Systems and methods for providing an antenna

An antenna assembly, comprising:

• an antenna reflector;
• a first circularly polarized antenna disposed on a first side of the antenna reflector and having a first circular polarization;
• a second circularly polarized antenna disposed on an opposite second side of the antenna reflector and having a second circular polarization opposite to the first circular polarization;
• and
• a circuit configured to perform the following operations when the antenna assembly is in use:
• receive, from the first circularly polarized antenna, a first signal comprising a desired signal emitted from a first signal source located at a first altitude higher than a second altitude of the antenna assembly and an interfering signal emitted from a second signal source located at a third altitude lower than the second altitude;
• receive the interfering signal from the second circularly polarized antenna;
• generate a second signal by shifting a phase of the interfering signal which was received at the second circularly polarized antenna by an amount to cause the second signal to be out-of-phase with the first signal;
• and
• provide an antenna pattern with a null at or below a horizon by destructively combining the second signal with the first signal.

An aerial vehicle, comprising:

• a fuselage;
• avionic electronics that are disposed in the fuselage and comprise an electronic circuit configured to receive and transmit signals using an antenna assembly, the antenna assembly comprising:
• an antenna reflector;
• a first circularly polarized antenna disposed on a first side of the antenna reflector and having a first circular polarization;
• a second circularly polarized antenna disposed on an opposite second side of the antenna reflector and having a second circular polarization opposite to the first circular polarization;
• and
• a circuit configured to perform the following operations when the antenna assembly is in use:
• receive, from the first circularly polarized antenna, a first signal comprising a desired signal emitted from a first signal source located at a first altitude higher than a second altitude of the antenna assembly and an interfering signal emitted from a second signal source located at a third altitude lower than the second altitude;
• receive the interfering signal from the second circularly polarized antenna;
• generate a second signal by shifting a phase of the interfering signal which was received at the second circularly polarized antenna by an amount to cause the second signal to be out-of-phase with the first signal;
• and
• provide an antenna pattern with a null at or below a horizon by destructively combining the second signal with the first signal.