Abstract: An antenna array feed network includes two or more antenna elements, a 180° hybrid coupler, one or more combiners, two or more transceiver systems including a secondary transceiver system with a transceiver, a diplexer, and amplifier with each remaining transceiver system including a transceiver, a diplexer, a directional coupler, a RF switch, a preamplifier, a network circulator, a programmable attenuator, and an amplifier. The two or more antenna elements form an antenna array. The 180° hybrid coupler provides amplitude controlled null steering and two separate RF signals for an individual port of the antenna array. The programmable attenuator provides automated null steering algorithms for the antenna array feed network. The analog phase shifter equalizes magnitudes of a phase of the two more antenna elements. The one or more combiners feed two or more transceiver systems into the 180° hybrid coupler or the antenna elements into the 180° hybrid coupler.

Abstract: Antenna Array for passively modulating radio frequency signals. Specifically, an antenna array or system comprising a plurality of retroreflective antennas configured to passively receive a radiofrequency (RF) signal from a source, and configured to reflect the RF signal; and a passive modulation circuit, electrically connected to the plurality of retroreflective antennas, configured to modulate the RF signal to represent a code, wherein the code comprises information, and further comprising: a plurality of RF switches.

Abstract: Antenna Array for passively modulating radio frequency signals. Specifically, an antenna array or system comprising a plurality of retroreflective antennas configured to passively receive a radiofrequency (RF) signal from a source, and configured to reflect the RF signal; and a passive modulation circuit, electrically connected to the plurality of retroreflective antennas, configured to modulate the RF signal to represent a code, wherein the code comprises information, and further comprising: a plurality of RF switches.

Abstract: Methods for establishing metamaterial transmission line (MTM TL's) for a phased array antenna can include the initial step of defining a defining a Composite Right/Left Hand (CRLH) CRLH unit cell architecture. A family of unit cells using CRLH TL microstrip architecture can be constructed so that each of the CRLH unit cells have the same physical length, but different cell phases and cell phase slopes. To do this, the stub length of each CRLH unit cell can be varied. Once the family of CRLH unit cells is constructed, different numbers of different CRLH unit cells from the family can be combined with different numbers of conventional right hand TL's, which results in TL's for a phased array antenna that each have the same overall phase and overall phase slope not only at the design frequency f0, but over the entire design frequency band for the antenna.