Wide Angle Phase-Shifterless Beam Scanning in Unilaterally Coupled Active Antenna Arrays

Ragip ISPIR  Shigeji NOGI  Minoru SANAGI  

IEICE TRANSACTIONS on Electronics   Vol.E82-C    No.7    pp.1188-1194
Publication Date: 1999/07/25
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Issue on Microwave and Millimeter Wave Technology)
Category: Phased Arrays and Antennas
spatial power combining,  active antenna,  phased array,  beam scanning,  coupled oscillator,  unilateral coupling,  

Full Text: PDF>>
Buy this Article

In coupled oscillator arrays, it is possible to control the inter-element phase shift up to 180 by free-running frequency distribution based on injection-locking phenomenon. In this paper, a new technique to control the inter-element phase shift electronically up to the maximum extent of 360 is reported. Oscillators are unilaterally coupled to the preceding oscillator through one of the two paths, which differ from each other 180 in electrical length and each includes an amplifier. Turning on the desired amplifier one can control the phase shift either -180 to 0 or 0 to 180. The technique was applied in a three-element oscillator array each coupled to a patch antenna via a round aperture. The radiation beam of the array could be scanned 47 in total.