AIR, LAND AND SEA WIRELESS OPTICAL TELECOMMUNICATION NETWORK (ALSWOT)
20200322055 ยท 2020-10-08
Inventors
Cpc classification
H04B10/1129
ELECTRICITY
International classification
Abstract
Systems and methods are disclosed with a plurality of remote controlled, located and monitored platform relays for global data transmission and reception, and at least one relay linked to a maritime vessel, a satellite and an air-based vehicle.
Claims
1. A system, comprising: a plurality of remote controlled, located and monitored platform relays for global data transmission and reception, and at least one relay linked to a maritime vessel, a satellite and an air-based vehicle.
2. The system of claim 1, wherein a transceiver coupled to one or more relays receives Internet data on land, sea, or air.
3. The system of claim 1, wherein the relay comprises a land-based relay.
4. The system of claim 1, wherein the relay comprises an air-based relay.
5. The system of claim 1, wherein the relay comprises a water-based relay.
6. The system of claiml, wherein the relay comprises a satellite-based relay.
7. The system of claim 1, wherein the relay comprises a land-based relay in communication with an air-based relay, a satellite-based relay and a water-based relay.
8. The system of claim 1, wherein the relays form a mesh-network to avoid reliance on a point to point data transmission.
9. The system of claim 1, comprising a mesh-network to prevent hostile sources from gaining access to communication system data
10. The system of claim 1, comprising real time migration and routing of data between alternate station locals to enhance cyber security.
11. The system of claim 1, wherein the relay is moveable.
12. The system of claim 1 wherein the relay is anchored.
13. The system of claim 1, comprising real time monitoring and location of air vehicles world-wide.
14. The system of claim 1, comprising the rebroadcast of frequencies in the electromagnetic spectrum while operating above International and EEZ waters.
15. The system of claim 1, comprising the rebroadcast of transmission frequencies in the electromagnetic spectrum not assigned for use over International and EEZ Waters.
16. The system of claim 1, comprising the rebroadcast of transmission frequencies of claims 14 and 15 in territorial waters.
17. The system of claim 1, wherein the relays communicate with LEO and Geostationary Satellite for Global Coverage.
18. The system of claim 1, comprising a battery power storage device that is charged by energy generated from fossil fuels, wave, wind, solar, or electromagnetic energy.
19. The system of claim 1, comprising one or more servers communicating with the relays, wherein the servers are positioned on maritime vessels moveable and operable in International and EEZ waters.
20. The system of claim 1, comprising a stabilizer coupled to a relay platform.
21. The system of claim 1, comprising vertical and horizontal thrusters coupled to a relay platform.
22. The system of claim 1, comprising separate groupings of three geo-positioning receivers with each grouping a predetermined vertical distance from the other.
23. The system of claims 1 and 22, comprising receivers and output signals that independently establishing latitude, longitude, and height above local mean sea level
24. The system of claims 1, 22, 23 comprising the construct of a center point, a radius and a plane using principles of geometry and providing output signals.
25. The system of claims 1, 22, 23 and 24 comprising a best fit connection of center points to establish a platform tower vertical axis.
26. The system of claims 1 and 24, comprising three or more liquid leveling sensors, spring mounted accelerometers, or other devices positioned at rays 120 degrees from each other used to level the planar surface
27. The system of claims 1,23 and 26, comprising feedback signals to an electronic control unit to operate stabilizers and thrusters
28. The system of claim 17, comprising a gimbal mounted transceiver attached to the platform tower.
29. The system of claim 1, comprising a thruster system powered by mechanical drives of fossil fuel powered engines.
30. The system of claim 1, comprising a thruster system powered by water jet drive.
31. The system of claim 1, comprising a thruster system driven by electric motors.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0087] In the detailed description which follows, reference will be made to the drawing comprised of the following figures:
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DETAILED DESCRIPTION
[0095] In this section the present invention is described with reference to the accompanying drawings in which functional embodiments of the invention are shown.
[0096] This invention may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0097] Disclosed herein is a System of Systems (SOS) that exploits the simplicity of a multitude of motion Stabilized, Floating, Drone, Platform Towers (SFDPT) equipped with stabilized directionally controlled transceivers to relay telecommunication data using energy in the wavelength from 104 to 10-8 meters. A multitude of SFDPTs deployed in conjunction with stabilized aligned towers (SAT) placed on maritime vessels, drilling platforms, UAVs, dirigibles, manned and un-manned aircraft creates a data communication network that allows global coverage.
[0098] Air Land and Sea Wireless Optical Data Transmission (ALSWOT), is a system of motion stabilized and directed energy transmission, relay, and reception of telecommunication energy, using a plethora of remotely controlled and autonomously operated maritime relays, each self-contained and operating autonomously as part of a fully meshed network of transceivers. These transceivers placed on maritime platforms, buoys, vessels, drilling platforms, etc., enhance global transmission rates, ranges, bandwidth and performance by linking to manned and unmanned aircraft, satellites, dirigibles and other air vehicles. The system provides a fully meshed global WI-FI data and telecommunication network to serve the entire globe without the need for submarine cable data transmission. The fully linked, variably routed, fully meshed, next generation, state-of-the-art spiral development system is designed to be continuously upgradeable and provide global transmission of internet and telecommunication data globally enhancing coverage, performance, including unlimited transmission rates and volume. ALSWOT provides enhanced security, affordability and global availability to data networks.
[0099] The Drone Platform Towers (SFDPT) are remotely positioned, located and controlled allowing multiple continuously variable data transmission routes. The SOS operates primarily in International and EEZ Waters but is also deployed in coastal territorial and littoral waters along continents, island nations, islands, fjords, and up major river systems. ALSWOT globally distributes Wi-Fi traffic data via the offshore network before handing off data to land-based systems for local distribution. The SOS provides a robust economical transmission network to compete against limited capacity fiber optic-based submarine cable systems while eliminating many of disadvantages these stationary systems inherently possess including limited transmission rates.
[0100] This offshore Wi-Fi SOS network provides an efficient low-cost affordable alternate to oceanic submarine and below ground coastal fiber optic cable systems currently deployed. The SOS extends and enhances global communication networks to ocean, coastal and river areas not presently covered because economics do not support the capital investment required for cable placement. Air Land and Sea Wireless Optical Data Transmission (ALSWOT) expands capabilities of present systems by (a) expanding transmission data capacity and (b) increasing global coverage. The expanded capabilities benefit numerous institutions, organizations, and individuals as noted herein. The SOS enhances the study of global environmental science, global marine weather and life science, permits low or sea level hurricane study, rogue wave investigation, detailed ocean current investigation and assessment, ocean temperature information, and enhances many scientific endeavors while at the same time expanding access to global communication networks by less affluent individuals. By providing access and reaching less affluent individuals global illiteracy is reduced and on-line mass education is significantly enhanced. The SOS has flexibility to relocate and reposition assets in response to real time demand caused by natural or other types of disaster.
[0101] The SOS provides a platform base to maintain and deploy autonomous drones to study coral reefs, mangrove swamps, monitor Blue Carbon and evaluate multiple other environmental factors whose continuous monitoring and study promote a healthy global environment.
[0102] ALSWOT, enhances global transmission rates, ranges, traffic, routes and performance by also linking to manned and unmanned aircraft, satellites, dirigibles and air vehicles. The system provides a fully meshed incrementally expandable global WI-FI data and telecommunication network that not only serves the entire global population but also the entire global surface area. The fully linked, constantly variable routing, fully meshed, next generation, state-of-the-art, spiral development system is continuously and incrementally upgradeable. ALSWOT SOS provides global transmission of internet and telecommunication data coverage to billions of humans not presently served due to economic factors and globally enhances coverage, performance, affordability and availability.
[0103] One or more devices (alternatively designated as units, elements, systems, terminals, devices, leads or connections) are optional in the embodiments. The elements may be interconnected and or used in various configurations. In the figures and relevant descriptions of the figures, as well as in the specifications of this disclosure, some of the units or elements are optional and are not required for certain applications, embodiments and or structures. In this document the term signal has the most generic meaning used in the prior art and includes electrical, acoustical, infrared , X-ray, fiber optics, light sound, position, altitude ,diagnostics, beat , density, and other sensor or device or human being or animal or object generated or processed waveforms, images, pictures, symbols, wavelets, wave shapes and analog or digital or hybrid analog and digital signals.
[0104] Definitions
[0105] The following terms contained in this document are defined as follows:
[0106] Ray: A scalar starting at a point extending to infinity
[0107] Axis: A scalar connecting two points extending to infinity in both directions
[0108] EEZ: Economic Enterprise Zone
[0109] Co-ordinate System: A mutually perpendicular set of axes with directions noted as variables X, Y and Z. Translation along the X axis is referred to as surge, translation along the Y axis is referred to as sway, and translation along the Z axis is referred to as heave. Rotation around the X axis is referred to as pitch, rotation around the Y axis is referred to as roll, and rotation
[0110] around the Z axis is referred to as yaw.
[0111] Acronyms
[0112] To facilitate comprehension of the current disclosure frequently used acronyms and or abbreviations used in the prior art and/or in the current disclosure are highlighted in the following acronyms: [0113] 2G Second generation or 2nd generation wireless or cellular system [0114] 3D three dimensional [0115] 3G Third Generation or 3rd generation wireless or cellular system [0116] 4G Fourth Generation wireless or cellular system [0117] 5G Fifth Generation or future generation [0118] AM Amplitude Modulation [0119] AMC Adaptive Modulation and Coding [0120] ACM Adaptive Coding and Modulation [0121] Bluetooth Wireless system standardized by the Bluetooth organization [0122] BPSK Binary Phase Shift Keying [0123] BRA Bit Rate Agile or Bit Rate Adaptive [0124] BST Base Station Transceiver [0125] BWA Broadband Wireless Access [0126] CC cross-correlation or cross-correlate [0127] CCOR cross-correlation or cross-correlate [0128] CDMA Code Division Multiple Access [0129] CM Clock Modulated [0130] CS Code Selectable [0131] CSAA Continuously Self-Aligned Antennae [0132] CSMA Collision Sense Multiple Access [0133] CL Clock Shaped [0134] COS Co-Ordinate System used for maritime vessels [0135] DECT Digital European Cordless Telecommunication [0136] DOF Named Degrees of Freedom Used in Maritime Systems [0137] DS-SS Direct Sequence Spread Spectrum [0138] EDGE Enhanced Digital GSM Evolution; Evolution of GSM or E-GSM [0139] EEZ Waters Economic Enterprise Zone Waters [0140] ECA Electrically Conductive Adhesives [0141] ECP Electrically Conductive Paints [0142] ECM Electrically Conductive Materials [0143] ECS Electrically Conductive Sealants [0144] EMI Electromagnetic Interference [0145] FA Frequency Agile (selectable or switched IF or RF frequency) [0146] FDM Frequency Division Multiplex [0147] FH-SS Frequency Hopped Spread Spectrum [0148] FLIR Forward Looking Infra-Red [0149] GFLS Gravity Fluid Leveling System [0150] FQPSK Fehr's QPSK or Feher's patented QPSK [0151] FOC Fiber Optic Communication [0152] FSK Frequency Shift Keying [0153] GFSK Gaussian Frequency Shift Keying [0154] GPS Global Positioning System [0155] GPRS General Packet Radio Service [0156] GMSK Gaussian Minimum Shift Keying [0157] GSM Global Mobile System or Global System Mobile [0158] HDR Hybrid Defined Radio [0159] IEEE 802 Institute of Electrical and Electronics Engineers Standard Number 802 [0160] IR Infrared [0161] LAN Local Area Network [0162] LINA Linearly amplified or Linear amplifier or linearized amplifier [0163] LORAN-C Long Range Radio Navigation SystemLegacy System [0164] LR Long Response [0165] LSS Local Sea Level [0166] MSL Mean Sea Level [0167] MES Modulation Embodiment Selectable [0168] MFS Modulation Format Selectable [0169] MIMO Multiple Input Multiple Output [0170] MISO Multiple Input Single Output [0171] MMIMO Multimode Multiple Input Multiple Output [0172] MSDR Multiple Software Defined Radio [0173] NLA Non-Linearly Amplified or Non-Linear Amplifier [0174] NQM non-quadrature modulation [0175] NonQUAD non-quadrature modulator [0176] NRZ Non-Return to Zero [0177] OFDM Orthogonal Frequency Division Multiplex [0178] PA Platform Alignment [0179] PDA Personal Digital Assistants [0180] PDD Position Determining Device [0181] PDE Position Determining Entity [0182] PS Platform Stabilization [0183] PTT push to talk [0184] QUAD Quadrature; also used for quadrature modulation [0185] quad Quadrature; also used for quadrature modulation [0186] QM Quadrature Modulation [0187] QPSK Quadrature Phase Shift Keying [0188] RC Remote Control [0189] RFID Radio Frequency Identification [0190] RFAM Radio Frequency Absorbent Materials [0191] Rx receive [0192] SDR Software Defined Radio (SDR) [0193] SFDPT Stabilized Floating Drone Platform and Towers (SFDPT) [0194] SIMO Single Input Multiple Output [0195] SSAT Subsurface Stabilizers and Thrusters [0196] STCS Shaped Time Constrained Signal [0197] MSDR Multiple Software Defined Radio [0198] TBD to be decided [0199] TCS Time Constrained Signal [0200] TDM Time Division Multiplex [0201] TDMA Time Division Multiple Access [0202] PTT Platform Telescopic Towers [0203] TR transceiver (transmitter-receiver) [0204] Tx transmit [0205] TV television [0206] UMTS Universal Mobile Telecommunication System [0207] UNB Ultra narrowband or Ultra narrow band [0208] URC Universal Remote Control [0209] UWB Ultrawideband or ultra-wideband [0210] UWN Ultrawideband-Ultra Narrow Band [0211] VoIP Video over Internet Protocol [0212] VoIP Voice over Internet Protocol [0213] W waveform, wavelet or wave (signal element) [0214] WAN Wide Area Network [0215] WCDMA Wideband Code Division Multiple Access W-CDMA Wideband Code Division Multiple Access [0216] Wi Fi Wireless Fidelity or related term used for systems such as IEEE 802.x_standardized systems; See also Wi-Fi [0217] Wi-Fi wireless fidelity [0218] WLAN Wireless Local Area Network [0219] www World Wide Web (or WWW or) WEB [0220] XCor cross-correlation or cross-correlator or cross-correlate
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[0224] The earth station may in turn be connected to a public switched telephone network, allowing communications between satellite radiotelephones, and communications between satellite radiotelephones and conventional terrestrial cellular radiotelephones or landline telephones. The satellite radiotelephone system may utilize a single antenna beam covering the entire area served by the system, or, as shown in
[0225] The radiotelephone systems require more power than conventional cellular stations and are used in areas where the small number of thinly scattered users and/or the rugged topography may make conventional landline telephone or cellular telephone infrastructure technically or economically impractical. In the ocean regions, many of the natural features which may make it commercially impractical to install conventional landline or cellular telephone infrastructures will not impede signals traveling between radiotelephones and satellites. In the ocean, LOS and OTH techniques can go long distances due to the absence of dense foliage, hills, mountain ranges, and adverse weather conditions may all impede the relatively weak signals transmitted by satellites and radiotelephones.
[0226] The system of
[0227] SOS telecommunications repeaters according to the invention may also be contained in single, portable, hand-held housings. These portable repeaters may have many features including a flap, or cover, into which a patch antenna assembly may be incorporated for receiving downlink signals and retransmitting uplink signals. The flap patch antenna assembly is preferably attached to the housing of the portable unit using a hinge or swivel which allows positioning of the flap/patch antenna assembly in relation to satellites to achieve a further increase in link margin. The portable repeaters may also include various types of extensions used to support the repeater housing in an operating position. According to one embodiment of the present invention, the satellite telecommunications repeaters may employ one or more legs rotatably attached to the hand-held housing to support the repeater in an operating position.
[0228] According to another aspect of the present invention, the antennas of the SOS telecommunications repeaters used for receiving downlink signals from satellites and for retransmitting uplink signals to satellites may be aligned to SOS communicators using conventional methods such as mechanical tracking and beam steering to thereby further increase link margin.
[0229] According to another aspect of the present invention, the antennas of portable embodiments of the SOS telecommunications repeaters of the present invention may be physically aligned to transmitting satellites by users by providing a circuit which determines the strength of signals traveling between the satellites and the repeater. By moving the repeater housing as a unit, or by only moving the antennas, until the signal strength increases, better alignment and potentially increased link margin may occur.
[0230] According to another aspect of the present invention, a sleep circuit is provided for the SOS telecommunications repeaters which can place the repeater in sleep, or stand-by, mode whenever no uplink signals from radiotelephones are present. This may serve to reduce satellite receiver noise and, particularly important in hand-held embodiments relying on internal battery power, to reduce power consumption by the repeater.
[0231] The SOS ships, drone platforms, land towers, airborne devices, and satellites form a partial mesh network.
[0232] Mesh topology may be contrasted with conventional star/tree local network topologies in which the bridges/switches are directly linked to only a small subset of other bridges/switches, and the links between these infrastructure neighbors are hierarchical. While star-and-tree topologies are very well established, highly standardized and vendor-neutral, vendors of mesh network devices have not yet all agreed on common standards, and interoperability between devices from different vendors is not yet assured.
[0233] Mesh networks can relay messages using either a flooding technique or a routing technique. With routing, the message is propagated along a path by hopping from node to node until it reaches its destination. To ensure that all its paths are available, the network must allow for continuous connections and must reconfigure itself around broken paths, using self-healing algorithms such as Shortest Path Bridging. Self-healing allows a routing-based network to operate when a node breaks down or when a connection becomes unreliable. As a result, the network is typically quite reliable, as there is often more than one path between a source and a destination in the network. Although mostly used in wireless situations, this concept can also apply to wired networks and to software interaction.
[0234] A mesh network whose nodes are all connected to each other is a fully connected network. Fully connected wired networks have the advantages of security and reliability: problems in a cable affect only the two nodes attached to it. However, in such networks, the number of cables, and therefore the cost, goes up rapidly as the number of nodes increases.
[0235] The system of
[0249] As detailed above,
[0250] This system requires increasing distance, thus power, of data transmission from present land distances (limited by FCC broadcast power limits) to distances limited by tower height, stability, and antennae alignment. These factors combined with Affordability Analysis or economic analysis factors determine the optimal distance between towers. Once determined and integrated with maritime shipping data optimal transmission routes are established.
[0251] The optimal range and placement of equipment can be determined, and the information is relayed between freighters, stationary or movable drone platforms, blimps, among others.
[0252] Due to the ocean deployment, alignment of the transmitter and receiver devices are needed.
[0253] The system of
[0254] As shown in
[0259] GPS Units 1, 2, and 3 establish point A, the center of top circle GPS Units 4, 5, and establish the center point of bottom circle B.
[0260] RDF and FLIR allow clocking of the AXIS to another remotely located cylindrical axis using GPS units 7, 8, & 9 as top circle and GPS units 10, 11, & 12 as lower circle.
[0261] Angular variation or height delta between separate axes can be determined using locations of axes midpoints.
[0262] If axis or axes are rotating both speed of rotation and relative rate of rotation between different axes is determinable using the control system.
[0263] Two axes are established using GPS 1-6 and GPS 7-12 and leveled relative to the earth surface using gravity fluid level techniques. These multiple axes can be clocked relative to one another using RDF/radio transmitter or Laser/FLIR energy systems. Thus, multiple aligned circular axes can be determined with an O deg position relative to one another.
[0264] During operation, the system can establish a vertical or inclined cylindrical axis for a tube clocked to another vertical or inclined tube axis remotely located.
[0265] The GPS is a network of about 30 satellites orbiting the Earth at an altitude of 20,000 km. The system was originally developed by the US government for military navigation but now anyone with a GPS device, be it a Satnav, mobile phone or handheld GPS unit, can receive the radio signals that the satellites broadcast. From the platform, at least four GPS satellites are visible at any time. Each one transmits information about its position and the current time at regular intervals. These signals, travelling at the speed of light, are intercepted by the GPS receiver, which calculates how far away each satellite is based on how long it took for the messages to arrive. Once it has information on how far away at least three satellites are, the GPS receiver can pinpoint location using a process called trilateration. The more satellites there are above the horizon the more accurately your GPS unit can determine where the platform is.
[0266] GPS satellites have atomic clocks on board to keep accurate time. General and Special Relativity however predict that differences will appear between these clocks and an identical clock on Earth. General Relativity predicts that time will appear to run slower under stronger gravitational pullthe clocks on board the satellites will therefore seem to run faster than a clock on Earth. Furthermore, Special Relativity predicts that because the satellites' clocks are moving relative to a clock on Earth, they will appear to run slower. The whole GPS network has to make allowances for these effects.
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[0268] The shipboard towers would just have a simple hydraulic or pneumatic leveling system (with at least 3 cylinders) based on the GPS axis determination. Controllers can be used to actively move the energy emitter relative to the energy receiver to align the axis.
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[0270] The system of
[0271] The system can establish one or more axis/axes with orientation parallel or alternatively inclined to a radius originating from the center of earth. This is an improvement over current methods involve using surveying techniques that are cumbersome and time consuming or involve gyroscope or gyrocompass type tools/equipment. Additionally, the system can function on liquid surfaces such as lakes and oceans.
[0272] This system easily allows the creation of single or multiple clocked cylindrical axis/axes relative to a radius originating from the center of the earth or an axis/axes obliquely aligned from a point at the surface of the earth to another point elevated above the earth's surf ace. The system can also be used in systems that intersect the subsurface, surface and above surface atmosphere in contact with a fluid surface.
[0273] Preferably, the shortest curve between 3 points is a circle. Each circle has a center that is well defined by a midpoint of the diameter and having developed an upper and lower circle or plane, the midpoint lies on the line establishing the axis of the two circle centers and is determined by dividing the distance by two. The midpoint height (supplied by GPS) when compared to the midpoint height on the adjacent platforms determines the horizontal height delta between the adjacent drone platforms. In this manner, the angular relationship between two adjacent drone platforms relative to a horizontal tangent plane to the surface of the earth (ocean in this case can be determined and the information is then used to align the antennae refinement system of
[0274] The above system coupled with the elimination of FCC power restrictions on and near land allow the creation of an above ocean world wide data distribution network.
[0275]
[0276]
[0277] In the foregoing example, using six GPS units that provide Latitude and Longitude locations (not relying on height above sea level readings) a cylindrical axis can be established. Using additional GPS receivers creates the potential to develop additional axes. Combining a gravity fluid or liquid level system a controlled orientation either parallel or acutely aligned to the radius of the earth can be established. The system thus permits the establishment and alignment of a cylindrical axis over distance greater then methods currently available using other techniques.
[0278] Telecommunications antennae alignment is possible using this method or process. The system is particularly applicable to alignment on surfaces capable of movement such as lake, ocean, or fluid surfaces.
[0279] Construction or alignment of structures over distance is also easily accomplished using this technique. The system is applicable to all moving vehicles utilizing alignment-sensitive system elements such as military aircraft, commercial aircraft, armored tanks, helicopters, ships, aircraft carriers, submarines, spacecraft, missiles, and so forth. In addition, it applies to numerous instruments, sensors, radar, INS, FLIR, and gun sighting devices being only examples. Given the specific force vectors any of the known means, such as computer programs and other calculating methods, can be used to determine the misalignment.
[0280] In short, an Axis Development and Vertical Alignment Utilizing GPS Positioning and Fluid Leveling Techniques can be used that easily allows the creation of single or multiple clocked cylindrical axis relative to a radius originating from the center of the earth or an axis obliquely aligned from a point at the surface of the earth to another point elevated above the earth's surface.
[0281] ALSWOT is a system of systems for global internet connectivity that is remotely controlled and monitored and relocatable as needed, with stabilized towers, unfettered by FCC power output limits, that has further refinement of transmission and receiving equipment. ALSWOT thus provides competition and improvement over the old disrupt able technology of undersea cables. The ALSWOT can be leased for its tower height to shored based distributors as AMT leases tower height for land-based towers to customers.
[0282] The invention further provides methods and procedures performed by the structures, devices, apparatus, and systems described herein before, as well as other embodiments incorporating combinations and sub combinations of the structures highlighted above and described herein.
[0283] All publications including patents, pending patents and reports listed or mentioned in these publications and/or in this patent/invention are herein incorporated by reference to the same extent as if each publication or report, or patent or pending patent and/or references listed in these publications, reports, patents or pending patents were specifically and individually indicated to be incorporated by reference. The invention now being fully described, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the appended claims. In the drawings and specification, there have been disclosed typical embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.