Abstract: In the disclosed optically-fed transmitting phased-array architecture, transmitting signals are converted between the electrical domain and the optical domain by using electro-optic (EO) modulators and photodiodes. RF signal(s) generated from a relatively low frequency source modulate an optical carrier signal. This modulated optical signal can be remotely imparted to photodiodes via optical fibers. Desired RF signals may be recovered by photo-mixing at the photodiodes whose wired RF outputs are then transmitted to radiating elements of the antennas. The antenna array may generate a physical RF beam that transmits an RF signal that is focused on one or more selectable locations. Multiple RF beams may be simultaneously generated, each RF beam being capable of being directed to focus on a unique location or set of locations.

Abstract: A system and method reconstructs RF sources in k-space by utilizing interference between RF signals detected by an array of antennas. The system and method may include detecting an RF interference pattern resulting from interference between RF signals in an RF coupler, where the RF signals are detected by the antennas and provided to the RF coupler by RF waveguides. The RF waveguides may have unequal RF path lengths. K-space information of the RF sources may be reconstructed from the detected RF interference pattern using known tomography reconstruction methods.

Abstract: Traveling-wave directional filters (DFs) with multiple coupling slots are disclosed. A traveling-wave directional filter may include two terminating conductive strips in a top circuit layer of a substrate, a loop resonator in a bottom layer of a substrate, and a shared ground plane. Coupling slots in the ground plane may couple the conductive strips via the loop resonator.

Abstract: An optical imaging system and method that reconstructs RF sources in k-space by utilizing interference amongst modulated optical beams. The system and method involves recording with photodetectors the interference pattern produced by RF-modulated optical beams conveyed by optical fibers having unequal lengths. The photodetectors record the interference, and computational analysis using known tomography reconstruction methods is performed to reconstruct the RF sources in k-space.

Abstract: A system and method reconstructs RF sources in k-space by utilizing interference between RF signals detected by an array of antennas. The system and method may include detecting an RF interference pattern resulting from interference between RF signals in an RF coupler, where the RF signals are detected by the antennas and provided to the RF coupler by RF waveguides. The RF waveguides may have unequal RF path lengths. K-space information of the RF sources may be reconstructed from the detected RF interference pattern using known tomography reconstruction methods.

Abstract: Disclosed herein is a swappable modular-based radiofrequency (RF) frontend that is reconfigurable to form transmitting (TX) and receiving (RX) phased array systems for diverse applications. Such swappable RF frontend may be used with unique spatial and spectral optical processing of complex RF signals over an ultra-wide frequency band. The swappable RF front end may be used in conjunction with an optically upconverted imaging receiver and/or in conjunction with optically addressed phased array technologies transmitters.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: An optical imaging system and method that reconstructs RF sources in k-space by utilizing interference amongst modulated optical beams. The system and method involves recording with photodetectors the interference pattern produced by RF-modulated optical beams conveyed by optical fibers having unequal lengths. The photodetectors record the interference, and computational analysis using known tomography reconstruction methods is performed to reconstruct the RF sources in k-space.

Abstract: An optical imaging system and method that reconstructs RF sources in k-space by utilizing interference amongst modulated optical beams. The system and method involves recording with photodetectors the interference pattern produced by RF-modulated optical beams conveyed by optical fibers having unequal lengths. The photodetectors record the interference, and computational analysis using known tomography reconstruction methods is performed to reconstruct the RF sources in k-space.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: A system and method reconstructs RF sources in k-space by utilizing interference between RF signals detected by an array of antennas. The system and method may include detecting an RF interference pattern resulting from interference between RF signals in an RF coupler, where the RF signals are detected by the antennas and provided to the RF coupler by RF waveguides. The RF waveguides may have unequal RF path lengths. K-space information of the RF sources may be reconstructed from the detected RF interference pattern using known tomography reconstruction methods.

Abstract: This disclosure is directed to two-dimensional conformal optically-fed phased arrays and methods for manufacturing the same. The method includes providing a wafer substrate, depositing a first cladding layer on the wafer substrate, and depositing a core layer on the first cladding layer. The method further includes photolithographically patterning the core layer to provide a plurality of optical waveguide cores, and depositing a second cladding layer on the core layer to cover the plurality of optical waveguide cores to provide a plurality of optical waveguides. In addition, the method includes forming a plurality of antennas on the second cladding layer, each antenna of the plurality of antennas located near a termination of a corresponding optical waveguide of the plurality of optical waveguides, and providing a plurality of photodiodes on the second cladding layer, each photodiode of the plurality of photodiodes connected to a corresponding antenna.

Abstract: Traveling-wave directional filters (DFs) with multiple coupling slots are disclosed. A traveling-wave directional filter may include two terminating conductive strips in a top circuit layer of a substrate, a loop resonator in a bottom layer of a substrate, and a shared ground plane. Coupling slots in the ground plane may couple the conductive strips via the loop resonator.

Abstract: An optical imaging system and method that reconstructs RF sources in k-space by utilizing interference amongst modulated optical beams. The system and method involves recording with photodetectors the interference pattern produced by RF-modulated optical beams conveyed by optical fibers having unequal lengths. The photodetectors record the interference, and computational analysis using known tomography reconstruction methods is performed to reconstruct the RF sources in k-space.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: According to embodiments of the invention, the design and fabrication of a binary superimposed grating (BSG) results in better performing devices that may be fabricated using existing technology. The fabrication process includes forming grating features based upon repeating features of the desired superposition function. The design process also relaxes the processing requirement for equivalently performing devices.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: An optical feed network for a phased-array antenna may comprise a phase-based feed network that may include electro-optical phase shifting.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: An optically-fed tightly-coupled array (TCA) antenna comprises a plurality of photodiodes and antennas. Each photodiode may receive an optical signal from an optical fiber and convert the optical signal into an RF driving signal to drive a corresponding antenna to which it is connected. Each photodiode may be connected to the antenna. In some examples, the TCA is capable of ultra-wideband operation ranging from 2-12 GHz and wide beam-steering capability up to 40° from the broadside. Inductance peaking and resistance matching may be employed.