Millimeter wave band array antenna

1. A millimeter wave array antenna comprising:

a first dipole array antenna unit comprising a plurality of first +dipole members and a plurality of first −dipole members, the plurality of first +dipole members formed on an upper portion of a first substrate and configured to be provided with feed signals through a first feed line, the plurality of first −dipole members formed on a lower portion of the first substrate and joined with a ground plane formed on a lower portion of the first substrate; and

a slot antenna unit comprising a plurality of slot radiators, a third feed line, and a fourth feed line, the plurality of slot radiators formed on an upper portion of the first substrate, the third feed line formed on a lower portion of the first substrate and configured to provide feed signals to the plurality of slot radiators, the fourth feed line formed on an upper portion of a second substrate stacked onto an upper portion of the first substrate, the fourth feed line configured to provide feed signals to the plurality of slot radiators,

wherein the ground plane has a first sloped structure and a second sloped structure formed therein, the first sloped structure having an upward slope of a first angle toward a rightward direction from a point of junction with a first −dipole member, the second sloped structure having an upward slope of the first angle toward a leftward direction from the point of junction.

2. The millimeter wave array antenna of claim 1 , wherein the first sloped structure and the second sloped structure are formed for every point of junction between the plurality of first −dipole members and the ground plane.

3. The millimeter wave array antenna of claim 1 , further comprising:

a second dipole array antenna unit comprising a plurality of second +dipole members and a plurality of second −dipole members, the plurality of second +dipole members formed on an upper portion of the first substrate and configured to be provided with feed signals through a second feed line, the plurality of second −dipole members formed on a lower portion of the first substrate and joined with the ground plane formed on a lower portion of the first substrate.

4. The millimeter wave array antenna of claim 3 , wherein an array direction of the first dipole array antenna unit and an array direction of the second dipole array antenna unit are orthogonal to each other.

5. The millimeter wave array antenna of claim 4 , wherein the first +dipole members, the first −dipole members, the second +dipole members, and the second −dipole members are bent to an angle of 90 degrees or smaller.

6. The millimeter wave array antenna of claim 3 , wherein any one of the first dipole array antenna unit, the second dipole array antenna unit, and the slot antenna unit is selected for receiving feed signals.

7. The millimeter wave array antenna of claim 1 , wherein the third feed line and the fourth feed line provide feed signals having a phase difference of 90 degrees such that the slot radiators emit circularly polarized signals.

8. A millimeter wave array antenna comprising:

a first dipole array antenna unit comprising a plurality of first +dipole members and a plurality of first −dipole members, the plurality of first +dipole members formed on an upper portion of a first substrate and configured to be provided with feed signals through a first feed line, the plurality of first −dipole members formed on a lower portion of the first substrate and joined with a ground plane formed on a lower portion of the first substrate;

a second dipole array antenna unit comprising a plurality of second +dipole members and a plurality of second −dipole members, the plurality of second +dipole members formed on an upper portion of the first substrate and configured to be provided with feed signals through a second feed line, the plurality of second −dipole members formed on a lower portion of the first substrate and joined with the ground plane formed on a lower portion of the first substrate; and

a slot antenna unit comprising a plurality of slot radiators, a third feed line, and a fourth feed line, the plurality of slot radiators formed on an upper portion of the first substrate, the third feed line formed on a lower portion of the first substrate and configured to provide feed signals to the plurality of slot radiators, the fourth feed line formed on an upper portion of a second substrate stacked onto an upper portion of the first substrate, the fourth feed line configured to provide feed signals to the plurality of slot radiators,

wherein an array direction of the first dipole array antenna unit and an array direction of the second dipole array antenna unit are different.

9. The millimeter wave array antenna of claim 8 , wherein the array direction of the first dipole array antenna unit and the array direction of the second dipole array antenna unit are orthogonal to each other.

10. The millimeter wave array antenna of claim 9 , wherein the ground plane has a first sloped structure and a second sloped structure formed therein, the first sloped structure having an upward slope of a first angle toward a rightward direction from a point of junction with a first −dipole member, the second sloped structure having an upward slope of the first angle toward a leftward direction from the point of junction.

11. The millimeter wave array antenna of claim 10 , wherein the first sloped structure and the second sloped structure are formed for every point of junction between the plurality of first −dipole members and the ground plane.

12. The millimeter wave array antenna of claim 8 , wherein the first +dipole members, the first −dipole members, the second +dipole members, and the second −dipole members are bent to an angle of 90 degrees or smaller.

13. The millimeter wave array antenna of claim 8 , wherein the third feed line and the fourth feed line provide feed signals having a phase difference of 90 degrees such that the slot radiators emit circularly polarized signals.