Abstract: An embodiment of an electronically scanned array antenna includes an array of radiative elements having an array height. A plurality of separate subarrays of the radiative elements include a first row comprising a first plurality of subarrays, wherein subarrays of the first plurality of subarrays are horizontally non-overlapping with one another, and a second row comprising a second plurality of subarrays. The subarrays of the second row are arranged vertically adjacent to the subarrays of the first row, wherein subarrays of the second plurality of subarrays are horizontally non-overlapping with one another. The radiative elements of the separate subarrays are not shared with any other subarray. The subarrays of the radiative elements have subarray heights which are smaller than the array height.

Abstract: An embodiment of an electronically scanned array antenna includes an array of radiative elements having an array height. A plurality of separate subarrays of the radiative elements include a first row comprising a first plurality of subarrays, wherein subarrays of the first plurality of subarrays are horizontally non-overlapping with one another, and a second row comprising a second plurality of subarrays. The subarrays of the second row are arranged vertically adjacent to the subarrays of the first row, wherein subarrays of the second plurality of subarrays are horizontally non-overlapping with one another. The radiative elements of the separate subarrays are not shared with any other subarray. The subarrays of the radiative elements have subarray heights which are smaller than the array height.

Abstract: A process for collecting phase and amplitude calibration data for an active array system without the use of external sensors. The relative phase and amplitudes of adjacent T/R modules are determined when viewed through the entire array system. The calibration process involves collecting and storing these phases and amplitudes for future use. A pulse-to-pulse phase or amplitude modulation mode is employed. An element is commanded into this mode to separate its signal (in frequency) from competing signals and leakages from the surrounding modules. A T/R inversion command allows for a single element to be switched to a transmit state while the remainder of the array is in the receive state. This provides for a reference signal during receive calibration, and for single module testing during transmit calibration.

Abstract: A technique for phase-up of array antennas of regularly spaced lattice orientation, without the use of a nearfield or farfield range. The technique uses mutual coupling and/or reflections to provide a signal from one element to its neighbors. This signal provides a reference to allow for elements to be phased with respect to each other. After the first stage of the process is completed, the array is phased-up into, at most, four interleaved lattices. These interleaved lattices are then phased with respect to each other, thus completing the phase-up process.

Abstract: An RF drive leveling adjustment method using transmit amplitude adjustment range for use with active phased array antenna systems. Relative RF measurements of transmit amplitude adjustment range of an active array antenna or selected elements or sets of elements of the antenna are used to determine correction factors for RF drive levels of RF drive amplifier(s) used by transmit modules of the active array antenna. The method comprises the following steps. The first step comprises calibrating the transmit RF drive amplifiers of an active array antenna for a predetermined transmit duty factor and pulse repetition frequency. The second step comprises measuring relative RF measurements of transmit amplitude adjustment range of the transmit module. The third step comprises determining correction factors for RF drive levels of the transmit RF drive amplifiers. The fourth step comprises adjusting the RF drive level of the transmit RF drive amplifiers using the correction factors.

Abstract: Variable array thinning to achieve efficient radar pulse shaping for advanced radar waveforms such as pulse burst or monopulse doppler. At the beginning of the pulse, only a few elements, spread out over the array, are turned on. The effective amplitude can be controlled with precision because each element is either off or at saturation. High efficiency is maintained because the off-state of each element is long enough so that prime power is not consumed.

Abstract: The corporate feed network employs light emitting opto-electronic components, such as laser diodes (12), connected together in a string (14) for distributing RF, microwave, MMW, digital signals, and pulse modulated light. Each diode provides two ports or facets which are coupled to optical fibers (16, 18) to connect to an active phased array antenna, for example. The diodes are selected in number and impedance to provide a good wideband impedance match to the RF/microwave/MMW/digital driving source. Multiple series strings of diodes may be employed, connected in parallel for larger corporate feed structures.