Abstract: A method for identifying performance bounds of a transmit-receive (T/R) module over a bandwidth ƒb when connected to an antenna, a transmitter, and a receiver all with known reflectance within the bandwidth ƒb; measuring a raw T/R module point representing isolation and insertion loss of the T/R module when connected to the antenna, the transmitter, and the receiver without a matching circuit; plotting the raw T/R module point on a performance image graph; using a mathematical representation of a multiport matching circuit that contains no gyrators and comprises a fixed number of capacitors and inductors to approximate a Pareto front comprised of a plurality of Pareto points; and connecting each Pareto point to the raw T/R module point on the performance image graph such that the performance image becomes a visual representation of the performance bounds of a class of multiport matching circuits having capacitors and inductors.

Abstract: An antenna comprising: a driven element; an input feed coupled to the driven element wherein the input feed is configured to be connected to a receiver; a non-Foster circuit having a negative impedance, wherein the non-Foster circuit is configured to actively load the antenna at a location on the antenna other than at the input feed; and wherein the antenna fits within an imaginary sphere having a radius a, and wherein the product ka is less than 0.5, where k is a wave number.

Abstract: A method for deploying a lightweight, flexible Faraday cage around a device can include the step of directing the conductive fluid flow in a manner that causes a shroud to form over the device. In some embodiments, a flexible material such as canvas can be deployed over the device and the conductive fluid can be sprayed onto the flexible material to form the shroud. In other embodiments, a plurality of nozzles can be placed around the perimeter of the device, and the nozzles can be directed at a predetermined point over the device. The streams can meet at the predetermined point, collide and thereby provide the conductive shroud for the device. The shroud can have a skin depth, which can be chosen according to the desired frequency of electromagnetic radiation to be blocked, typically from one to one hundred millimeters (1-100 mm).

Abstract: A method for deploying a lightweight, flexible Faraday cage around a device can include the step of directing the conductive fluid flow in a manner that causes a shroud to form over the device. In some embodiments, a flexible material such as canvas can be deployed over the device and the conductive fluid can be sprayed onto the flexible material to form the shroud. In other embodiments, a plurality of nozzles can be placed around the perimeter of the device, and the nozzles can be directed at a predetermined point over the device. The streams can meet at the predetermined point, collide and thereby provide the conductive shroud for the device. The shroud can have a skin depth, which can be chosen according to the desired frequency of electromagnetic radiation to be blocked, typically from one to one hundred millimeters (1-100 mm).

Abstract: A method for deploying a lightweight, flexible Faraday cage around a device can include the step of directing the conductive fluid flow in a manner that causes a shroud to form over the device. In some embodiments, a flexible material such as canvas can be deployed over the device and the conductive fluid can be sprayed onto the flexible material to form the shroud. In other embodiments, a plurality of nozzles can be placed around the perimeter of the device, and the nozzles can be directed at a predetermined point over the device. The streams can meet at the predetermined point, collide and thereby provide the conductive shroud for the device. The shroud can have a thickness, which can be chosen according to the desired frequency of electromagnetic radiation to be blocked, typically from one to one hundred millimeters (1-100 mm).

Abstract: An antenna comprising: a driven element; an input feed coupled to the driven element wherein the input feed is configured to be connected to a receiver; a non-Foster circuit having a negative impedance, wherein the non-Foster circuit is configured to actively load the antenna at a location on the antenna other than at the input feed; and wherein the antenna may be contained within an imaginary sphere having a radius a, and wherein the product ka is less than 0.5, where k is a wave number.

Abstract: A system includes an input multi-level channelizer, an output multi-level channelizer, and more than one amplifiers connected between the input and output channelizers. The input and output channelizers cover an operating frequency band. Each level of the input multi-level channelizer comprises a plurality of input channels, which may be bandpass filters, and may be grouped into input sub-channelizers. Each successive level of the input multi-level channelizer is configured to divide the incoming signals into smaller frequency bands. Each level of the output multi-level channelizer comprises a plurality of output channels, which may be bandpass filters, and may be grouped into output sub-channelizers. Each successive level of the output multi-level channelizer is configured to combine the incoming signals into larger frequency bands. The signal output from the output multi-level channelizer represents a filtered version of the signal input into the input multi-level channelizer.

Abstract: A system includes a first circulator, a second circulator connected to the first circulator and a load, a third circulator connected to the second circulator, and a filter connected between the first and third circulators. The filter modifies the phase and amplitude of a first signal from the first circulator to produce a modified first signal. The modified first signal amplitude may be equal to the amplitude of a second signal from the second circulator. The phase of the modified first signal is about 180 degrees out of phase with the second signal phase. The third circulator circulates the modified first signal towards the second circulator. The first signal comprises a coupled signal from the first circulator. The second signal comprises a signal reflected from the load and a coupled signal from the second circulator. The filter may be a passive network having lumped, distributed, and resistive elements.

Abstract: A system includes more than one subsystem, each subsystem operating within a different subsystem frequency range, the subsystems comprising a circulator having three or more circulator ports and a direction of circulation, the circulator operating within a specific frequency range of the subsystem frequency range, and a filter, such as a bandpass filter, connected to at least one of the circulator ports. The filters each define a subsystem port and operate within the specific frequency range. Each subsystem port has a port index determined by the direction of circulation of the circulator within the subsystem. Each subsystem port has a specific port index that is connected to a common port having the specific port index. At least one of the circulator ports may be terminated to a matched load. Each subsystem circulator may comprise at least three circulator ports, with a filter connected to each of the circulator ports.