This paper presents a highly innovative approach of amplitude steering without the use of variable gain amplifiers (VGA). This approach involves the use of a Reconfigurable Ratio Power Divider (RRPD), and does not suffer from the instability, poor efficiency, and worsened SNR associated with the use of VGAs. The RRPD, which is reconfigured manually by means of a potentiometer, is used to feed a 2 x 1 antenna array. By varying the power dividing ratio of the RRPD, continuous beam steering is achieved through passive amplitude control. The antenna was designed to operate at 2.4 GHz and had a continuous steering range from 0° to 21° while maintaining a stable return loss around the centre frequency. An expression that relates the reconfigurable ratio to the variable resistance was derived empirically. The prototype amplitude steerable antenna was fabricated and measured to validate the analyses.
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