It can be concluded from (2) that the location of the TZ is a function of L2, and L2 changes with the length of A2. Note that the capacitance of A2 is negligible. Thus, it has less impact on the TZ location. A2 has a contrary relevance with the location of the TZ. For instance, if the length of A2 becomes 6.6, 4, and 3 mm, the location of the TZ will become 1.32, 1.67, and 1.9 GHz, respectively. Besides, if a parameter can control the first TZ, it subsequently can control the roll-off rate and the cut-off frequency with different proportion.