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Delay-multiply acquisition method is a well known acquisition method but is seldom used in ground GNSS receivers for the sensitivity loss introduced by the multiplication step. As to space-borne GNSS receivers, doppler offset may extend to tens of kHz due to rapid movement of space vehicles at a speed near the first cosmic velocity, which makes delay- multiply acquisition method a prior candidate...
We use a diluted refractory metal as a selective emitter/absorber to enhance the efficiencies of thermal-light and light-thermal conversions. The absorptivity (emissivity) was measured at high temperatures up to 750°C.
We present a direct sampling full-band capture receiver for cable and digital TV applications. It consists of a 28nm CMOS ADC-based direct sampling receiver and a 0.18um BiCMOS LNA. It is capable of receiving 158 channels from 48MHz to 1000MHz simultaneously, achieving up to 10Gb/s data throughput, while exceeding DOCSIS requirements. The CMOS receiver occupies 1mm2 area while consuming 300mW. The...
Spectrum prediction estimates channel future status from history statistics, which greatly improved the efficiency of spectrum sensing in cognitive radio networks. Current researches mainly focus on improving speed and accuracy of prediction. Few researches discuss the energy-efficient design of spectrum prediction. Since energy-efficient affect working hours and transmission efficiency, that is an...
The trajectory optimization problems of maximum impact angle about gun-launched missile which beam-riding guidance and homing guidance composite guidance program was used were studied in this paper. The flight trajectory of the missile was divided into four main phases: the climb phase, the turning phase, the search phase, the terminal guidance phase. Maximum impact angle was set as the optimization...
The role of priori knowledge in quantum information processing is explored by investigating probabilistic remote state preparation in this paper. For a case study, a comparison has been made among three efficient schemes, which are used to perform the remote preparation of an arbitrary quantum state. The comparison results indicate that one can take advantage of priori knowledge to add the total successful...
We propose a novel and robust method for laser phase noise compensation with low computational complexity. Experimental results show laser linewidth up to 1MHz can be successfully compensated for 114.8-Gb/s 16-QAM OFDM signals.
We propose a single-carrier direct detection optical communication system using the signal-carrier interleaved scheme. Simulation with total data rate of 66.7Gbps and transmission distance of 100km fiber is demonstrated to evaluate its performance.
We employ coherent detection and digital signal processing to characterize dynamic evolution of channel matrix in two-mode fibers. Experimental results reveal that the evolution frequency of channel matrix can reach as fast as 4 kHz.
By exchanging soft information between the detector and the channel decoder, an iterative receiver can significantly improve the performance compared to the non-iterative receiver. In this paper, a low complexity soft-input soft-output (SISO) fixed-complexity sphere decoding (FSD) algorithm is proposed for iterative MIMO receiver. The algorithm introduces a simplified parallel candidate adding (SPCA)...
Limitation of digital back propagation under the influence of polarization mode dispersion is investigated. For 1-THz bandwidth systems, the Q factor improvement is reduced from 10.9 to 1.5 dB by introducing PMD of 0.05 ps/√km.
Rumor has drawn much of the attention of researchers, considering its importance and influence, as well as its complexity. Under different circumstances, the process and results of rumor spreading are also different. The method of agent-based modeling is considered a good way to look into the process of rumor propagation. In this study, we put the theme under the circumstances of online social networks...
Cooperation among wireless nodes has been extensively studied in literals mainly used as data relaying mechanisms, however, it has been less exploited from control plane perspective to prevent undesirable transmission consequences such as data collisions.In this work, we investigate control plane cooperation in multichannel wireless ad hoc networks and propose a multichannel MAC protocol named by...
CAM-MAC proposed recently is a well designed wireless multichannel MAC protocol. By cooperating with neighbor nodes and using relative time instead of absolute time, CAM-MAC performs better than most of other multichannel MACs and do not need global synchronization. The deficiency of CAM-MAC is that it has not broadcast mechanism and thus, fails to exploit the broadcast nature of wireless medium and...
Distance Measuring Equipment (DME) is one of the most useful navigation systems, and its performance such as stability and precision relates to the safety of an aircraft. As the electromagnetic environment of an aircraft is very complex, it is urgent to find out which kind of interference affects the DME seriously. This paper puts forward behavioral modeling to analyze the electromagnetic interference...
Unscented Kalman filter (UKF) based methods have been developed for the tracking of GPS L1 signal. Optimal Kalman filtering theory makes it possible to maintain locking with large Doppler frequency shift when the receiver works in high dynamic environment. A novel UKF based carrier tracking loop with high accurate tracking performance is put forward, where a frequency fast pull-in technology is performed...
Channel asymmetry and high fluctuation of channel conditions are two salient characteristics of wireless channels in mobile environments. Therefore, when using IEEE 802.11 devices in mobile environments such as vehicular networks, it is critical to have an effective rate adaptation scheme that can deal with these issues. In this paper, we propose a practical rate adaptation scheme called RAM (rate...
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