Active antenna

About: Active antenna is a research topic. Over the lifetime, 2246 publications have been published within this topic receiving 26493 citations.

Single feed antenna with radiation pattern diversity

Abstract: A vehicle diversity antenna system comprising a single-fed element together with a loaded parasitic element is described Different termination loads on the parasitic element give rise to variations in the radiation patterns that are comparable with a four-element diversity system There was good agreement between measured parameters and simulations

Architecture and interconnect technologies for a novel conformal active phased array radar module

Abstract: Highly integrated transmit/receive modules are key components for modern active phased array radar systems. This paper describes architecture and related interconnect technologies for a novel transmit/receive module with integrated radiating element and circulator for X-band applications. It allows the realization of future planar or conformal active antenna arrays with low installation depth as well as high maintainability performance.

Dual polarization spiral antenna

Abstract: An element antenna for use with a plurality of similar element antennas in an array. The element antenna receives and reradiates circular polarized electromagnetic energy such that the reradiated energy is of the same polarity as the received energy, independently of the geometric polarization element antenna. The element antenna includes a plurality of elongated, electrically conductive arms, each having an intermediate portion located in an annular active antenna region where circular polarized electromagnetic energy is received and reradiated. The arms of the element antenna are configured so that they define a geometric polarization element antenna of a given circular polarity so that currents induced in the respective intermediate arm portions from received energy, flow towards specific arm ends in dependence upon the polarity of the received energy. The currents are acted upon so that they re-enter the active region having their relative phases controlled in such a manner that the reradiated energy is of the same circular polarity as the received energy.

Parasitic elements diversity antenna

Abstract: The invention relates to an antenna diversity comprising a first and a second antenna element one of which is operated in an active mode whereas the other one of which is operated in a parasitic mode. It is the object of the present invention to further minimize the amount of mismatch by still being able to maximize a predetermined signal quality criterion for the electromagnetic signal on the active path between the active antenna and the transceiver. This object is solved by a switching unit 120 for either operating the first antenna element in the parasitic mode and simultaneously operating the second antenna element in the active mode or vice versa and by providing a pre-selection unit 130 as well as a selection unit 140 for selecting an optimal configuration for the antenna diversity ensuring that the amount of said mismatch is below a predetermined threshold value and that simultaneously a predetermined quality criterion for the transceived electromagnetic signal is fulfilled best. The antenna diversity further comprises a control unit 150 for adjusting said selected configuration. The invention further relates to a method for operating such an antenna diversity.

Full-dimensional MIMO for future cellular networks

Abstract: Full-dimensional multiple input multiple output (FD-MIMO) is a practical implementation of massive MIMO in cellular communication systems. FD-MIMO relies on an active two-dimensional antenna grid at the base stations and harvests the benefits of both azimuth and elevation beamforming. This paper briefly introduces the concept of FD-MIMO, and surveys the recent research results and applications of active antenna systems (AAS) technology. The key concepts discussed range from antenna patterns and channel modeling to vertical sectorization and heterogeneous networks deployment. The paper focuses on the benefits of FD-MIMO in an urban environment with high rises and three-dimensional user deployment. It demonstrates the importance of FD-MIMO in enhancing the performance of cellular networks.