Filters including detuned box section resonator configurations and/or resonators having beveled top surfaces

A filter, comprising:

• a housing having an input port and an output port;
• and
• first through fourth resonators mounted within the housing to extend upwardly from a floor of the housing,
• a first transmission line branch that connects the first resonator to the second resonator and the second resonator to the fourth resonator;
• and
• a second transmission line branch that connects the first resonator to the third resonator and the third resonator to the fourth resonator,
• wherein the first and second transmission line branches form a closed structure when viewed from above, and
• wherein the first resonator, the second resonator and the fourth resonator are configured to resonate within a passband of the filter, while the third resonator is configured to resonate outside the passband of the filter.

A filter, comprising:

• a housing having a floor;
• a metal wall that is integral with the floor extending upwardly from the floor;
• first through fourth resonators mounted within the housing to extend upwardly from the floor of the housing, the first through fourth resonators surrounding the wall when viewed from above,
• wherein the first through fourth resonators are configured to generate a transmission zero, and
• wherein the first resonator, the second resonator and the fourth resonator are configured to resonate within a passband of the filter, while the third resonator is configured to resonate outside the passband of the filter.