In this paper, we propose a Double-Space Time Transmit Diversity (D-STTD) communication system with Adaptive Modulation and Coding (AMC) scheme and analyze its performance using simulation experiments. The simulation ...In this paper, we propose a Double-Space Time Transmit Diversity (D-STTD) communication system with Adaptive Modulation and Coding (AMC) scheme and analyze its performance using simulation experiments. The simulation results show that the probability of selecting a high Modulation and Coding Scheme (MCS) level increased as the Signal to Noise Ratio (SNR) improved. Furthermore, the D-STTD communication system with AMC scheme provided a more uniform throughput distribution throughout the entire SNR range compared to its counterpart which did not apply AMC scheme. Also, the maximum throughput of the D-STTD communication system with AMC scheme was twice that of a conventional AMC communication system or a Space Time Transmit Diversity (STTD) communication system with AMC scheme.展开更多
In this paper, in order to increase system capacity and reduce the transmitting power of the user's equipment, we propose a efficient power estimation algorithm consisting of a modified open-loop power control (OL...In this paper, in order to increase system capacity and reduce the transmitting power of the user's equipment, we propose a efficient power estimation algorithm consisting of a modified open-loop power control (OLPC) and closed-loop power control (CLPC) for mobile satellite communications systems. The improved CLPC scheme, combining delay compensation algorithms and pilot diversity, is mainly applied to the ancillary ter-restrial component (ATC). ATC link in urban areas, because it is more suitable to the short round-trip delay (RTD). In the case of rural areas, where ATCs are not deployed or where a signal is not received from ATCs, transmit power monitoring equipment and OLPC schemes using efficient pilot diversity are combined and ap-plied to the link between the user's equipment and the satellite. Two modified power control schemes are ap-plied equally to the boundary areas where two kinds of signals are received in order to ensure coverage conti-nuity. Simulation results show that the improved power control scheme has good performance compared to conventional power control schemes in a geostationary earth orbit (GEO) satellite system utilizing ATCs.展开更多
文摘In this paper, we propose a Double-Space Time Transmit Diversity (D-STTD) communication system with Adaptive Modulation and Coding (AMC) scheme and analyze its performance using simulation experiments. The simulation results show that the probability of selecting a high Modulation and Coding Scheme (MCS) level increased as the Signal to Noise Ratio (SNR) improved. Furthermore, the D-STTD communication system with AMC scheme provided a more uniform throughput distribution throughout the entire SNR range compared to its counterpart which did not apply AMC scheme. Also, the maximum throughput of the D-STTD communication system with AMC scheme was twice that of a conventional AMC communication system or a Space Time Transmit Diversity (STTD) communication system with AMC scheme.
文摘In this paper, in order to increase system capacity and reduce the transmitting power of the user's equipment, we propose a efficient power estimation algorithm consisting of a modified open-loop power control (OLPC) and closed-loop power control (CLPC) for mobile satellite communications systems. The improved CLPC scheme, combining delay compensation algorithms and pilot diversity, is mainly applied to the ancillary ter-restrial component (ATC). ATC link in urban areas, because it is more suitable to the short round-trip delay (RTD). In the case of rural areas, where ATCs are not deployed or where a signal is not received from ATCs, transmit power monitoring equipment and OLPC schemes using efficient pilot diversity are combined and ap-plied to the link between the user's equipment and the satellite. Two modified power control schemes are ap-plied equally to the boundary areas where two kinds of signals are received in order to ensure coverage conti-nuity. Simulation results show that the improved power control scheme has good performance compared to conventional power control schemes in a geostationary earth orbit (GEO) satellite system utilizing ATCs.
