 to 45, 35 to 40, and 50 to 60.

[0056] FIG. 2B is a block diagram of an exemplary transmitter apparatus 200B for transmitting a signal propagated in an electromagnetically-attenuating ionic solution. A signal source 250 may provide a signal to transmitter apparatus 200B at encoder module 252. The resulting encoded signal may be modulated at modulator 254, e.g., making use of local oscillator 256 to provide a modulation wave. The resulting modulated signal may be passed through a bandpass filter 258 to remove undesired frequencies, and passed through a buffer driver 260 before being applied to coil 262. Coil 262 may be placed operatively coupled to the electromagnetically-attenuating ionic solution, e.g., in contact with, or at a separation from the electromagnetically-attenuating ionic solution, e.g., seawater.

[0057] FIG. 2C is a block diagram of an exemplary receiver apparatus 200C for receiving a signal propagated in an electromagnetically-attenuating ionic solution. Exemplary receiver apparatus 200C may include, for example, a coil such as coil 262, which may be operatively coupled, e.g., placed in, in contact with, or at a separation from the electromagnetically- attenuating ionic solution, e.g., seawater. In receiver apparatus 200, coil 262 may be operatively coupled to a high frequency amplifier 270, that may be, e.g., differential or single ended. High frequency amplifier 270 may also be coupled with a second coil 262', which may also be operatively coupled, e.g., placed in, in contact with, or at a separation from the electromagnetically-attenuating ionic solution. High frequency amplifier 270 may be configured to use coil 262' as a ground coil capable of rejecting ground loop interference. High frequency amplifier 270 may also be operatively coupled to a bandpass filter 272 to reject undesired frequencies. Bandpass filter 272 may be operatively coupled to demodulator/mixer 274, optionally via an amplifier 271.

[0058] In various embodiments, demodulator/mixer 274 may be configured to demodulate the signal, for example, optionally in conjunction with a local oscillator such as local oscillator 256'. For example, demodulator/mixer 274 may be configured in conjunction with local oscillator 256', for example, to translate the signal to the intermediate frequency (IF) carrier signal. The IF carrier signal may be amplified, detected, and/or decoded. In some embodiments, selectivity may thereby be increased for received apparatus 200. In the absence of generating the IF carrier signal, demodulator/mixer 274 may be configured in conjunction with local oscillator 256' to demodulate the received signal. In another embodiment, the received signal may be directly converted and decoded without local oscillator 256'.

[0059] Demodulator/mixer 274 may be coupled to channel and signal decoder/demodulator 276, optionally via an amplifier 271. The decoded/demodulated signal may be output from channel and signal decoder/demodulator 276, optionally via amplifier 271. The signal may be passed to a signal output device 278, such as a speaker or display.

[0060] FIG. 2D is a block diagram of an exemplary transceiver apparatus 200D for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution. Exemplary transceiver apparatus 200D is similar to exemplary transmitter apparatus 200B and exemplary receiver apparatus 200C, with the following differences. Exemplary transmitter apparatus 200B and exemplary receiver apparatus 200C may be alternately coupled to coil 262 through transmit/receive switch 280. Accordingly, coil 262 may alternately be used to transmit or to receive the signal. Other transceiver embodiments may employ different coils for each of the transmitter and receiver apparatuses (not shown). Some embodiments may use a carbon electrode or a corrosion-resistant electrical conductor directly in contact with the electromagnetically-attenuating ionic solution for the receiver.

[0061] In several embodiments, at least one of transmitter apparatus 202 and receiver apparatus 210 may be coupled to a platform configured to be operatively coupled to a body of water. FIG. 3 shows a block diagram of system 200 coupled to an exemplary platform 302 and operatively coupled to a body of water 304. Platform 302 may include one of: a surface vessel, a submarine, a drone, an unmanned submersible vehicle, a buoy, a sensor, an amphibious airplane, a weapon, a relay station, a navigational beacon, a distress beacon, a flight data recorder, a voyage data recorder, a scientific instrument, a personal diving device, a personal floatation device, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment (e.g., an oil drilling platform), a monitoring station, an aircraft configured to operatively couple at least at least one of the transceiver and the receiver to the body of water while airborne (e.g., via a probe lowered to the body of water), oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, a fixed marine installation, a fixed shore installation, and the like.

[0062] References to the transmitter apparatus and the receiver apparatus herein, e.g., in the following description of the various communications networks, may be understood as describing each such transmitter apparatus and receiver apparatus individually, or together in each described transceiver. References to each described transceiver in the following may be understood as describing, in relevant part, each such transmitter apparatus and receiver apparatus individually, or together in each described transceiver.

[0063] In various embodiments, a communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. The communications network may include a plurality of transmitting and receiving apparatuses. In various embodiments, the plurality of transmitting and receiving apparatuses may be configured as a broadcast network as described herein, e.g., including at least a plurality of transmitting apparatuses and a plurality of receiving apparatuses, or a plurality of transceivers each comprising one transmitting apparatus and one receiving apparatus, combinations thereof, and the like. The plurality of transmitting and receiving apparatuses may include at least one transmitting apparatus and at least two receiving apparatuses, e.g., configured as a broadcast network as described herein. The plurality of transmitting and receiving apparatuses may include at least one receiving apparatus and at least two transmitting apparatuses, e.g., configured as a listening network as described herein.

[0064] The plurality of plurality of transmitting and receiving apparatuses may be configured to be wirelessly coupled through the electromagnetically-attenuating ionic solution. Each transmitter apparatus may include a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field including one or more of: an electrical component and a magnetic component. Each receiver apparatus may include a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

[0065] In several embodiments, the communications network may include a plurality of transceivers. The plurality of transceivers may be configured to be wirelessly coupled through the electromagnetically-attenuating ionic solution. Each transceiver may include at least one said transmitter apparatus including a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field including one or more of: an electrical component and a magnetic component. Each transceiver may include at least one said receiver apparatus including a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution. [0066] FIG. 4 is a block diagram of an exemplary communications network 400 for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution. Communications network 400 may include a plurality of transceivers 402. Plurality of transceivers 402 may be configured to be wirelessly coupled through the electromagnetically- attenuating ionic solution. Each transceiver 402 may include, e.g., transmitter apparatus 202 including a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field including one or more of: an electrical component and a magnetic component. Each transceiver 402 may include, e.g., receiver apparatus 210 including a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

[0067] In several embodiments, each transceiver 402 may include at least one modulator operatively coupled to encode and/or decode the signal. For example, the signal may be encoded using one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying, amplitude shift keying, and software defined radio. The signal may be decoded using one or more of: amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio. In some embodiments, the receiver portion of the transceiver, the receiver portion of the transceiver, or the entire transceiver may be a software defined radio.

[0068] In some embodiments, communications network 400 may include any of the features or aspects described herein for the method or for system 200. For example, communications network 400 may be configured for one or more of: digital operation and analog operation. Each transceiver 402 may be configured effective to apply the time-varying excitation field operatively coupled to the electromagnetically-attenuating ionic solution under one or more conditions, e.g., including being one of: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution. For example, communications network 400 may be configured to operate with the electromagnetically-attenuating ionic solution including one or more of: seawater; brine; fracking fluid; surface water; ground water; waste water; treated water, that is, water for recreation or commercial processing that may be treated for algae, bacteria, parasites, viruses, and the like, e.g., chlorinated, treated with silver or copper ions, and the like, such as pool water, spa water, cooling system water, aquatic feature water such as amusement rides or fountains, and the like; tap water; a biological fluid; a bioreactor fluid; an industrial process fluid; an ionic solvent; and the like. The electromagnetically- attenuating ionic solution may include a conductivity of in Siemens/meter at 25 °C of at least one or more of about: 0.001, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, and 25.

[0069] In several embodiments, plurality of transceivers 402 may be configured to be distributed among and communicate through a body of water between a plurality of platforms configured to be operatively coupled to the body of water. The plurality of platforms may include one or more: surface vessels, submarines, drones, unmanned submersible vehicles, buoys, sensors, amphibious airplanes, weapons, relay stations, navigational beacons, distress beacons, flight data recorders, voyage data recorders, scientific instruments, personal diving devices, personal floatation devices, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment (e.g., an oil drilling platform), monitoring stations, aircraft configured to operatively couple at least one said transceiver to the seawater while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, fixed marine installations, fixed shore installations, and the like.

[0070] In various embodiments, a communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution is provided. FIGs. 5A and 5B are block diagrams of an exemplary broadcast communications network 500A and an exemplary listening communications network 500B, respectively. Broadcast communications network 500 may include at least one transmitter apparatus 502A and a plurality of receiver apparatuses 504A configured together as a broadcast network 500A. Broadcast network 500A may be configured to wirelessly broadcast the signal from each transmitter apparatus 502A through the electromagnetically-attenuating ionic solution to each of plurality of receiver apparatuses 504A. Alternatively, listening communications network 500B may include a plurality of transmitter apparatuses 502B and at least one receiver apparatus 504A. Listening network 500B may be configured to wirelessly transmit the signal from the plurality of transmitter apparatuses 502B through the electromagnetically-attenuating ionic solution to each receiver apparatus 504B. In broadcast communications network 500A and listening communications network 500B, each transmitter apparatus 502A, 502B may include a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution. The time-varying excitation field may carry a corresponding signal. The signal generator and the transmitter may be configured together to create the time-varying excitation field may include one or more of: an electrical component and a magnetic component. In broadcast communications network 500A and listening communications network 500B, each receiver apparatus 504A, 504B may include a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

[0071] In several embodiments, communications network 500A, 500B may include any of the features described herein for the method or for system 200 or communications network 400. For example, each transmitter apparatus 502A, 502B and each receiver apparatus 504A, 504B may be configured to be distributed among and communicate through a body of water between a plurality of platforms configured to be operatively coupled to the body of water. The plurality of platforms may include one or more: surface vessels, submarines, drones, unmanned submersible vehicles, buoys, sensors, amphibious airplanes, weapons, relay stations, navigational beacons, distress beacons, flight data recorders, voyage data recorders, scientific instruments, personal diving devices, personal floatation devices, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment (e.g., an oil drilling platform), monitoring stations, aircraft configured to operatively couple at least one said transmitter to the seawater while airborne (e.g., via a probe lowered to the body of water by a cable), oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, fixed marine installations, fixed shore installations, and the like.

[0072] FIG. 10 is a block diagram of a receiver apparatus 1000 for receiving a signal propagated in an electromagnetically-attenuating ionic solution, including a waterproof enclosure 1002, and a carbon electrode 1004 that extends from the inside to the outside of waterproof housing 1002 through a waterproof seal 1006. Carbon electrode 1004 may be operatively coupled, e.g., placed in, in contact with, or at a separation from the electromagnetically-attenuating ionic solution, e.g., seawater. Carbon electrode 1004 may be operatively coupled inside waterproof enclosure 1002 to a high frequency bandpass filter 1008, e.g., to reject undesired frequencies, a high frequency amplifier 1010, a demodulator 1012, a low pass filter 1014, e.g., to reject undesired frequencies, a signal amplifier 1016, and a receiver signal transducer 1018.

[0073] FIG. 11 is a block diagram of an exemplary transceiver 1100 for transmitting and receiving signals propagated in an electromagnetically-attenuating ionic solution. For transmission, a signal source 1110 may provide a signal to transceiver 1100 at signal and channel encoder module 1112. The resulting encoded signal may be modulated at modulator 1114, e.g., making use of local oscillator 1116 to provide a modulation wave. The resulting modulated signal may be passed through a bandpass filter 1118 to remove undesired frequencies, and passed through a buffer driver 1120, which may be operatively coupled via transmit/receive switch 1122 to transmit coil 1124, which may be operatively coupled, e.g., placed in, in contact with, or at a separation from the electromagnetically-attenuating ionic solution, e.g., seawater.

[0074] Transmit/receive switch 1122 may also be coupled to receiver apparatus 1000 and carbon electrode 1004, which may be operatively coupled, e.g., placed in, in contact with, or at a separation from the electromagnetically-attenuating ionic solution, e.g., seawater. The signal from receiver apparatus 1000 and carbon electrode 1004 may be coupled through transmit/receive switch 1122 to a bandpass filter 1130 to reject undesired frequencies. The signal may be passed to a demodulator/mixer 1132, which may be coupled to a local oscillator 1134. The demodulated signal may be passed to channel and signal decoder 1136. The resulting received signal 1138 may be passed to an audio, visual, or other output, or passed to a further communications processing (not shown). Optional amplifiers 1126 may be placed at various points, e.g., between bandpass filter 1130 and demodulator/mixer 1132, between demodulator/mixer 1132 and channel and signal decoder 1136, after channel and signal decoder 1136, and the like.

EXAMPLES

EXAMPLE 1

[0075] FIG. 6 is a schematic of an example apparatus 600 used in testing. Example apparatus 600 was configured with a power source 602, a first 50 ohm resistor 604, a second 50 ohm resistor 606, a 13 turn transmit coil 608 (average diameter of 9 cm), a 15 turn receive coil 610 (average diameter of 9 cm), and a 200 MHz oscilloscope 612. The coils were separated by a distance of 75 cm in seawater 614 for this example. The specific number of turns was chosen for this example, and may vary in other examples; e.g., the number of turns and the diameters of the transmit and receive coils may be the same or different in further examples. The transmit and receive coils shown in this embodiment are not required, and may be, in other examples, an electrode structure (such as the carbon electrode 1004 demonstrated in receiver 1000 of FIG. 10), antenna, or any other means of exciting the ions in sea water. Current was measured at transmit coil 608 and voltage was measured for receive coil 610 at second 50 ohm resistor 606. In this example, transmit coil 608 was connected directly to a signal generator (not shown). The signal generator can be an amplifier that provides modulated carrier signals for communicating data or audio. [0076] An experiment was carried out by applying signal from a signal generator to transmit coil 608 and measuring the voltage at receive coil 610 across second 50 ohm resistor 606. The presence and value of the resistor is merely for the present example, and may be changed or omitted in other examples.

[0077] The current through the transmit coils was measured in mA (peak to peak) with a 200 MHz current probe connected to a 200 MHz oscilloscope 612. Voltage across transmit coil 608 was measured in volts (peak to peak) using 200 MHz oscilloscope 612. The voltage at receive coil 610 across second 50 ohm resistor 606 was measured in mV (peak to peak) with a 200 MHz oscilloscope 612. The received power in mW was calculated as (1000/50)* (0.707* [receiver coil voltage]/2000)². The volt-amp (without any power factor information) was calculated in mVA by multiplying (0.707/2) times voltage across transmit coil 608 by (0.707/2) times current in mA flowing through transmit coil 608.

[0078] The raw observed data and calculated data are shown in Table 700 in FIG. 7. Measurement of the received power is shown in graph 800 in FIG. 8 as a function of the signal frequency at the transmit coil. The efficiency of transmission (received signal power expressed as a percentage of the transmitted mVA was also measured as a function of the frequency and is shown in graph 900 in FIG. 9. FIGS. 8 and 9 demonstrate transmission of a high frequency power signal between transmit coil 608 and receive coil 610. This is not electromagnetic propagation as it is well-known that EM signal is significantly attenuated over this distance in sea water.

[0079] Further perusal of the data in Table 700 in FIG. 7 shows that at a signal frequency between 13.5MHz to 19MHz, there is little to no transmission, although the input power was substantive. Application of a 5 pulse sinusoidal burst at these frequencies showed that the amplitude of successive current pulses increased with time, indicating the possibility of a resonant condition. In the case of transmission, a similar increase in amplitude of successive pulses was observed for the transmitted pulse indicating the possibility of a resonance in the transmission.

EXAMPLE 2

[0080] A 12 feet diameter above ground pool was filled with tap water and commercially available artificial sea salt was added to increase electrical conductivity to be about 40mS/cm, a value characteristic of seawater. The depth of this artificial seawater across the pool was measured to vary from 13.5 inches at one end to 14.5 inches at the diametrically opposite end. Transmit and receive setups were then tested, modified, retested multiple times until repeatable results were obtained, as follows. Both a receive electrode (RX) and a transmit coil (TX)were fully immersed in the artificial seawater to a depth of about 6 inches below the water surface. The signals to the transmit buffer driving the transmit coil were obtained from a signal generator having controllable frequency, amplitude and modulation. All components of the apparatus were arranged as for exemplary transceiver 1100 as shown in FIG. 11 and described herein.

[0081] The receive electrode included a carbon electrode which crossed the boundary of the waterproof receiver housing so that part of the carbon electrode was placed in direct contact with seawater. See the block diagram of receiver apparatus 1000 in FIG. 10 and the description thereof herein. The remainder of the carbon electrode was sealed within a water proofed, dry area that contained the receiver electronics. The portion of the carbon electrode in the dry area was attached by a conducting wire to a commercially available bandpass filter BPF-C45+ (Mini- Circuits, Brooklyn, NY) having a passband from 30MHz to 70MHz. The signal output from the bandpass filter was observed on an oscilloscope and was further amplified and demodulated to listen for a transmitted audio tone.

[0082] Both RX electrode and the TX coil were placed about 6 inches below the surface of the seawater (or pool water, in comparative examples) and the RX electrode was placed roughly 8.5 feet away from the TX coil. Tests were carried out to obtain the signal at the receive electrode as a function of frequency. By observing the received signals directly on an oscilloscope, it was observed that there was a frequency dependent transmission and reception through the seawater. Similar tests were also carried out in a nearby swimming pool with the receiver placed 12 feet and 30 feet away from the transmit coil. A similar frequency dependence of the RX signal was noticed at the swimming pool. The electrical conductivity of the swimming pool water was noted to be about 2.95mS/cm, which is less by more than an order of magnitude from the electrical conductivity of seawater. FIG. 12 is a graph of the filtered receive signal amplitude measured on an oscilloscope, showing RX signal amplitude (mV p-p) versus frequency in MHz for different media at different distances, including 8.5 feet of high conductivity seawater (SW), 12 feet of low-conductivity pool water, and 30 feet of low- conductivity pool water.

[0083] A high frequency differential probe and high frequency hall effect current sensor were used to measure amplitude of voltage and current in the TX coil to determine whether the variation seen in the RX amplitude was related to the medium (seawater) or an unrelated variation in the transmit power or amplitude. Results of the measurement are provided in FIG. 13, which graphs the frequency dependence of the transmit coil power in milliwatts RMS versus frequency in MHz. FIG. 13 shows that there is a frequency dependence, or resonance, as measured by the voltage across and the current flowing through the TX coil. This resonant frequency did not vary even though the reactive DC blocking capacitor connected to the TX coil was varied by a factor of 2 from lOOOpF to 2000pF. This result is consistent with the resonance being due to the medium in which the coil is immersed. The output of the signal generator, which is the input to the signal transistor buffer drive for the TX coil, was also measured to ensure that the signal generator did not cause the voltage variation. Measurements show that the amplitude of the signal generator for a fixed setting of 2.5 V p-p did not vary more than ±20% in the frequency range from 20MHz to 60MHz. The TX voltage varied by a factor of 7 and the TX coil current varied by nearly a factor of 12 in this range. This indicates that the driving signal generator did not cause the frequency dependence of the TX coil voltage and current, and therefore the power.

[0084] FIG. 14 is a graph of RX amplitude ratio in pool water versus frequency in MHz. The amplitude ratio is shown at 30 feet/ 12 feet with different powers of 1/r, 1/r², and 1/r³ to demonstrate 1/r dependence. The 30 foot pool data was divided by the 12 foot pool data, and scaled by dividing by 0.4 (12/30), for the 1/r plot; by 0.16 ((12/30)²), for the 1/r² plot; and by 0.064 ((12/30)³), for the 1/r³ plot. When the RX signal was low, the received signal was mainly noise, which would be independent of distance. This means for high frequency or low frequency, when the RX amplitude is low, the plot would correspond to 1/r or 1/r² or 1/r³, which it does for 20MHz; the data asymptotically tends towards that number for high frequency. When the RX signal was very large, the plot should be close to 1. This means at the frequency where RX signal has a maximum response, the plot should be very close to 1, but somewhat less than 1 because of the noise. The maximum RX signal occurred at a frequency between 38MHz and 39MHz. At both frequencies, the RX signal at 12 ft was very large, greater than 200m V p-p, and therefore much larger than the noise at both frequencies. The maximum 30 ft RX signal had sharp peak amplitude of 79mV p-p at 38MHz. The 1/r plot comes closest to 1 at this frequency with 0.944. The 1/r² plot at this point is 2.36, which is too high. This would indicate that the RX amplitude varies with distance as 1/r in the pool water, and possibly the seawater also.

[0085] The variation with 1/r is an extraordinarily surprising and unexpected observation. Moreover, the variation with about 1/r is a significant advantage over far field electromagnetic wave propagation in air, which varies substantially, especially near ground, due the presence of buildings, vegetation, geographical features, and the like. The theoretical variation for free space is 1/r². In practice, the power of r is higher than 2 due to environmental variations, obstacles and other factors, and may go as high as 4. A factor of 1/r⁴ is normally assumed in the practice of engineering cellular phone radio frequency propagation. [0086] The above measurements were repeated with more optimized wiring at the receiver. The receiver signal amplitude was measured and tabulated along with the frequencies at which amplitude modulated lKHz tones were heard. FIG. 16 is a table showing the received data based on a transmitted tone sent using amplitude modulation with the optimized wiring. The table shows: transmit frequency in MHz; an observation of the received signal as noisy or sinusoid-like; filtered received amplitude (mV p-p) for mean, min, max, and standard deviation; and observations of whether the sent tone was heard at the receiver.

[0087] FIG. 16 is a graph showing mean received signal amplitude (mV p-p) in seawater versus transmit frequency in MHz with the optimized receiver wiring. The received signal was measured directly on an oscilloscope with only a filter in between the carbon electrode and the oscilloscope input. There was no amplification of the signal when read on an oscilloscope. That is, the filtered raw signal was received at the carbon electrode. For the purpose of this data, oscilloscope measurement was performed simultaneously with the audible tone detection on another carbon electrode in contact with the seawater in the same receiver enclosure. The audible tone was detected by listening to a speaker driven by a class D amplifier with an audio gain of 2. The amplifier input was the output of an active audio filter (with an audio gain of 1.414) and amplitude modulation (AM) detector. The RF high frequency signal out of the carbon electrode was boosted by a gain of 20 before going into the AM detector. The lKHz tone was boosted further by a gain of 2.828 after the AM detection by the active filter and class D amplifier. The signal to noise ratio of the electrical signal seen at the oscilloscope for 39MHz is calculated to be about 8.7 with systematic noise in the filter band of 27mV p-p and 24mV p-p of maximum random noise.

[0088] To the extent that the term "includes" or "including" is used in the specification or the claims, it is intended to be inclusive in a manner similar to the term "comprising" as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term "or" is employed (e.g., A or B) it is intended to mean "A or B or both." When the applicants intend to indicate "only A or B but not both" then the term "only A or B but not both" will be employed. Thus, use of the term "or" herein is the inclusive, and not the exclusive use. See Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms "in" or "into" are used in the specification or the claims, it is intended to additionally mean "on" or "onto." To the extent that the term "selectively" is used in the specification or the claims, it is intended to refer to a condition of a component wherein a user of the apparatus may activate or deactivate the feature or function of the component as is necessary or desired in use of the apparatus. To the extent that the terms "operatively coupled" or "operatively connected" are used in the specification or the claims, it is intended to mean that the identified components are connected in a way to perform a designated function. To the extent that the term "substantially" is used in the specification or the claims, it is intended to mean that the identified components have the relation or qualities indicated with degree of error as would be acceptable in the subject industry.

[0089] As used in the specification and the claims, the singular forms "a," "an," and "the" include the plural unless the singular is expressly specified. For example, reference to "a compound" may include a mixture of two or more compounds, as well as a single compound.

[0090] As used herein, the term "about" in conjunction with a number is intended to include ± 10% of the number. In other words, "about 10" may mean from 9 to 11.

[0091] As used herein, the terms "optional" and "optionally" mean that the subsequently described circumstance may or may not occur, so that the description includes instances where the circumstance occurs and instances where it does not.

[0092] As stated above, while the present application has been illustrated by the description of embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art, having the benefit of the present application. Therefore, the application, in its broader aspects, is not limited to the specific details, illustrative examples shown, or any apparatus referred to. Departures may be made from such details, examples, and apparatuses without departing from the spirit or scope of the general inventive concept.

[0093] The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1. A method for propagating a wireless signal in an electromagnetically-attenuating ionic solution, comprising one or more of:

transmitting a signal into the electromagnetically-attenuating ionic solution by applying a time-varying excitation field to the electromagnetically-attenuating ionic solution, the signal corresponding to the time-varying excitation field, the time-varying excitation field comprising one or more of: an electrical component and a magnetic component; and

receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution,

the signal being wirelessly propagated in the electromagnetically-attenuating ionic solution.

2. The method of claim 1, the signal comprising one or more of an analog component and a digital component.

3. The method of claim 1, comprising transmitting the signal into the electromagnetically- attenuating ionic solution and receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution.

4. The method of claim 3, whereby the signal is wirelessly communicated via the electromagnetically-attenuating ionic solution.

5. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution comprising one or more of: electrically detecting the signal and magnetically detecting the signal.

6. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution excluding one or more of: detecting an electromagnetic wave corresponding to the signal and detecting a mechanical acoustic wave corresponding to the signal.

7. The method of claim 1, at least a portion of the signal being carried in the electromagnetically-attenuating ionic solution by other than an electromagnetic wave.

8. The method of claim 1, the electromagnetically-attenuating ionic solution substantially attenuating an electromagnetic wave component corresponding to the signal such that receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution substantially excludes receiving the electromagnetic wave component.

9. The method of claim 1, the signal corresponding to data encoded in the time-varying excitation field, the data comprising one or more of: digital data and analog data.

10. The method of claim 1, further comprising forming the signal by encoding data in the time-varying excitation field.

11. The method of claim 1, further comprising forming the signal by encoding data and modulating the encoded data in the time-varying excitation field.

12. The method of claim 1, further comprising forming the signal by encoding data and modulating the encoded data in the time-varying excitation field by one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying amplitude shift keying, and software defined radio.

13. The method of claim 1, further comprising obtaining data encoded in the signal by one or more of: decoding at least a portion of the signal and demodulating at least a portion of the signal.

14. The method of claim 1, further comprising:

forming the signal by encoding data in the time-varying excitation field; and

obtaining data encoded in the signal by one or more of: decoding at least a portion of the signal and demodulating at least a portion of the signal,

whereby the encoded modulated data is wirelessly communicated through the

electromagnetically-attenuating ionic solution.

15. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution comprising detecting from the electromagnetically-attenuating ionic solution at least a portion of one or more of: the time- varying excitation field and an excitation in the electromagnetically-attenuating ionic solution corresponding to the time-varying excitation field.

16. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution comprising operatively coupling one or more signal detectors to the electromagnetically-attenuating ionic solution, the one or more signal detectors being one of: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution.

17. The method of claim 1, transmitting the signal into the electromagnetically-attenuating ionic solution comprising operatively coupling one or more signal emitters to the electromagnetically-attenuating ionic solution, the one or more signal emitters being one of: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically- attenuating ionic solution.

18. The method of claim 1, receiving the signal comprising detecting one or more of: an electrical signature corresponding to the time-varying excitation field and a magnetic signature corresponding to the time-varying excitation field.

19. The method of claim 1, transmitting the signal into the electromagnetically-attenuating ionic solution comprising creating in the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

20. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution comprising detecting from the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

21. The method of claim 1, comprising transmitting the signal and receiving at least a portion of the signal to provide wireless communication via the electromagnetically attenuating ionic solution that is one or more of: simplex, half duplex, full duplex, time division duplex, and frequency division duplex.

22. The method of claim 1, applying the time-varying excitation field to the electromagnetically-attenuating ionic solution comprising driving a transmitter via buffered amplification, the transmitter being driven by the buffered amplification at one or more of: greater than about unity gain, about unity gain, or less than about unity gain.

23. The method of claim 22, the buffered amplification being switched or unswitched.

24. The method of claim 22, further comprising generating the signal and subjecting the signal to the buffered amplification effective to drive the transmitter.

25. The method of claim 22, the signal comprising a carrier component and a modulated signal component, further comprising generating the carrier component, generating the modulated component, and modulating the carrier component with the modulated component to generate the signal.

26. The method of claim 1, receiving at least a portion of the signal from the electromagnetically-attenuating ionic solution comprising:

collecting the at least a portion of the signal in a receiver, the signal being analog or digital; and

subjecting the signal collected by the receiver to one or more of: amplitude

demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio.

27. The method of claim 1, the portion of the signal received from the electromagnetically- attenuating ionic solution comprising a common mode component, further comprising collecting a common mode ground reference and rejecting at least a portion of the common mode component by difference using the common mode ground reference to provide a difference mode signal.

28. The method of claim 1, comprising wirelessly propagating the signal in the electromagnetically-attenuating ionic solution over a distance in meters of at least about one or more of: 1, 5, 10, 15, 20, 25, 50, 75, 100, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, 7500, and 10,000.

29. The method of claim 1, comprising wirelessly propagating the signal in the electromagnetically-attenuating ionic solution at a frequency range in MHz of about one or more of: 1 to 100, 20 to 80, 20 to 65, 30 to 50, 35 to 45, 35 to 40, and 50 to 60.

30. The method of claim 1, the electromagnetically-attenuating ionic solution comprising one or more of: seawater, brine, fracking fluid, surface water, ground water, waste water, treated water, tap water, a biological fluid, a bioreactor fluid, an industrial process fluid, and an ionic solvent.

31. The method of claim 1, the electromagnetically-attenuating ionic solution comprising a conductivity of in Siemens/meter at 25 °C of at least one or more of about: 0.001, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, and 25.

32. The method of claim 1, the signal being transmitted into a body of water from or received from a body of water by one of: a surface vessel, a submarine, a drone, an unmanned submersible vehicle, a buoy, a sensor, an amphibious airplane, a weapon, a relay station, a navigational beacon, a distress beacon, a flight data recorder, a voyage data recorder, a scientific instrument, a personal diving device, a personal floatation device, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment, a monitoring station, an aircraft configured to operatively couple at least at least one of the transceiver and the receiver to the body of water while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, a fixed marine installation, and a fixed shore installation.

33. The method of claim 1, comprising wirelessly propagating the signal in the electromagnetically-attenuating ionic solution with a dependency of signal variation with distance r of about 1/r.

34. The method of claim 1, comprising conducting the transmitting the signal or receiving at least a portion of the signal using a carbon electrode, or other electrical conductor protected from corrosion, in contact with the electromagnetically-attenuating ionic solution.

35. A system for transmitting or receiving a signal propagated in an electromagnetically- attenuating ionic solution, the system comprising one or more of:

a transmitter apparatus comprising a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically-attenuating ionic solution, the time-varying excitation field carrying a corresponding signal, the signal generator and the transmitter being configured together to create the time-varying excitation field comprising one or more of: an electrical component and a magnetic component; and

a receiver apparatus comprising a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

36. The system of claim 35, configured for one or more of: digital operation and analog operation.

37. The system of claim 35, comprising the transmitter apparatus and the receiver apparatus.

38. The system of claim 35, the transmitter apparatus and the receiver apparatus being configured together in the form of a transceiver.

39. The system of claim 35, one or more of the transmitter and the signal receiver being configured effective to respectively transmit and receive the time-varying excitation field with respect to the electromagnetically-attenuating ionic solution under one or more conditions of being: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically- attenuating ionic solution.

40. The system of claim 35, the electromagnetically-attenuating ionic solution comprising one or more of: seawater, brine, fracking fluid, surface water, ground water, waste water, treated water, tap water, a biological fluid, a bioreactor fluid, an industrial process fluid, and an ionic solvent.

41. The system of claim 35, the electromagnetically-attenuating ionic solution comprising a conductivity of in Siemens/meter at 25 °C of at least one or more of about: 0.001, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, and 25.

42. The system of claim 35, the signal generator comprising one or more of: a local oscillator, a digital signal generator, an analog signal generator, an audio signal generator, a photodiode, and a charge coupled device.

43. The system of claim 35, further comprising a buffer driver operatively coupled to the signal generator and the transmitter, the buffer driver being configured to operate greater than about unity gain, about unity gain, or less than about unity gain.

44. The system of claim 43, the buffer driver being switched or unswitched.

45. The system of claim 35, one or more of the transmitter and the signal receiver each independently comprising one or more of: a conducting coil and an electrode structure.

46. The system of claim 35, one or more of the transmitter and the signal receiver each independently comprising a conducting coil comprising a number of turns of about one or more of: 1, 2, 3, 4, 5, 7, 9, 11, 13, 15, 20, 25, 30, 35, 40, 50, 100, 200, 250, 500, 750, 1000, 2000, 2500, 5000, 7500, and 10,000.

47. The system of claim 35, one or more of the transmitter and the signal receiver each independently comprising a conducting coil characterized by an average diameter in centimeters of at least about one of: 1, 2, 3, 4, 5, 7, 9, 11, 13, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 500, 750, 1000, 1250, 1500, 1750, and 2000.

48. The system of claim 35, one or more of the transmitter and the signal receiver each independently comprising a carbon electrode.

49. The system of claim 35, one or more of the transmitter and the signal receiver comprising one or more of: a corrosion-resistant conductor, a corrosion-resistant coating, a carbon electrode, and a water resistant coating; the corrosion-resistant conductor, the corrosion-resistant coating, the carbon electrode, and the water-resistant coating being at least partly resistant to the electromagnetically-attenuating ionic solution, and the corrosion resistant coating and the water- resistant coating each being permeable to the signal.

50. The system of claim 35, the signal receiver being configured effective to receive the time-varying excitation field from the electromagnetically-attenuating ionic solution under one or more conditions of being: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution.

51. The system of claim 35, the receiver apparatus further comprising a high frequency amplifier that may be differential or single-ended, the signal receiver being operatively coupled to one or more inputs of the high frequency amplifier and the detector being operatively coupled to one or more outputs of the high frequency amplifier.

52. The system of claim 51, the receiver apparatus further comprising a ground coil operatively coupled to the one or more inputs of the difference amplifier, the difference amplifier being configured to detect a common mode ground reference in the ground coil and to reject the common mode ground reference from a signal received at the signal receiver.

53. The system of claim 52, the signal receiver comprising a coil having a first number of turns compared to a second number of turns of the ground coil, the first number of turns being, compared to the second number of turns, one of: greater, lesser, or the same.

54. The system of claim 35, the transmitter apparatus comprising a modulator operatively coupled to encode the signal using one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying, amplitude shift keying, and software defined radio.

55. The system of claim 35, the receiver apparatus comprising a demodulator operatively coupled to decode the signal using one or more of: amplitude demodulation, frequency demodulation, quadrature amplitude demodulation (QAM), frequency shift keying demodulation, phase shift keying demodulation, amplitude shift keying demodulation, and software defined radio.

56. The system of claim 35, the receiver apparatus further comprising an output module operatively coupled to the signal receiver, the output module being configured to convert the signal to one or more of: a visible signal and an audible signal.

57. The system of claim 35, the transmitter apparatus being configured to apply the time- varying excitation field to the electromagnetically-attenuating ionic solution to wirelessly propagate the signal into the electromagnetically-attenuating ionic solution.

58. The system of claim 35, the receiver apparatus being configured to wirelessly receive at least a portion of the signal from the electromagnetically-attenuating ionic solution, the signal being wirelessly propagated in the electromagnetically-attenuating ionic solution.

59. The system of claim 35, the receiver apparatus being configured to receive the signal from the electromagnetically-attenuating ionic solution via one or more of: electrically detecting the signal and magnetically detecting the signal.

60. The system of claim 35, the receiver apparatus being configured to receive the signal from the electromagnetically-attenuating ionic solution excluding one or more of: detecting an electromagnetic wave corresponding to the signal and detecting a mechanical acoustic wave corresponding to the signal.

61. The system of claim 35, being configured such that at least a portion of the signal is carried in the electromagnetically-attenuating ionic solution by other than an electromagnetic wave.

62. The system of claim 35, being configured to propagate the signal in the electromagnetically-attenuating ionic solution, the electromagnetically-attenuating ionic solution substantially attenuating an electromagnetic wave component corresponding to the signal.

63. The system of claim 35, the signal corresponding to data encoded in the time-varying excitation field.

64. The system of claim 35, the signal corresponding to data encoded in the time-varying excitation field, the data comprising one or more of: digital data, analog data, a video signal, and an audio signal.

65. The system of claim 35, the transmitter apparatus being configured to form the signal to be transmitted by encoding data in the time-varying excitation field.

66. The system of claim 35, the receiver apparatus being configured to receive from the electromagnetically-attenuating ionic solution at least a portion of one or more of: the time- varying excitation field and an excitation in the electromagnetically-attenuating ionic solution corresponding to the time-varying excitation field.

67. The system of claim 35, the receiver apparatus being configured to detect one or more of: an electrical signature corresponding to the time-varying excitation field and a magnetic signature corresponding to the time-varying excitation field.

68. The system of claim 35, the transmitter apparatus being configured to apply the time- varying excitation field to create in the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

69. The system of claim 35, the receiver apparatus being configured to detect from the electromagnetically-attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time-varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

70. The system of claim 35, the receiver apparatus and the transmitter apparatus being configured to provide wireless communication via the electromagnetically attenuating ionic solution that is one or more of: simplex, half duplex, full duplex, time division duplex, and frequency division duplex.

71. The system of claim 35, configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution over a distance in meters of at least about one or more of: 0.1, 0.25, 0.5, 0.75, 1, 5, 10, 15, 20, 25, 50, 75, 100, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, 7500, and 10,000.

72. The system of claim 35, configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution at a frequency range in MHz of about one or more of: 1 to 100, 20 to 80, 20 to 65, 30 to 50, 35 to 45, 35 to 40, and 50 to 60.

73. The system of claim 35, at least one of the transmitter and the receiver being coupled to a platform configured to be operatively coupled to a body of water, the platform comprising one of: a surface vessel, a submarine, a drone, an unmanned submersible vehicle, a buoy, a sensor, an amphibious airplane, a weapon, a relay station, a navigational beacon, a distress beacon, a flight data recorder, a voyage data recorder, a scientific instrument, a personal diving device, a personal floatation device, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment, a monitoring station, an aircraft configured to operatively couple at least at least one of the transmitter and the receiver to the body of water while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, a fixed marine installation, and a fixed shore installation.

74. A communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution, the communications network comprising a plurality of transmitting apparatuses and a plurality of receiving apparatuses, the plurality of transmitting apparatuses and the plurality of receiving apparatuses being configured to be wirelessly coupled through the electromagnetically-attenuating ionic solution,

each transmitter apparatus comprising a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically- attenuating ionic solution, the time-varying excitation field carrying a corresponding signal, the signal generator and the transmitter being configured together to create the time-varying excitation field comprising one or more of: an electrical component and a magnetic component; and

each receiver apparatus comprising a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

75. The communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution of claim 74, the communications network comprising a plurality of transceivers, each transceiver comprising one said transmitter apparatus and one said receiver apparatus, the plurality of transceivers being configured to be wirelessly coupled through the electromagnetically-attenuating ionic solution.

76. The communications network of claim 74, configured for one or more of: digital operation and analog operation.

77. The communications network of claim 75, each transceiver being configured effective to apply the time-varying excitation field to the electromagnetically-attenuating ionic solution under one or more conditions of being: in contact with the electromagnetically-attenuating ionic solution, immersed in the electromagnetically-attenuating ionic solution, and separated from the electromagnetically-attenuating ionic solution.

78. The communications network of claim 74, the electromagnetically-attenuating ionic solution comprising one or more of: seawater, brine, fracking fluid, surface water, ground water, waste water, treated water, tap water, a biological fluid, a bioreactor fluid, an industrial process fluid, and an ionic solvent.

79. The communications network of claim 74, the electromagnetically-attenuating ionic solution comprising a conductivity of in Siemens/meter at 25 °C of at least one or more of about: 0.001, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, and 25.

80. The communications network of claim 75, the signal generator in each transceiver comprising one or more of: a local oscillator, a digital signal generator, an analog signal generator, an audio signal generator, a photodiode, and a charge coupled device.

81. The communications network of claim 75, one or more of the transmitter and the signal receiver in each transceiver each independently comprising one or more of: a conducting coil and an electrode structure.

82. The communications network of claim 75, one or more of the transmitter and the signal receiver in each transceiver each independently comprising a carbon electrode.

83. The communications network of claim 75, the transmitter and the signal receiver in each transceiver comprising one or more of: a corrosion-resistant conductor, a corrosion-resistant coating, a carbon electrode, and a water resistant coating; the corrosion-resistant conductor, the corrosion-resistant coating, the carbon electrode, and the water-resistant coating being at least partly resistant to the electromagnetically-attenuating ionic solution, and the corrosion resistant coating and the water-resistant coating each being permeable to the signal.

84. The communications network of claim 75, the receiver apparatus in each transceiver further comprising a high frequency amplifier, the signal receiver being operatively coupled to one or more inputs of the high frequency amplifier and the detector being operatively coupled to one or more outputs of the high frequency amplifier.

85. The communications network of claim 84, the receiver apparatus in each transceiver further comprising a ground coil operatively coupled to the one or more inputs of the high frequency amplifier, the high frequency amplifier being configured to detect a common mode ground reference in the ground coil and to reject the common mode ground reference from a signal received at the signal receiver.

86. The communications network of claim 75, each transceiver comprising at least one modulator operatively coupled to encode and/or decode the signal using one or more of: amplitude modulation, frequency modulation, quadrature amplitude modulation (QAM), frequency shift keying, phase shift keying, amplitude shift keying, and software defined radio.

87. The communications network of claim 75, the receiver apparatus in each transceiver further comprising an output module operatively coupled to the signal receiver, the output module being configured to convert the signal to one or more of: a visible signal and an audible signal.

88. The communications network of claim 75,

the transmitter apparatus in each transceiver being configured to apply the time-varying excitation field to the electromagnetically-attenuating ionic solution to wirelessly propagate the signal into the electromagnetically-attenuating ionic solution with a dependency of signal variation with distance r of about 1/r; and

the receiver apparatus in each transceiver being configured to wirelessly receive at least a portion of the signal from the electromagnetically-attenuating ionic solution with a dependency of signal variation with distance r of about 1/r.

89. The communications network of claim 74, being configured such that the signal is substantially carried in the electromagnetically-attenuating ionic solution by other than an electromagnetic wave.

90. The communications network of claim 74, the signal corresponding to data encoded in the time-varying excitation field, the data comprising one or more of: digital data, analog data, a video signal, and an audio signal.

91. The communications network of claim 75, the receiver apparatus in each transceiver being configured to:

receive from the electromagnetically-attenuating ionic solution at least a portion of one or more of: the time-varying excitation field and an excitation in the electromagnetically- attenuating ionic solution corresponding to the time-varying excitation field; and

detect one or more of: an electrical signature corresponding to the time-varying excitation field, a magnetic signature corresponding to the time-varying excitation field, an excited plurality of ions corresponding to the time-varying excitation field, and an ion acoustic wave corresponding to the time-varying excitation field.

92. The communications network of claim 75, the transmitter apparatus in each transceiver being configured to apply the time-varying excitation field to create in the electromagnetically- attenuating ionic solution one or more of: an excited plurality of ions corresponding to the time- varying excitation field and an ion acoustic wave corresponding to the time-varying excitation field.

93. The communications network of claim 74, configured to provide wireless communication via the electromagnetically attenuating ionic solution that is one or more of: simplex, half duplex, full duplex, time division duplex, and frequency division duplex.

94. The communications network of claim 74, configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution between each pair of transceivers in the plurality of transceivers over a distance in meters of at least about one or more of: 1, 5, 10, 15, 20, 25, 50, 75, 100, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, 7500, and 10,000.

95. The communications network of claim 74, configured to wirelessly propagate the signal in the electromagnetically-attenuating ionic solution at a frequency range in MHz of about one or more of: 1 to 100, 20 to 80, 20 to 65, 30 to 50, 35 to 45, 35 to 40, and 50 to 60.

96. The communications network of claim 75, the plurality of transceivers being configured to be distributed among and communicate through a body of water between a plurality of platforms configured to be operatively coupled to the body of water, the plurality of platforms comprising one or more: surface vessels, submarines, drones, unmanned submersible vehicles, buoys, sensors, amphibious airplanes, weapons, relay stations, navigational beacons, distress beacons, flight data recorders, voyage data recorders, scientific instruments, personal diving devices, personal floatation devices, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment, monitoring stations, aircraft configured to operatively couple at least one said transceiver to the seawater while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, fixed marine installations, and fixed shore installations.

97. The communications network of claim 74, configured as a broadcast communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution, comprising:

at least one said transmitter apparatus and a plurality of said receiver apparatuses configured together as the broadcast communications network, the broadcast communications network being configured to wirelessly broadcast the signal from each transmitter apparatus through the electromagnetically-attenuating ionic solution to each of the plurality of receiver apparatuses; each transmitter apparatus comprising a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically- attenuating ionic solution, the time-varying excitation field carrying a corresponding signal, the signal generator and the transmitter being configured together to create the time-varying excitation field comprising one or more of: an electrical component and a magnetic component; and

98. The broadcast communications network of claim 97, each transmitter and each receiver being configured to be distributed among and communicate through a body of water between a plurality of platforms configured to be operatively coupled to the body of water, the plurality of platforms comprising one or more: surface vessels, submarines, drones, unmanned submersible vehicles, buoys, sensors, amphibious airplanes, weapons, relay stations, navigational beacons, distress beacons, flight data recorders, voyage data recorders, scientific instruments, personal diving devices, personal floatation devices, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment, monitoring stations, aircraft configured to operatively couple at least one said transmitter to the seawater while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, fixed marine installations, and fixed shore installations.

99. The communications network of claim 74, configured as a listening communications network for transmitting and receiving a signal propagated in an electromagnetically-attenuating ionic solution, comprising:

a plurality of said transmitter apparatuses and at least one said receiver apparatus configured as the listening communications network, the listening communications network being configured to wirelessly transmit the signal from the plurality of transmitter apparatuses through the electromagnetically-attenuating ionic solution to each receiver apparatus;

each transmitter apparatus comprising a signal generator operatively coupled to a transmitter effective to apply a time-varying excitation field to the electromagnetically- attenuating ionic solution, the time-varying excitation field carrying a corresponding signal, the signal generator and the transmitter being configured together to create the time-varying excitation field comprising one or more of: an electrical component and a magnetic component; and each receiver apparatus comprising a signal receiver operatively coupled to a detector effective to receive at least a portion of the signal from the electromagnetically-attenuating ionic solution.

100. The listening communications network of claim 99, each transmitter and each receiver being configured to be distributed among and communicate through a body of water between a plurality of platforms configured to be operatively coupled to the body of water, the plurality of platforms comprising one or more: surface vessels, submarines, drones, unmanned submersible vehicles, buoys, sensors, amphibious airplanes, weapons, relay stations, navigational beacons, distress beacons, flight data recorders, voyage data recorders, scientific instruments, personal diving devices, personal floatation devices, rescue equipment, fishing equipment, construction equipment, mining equipment, petroleum recovery equipment, monitoring stations, aircraft configured to operatively couple at least one said transmitter to the seawater while airborne, oil or natural gas infrastructure, transportation infrastructure, undersea cable communications infrastructure, fixed marine installations, and fixed shore installations.