Subjects: Geosciences >> Space Physics submitted time 2016-04-22
Abstract：针对数传、测距一体化的调制方式高斯最小频移键控复合伪码测距(Gaussian minimum shift keying+pseudo-noise,GMSK+PN)信号的信噪比估计,提出了一种精度较高、复杂度较低的快速算法。该算法采用层状结构分解的方式,将信号分解为若干信号单元,对每一个分解的信号单元进行功率分配计算或信噪比估计,最后快速准确地计算出整个信号的信噪比。信噪比在1~13dB之间时,估计误差小于0.5dB。利用Simulink仿真工具,验证了该算法的有效性。
Peer Review Status:
Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2016-04-22
Abstract： For the small satellites formation flying， the distance between satellites must be determined and an adequate inter-satellites communication medium must be used to transmit the science data. In order to minimize device complexity， this paper studied a system capable of simultaneously transmitting high rate telecommunication and ranging. through simulations by Simulink in different ranging modulation index， obtained the bit error rate of telecommunication data. By analyzing the characteristics of GMSK+PN signal， an effective demodulation scheme for GMSK+PN is developed by this paper.
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2016-04-22
Abstract： In order to save channel resources， asynchronous digital multiplexer， which can multiplex different rate， different burst time slot digital source， has been widely applied. Aims to reduce the maximum extent possible source packet data transmission delay， improve channel utilization， design scheme of a greedy asynchronous dynamic digital multiplexer is proposed. The priority scheduling strategy of sources is given too. Two kinds of multiplex model are described by hardware description language. Simulations for greedy dynamic multiplexer and virtual channel multiplexer， under the condition of different physical frame length and two source model， have been carried out by Modelsim. The simulation results show that， for the average transmission delay and delay jitter， the greedy dynamic multiplexing is superior to the virtual channel multiplexing， and is more effective in saving resource of source cache.
Peer Review Status:Awaiting Review
Hits
Hits
Downloads
Comment