A man-portable phased array ISR system includes a multilayer panel. A first panel layer includes a subarray layer having a plurality of sensors for detecting and receiving radiofrequency information. A second panel layer includes a digital data storage system to digitize, record and store the radiofrequency information. A third panel layer includes a command and communication link. A fourth panel layer includes a nanoparticle ultra-capacitor energy storage system adapted to provide power to the subarray, to the digital data storage system and to the command and communication link. The plurality of sensors may be receive-only sensors for radio-frequency data collection. The first panel layer may include integral beamforming systems having a predetermined frequency range for transmit an receive radar signal formation and data collection.

Not applicable.

FIELD OF THE INVENTION

The invention relates generally to phased arrays, and more particularly to lightweight, man-portable, wideband phased array ISR systems.

BACKGROUND OF THE INVENTION

Successful missile defense systems require accurate observability of threats in flight. Additionally, the observability of threats in flight includes one or more of the steps of target acquisition, tracking, sensor fusion, discrimination, aim-point selection, and kill assessment. Threat observability typically depends on large, fixed phased array systems. However, the large, fixed phased array systems are expensive to implement and maintain, and failure of one system may lead to gaps in threat observability. Further, during military engagements, threat observability may be primarily a local phenomenon. Depending upon location, threat observability may not be available from a large, fixed phased array system.

Portable phased array intelligence, surveillance, and reconnaissance (ISR) collection systems have been implemented. However, “portable” phased arrays range in size from units weighing hundreds of pounds designed to be carried and set up by one or more persons to units weighing thousands of pounds designed to be integrally mounted only on mobile vehicles. Additionally, known portable phased array ISR systems require external power supplies such as generators, fuel cells, or the like, which are large and must be transported with the portable phased array ISR system. Known portable phased array ISR systems further include external command and control modules, often larger than the antenna array itself, that are interconnected to the ISR phased array antenna, either directly in substantially the same package as the array or via cables to remote locations.

Accordingly, there is a need for a phased array ISR system that is capable of being carried and deployed by a single individual that is self-contained, has a small form factor, and includes an integral beamforming system, integral command and control, and integral power storage and supply.

SUMMARY OF THE INVENTION

Concordant and consistent with the present invention, a lightweight, man-portable, wideband, phased array ISR system has surprisingly been discovered.

The phased array ISR system includes a multilayer panel. A first panel layer includes a subarray layer having a plurality of sensors for detecting and receiving radiofrequency information. A second panel layer includes a digital data storage system to digitize, record and store the radiofrequency information. A third panel layer includes a command and communication link. A fourth panel layer includes a nanoparticle ultra-capacitor energy storage system adapted to provide power to the subarray, to the digital data storage system and to the command and communication link. The plurality of sensors may be receive-only sensors for radio-frequency data collection. The first panel layer may include integral beamforming systems having a predetermined frequency range for transmit and receive radar signal formation and data collection.

In one embodiment, the phased array system includes fourth panel layer having a command and communication link for data transmission and remote system management. The command and communication link may be wireless or wired. The command and communication link may also be utilized to link two or more subarrays together to create diversity of orientation to develop more coverage, or to create a larger, more sensitive aperture, or to deliver more precise beam pointing in elevation or azimuth. A GPS locator may also be arranged as a fifth panel layer.

In another embodiment, the first layer may include integral beamforming systems for beam formation within one of an L-band, an S-band, a C-band, an X-band, a Ku-band, a K-band, or a Ka-band radar frequency range. In another embodiment, a fully functional bistatic active electronically scanned phased array system including digital data storage, an advanced power system and a GPS locator is integrated into a single subarray panel that has a thin profile and a scalable form factor.

DETAILED DESCRIPTION OF THE INVENTION

As shown inFIG. 1, an integrated phased array system10is constructed from multiple circuit boards arranged in layers. A subarray layer12is formed using known methods and commercial off the shelf components, including multilayer printed circuit board technology, advanced beamforming radiofrequency integrated circuitry, miniaturized filters, and field programmable gate array technology. The subarray layer12includes an array of antenna elements14arranged in a predetermined lattice structure on the outermost surface16of the subarray layer12. The antenna elements14inFIG. 1are shown as circular elements arranged in a triangular lattice structure18mounted on the surface16having a rectangular outer perimeter20. It is understood, however, that the lattice structure and the shape of individual antenna elements may vary as desired. As non-limiting examples, the outer surface perimeter20may have a hexagon or octagon shape as desired.

The subarray layer12integrates all of the electrical circuits required to implement a fully functional active electronically scanned phased array into a single panel that has a thin profile and a predetermined form factor. The subarray layer12may be designed as a receive-only subarray to detect and acquire signals within a predetermined frequency band. The subarray layer12may also be designed to include a beamforming system within the desired frequency band to enable transmit and receive radar scanning and detection. Favorable results have been demonstrated wherein the subarray layer12operating within the S-band frequency range between 2.2 and 2.4 GHz has delivered a plurality of steerable beams with dual polarization for long range tracking of multiple targets, wherein the subarray thickness t1is less than about 0.2 inches. Favorable results have also been demonstrated wherein the subarray layer12operating in the cell phone bands between 1992 to 2170 MHz in both transmit and receive mode has been constructed having a subarray thickness t1of less than about 0.675 inches. Favorable results have also been demonstrated in the X-band frequency range between 8.0 and 12.0 GHz wherein the subarray layer12includes 256 dual polarization antenna elements14arranged in a triangular lattice structure having a thickness t1less than about 0.5 inches. It is understood that the sublayer12may be constructed to operate in other radar frequency bands, including but not limited to L-band, C-band, Ku-band, K-band and Ka-band.

When used as either a receive-only antenna or as a transmit and receive antenna, the subarray12electronically scans in both azimuth and elevation across the predetermined frequency band, and acquires signals of interest. Once a signal is acquired, the subarray12locks onto the signal for data collection. The phased array system10tracks, digitizes, and records the signal of interest as signal digital data. The signal digital data is stored in a data storage layer22for later extraction, or it may be transmitted by a command and communication link layer24. Both the data storage layer22and the command and communication link layer24may optionally have the same or smaller form factor as the subarray12, defined by the shape of the perimeter20of the subarray layer12.

The signal digital data derived from the receive signal may be transmitted in real time, or it may be temporarily stored and transmitted manually, upon command, or after a predetermined time delay. The digital storage layer22may include any known digital data storage method, including solid state storage and may also include any software instructions or programs required to control the system10, including control of the antenna elements14, the digital storage layer22, and the command and communication link layer24.

The command and communication link layer24may be controlled automatically through implementation of internal control software stored on the digital storage layer22. Alternatively, the command and communication link layer24may be remotely controlled, and may include wireless data extraction, instruction delivery, and retrieval. The command and communication link layer24may also be adapted to transmit information on any suitable wiring, such as twisted pair or coaxial cable for example. No provision is made within the command and communication link layer24to analyze or process data beyond collection and storage thereof. Because the system does not include data processing or analysis, the power requirements of the system are minimized, while maximizing the data collection time.

Optionally, a GPS module28may be included within the system10to allow the system10to associate collected data with positional and temporal information for data fusion of multiple apertures. In this way, the location of the system10, the relative location, or bearing of the tracked data and a time tag may be stored as system digital data available for extraction and later analysis.

Power is provided to the system10, including to the subarray12and the data storage layer22, by one or more energy storage layers30having substantially the same form factor as the subarray layer12, defined by the shape of the perimeter20of the subarray layer12. The energy storage layer30is formed as a nanoparticle ultra-capacitor as described in U.S. Patent Application Publication No. US2008/0316678, incorporated herein by reference in its entirety. The energy storage layer30has a higher storage density and lower weight than conventional lead acid batteries, and may include sublayers of multiple cells (not shown) electrically connected in parallel to form a cell pack arranged as the energy storage layer30. As described in U.S. Patent Publication No. US2008/0316678, by electrically connecting the multiple cells in parallel, each cell provides a lower current with lower cell resistance, resulting in thinner cells having higher energy storage efficiency. Thinner cells reduce both weight and cost. Because of the lower power requirements of the system10, in combination with the higher energy storage density of the energy storage layer30, the system10is capable of data collection in either receive-only or transmit and receive modes of operation for extended periods of time.

Because the system10is manufactured in successive layers, each layer may be optimized for weight and performance for a given frequency band. When optimized for weight, the system10may be formed so that the entire system weight is less than about 75 pounds when the subarray layer12has a form factor of a square about one meter on each side and a thickness t1of less than about one inch, making the system10capable of being carried and implemented by a single individual. Additionally, a single individual may transport and rapidly implement multiple systems as a larger array.

Because of the small size and weight of each system10, multiple phased array systems10may be carried by a single vehicle and arranged by a single individual into a multiple aperture phased array system50, shown in FIG.2, where each system10is independently tasked for data collection. For example, as shown inFIG. 2, six phased array ISR systems10A-10F are arranged in a hexagonal arrangement diversity of orientation to develop full azimuth coverage when each system10A-10F is independently tasked. Alternatively, the multiple systems10A-10F shown inFIG. 2are scalable, and may be interconnected wirelessly or directly linked together through the command and communication link layer26A-26F of each respective individual system10A-10F. In particular, the command and communication link layer26A-26F of each respective individual system10A-10F is capable of interfacing and linking with one or more other systems. As a non-limiting example, the wireless command and communication link26A of system10A may interface and link with the command and communication link26F of the system10F to create a single aperture, wherein the sensors14A and14F are controlled together. In this way, by coupling multiple systems10A-10F together, independently or dependently, larger phased array systems50may be designed and arranged to form larger phased array radar apertures, or may be arranged to provide diversity of orientation to develop more signal coverage over azimuth or elevation. Arranging multiple subarray systems12over a larger area or spatial distribution and with a diversity of orientation provides coordinated data collection, while larger aperture size allows for an improved sensor performance as measured by a ratio of antenna gain divided by the system temperature (higher G/T), leading to greater sensitivity for detecting and receiving weak or low-power signals. Larger apertures also enable narrower steerable beams for special collection missions. As a result, the small, integrated phased array system10of the present disclosure may be easily tailored to fit many collection and monitoring missions. In particular, each system10may be tasked for individual data collection in one scenario, and also may be selectively linked to additional systems10to meet different collection scenarios. The system10therefore provides an extremely flexible data collection system capable of multiple configurations suitable for multiple different deployment scenarios.

Because each system is modular, integrated, and independently controllable, a single operator may deploy, command, and control a plurality of man-portable mobile antennas, each working either independently or in combination with one or more systems10. Further, the control of each subarray10may be remote through a wireless or wired command and control communication module26. Finally, the integral energy storage layer30ensures that power is available directly to the subarray12without significantly affecting the package size or weight.