Compact Waveguide Load Using Planar Step Absorber

The patent transitions from conventional one-dimensional tapered pyramid loads to a two-dimensional planar step configuration. The load consists of a planar absorbing surface that steps inward from the waveguide wall, creating a two-dimensional impedance transition rather than a one-dimensional gradual taper. This dimensional change enables achieving good impedance matching over a broader bandwidth with a much shorter load length, as the step configuration provides abrupt impedance transformation that is more effective than gradual tapering.

The patent changes the geometric parameters of the load configuration from conventional pyramid shapes to a planar step structure with specific dimensions. The step height, step width, and length of the absorbing material are optimized parameters that can be adjusted to achieve impedance matching. By changing these geometric parameters, the load achieves effective energy absorption in a compact form factor, resolving the contradiction between absorption effectiveness and load size.

The patent introduces a thermal management intermediary system consisting of a cooling plate or heat sink in thermal contact with the absorbing material. This intermediary component facilitates heat transfer from the poor heat-conducting lossy material to an efficient heat dissipation path. The cooling plate acts as a thermal bridge, allowing the absorbing material to dissipate high power while the intermediary handles the heat management function, resolving the contradiction between power absorption and heat management.

The patent employs a composite structure combining the electromagnetic lossy material with a thermally conductive substrate or cooling plate. The composite construction allows the lossy material to perform its electromagnetic absorption function while the thermally conductive component provides efficient heat pathways. This composite approach enables the system to handle high power dissipation without excessive temperature rise, as the two materials complement each other's functional deficiencies.

The patent extracts the water cooling system from the load structure, eliminating the need for integrated cooling channels, pumps, and fluid management systems. Instead, the load uses a passive thermal management approach with direct thermal contact to a heat sink or cooling plate. This extraction of the active cooling system reduces device complexity while maintaining power handling capability through simplified thermal conduction paths.

The patent implements a self-cooling mechanism where the load structure itself provides thermal management through its geometric design and material selection. The planar step configuration and thermal contact with the waveguide walls or mounted heat sink enable passive heat dissipation without requiring external cooling systems. The load serves its own thermal management needs through conductive heat transfer, eliminating the need for complex active cooling infrastructure.