This disclosure is directed to techniques to improve the mechanical reliability and strength of slot array antennae created using printed circuit board (PCB) technology. In some examples, a multi-layer PCB may have a limit on the length and width dimensions. Therefore, a larger slot array antenna may require two or more PCBs to create the full size of the antenna. This disclosure describes techniques to securely connect the two or more PCBs to withstand environments where the slot array antenna may be placed under mechanical stress, such as vibration. A PCB based antenna may define the walls of radiating waveguides with vias between the layers of the PCB. Mechanical fasteners may pass through some of the existing vias to secure the PCB to a support structure, such as a feeding waveguide, as well as to secure one PCB to other PCBs.

A liquid crystal cell includes TFT substrate including a first dielectric substrate, TFTs supported by the first dielectric substrate, and patch electrodes electrically connected to the TFTs, a slot substrate including a second dielectric substrate and a slot electrode including slots and supported by the second dielectric substrate, and a liquid crystal layer sandwiched between the TFT substrate and the slot substrate that are disposed such that the patch electrodes and the slot electrode face each other. Liquid crystal molecules included in the liquid crystal layer are oriented in all azimuthal angle directions in a state in which voltage is not applied between the patch electrodes and the slot electrode.

A liquid crystal cell includes TFT substrate including a first dielectric substrate, TFTs supported by the first dielectric substrate, and patch electrodes electrically connected to the TFTs, a slot substrate including a second dielectric substrate and a slot electrode including slots and supported by the second dielectric substrate, and a liquid crystal layer sandwiched between the TFT substrate and the slot substrate that are disposed such that the patch electrodes and the slot electrode face each other. Liquid crystal molecules included in the liquid crystal layer are oriented in all azimuthal angle directions in a state in which voltage is not applied between the patch electrodes and the slot electrode.

A TFT substrate includes TFTs, patch electrodes formed in a patch metal layer, and gate connection wiring lines formed in a gate metal layer. The patch metal layer includes: a first portion having a layered structure including a lower metal layer containing a refractory metal and an upper metal layer containing Cu, Al, or Ag; and a second portion including the lower metal layer and not including the upper metal layer. The first portion includes the patch electrode, and the second portion includes a first patch connection section electrically connecting a source bus line to the gate connection wiring line. The first patch connection section is in contact with the source bus line in a first opening provided in a first insulating layer, and is in contact with the gate connection wiring line in a second opening provided in a gate insulating layer and the first insulating layer.

A TFT substrate includes TFTs, patch electrodes formed in a patch metal layer, and gate connection wiring lines formed in a gate metal layer. The patch metal layer includes: a first portion having a layered structure including a lower metal layer containing a refractory metal and an upper metal layer containing Cu, Al, or Ag; and a second portion including the lower metal layer and not including the upper metal layer. The first portion includes the patch electrode, and the second portion includes a first patch connection section electrically connecting a source bus line to the gate connection wiring line. The first patch connection section is in contact with the source bus line in a first opening provided in a first insulating layer, and is in contact with the gate connection wiring line in a second opening provided in a gate insulating layer and the first insulating layer.

A method for arrangement of leaky coaxial cables applied to a strip-shaped elongated area, includes: reducing a quantitative radiation performance of initial ends of the leaky coaxial cable combination structures of two areas symmetrically arranged with respect to a central area in a length direction of the strip-shaped elongated area to ensure a small transmission loss, on the premise of ensuring that a comprehensive loss of a link tail end of the leaky coaxial cable is constant; and reducing an appropriate transmission loss of tail ends of the leaky coaxial cable combination structures of the two areas at the central area to increase the radiation performance.

A waveguide antenna (200) is disclosed, comprising: a first plurality (220) of slots (222,224), for producing a beam having a first radiation pattern (301) at a first resonant frequency (f1); and a second plurality (230) of slots (232, 234), for producing a beam having a second radiation pattern (302) at a second resonant frequency (f2). A method of operation of the waveguide antenna (200) is also disclosed, comprising: operating the transceiver at a first frequency (f1) to detect objects in a first field of view; and operating the transceiver at a second frequency (fa) to detect objects in a second field of view

The radar system includes a split-block assembly comprising a first portion and a second portion. The first portion and the second portion form a seam, where the first portion has a top side opposite the seam and the second portion has a bottom side opposite the seam. The system includes at least one port located on a bottom side of the second portion. Additionally, the system includes radiating elements located on the top side of the first portion, wherein the radiating elements are arranged in a plurality of arrays. Yet further, the system includes a set of waveguides in the split-block assembly configured to couple each array to at least one port. Furthermore, the split-block assembly is made from a polymer and where at least the set of waveguides, the at least one port, and the plurality of radiating elements include metal on a surface of the polymer.

The radar system includes a split-block assembly comprising a first portion and a second portion. The first portion and the second portion form a seam, where the first portion has a top side opposite the seam and the second portion has a bottom side opposite the seam. The system includes at least one port located on a bottom side of the second portion. Additionally, the system includes radiating elements located on the top side of the first portion, wherein the radiating elements are arranged in a plurality of arrays. Yet further, the system includes a set of waveguides in the split-block assembly configured to couple each array to at least one port. Furthermore, the split-block assembly is made from a polymer and where at least the set of waveguides, the at least one port, and the plurality of radiating elements include metal on a surface of the polymer.

An eLORAN receiver may include an antenna and eLORAN receiver circuitry coupled to the antenna. The antenna may have a ferromagnetic core including a ferromagnetic medial portion and ferromagnetic arms extending outwardly, and a respective electrically conductive layer surrounding each of the ferromagnetic arms and having a slot.