Active antenna

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

Hybrid Electromagnetic and Non-Linear Modeling and Design of SIW Cavity-Backed Active Antennas

Abstract: ─ This paper presents the modeling and implementation of planar passive and active cavity-backed antennas in substrate integrated waveguide (SIW) technology. The cavity-backed topology helps suppressing the undesired surfacewave modes and may provide better phase noise performance in the antenna oscillator. The use of SIW technology allows for a compact and costeffective implementation of the structure. The design of the active antenna involves both electromagnetic full-wave modeling for the radiating structure and nonlinear analysis of the active circuitry through harmonic balance and transient simulations. Single substrate prototypes of both passive and active antennas operating in X band are presented and measured, showing good agreement with simulated results. Index Terms ─ Active antenna, cavity-backed antenna, harmonic-balance technique, substrate integrated waveguide (SIW).

5G Over-the-Air Conformance Testing

Abstract: Base station conformance testing Over-the-air has recently been adopted in 5G3GPP standardization. For an integrated Active antenna system, base band algorithms, radio and antenna parts are integrated into one enclosure, without access to physical antenna ports. Therefore the entire system needs to be tested Over-the-air. This approach comes with a set of challenges and changes in the requirements definitions compared to traditional conducted testing of a single transceiver branch. Relevant Over-the-air conformance parameters for Active antenna systems are discussed here as well as challenges, possibilities and agreed solutions of the corresponding measurements. Specifically, sparse sampling and near field measurements as well as Reverberation chambers are discussed. Moreover, the role of Measurement uncertainty in the standards is described.

Four Knife-Edge Diffraction With Antenna Gain Model for Generic Blockage Modelling

Abstract: With the recent adoption of millimeter-wave spectrum in cellular communications, deployment of active antenna arrays and use of beamforming become vital to compensate for the increased path loss. However, directional high-frequency signals may suffer heavy attenuations due to blockage effects. Therefore, blockage modelling that adequately incorporates the effects of beamforming becomes increasingly relevant. We propose a Four Knife-Edge Diffraction with antenna Gain (4KED-G) model, a deterministic approach to model blockage with broad applicability. The 4KED-G model advances upon the existing models in its inclusion of both angular antenna gains and the diffraction from all the four edges of a rectangular screen blocker, leading to a more general and flexible blockage modelling approach compared to existing widely accepted blockage models. We theoretically show that the proposed generalised model incorporates the strengths of these existing models, while overcoming their shortcomings in establishing applicability to wider range of blockage scenarios. We validate the generalised model against known knife-edge diffraction blockage models for specific scenarios.

Planar antenna for steering radiation beams

Abstract: The present invention relates to a planar radiation beam control antenna, and more specifically, to a planar radiation beam control antenna which actively adjusts a beam by constituting an array antenna system in a planar shape and using an electrical switching circuit. According to an embodiment of the present invention, the planar radiation beam control antenna comprises: a base substrate which has a plane in an X-axis direction and a Y-axis direction and a depth in a Z-axis direction; a signal supply via hole which is formed to penetrate the base substrate having the depth in the Z-axis direction; an active antenna which is disposed on the top surface of the base substrate and includes a horizontal dipole antenna including two unit antennas spaced apart from each other in the X-axis direction and a vertical dipole antenna including two unit antennas spaced apart from each other in the Y-axis direction, wherein the horizontal dipole antenna and the vertical dipole antenna are spaced apart from each other and intersect with each other at a right angle in a cross shape; a switching element which is disposed on the bottom surface of the base substrate and supplies a signal to either of the horizontal dipole antenna and the vertical dipole antenna; a signal supply line of the active antenna which electrically connects the active antennal and the switching element through the signal supply via hole; and a plurality of passive parasitic antennas which are spaced apart from the active antennal on the top surface of the base substrate and emit a coupling signal of the active antenna.

Active wideband antenna for underwater tomography (1 GHz)

Abstract: A new active antenna has been designed to measure electromagnetic fields in water. It combines a differential wideband amplifier and a dipole, the characteristics of which have been designed to provide a constant gain on the bandwidth of the antenna. The small size of the dipole reduces the mask effect. The designed antenna is a symmetrical reception antenna for the electromagnetic field measurement in water in the frequency range of 100 MHz to 1 GHz and it introduces few disturbances. A possible application will be the microwave imaging of immersed objects.