Text Transmission Using Multicarrier OFDM Based on Software-Defined Radio Technology in Indoor Channel with Multipath Fading

Multipath fading can cause the transmitted data to be damaged or interfere with, resulting in an inability to receive it without error by the receiver. This research examines the utilization of Multicarrier Orthogonal Frequency Division Multiplexing (OFDM) technology for data transmission. We employed Software Defined Radio (SDR) to analyze communication systems in both interior and outdoor environments to transmit text as a data through the use of USRP and SDR RTL as transmitter and receiver. The performance of text-based data transmission under multipath fading conditions is analyzed in this study by generating the parameter of Signal to Noise Ratio (SNR), Bit Error Rate (BER), and Complementary Cumulative Distribution Function (CCDF) curves. This study demonstrates that OFDM technology can enhance the quality of data transmission in multipath fading conditions. The highest SNR value achieved in this study was 16.3975 dB, with the lowest BER of $10^{\wedge}(-0.352543)$. This resulted in a total of 89.03% of data being received in the outdoor test environment. In the meantime, the lowest SNR value in this study is 7.18475 dB, and the lowest BER value is $10^{\wedge}(-0.359288)$. This results in a 75.74% percentage of data received in interior conditions. The BER value decreased as a result of the increase in SNR value, suggesting that the transmission quality improved under more minimal multipath fading conditions. Higher SNR values indicate reduced interference, which leads to a higher percentage of receive data and lower bit error rates.