Provided is a high-frequency circuit apparatus and a communication apparatus whose consumption current is small and the inserting loss is small. Subsequently, the uneven, non-uniform passivation layer is subjected to a planarization process such as chemical mechanical polishing, mechanical abrasion, or etching. A hitch adapter is affixed to the bottom portion to secure the carriage guide assembly to a vehicle hitch. A cutout portion and gusset are provided in the top strap to permit the corner adapter to engage the side wall.