Abstract: In imaging radar, examples are directed to uses of multiple sets of transmit antenna included with transceiver circuitry, for transmitting in a plurality of modes. Transmissions may involve having at least one transmit antenna, from each of at least two of the multiple sets, to transmit continuous-wave energy concurrently (simultaneously) in one or more of the plurality of different modes. Transceiver circuitry may include multiple receive antennas which may be receiving reflections of the continuous-wave energy from various targets. Signals from the multiple receive antennas may route to signal processing circuitry. The signal processing circuitry may respond to the received reflections of the continuous-wave energy by assessing differences in antenna gain and/or phase due to transmit antenna position associated with the received reflections.

Abstract: A dual polarized antenna is described with a dual feed that is suitable for cross polarization isolation. In an example, an antenna has a waveguide having a first rectangular face at an end, a second rectangular face at a second opposite end, and a radiating face between the first rectangular face and the second rectangular face. A first feed is configured to feed a first radio signal having a first polarization into the waveguide. A second feed is configured to feed a second radio signal having a second polarization orthogonal to the first polarization into the waveguide. A first plurality of polarized emitters on the radiating face are arranged in a first line along the radiating face to emit the first radio signal, and a second plurality of polarized emitters on the radiating face are arranged in a second line along the radiating face to emit the second radio signal.

Abstract: An apparatus comprising a processor configured to: receive an input dataset indicative of radar signals received at a plurality of antenna elements from a plurality of targets; define a matrix, Ã, of direction-of-arrival-angle vectors representing an expected response of the radar signals from the target and comprising a function of a direction of arrival angle relative to the antenna elements and including antenna-imperfection-factors that represent the angle dependent effect of antenna imperfections; define an objective function based on the input dataset and the matrix; search for a set of the direction of arrival angles for each of the plurality of targets by the repeated evaluation of the objective function for a plurality of candidate matrices based on matrix A, wherein said set is derived from one of the candidate matrices of the plurality of candidate matrices that provides a maximum or minimum evaluation of the objective function.

Abstract: In imaging radar, examples are directed to uses of multiple sets of transmit antenna included with transceiver circuitry, for transmitting in a plurality of modes. Transmissions may involve having at least one transmit antenna, from each of at least two of the multiple sets, to transmit continuous-wave energy concurrently (simultaneously) in one or more of the plurality of different modes. Transceiver circuitry may include multiple receive antennas which may be receiving reflections of the continuous-wave energy from various targets. Signals from the multiple receive antennas may route to signal processing circuitry. The signal processing circuitry may respond to the received reflections of the continuous-wave energy by assessing differences in antenna gain and/or phase due to transmit antenna position associated with the received reflections.

Abstract: The disclosure relates to a doppler division multiplexing MIMO radar system. Example embodiments include a doppler division multiplexing, DDM, multiple input multiple output, MIMO, radar system (400) comprising: a transmitter (401) connected to a plurality of transmitter antennas (4021?N) via a corresponding plurality of signal paths (4031?N) of different electrical lengths (L1?N) such that a phase of a signal transmitted by the transmitter (401) is different at each of the plurality of transmitter antennas (4021?N).