2003 Fiscal Year Final Research Report Summary
Beamforming of active antenna array with self-oscillating harmonic mixers
Project/Area Number |
14550324
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
電子デバイス・機器工学
|
Research Institution | OKAYAMA UNIVERSITY |
Principal Investigator |
SANAGI Minoru Okayama University, Graduate School of Natural Science Technology, Lecturer, 大学院・自然科学研究科, 講師 (80226026)
|
Co-Investigator(Kenkyū-buntansha) |
NOGI Shigeji Okayama University, Graduate School of Natural Science Technology, Professor, 大学院・自然科学研究科, 教授 (10033250)
|
Project Period (FY) |
2002 – 2003
|
Keywords | microwave / active antenna / self-oscillating mixer / injection locking / phased array / beamforming |
Research Abstract |
Beam control using active antenna arrays with self-oscillating harmonic mixers has been investigated. The active antenna is composed of a patch antenna receiving RF signal and a parallel feedback type oscillator which operates as the self-oscillating harmonic mixer, and down-converts the received RF into IF signal. The mixer has two ports for local oscillating (LO) signal. One is an output port extracting the LO signal. The other is an input port for an injection signal to synchronize the local oscillation. The mixers can be coupled unilatarally without other nonreciprocal components by connecting the output port to the input port in the next mixer. In the unilaterally coupled array, the phase differents of the LO signals between the adjacent mixers can be varied without phase shifters in injection locking state by changing the local free-running frequencies of the self-oscillating mixers. The receiving pattern can be controlled by combining the IF signals from the individual active antennas, which have phases associated with the LO signals. The IF is different between the RF and double of the LO frequency so that arbitrary phase differences from 0 to 2π radian can be providedto the output IF signals. The experiments using the two- and three-element arrays demonstrated beam control capability. In addition, conversion efficiency from RF to IF was increased by optimizing coupling strength of a directional coupler on a feedback loop in the self-oscillating mixer.
|
Research Products
(4 results)