Abstract: A single-layer substrate integrated directive broadside beam leaky-wave antenna is provided. Opposite ends of a leaky-wave structure are fed with anti-phase versions of a common signal, resulting in broadside frequencies being set apart from the open stopband. To achieve this, the common signal can be split into two equal length paths, one including a perfect electrical conductor (PEC) reflector and the other including a perfect magnetic conductor (PMC) reflector. Alternatively, the common signal can be split into two paths which differ in length by a half wavelength. A power splitter and feed horns can be used in the respective paths. The leaky-wave structure may have transverse slots which increase in width toward a midpoint of the structure. The antenna can be formed in a single planar portion of a lithographic structure, for example by patterning an upper conductive layer thereof.

Abstract: Microwave circulators are an essentially component in many microwave systems and whilst the waveguide technologies they are implemented in have evolved their design today still employs procedures that are typically approximate and have no regular approach, which in many instances is through dependence on empirical equations or considered a trade secret that gives an edge to commercial suppliers of microwave and RF circulators. The result is expensive isolators where high performance is required as they are merely selected out or require manual tuning. Further, for broadband systems, designer's resort to dividing into sub-bands deploying multiple narrower band circulators. Accordingly, the inventors present a design methodology based on an accurate closed form solution allowing the selection of suitable ferrite specifications for the required operating bandwidth as well as calculating the ferrite disc impedance allowing the necessary matching network to be designed and the circulator design completed.

Abstract: Ridge Gap Waveguide (RGW) has emerged as a preferred waveguide technology for millimeter-wave frequencies. Microwave power splitters and switches represent important components for routing microwave signals and/or splitting a microwave signal into equal or unequal portions. To date, solutions have typically employed MEMS phase shifters, MEMS reflective loads, etc. or monolithic microwave integrated circuits to replace traditional electromechanical switches. However, such devices have typically demonstrated at frequencies below 18 GHz and require transitions to/from the RGW. The inventors have established an alternate design, which provides a reconfigurable power splitter and/or microwave switch, which is directly within the same metallic RGW waveguide technology. Such RGW power splitters and switches operating at higher frequencies, such as 26 GHz-40 GHz, for example.

Abstract: A single-layer substrate integrated directive broadside beam leaky-wave antenna is provided. Opposite ends of a leaky-wave structure are fed with anti-phase versions of a common signal, resulting in broadside frequencies being set apart from the open stopband. To achieve this, the common signal can be split into two equal length paths, one including a perfect electrical conductor (PEC) reflector and the other including a perfect magnetic conductor (PMC) reflector. Alternatively, the common signal can be split into two paths which differ in length by a half wavelength. A power splitter and feed horns can be used in the respective paths. The leaky-wave structure may have transverse slots which increase in width toward a midpoint of the structure. The antenna can be formed in a single planar portion of a lithographic structure, for example by patterning an upper conductive layer thereof.

Abstract: Microwave circulators are an essentially component in many microwave systems and whilst the waveguide technologies they are implemented in have evolved their design today still employs procedures that are typically approximate and have no regular approach, which in many instances is through dependence on empirical equations or considered a trade secret that gives an edge to commercial suppliers of microwave and RF circulators. The result is expensive isolators where high performance is required as they are merely selected out or require manual tuning. Further, for broadband systems, designer's resort to dividing into sub-bands deploying multiple narrower band circulators. Accordingly, the inventors present a design methodology based on an accurate closed form solution allowing the selection of suitable ferrite specifications for the required operating bandwidth as well as calculating the ferrite disc impedance allowing the necessary matching network to be designed and the circulator design completed.

Abstract: A compact high efficiency waveguide feed for reflector antennas includes a dielectric loaded aperture at its end for radiating energy to the reflector. The feed comprises a circular waveguide that carries the dominant TE11 mode, and terminates in a dielectric rod with an end cap. The exposed length of the dielectric rod between the end cap and the waveguide end constitutes a cylindrical aperture that radiates towards the reflector. The end cap and dielectric aperture dimensions are optimized for reflector high efficiency. Its small diameter provides an extremely compact feed, which reduces the sidelobes and operates well with both deep and shallow reflectors. As a result, high efficiency and low sidelobe performance can be obtained with symmetric centre fed reflectors.