1-2hit |
Sungho JEON Junghyun KIM Jaekwon LEE Young-Woo SUH Jong-Soo SEO
In this paper, we propose a power amplifier linearization technique combined with iterative noise cancelation. This method alleviates the effect of added noises which prevents the predistorter (PD) from estimating the exact characteristics of the power amplifier (PA). To iteratively cancel the noise added in the feedback signal, the output signal of the power amplifier without noise is reconstructed by applying the inverse characteristics of the PD to the predistorted signals. The noise can be revealed by subtracting the reconstructed signals from the feedback signals. Simulation results based on the mean-square error (MSE) and power spectral density (PSD) criteria are presented to evaluate PD performance. The results show that the iterative noise cancelation significantly enhances the MSE performance, which leads to an improvement of the out-of-band power suppression. The performance of the proposed technique is verified by computer simulation and hardware test results.
Jaekwon LEE Sanghwa LEE Dong Ku KIM
For Advanced Television Systems Committee (ATSC) digital terrestrial broadcasting systems, a transmitter identification (TxID) technique is introduced to analyze interference among broadcasting transmitters in single frequency networks (SFN). Based on the TxID analysis results, the transmit power and emission time delay of each broadcasting transmitter can be adjusted to minimize the effects of co- and adjacent- channel interference. For this reason, TxID has been recognized as an important feature in SFN configurations for ATSC 1.0 and 3.0 standards. Recently, there has been increasing interest in employing TxID for data transmission. This paper proposes a TxID based data transmission method for use with ATSC 1.0 and 3.0 standards. The major advantage of this data transmission method is its robustness while maintaining TxID properties. Simulations and laboratory tests demonstrate that the proposed technique can achieve a robust data transmission with backward compatibility to legacy ATSC 1.0 and 3.0 receivers.