Abstract: An electronically steerable phased array and switching network connected to an FMCW radar transceiver to enable a low-cost monopulse tracking system that covers a wide field of regard using electronic beam steering. In a first mode, beamformer integrated circuits (BFICs) at each element in the array are switched synchronously with transmit/receive (T/R) switches located at the subarray level. This allows the entire aperture to be switched between transmission and reception, enabling the FMCW radar transceiver to be operated in a pulsed configuration. In a second mode, a portion of the T/R switches at the subarray level and all of the connecting BFICs at the element level are fixed in either transmitting or receiving mode, allowing separate portions of the aperture to concurrently transmit or receive. The arrangement of transmitting and receiving subarrays can be dynamically reconfigured to allow for accurate bearing and azimuth estimation using alternating monopulse.

Abstract: A retrofit system applied to existing FMCW radars in order to convert them into pulsed linear frequency-modulated radars with the ability to dynamically switch between two pulsed modes and an FMCW mode based on the estimated range of a target. This retrofit also includes provisions for adaptively configuring chirp and sweep parameters to optimize range resolution. The result is a retrofit system capable of converting an FMCW radar into a dual pulsed mode radar with adaptive sweep configuration.

Abstract: An integrated radar circuit comprising: a first substrate, of a first semiconductor material, said first substrate comprising an integrated transmit and receive radar circuit; a second substrate, of a second semiconductor material, said second substrate comprising at least on through-substrate cavity having cavity walls; at least one discrete transistor chip, of a third semiconductor material, said at least one discrete transistor chip having chip walls and being held in said at least one through-substrate cavity by a metal filling extending from at least one cavity wall to at least one chip wall; a conductor on said second substrate, electrically connecting a portion of said integrated transmit and receive radar circuit to a discrete transistor on said at least one discrete transistor chip.

Abstract: An apparatus and method for orthogonal rotation of a radiation E-field polarization rely on a radiating element including an offset-ridge waveguide and a single-mode first ridge waveguide functionally adjacent to the offset-ridge waveguide.

Abstract: An apparatus and method for orthogonal rotation of a radiation E-field polarization rely on a radiating element including an offset-ridge waveguide and a single-mode first ridge waveguide functionally adjacent to the offset-ridge waveguide.

Abstract: An integrated radar circuit comprising: a first substrate, of a first semiconductor material, said first substrate comprising an integrated transmit and receive radar circuit; a second substrate, of a second semiconductor material, said second substrate comprising at least on through-substrate cavity having cavity walls; at least one discrete transistor chip, of a third semiconductor material, said at least one discrete transistor chip having chip walls and being held in said at least one through-substrate cavity by a metal filling extending from at least one cavity wall to at least one chip wall; a conductor on said second substrate, electrically connecting a portion of said integrated transmit and receive radar circuit to a discrete transistor on said at least one discrete transistor chip.

Abstract: A frequency-modulated continuous wave (FMCW) coded aperture radar (CAR) implemented on an integrated circuit (IC) to step through a range of frequencies in each sweep and a method of assembling the FMCW CAR implemented on an IC are described. The CAR implemented on the IC includes an antenna element to transmit or receive at a given time duration, a transmit channel to process a signal for transmission, the transmit channel including a transmit switch configured to change a state of a transmit phase shifter between two states based on a first code, and a receive channel to process a received signal, the receive channel including a receive switch configured to change a state of a receive phase shifter between two states based on a second code. A switch controller controls the first code and the second code and controls the first code to remain constant within the sweep.

Abstract: A radar system includes a traveling-wave imaging manifold (TIM) antenna including a waveguide with multiple paths configured such that adjacent ones of the multiple paths have different path lengths. The radar system also includes a processor configured to generate a transmit signal to be input at an opening of the waveguide or to process a reflection obtained from the opening of the waveguide.

Abstract: An RF circulator in combination with a RF integrated circuit, the RF integrated circuit having a plurality of RF waveguide or waveguide-like structures in or on the RF integrated circuit, the RF circulator comprising a disk of ferrite material disposed on a metallic material disposed on or in the RF integrated circuit, the disk of ferrite material extending away from the RF integrated circuit when disposed thereon, the metallic portion having a plurality of apertures therein adjacent the disk of ferrite material which, in use, are in electromagnetic communication with the disk of ferrite material and with the plurality of RF waveguide or waveguide-like structures, the disk of ferrite material being disposed in a metallic cavity.

Abstract: A radio frequency (RF) antenna array for an RF printed circuit board (RF-PCB) having a PCB ground layer includes an interposer assembly, conductive pillars, and load element. The interposer assembly includes a substrate, a ground layer defining one or more apertures, a dielectric layer, and a microstrip trace. The substrate is spaced apart from the RF-PCB. The interposer ground layer is deposited onto the substrate. The dielectric layer is deposited onto the interposer ground layer. The microstrip trace, positioned on the dielectric layer, receives and directs incident RF energy along the longitudinal axis. The pillars electrically connect the ground layers and structurally support the substrate, such that RF energy along the trace couples to the upper surface of the interposer assembly through the aperture(s). The load element connects in series to the microstrip trace at a distal/terminal end of the array.

Abstract: A radar system includes a traveling-wave imaging manifold (TIM) antenna including a waveguide with multiple paths configured such that adjacent ones of the multiple paths have different path lengths. The radar system also includes a processor configured to generate a transmit signal to be input at an opening of the waveguide or to process a reflection obtained from the opening of the waveguide.

Abstract: A radio frequency (RF) antenna array for an RF printed circuit board (RF-PCB) having a PCB ground layer includes an interposer assembly, conductive pillars, and load element. The interposer assembly includes a substrate, a ground layer defining one or more apertures, a dielectric layer, and a microstrip trace. The substrate is spaced apart from the RF-PCB. The interposer ground layer is deposited onto the substrate. The dielectric layer is deposited onto the interposer ground layer. The microstrip trace, positioned on the dielectric layer, receives and directs incident RF energy along the longitudinal axis. The pillars electrically connect the ground layers and structurally support the substrate, such that RF energy along the trace couples to the upper surface of the interposer assembly through the aperture(s). The load element connects in series to the microstrip trace at a distal/terminal end of the array.

Abstract: An RF circulator in combination with a RF integrated circuit, the RF integrated circuit having a plurality of RF waveguide or waveguide-like structures in or on the RF integrated circuit, the RF circulator comprising a disk of ferrite material disposed on a metallic material disposed on or in the RF integrated circuit, the disk of ferrite material extending away from the RF integrated circuit when disposed thereon, the metallic portion having a plurality of apertures therein adjacent the disk of ferrite material which, in use, are in electromagnetic communication with the disk of ferrite material and with the plurality of RF waveguide or waveguide-like structures, the disk of ferrite material being disposed in a metallic cavity.

Abstract: A method of and an apparatus for reducing noise in a non-Foster circuit having at least a pair of cross coupled transistor devices, each transistor device of the pair of cross coupled transistor devices having a pair of current carrying electrodes. The method and apparatus involves coupling inductors with each pair of the current carrying electrodes of each of the cross-coupled transistor devices in the non-Foster circuit, the inductors also being coupled with voltage and/or current sources associated with or coupled to the non-Foster circuit. The nominal values of the inductors are selected to provide a load asymmetry, so that the load inductor in the input side of the non-Foster circuit has a larger inductance than the load inductor at the output side of non-Foster circuit.

Abstract: A frequency-modulated continuous wave (FMCW) coded aperture radar (CAR) implemented on an integrated circuit (IC) to step through a range of frequencies in each sweep and a method of assembling the FMCW CAR implemented on an IC are described. The CAR implemented on the IC includes an antenna element to transmit or receive at a given time duration, a transmit channel to process a signal for transmission, the transmit channel including a transmit switch configured to change a state of a transmit phase shifter between two states based on a first code, and a receive channel to process a received signal, the receive channel in including a receive switch configured to change a state of a receive phase shifter between two states based on a second code. A switch controller controls the first code and the second code and controls the first code to remain constant within the sweep.

Abstract: An integrated circuit (IC) of a frequency-modulated continuous wave (FMCW) coded aperture radar (CAR) configured to step through a range of frequencies in each sweep and a method of assembling the FMCW CAR are described. The IC includes an antenna element to transmit and receive at a given time duration, a transmit channel to process a signal for transmission, the transmit channel including a transmit switch to change a state of a transmit phase shifter between two states based on a first code, and a receive channel to process a received signal, the receive channel including a receive switch to change a state of a receive phase shifter between two states based on a second code. The IC also includes a switch controller to control the first code and the second code, wherein the switch controller controls the first code to remain constant within the sweep.

Abstract: A method and apparatus for reducing noise in a coded aperture radar system, the coded aperture radar system transmitting signals which occur in sweeps, with K sweeps utilized to cover field of view of the coded aperture radar system and Q frequency shifts or steps occurring each sweep thereof. An array of N antenna elements is provided, the array of antenna elements each having an associated two state modulator coupled therewith. Energy received at the array is modulated according to a sequence of multibit codes, the number of codes in the sequence of codes comprising at least K times Q times N, thereby reducing noise in the coded aperture radar system compared to a coded aperture radar system radar system having fewer than K times Q times N codes in its sequence of multibit codes.

Abstract: A traveling wave detector and method of traveling wave signal detection employ a plurality of detector diodes connected according to different polarities with respect to adjacent ones of the detector diodes. The traveling wave detector includes a transmission line having an input end and a terminal end and the plurality of detector diodes connected as stated above and spaced apart along the transmission line. The traveling wave detector further includes a plurality of direct current (DC) blocks to define a series conduction path. The method of traveling wave signal detection includes rectifying a received incident signal using the traveling wave detector to produce a video signal at each of the detector diodes and summing the video signals along the series conduction path to produce an output video signal.

Abstract: A radar system in which Coded Aperture Radar processing is performed on received radar signals reflected by one or more objects in a field of view which reflect a transmitted signal which covers a field of view with K sweeps and each sweep including Q frequency changes. For Type II CAR, the transmitted signal also includes N modulated codes per frequency step. The received radar signals are modulated by a plurality of binary modulators the results of which are applied to a mixer. The output of the mixer, for one acquisition results in a set of Q·K (for Type I CAR) or Q·K·N (for Type II CAR) complex data samples, is distributed among a number of digital channels, each corresponding to a desired beam direction. For each channel, the complex digital samples are multiplied, sample by sample, by a complex signal mask that is different for each channel.

Abstract: An antenna array containing two or more radiating elements, with nearest neighbor radiating elements connected together with a non-Foster circuit at terminals of the radiating elements such that mutual reactance of the elements is reduced over a wider bandwidth than which would be obtained if the non-Foster circuits were omitted.