为深入了解对称载波复用(Paired Carrier Multiple Access,PCMA)技术,为实际应用提供指导,对卫星通信PCMA应用开展研究.在介绍PCMA基本原理的基础上,对PCMA传输性能和抗截获性方面的优势进行分析.基于Ku波段转发器在北京地区的参数,计算在转发器下行功率受限和地球站上行功率受限情况下,不同口径天线地球站在不同调制方式和前向纠错(Forward Error Correction,FEC)编码方式下的信息速率和晴天链路余量.计算结果表明,当合作通信的2个地球站发射能力足够时,在晴天链路余量不小于3 dB的情况下,PCMA比单路单载波(Single Channel Per Carrier,SCPC)信息速率至少提升40%.当一个地球站发射能力不足时,建议降低另一个站的信息速率,保持2个载波重叠,增加第三方装置截获信号的难度.
Application Study of PCMA for Satellite Communication
The application of Paired Carrier Multiple Access(PCMA)in satellite communication is studied to have a comprehensive understanding of this technology and provide guidance for its practical use.Based on an introduction of the basic principles,the advantages of PCMA in transmission performance and anti-interception capability are analyzed.The information rate and clear sky link margin of earth stations with antennas of different apertures under different modulation and Forward Error Correction(FEC)coding schemes are calculated based on the Ku-band transponder parameters in Beijing area with limited transponder down link power and limited earth station uplink power.The link budget result shows that PCMA achieves an increase of at least 40%in information rate as compared with Single Channel Per Carrier(SCPC)when the clear sky link margin is not less than 3 dB and the uplink power of two cooperative earth stations are sufficient.When the uplink power of one earth station is insufficient,it is suggested to decrease the information rate of another station to maintain the overlapping of two carriers so as to increase the difficulty of signal interception by third party facilities.