Abstract: Embodiments relate to two-dimensional antenna arrays. In one embodiment, an antenna array includes single-ended fed patch antennas and differentially fed patches. Field polarization of the radiated and/or received EM waves is different by 90 degrees for each different antenna type. Thus, an aligned polarization pattern can be achieved using orthogonal feeding direction for single-ended and differential patches. Embodiments can be used in radar or virtually any other 2D array antenna system.

Abstract: Embodiments relate to two-dimensional antenna arrays. In one embodiment, an antenna array includes single-ended fed patch antennas and differentially fed patches. Field polarization of the radiated and/or received EM waves is different by 90 degrees for each different antenna type. Thus, an aligned polarization pattern can be achieved using orthogonal feeding direction for single-ended and differential patches. Embodiments can be used in radar or virtually any other 2D array antenna system.

Abstract: A plurality of exchangeable, different piezoelectric pressure sensors (4) comprise integrated SAW elements (60) as identification units whose identification data can be read by an interrogation unit (3) via a common connection cable (61). The analysis unit (2) for the measurement signals and the interrogation unit (3) for the identification data can be connected by a common coupling unit (5) to the connection cable (61). The coupling unit (5) has a coupling capacity (6) which connects with high frequency the interrogation unit (3) to the signal line of the connection cable (61), as well as a coupling inductance (7) which connects with low frequency the load amplifier (1) of the analysis unit (2) to the connection cable (61), thus neatly separating the useful signal from the identification signal and keeping a high-impedance measurement chain from the sensor (4) to the input of the load amplifier (1). An SFSCW radar can further be used to improve interrogation of the identification data.