Active antenna

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

A sequential power amplifier at 3.5 GHz for 5G applications

Abstract: In this paper, a broadband Sequential Power Amplifier (SPA) is designed and realized for the use in an active MIMO antenna around 3.5 GHz. For that purpose, specifications for the individual components are derived to yield optimum performance of the complete SPA when amplifying a mobile communication signal. In order to meet the size requirements of an active antenna, amplifier modules that include all necessary transformation and stabilization networks inside the package are developed. The SPA achieves a bandwidth of more than 1 GHz (RBW of 28%) and shows a peak drain efficiency of 47% in 8 dB backoff at 3.5 GHz. To transmit a complex signal such as QAM using the SPA, its two inputs have to be driven according to the system's characteristic curve. For the first time, modified constellation diagrams for each input have been derived to transmit a 16-QAM-modulated test signal with 10 MBaud at 3.2 GHz. For the amplification of this signal, the system shows an increase in drain efficiency of 10 %-points compared to a conventional class-B PA.

Active antenna array and method for relaying first and second protocol radio signals in a mobile communications network

Abstract: The present disclosure teaches an active antenna array for a mobile communications network. The active antenna array comprises a plurality of antenna elements, at least one first splitter, at least one amplifier and at least one first coupler. The first splitter forwards at least one of at least one individual first protocol receive signal and at least one individual second protocol receive signal in a receive direction from an individual one of the plurality of antenna elements. The at least one amplifier amplifies at least one of the individual first protocol receive signal and the individual second protocol receive signal. The at least one first coupler is located in the receive direction downstream of the at least one amplifier and is adapted to forward the at least one individual second protocol receive signal to a second protocol receiver.

Integrated MM-Wave MIMO Antenna with Directional Diversity using MEMS Technology

Abstract: This paper presents the design of a fully integrated antenna with directional diversity in the 60 GHz band using MEMS process on high resistivity silicon wafer. This active antenna designed for MIMO systems integrates switches and phase shifters.

Tunable Stacked Circular Patch Microstrip Antenna

Abstract: A Gunn diode loaded stacked circular patch antenna is proposed and analyzed It is found and threshold voltage of Gunn diode controls the performance of the antenna Various tunable frequency bands are obtained by selecting suitable bias voltage while antenna topology remains unchanged Antenna properties like return loss, in impedance, voltage standing-wave ratio (VSWR), bandwidth, etc, are calculated with the proposed model

A Microstrip Based Active Antenna Doppler Transceiver Module

Abstract: We present the design and test of a microstrip active transceiver element suitable for use as a CW Doppler module. The circuit consists of a microstrip annulus from which a small section has been removed, resulting in a two-port antenna. This antenna is then coupled to the drains of two FETs through a short section of microstrip line. By adjusting the length of this section of line, the oscillation condition is satisfied, the two FETs oscillate in the odd mode, and a microwave signal is radiated from the circuit. The Doppler-shifted return signal which is picked up by the antenna is applied back to the drain ports of the FETs, which also function as self-oscillating mixers. The IF signal is coupled out using audio transformers. By measuring the in-phase and out-of-phase IF signals, we can determine the co-polarized and cross-polarized components of the reflected signal.