학술논문

Performance Improvement of True Time Delay Based Centralized Beamforming Control With the Modulation Instability Phenomenon for Wireless Array Antennas
Document Type
Periodical
Source
Journal of Lightwave Technology J. Lightwave Technol. Lightwave Technology, Journal of. 42(6):1829-1835 Mar, 2024
Subject
Communication, Networking and Broadcast Technologies
Photonics and Electrooptics
Modulation
Optical fiber dispersion
Optical fibers
Frequency modulation
Optical fiber amplifiers
Amplitude modulation
Optical fiber networks
Array antennas
fifth-generation (5G)
Mach-Zehnder
modulation instability (MI)
true-time-delay (TTD)
Language
ISSN
0733-8724
1558-2213
Abstract
This paper proposes a novel method to enhance the performance of the modulator for fifth-generation wireless communication (5G) by exploiting modulation instability (MI). We show that MI can reduce the modulator's bias voltage ($V_\pi$) by generating carrier side-band gain, and increase the modulation BandWidth (BW), resulting in higher channel capacity, without changing the modulator structure. In receive mode of the array antenna, where the signal is very weak, high-frequency amplification is a high demanding solution to mitigate coverage issue. We also present a developed microwave-photonic beamforming bit-controller system for receiver-transmitter phased array antennas (PAAs), which are essential for high-capacity wireless communications like 5G. We employ a modulated frequency comb, exploiting MI fiber to achieve an amplified true-time delay (TTD) system for wide-coverage PAA beamforming and show that it can steer wideband high-frequency signals to a specific direction angle, avoiding beam-squint.