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Chaotic antenna array (CAA)s are phased antenna arrays in which individual elements are randomized in their array position, shape, and feed line length. These randomizations generate spatially dependent large scale phase errors (with respect to antenna elements of a uniform array) that enables distinct physical layer security solutions not available to other wireless systems. Herein, a preliminary study on one such novel method, developed to combat eavesdropping is presented. In the proposed method, the CAA equipped transmitter intentionally distorts its signals based on its own array factor (AF) which includes the phase errors. This distortion significantly hampers demodulation at an eavesdropper, while a legitimate receiver that is aware of the phase errors can compensate for the added distortion.
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L Band Phased Array Feed Noise Figure and Radiation Efficiency Measurement with the Antenna Y Factor Method
The noise performance of a high sensitivity, wide-field astronomical phased array feed receiver can be characterized by measurements using the antenna Y factor method. These measurements are used to determine figures of merit for an active array receiver. Antenna elements for the Advanced L Band Phased Array Camera for Astronomy (ALPACA) were measured using the antenna Y factor method to determine the active array and receiver noise figure, the antenna loss, receiver equivalent noise temperature, and radiation efficiency of the system over its 500[Formula: see text]MHz operating bandwidth. The completed ALPACA instrument will feature a fully cryogenic design with both the low-noise amplifiers and array elements cryogenically cooled. The uncooled performance measurements from the antenna Y factor method are used to extrapolate the elements cryogenic radiation efficiency and antenna loss showing that it is expected that the elements will contribute less than 1 K to the overall system noise temperature. These results validate the antenna Y factor method to measure key antenna parameters such as the antenna radiation efficiency and show that the instruments front-end array and electronics meets expected performance targets.
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- Award ID(s):
- 1636645
- PAR ID:
- 10416057
- Date Published:
- Journal Name:
- Journal of Astronomical Instrumentation
- ISSN:
- 2251-1717
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1142/S2251171723500022
