An outdoor unit, comprising: a band-pass filter device comprising a waveguide filter having a waveguide chamber, wherein the waveguide chamber comprises a high-pass portion, a connection portion, and a low-pass portion; a first circuit board section; a first antenna, disposed on the first circuit board section; a second circuit board section; and a second antenna, disposed on the second circuit board section; wherein the first antenna is configured to transmit a signal through the high-pass portion, the connection portion, and the low-pass portion of the waveguide filter, and the second antenna is configured to receive the signal; a frequency division element, coupled through an RF, Radio Frequency, printed circuit board to the band-pass filter device, wherein the frequency division element comprises: a first waveguide formed by a molded upper part and a molded lower part, wherein the first waveguide at least comprises a first descending portion gradually extended downwardly from a reference plane formed by a first line oriented in a longitudinal direction (x) of the frequency division element and a second line perpendicular to the first line and oriented in a direction (y) along a narrow side of the first descending portion, and a first terminal bending portion connected to an end of the first descending portion, wherein the first terminal bending portion has a first chamfer angle, and an edge of where the first chamfer angle bends is positioned in the reference plane, and the upper part of the first waveguide and the lower part of the first waveguide meet at the edge of where the first chamfer angle bends. a band-pass filter device comprising a waveguide filter having a waveguide chamber, wherein the waveguide chamber comprises a high-pass portion, a connection portion, and a low-pass portion; a first circuit board section; a first antenna, disposed on the first circuit board section; a second circuit board section; and a second antenna, disposed on the second circuit board section; wherein the first antenna is configured to transmit a signal through the high-pass portion, the connection portion, and the low-pass portion of the waveguide filter, and the second antenna is configured to receive the signal; a waveguide filter having a waveguide chamber, wherein the waveguide chamber comprises a high-pass portion, a connection portion, and a low-pass portion; a first circuit board section; a first antenna, disposed on the first circuit board section; a second circuit board section; and a second antenna, disposed on the second circuit board section; wherein the first antenna is configured to transmit a signal through the high-pass portion, the connection portion, and the low-pass portion of the waveguide filter, and the second antenna is configured to receive the signal; a frequency division element, coupled through an RF, Radio Frequency, printed circuit board to the band-pass filter device, wherein the frequency division element comprises: a first waveguide formed by a molded upper part and a molded lower part, wherein the first waveguide at least comprises a first descending portion gradually extended downwardly from a reference plane formed by a first line oriented in a longitudinal direction (x) of the frequency division element and a second line perpendicular to the first line and oriented in a direction (y) along a narrow side of the first descending portion, and a first terminal bending portion connected to an end of the first descending portion, wherein the first terminal bending portion has a first chamfer angle, and an edge of where the first chamfer angle bends is positioned in the reference plane, and the upper part of the first waveguide and the lower part of the first waveguide meet at the edge of where the first chamfer angle bends. a first waveguide formed by a molded upper part and a molded lower part, wherein the first waveguide at least comprises a first descending portion gradually extended downwardly from a reference plane formed by a first line oriented in a longitudinal direction (x) of the frequency division element and a second line perpendicular to the first line and oriented in a direction (y) along a narrow side of the first descending portion, and a first terminal bending portion connected to an end of the first descending portion, wherein the first terminal bending portion has a first chamfer angle, and an edge of where the first chamfer angle bends is positioned in the reference plane, and the upper part of the first waveguide and the lower part of the first waveguide meet at the edge of where the first chamfer angle bends.