Banca de DEFESA: JOEL EUGÊNIO CORDEIRO JUNIOR

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOEL EUGÊNIO CORDEIRO JUNIOR
DATE: 01/12/2023
TIME: 14:00
LOCAL: https://us02web.zoom.us/j/87392883963?pwd=Q1UzVFJGWFNnaloxVkF0M2VoZGIzZz09
TITLE:

Analysis of the Effect of Epidemic Interference on Digital Communications Systems

KEY WORDS:

Epidemic Interference Model; Digital Communications Systems; Gauss-Hermite quadrature

PAGES: 123
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUBÁREA: Telecomunicações
SPECIALTY: Sistemas deTelecomunicações
SUMMARY:

One of the main problems of cellular mobile communication systems is the interference. The growing demand for connectivity can make this problem even more challenging, creating scenarios with high device density and massive connections. Thus, it is important to investigate and understand different interference models in wireless communication channels. The Epidemic Interference (EI) model was recently proposed to represent the situation in which many devices begin transmitting simultaneously, causing a rapid increase in interference levels on a shared channel. Based on this interference model, this thesis presents a study of the effect of EI on digital communication systems in terms of signal synchronization for coherent demodulation, outage probability, symbol error rate, and the theoretical capacity of the channel affected by EI. In order to evaluate the effect of EI on the received signal synchronization, the expressions for the theoretical limit of the variance of the carrier phase estimation error are derived. These expressions are evaluated by numerical methods for cases in which
the received signal is an unmodulated carrier and a digital phase modulated signal. The impact of EI is also analyzed by the outage probability and symbol (and bit) error probability expressions, which are derived for amplitude, phase and quadrature digital modulation schemes. Finally, the ergodic capacity of the channel in the presence of EI is evaluated. In addition to the numerical expression, approximate analytical expressions for the capacity are proposed. Due to the lognormal distribution of the interference power, the expressions presented in this thesis are assessed by the Gauss-Hermite quadrature. Computer simulations were performed to validate these expressions. For the analyzed cases, it is observed that the presence of EI increases the phase estimation error, the outage probability, and the symbol (and bit) error rates. Also, EI decreases the channel capacity. The partial results also show that the performance of the studied systems depends both on the mean power of EI and on the spread of the interfering power distribution.

COMMITTEE MEMBERS:
Externo à Instituição - FABRICIO BRAGA SOARES DE CARVALHO
Interno - 1546333 - KARCIUS DAY ROSARIO ASSIS
Presidente - ***.487.304-** - MARCELO SAMPAIO DE ALENCAR - UFPB
Externo à Instituição - RAÍSSA BEZERRA ROCHA - UFS
Externo à Instituição - WASLON TERLLIZZIE ARAÚJO LOPES