Multiband tunable dielectric resonator filters

We present here a new type of DR filters. The resonators have the shape of a truncated cone and their couplings are tuned by moving the resonators itself. Therefore, the layouts do not require the need of coupling screws and many of them do not even require the need of the irises. The unique shape makes the complete control of the strong couplings possible through the resonator movement. Using this technique we can build bandwidth tunable filters, i.e. different bandwidths in the same housing. Different measurements are presented with the same housing tuned from 1 MHz to 20 MHz. The technique also allows us to achieve up to 200 MHz bandwidth at 2 GHz, which is an order of magnitude greater than the present bandwidths that can commonly be achieved by standard DR filters. The new filters are simple in construction, with high Q and work particularly well at high dielectric constants. They can therefore be very small, compact and easily tunable. The unique layout intrinsically allows the implementation of the new cross-couplings. To our knowledge this is a breakthrough technology and all these are done for the first time.