The state-of-the-art of RF capacitive tunable components (Invited)

An overview is given for the current state-of-the-art of tunable RF elements. For this purpose, tunable RF elements such as thin-film Barium Strontium Titanate (BST) varactors, Micro Electro Mechanical Systems (MEMS) based capacitive switch banks and varactors, as well as semiconductor based capacitive switch banks and varactors are reviewed. Their benefits and shortcomings are discussed and compared for various applications.