Active antenna

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

Controlling the gain of a remote active antenna

Abstract: A receiver includes a tuner and a circuit. The tuner receives an indication of a radio frequency signal from an antenna feedline in response to the radio frequency signal being provided to the antenna feedline by an amplifier. The circuit transmits a control signal to the antenna feedline to control a gain of the amplifier in response to a strength of the radio frequency signal.

Pattern-Reconfigurable Self-Oscillating Active Integrated Antenna With Frequency Agility

Abstract: A frequency-agile pattern-reconfigurable self-oscillating active integrated antenna (AIA) is investigated in this paper. With the aid of two PIN diodes and a varactor, the proposed active antenna shows pattern reconfigurability and frequency tunability at the same time. The antenna, composed of two monopoles and a semi-ring radiator, can be switched between four states, with two featuring omnidirectional patterns and the other two having end-fire radiation. The polarizations of the two omnidirectional states are spatially orthogonal to each other. By embedding a varactor diode, the voltage-controlled tuning range is from 4.27 to 4.94 GHz, while the effective isotropic radiated power (EIRP) varies from 5.4 to 9.3 dBm. The phase noise is better than ${-}102.7$ dBc/Hz at a 1-MHz offset from the carrier frequency.

A single-layer CPW-fed active patch antenna

Abstract: A single-layer CPW-fed active patch antenna oscillator at 2.76 GHz is presented. The patch antenna acts both as a resonator and a radiator. Electromagnetic coupling is utilized for providing the appropriate closed-loop positive feedback. The active antenna is built around a commercially available GaAs MMIC on a low-permittivity /spl epsiv//sub r/=2.33 Duroid 5870 substrate. The measured effective isotropic radiated power (EIRP) is 20 dBm, whereas the front-to-back ratio is about 12 dB with the cross-polarized fields better than -15 db. The measured phase noise is -87.5 dBc/Hz at a 100-kHz offset away from the carrier. The structure only requires a single substrate, is compatible with uniplanar technology, and results in a low-component count.