arXiv subjects

Hassan Zakeri

Publications and source records attributed to Hassan Zakeri.

2 recordsLinked to original sources

arXiv2023

Performance Improvement of True Time Delay Based Centralized Beamforming Control with the Modulation Instability Phenomenon for Wireless-Array Antennas

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 bias voltage of the modulator ($V_π$) 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) technique for wide-coverage PAA beamforming and show that it can steer wideband high-frequency signal to a specific direction angle, avoiding beam-squint.

physics.optics↗

arXiv2023

An Accurate Model to Estimate 5G Propagation Path Loss for the Indoor Environment

This paper presents a new large-scale propagation path loss model to design a fifth-generation (5G) wireless communication system for indoor environments. Simulations for the indoor environment, for all polarization at non-line-of-sight (NLOS) and line-of-sight (LOS), which are performed per meter over a distance of 47 m between each of the separated transmitter antenna (TX) and the receiver antenna (RX) positions to compare better the proposed extensive flexible path loss model with previous models. All the simulations are conducted at the Abu-rayhan buildings at the Amirkabir University of Technology. The results demonstrated that the simple presented model with a single parameter denoted ZMS can predict the expansive path loss over distance more accurately. The values of the path loss exponent (PLE) for the LOS scenario are simulated and achieved at 3.63, 1.81, and 3.42 for the V-H, V-V, and V-Omni antenna polarizations, and for NLOS is 6.11, 4.21, and 5.23 at the 28 GHz frequency for all the polarization antenna type V-H, V-V, and V-Omni, appropriately.

cs.IT↗