CAJ | 학술논문

受卫星信道热噪声、多普勒、畸变影响,传统八进制相位键控(8PSK)接收机性能不佳,速率不高,较少应用于航天测控通信系统.针对这一问题,设计并实现了一种基于FPGA的航天测控系统宽带8PSK解调高速数传接收机,采用Gardner算法实现时钟恢复,利用基于最大似然估计的鉴相算法完成载波同步,并用分数间隔的并行恒模均衡算法提高接收性能.该技术已应用于某接收系统并实现了600 Mb/s 8PSK信号解调,误码率在1×10-3~1×10-8之间时,解调损失与理论值不超过2 d B.宽带8 P S K解调高速数传接收机可为我国二代中继系统提供支持.
수위성신도열조성、다보륵、기변영향,전통팔진제상위건공(8PSK)접수궤성능불가,속솔불고,교소응용우항천측공통신계통.침대저일문제,설계병실현료일충기우FPGA적항천측공계통관대8PSK해조고속수전접수궤,채용Gardner산법실현시종회복,이용기우최대사연고계적감상산법완성재파동보,병용분수간격적병행항모균형산법제고접수성능.해기술이응용우모접수계통병실현료600 Mb/s 8PSK신호해조,오마솔재1×10-3~1×10-8지간시,해조손실여이론치불초과2 d B.관대8 P S K해조고속수전접수궤가위아국이대중계계통제공지지.
@@@@Because of the thermal noise,large Doppler and intersymbol interference in a satellite communication link,high data rate receiver(HDR)with 8-Phase Shift Keying(8PSK)demodulation is used in tracking and data relay satellite system(TDRSS). A wideband 8PSK demodulation technology is proposed. The technology employs Gardner algorithm as timing synchronizer,Maximum Likelihood(ML)Decision-Directed(DD)method as phase detector and a fractionally spaced constant modulus algorithm(FS-CMA)equalization to improve demodulation performance.A receiver based on the technology is implemented by using field programmable gate array (FPGA) and a 600 Megabits per second(Mbps)8PSK signal has been tested. According to the theoretical approach,the demodulation loss difference between tested value and theoretical value is less than 2 dB when the Bit Error Rate (BER)ranges 1 × 10-3 to 1 × 10-8 . China′s new generation TDRSS can employ the receiver as its wideband 8PSK demodulator.