Frequency Tunable Filter And Associated Apparatus

[0018] Certain terms are used in the description and claims to refer to particular elements. Those skilled in the art should understand that a manufacturer may use different terms to refer to the same component. The specification and claims do not use the difference in name as a way to distinguish components, but use the difference in function of components as a criterion for distinguishing. "Includes" and "comprising" mentioned throughout the description and claims are open-ended terms, so they should be interpreted as "including but not limited to...". Otherwise, the term "coupled" includes any direct and indirect means of electrical connection. Therefore, if it is described herein that a first device is coupled to a second device, it means that the first device may be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means.

[0019] Please refer to figure 1 , which shows a sche