Abstract: An embodiment of an antenna includes first and second transmission lines, first antenna elements, and second antenna elements. The first transmission line is configured to guide a first signal such that the first signal has a characteristic of a first value, and the second transmission line is configured to guide a second signal such that the second signal has the same characteristic but of a second value that is different than the first value. The first antenna elements are each disposed adjacent to the first transmission line and are each configured to radiate the first signal in response to a respective first control signal, and the second antenna elements are each disposed adjacent to the second transmission line and are each configured to radiate the second signal in response to a respective second control signal. Such an antenna can have better main-beam and side-lobe characteristics, and a better SIR, than prior antennas.

Abstract: An embodiment of a radar subsystem includes at least one antenna and a control circuit. The at least one antenna is configured to radiate at least one first transmit beam and to form at least one first receive beam. And the control circuit is configured to steer the at least one first transmit beam and the at least one first receive beam over a first field of regard during a first time period, and to steer the at least one first transmit beam and the at least one first receive beam over a second field of regard during a second time period.

Abstract: According to an embodiment, an antenna includes a conductive antenna element, a voltage-bias conductor, and a polarization-compensation conductor. The conductive antenna element is configured to radiate a first signal having a first polarization, and the voltage-bias conductor is coupled to a side of the antenna element and is configured to radiate a second signal having a second polarization that is different from the first polarization. And the polarization-compensating conductor is coupled to an opposite side of the antenna element and is configured to radiate third a signal having a third polarization that is approximately the same as the second polarization and that destructively interferes with the second signal. Such an antenna can be configured to reduce cross-polarization of the signals that its antenna elements radiate.

Abstract: In an embodiment, an antenna includes a one-dimensional array of antenna cells, a signal feed, and signal couplers. The antenna cells are each spaced from an adjacent antenna cell by less than one half a wavelength at which the antenna cells are configured to transmit and to receive, are configured to generate an array beam that is narrower in a dimension than in an orthogonal dimension, and are configured to steer the array beam in the dimension. And the signal couplers are each configured to couple a respective one of the antenna cells to the signal feed in response a respective control signal having an active level. For example, the antenna cells can be arranged such that a straight line intersects their geometric centers.

Abstract: An embodiment of an antenna array includes a transmit antenna and a receive antenna. The transmit antenna has, in one dimension, a first size, and has, in another dimension that is approximately orthogonal to the one dimension, a second size that is greater than the first size. And the receive antenna has, in approximately the one dimension, a third size that is greater than the first size, and has, in approximately the other dimension, a fourth size that is less than the second size. For example, such an antenna array, and a radar system that incorporates the antenna array, can provide a high Rayleigh resolution (i.e., a narrow Half Power Beam Width (HPBW)) with significantly reduced aliasing as compared to prior antenna arrays and radar systems for a given number of antenna-array channels.