Beijing Institute of Satellite Information Engineering
Beijing Institute of Satellite Information Engineering
Zhu K.,Nanjing University of Aeronautics and Astronautics |
Cheng Z.,Beijing Institute of Satellite Information Engineering |
Chen B.,Nanjing University of Aeronautics and Astronautics |
Wang R.,Nanjing University of Aeronautics and Astronautics
IEEE Wireless Communications and Networking Conference, WCNC | Year: 2017
Virtualization has been seen as one of the main evolution trends in future cellular networks which enables the decoupling of infrastructure from the services it provides. In this case, the roles of infrastructure providers (InPs) and mobile virtual network operators (MVNOs) can be logically separated and the resources of a base station owned by an InP can be transparently shared by multiple MVNOs, while each MVNO virtually owns the entire BS. Naturally, the issue of resource allocation arises. Specifically, the InP is required to abstract the physical resources into isolated slices for each MVNO who then allocates the resources within the slice to its subscribed users. In this paper, we aim to address this two-level hierarchical resource allocation problem while satisfying the requirements of efficient resource allocation, strict inter-slice isolation, and the ability of intra-slice customization. To this end, we propose a hierarchical combinatorial auction model, based on which a truthful and efficient resource allocation framework is provided. And we show by an illustrative example how the proposed model can be applied for wireless virtualization. Specifically, winner determination problems (WDPs) are formulated for the InP and MVNOs, and computationally tractable algorithms are proposed for solving these WDPs. Also, pricing schemes are proposed for ensuring the incentive compatibility. Note that the proposed model can be generalized for the virtualization of resources with more dimensions (e.g., power, antennas, etc.). © 2017 IEEE.
Zhang J.,Hefei University of Technology |
Li K.,Imperial College London |
Cong S.,Hefei University of Technology |
Wang H.,Beijing Institute of Satellite Information Engineering
Signal Processing | Year: 2017
The conventional quantum state tomography (QST) needs large number of measurements to reconstruct the quantum state. Thanks to the compressive sensing (CS) theory, one can recover a pure or nearly pure quantum state with an acceptable accuracy given much fewer number of measurements. However, most existing algorithms for CS based QST are rather slow and difficult to be implemented in practice. To fill the gap between the CS theory and practical QST, this paper firstly applies an improved Alternating Direction Multiplier Method (ADMM) combining with the Iterative Shrinkage-Thresholding Algorithm (ISTA), IST–ADMM for short, aiming at improving the efficiency of QST problem in particular with much lower number of measurements. The IST–ADMM avoids computing the inverse of large-scale matrix, reduces the computational time and required memory space. The computation complexity is reduced from O(d6) for least square (widely used in QST), and O(md4) for Fixed Point-ADMM in our previous work, to IST–ADMM's O(md2). The proposed algorithm makes it practical to reconstruct high dimensional quantum states provided fewer number of measurements. The simulations verify the superiority of the proposed algorithm, where it takes 3.13 minutes to reconstruct an 8-qubit density matrix with 96.17% accuracy, which is faster than many existing and our previous work. © 2017 Elsevier B.V.
Wang J.,Southwest University for Nationalities |
Wang J.,Beijing Institute of Satellite Information Engineering |
Wen X.-J.,Beijing Institute of Satellite Information Engineering |
Huang C.,Beijing Institute of Satellite Information Engineering |
And 3 more authors.
Frontiers of Information Technology and Electronic Engineering | Year: 2017
We study the optimal precoding for a full-duplex (FD) system, where one FD multi-antenna base station (BS) respectively transmits to and receives from two half-duplex single-antenna mobile users (MUs) on the same time slot and frequency band. At the FD BS, the received signal from the desired MU is severely affected by the extremely strong self-interference (SI) from its transmit antennas to the receive antennas. In the presence of residual SI after imperfect SI cancellation, the downlink transmission rate maximization problem subject to a targeted uplink rate is formulated as a non-convex optimization problem to characterize the achievable rate region for the considered system. Considering the case in which the SI channel is strongly correlated, the above problem is transformed into a convex problem by exploiting the rank-one property of the SI channel, which can be solved efficiently. Finally, numerical results validate the effectiveness of the proposed scheme. © 2017, Zhejiang University and Springer-Verlag GmbH Germany.
Jun L.,Northeastern University China |
Jingyu Y.,NDU of PLA |
Zijing C.,Beijing Institute of Satellite Information Engineering |
Mengyuan W.,Beijing Institute of Satellite Information Engineering
Chinese Journal of Electronics | Year: 2017
Catering to the public nature of Ad hoc network in open channel and data communication being easily eavesdropped, this paper proposed an antieavesdropping algorithm which is based on network coding. The algorithm is based on the RSA signature algorithm introducing the timestamp and homomorphic mechanism to detect tampering and replay attacks, as the basis for calculating safety, being used as one of measurement indicators in router by node safety to establish t pieces of routing entry. It generates encoding vectors by introducing the random number when the source node is encoded and the random number will be divided into n pieces. As long as the sink node receives t pieces of fragments, we can restore the original encoding vector and decode it. If the eavesdropper wiretaps are less than t, they can not get any meaningful information. It is designed for increasing the number of linearly independent coded packets.It can improve the decoding efficiency by adopting generational grouping strategy while being encoded. Simulation and theoretical analysis shows that the anti-eavesdropping algorithm based on network coding improves network performance and security by coding gain. © 2017 Chinese Institute of Electronics.
Zhang L.,University of Science and Technology Beijing |
Zhang F.-C.,University of Science and Technology Beijing |
Wang B.,Beijing Institute of Satellite Information Engineering
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013
Aiming to improve the performance of transmitted reference(TR) UWB system and mitigate external interference in multipath channel, time reversal(TiR) is employed. The BER performance of TR-UWB systems with and without TiR technology are investigated respectively, and the results imply that the SNR of TR-UWB system is improved about 10dB in multi-path channel with TiR pre-filter than that without TiR pre-filter whilst BER=1E-3. The impacts of the notch filter's parameters on performance of TiR TR-UWB system are investigated. The simulation results show that every increase of 528MHz in the width of notch filter causes 5dB degradation in the performance whilst the depth of notch filter has little influence on it. Finally, BER performance of this system with notch filter is studied in the case of MB-OFDM-UWB interference. Results indicate that with ultra-wideband notch filter technology, strong ultra-wideband interference within a bandwidth of 3×528MHz can be mitigated. For BER=1E-2, the signal-to-interference ratio(SIR) of TR-UWB improves 25dB with a notch filter comparing to that without a notch filter. The present work is expected to be useful for the design of the simple and advanced TR-UWB system. © 2013 Springer-Verlag Berlin Heidelberg.
Weibiao Z.,Beijing Institute of Satellite Information Engineering |
Tao D.,Beijing Institute of Satellite Information Engineering |
Xin W.,Beijing Institute of Satellite Information Engineering
Proceedings of 2016 IEEE Information Technology, Networking, Electronic and Automation Control Conference, ITNEC 2016 | Year: 2016
In order to solve crossover of lines in MMIC (Monolithic Microwave Integrated Circuits), a novel microstrip coupler has been presented. With a double-ring structure, the presented coupler achieves high isolation between adjacent ports. The size of coupler has been reduced by using an arc impedance transformer; Parameters influencing resonance loop and impedance matching of the coupler have been analyzed and the equations of theses parameters have been derived. Simulation, fabrication and measurement for the coupler have been done. Simulation of the relative bandwidth of reflectance, insertion loss and isolation is 18.61% (S11<-10dB), 7.31% (S12>-1dB) and 4.99% (S13<-15dB) respectively. Correspondingly measurement results is 17.94%,8.04% and 4.80%. Simulation and measurement results agree very well, which confirms the validity of the design. © 2016 IEEE.
Li H.-C.,Beijing Institute of Satellite Information Engineering |
Song H.-F.,Beijing Institute of Satellite Information Engineering
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011
The linear array CCD camera is the main sensor on the push-broom satellite. Because of the difference response among the CCD detectors, the striping noise is an obvious phenomenon in the remote sensing image along the scanning direction, which can seriously affect the image quality and quantitative application. The object of relative radiometric calibration is to eliminate them. As the state of satellite electronics varies from orbit to orbit, an automatic de-striping algorithm is needed that depends only on information that can be attained from the image data. There are many published techniques that are used to remove striping from images such as the histogram matching, histogram equalization, and Fourier transform filter methods. In order to decrease the effect we try to remove these stripes in CCD images using a relative radiometric correction algorithm based on the adaptive filtering pattern in this paper. Firstly, aiming at the characteristics of strip noise in push-broom scanner, the cause of strip noise formation is described. The suitable 1-D nonlinear filter is chosen to remove the obvious stripping based on the stripping distribution. Then, 1-D smoothing filtering is used to calculate the gain and offset coefficients. At last, the thin stripping is de-striped with the obtained coefficients. The final results indicate that the proposed method can effectively remove the stripping noise along the scanning direction effectively. Comparison of mean value and standard deviations obtained from the strip noise removed image by the proposed method and histogram equalization method suggested that the proposed method is evidently superior to the traditional histogram equalization method in preserving the image detail very well. The result of this study is applicable in striping removal of push-broom satellite's remote sensing data. © 2011 SPIE.
Li H.-C.,Beijing Institute of Satellite Information Engineering |
Hao S.-Y.,Beijing Institute of Satellite Information Engineering
Guangdian Gongcheng/Opto-Electronic Engineering | Year: 2011
Because of the difference response among the detectors in the pushbroom satellite, striping is an obvious phenomenon in the remote sensing image along the scanning direction. A relative radiometric correction algorithm is put forward based on the adaptive filtering pattern. Firstly, the suitable 1-D nonlinear filter is chosen to remove the obvious striping according to the image striping distribution. Then, the 1-D smoothing filter is used to calculate the gain and offset coefficients. At last, the thin stripping is destriped with the obtained coefficients. The comparison experiment proves that the algorithm can effectively improve the image quality, and remove the stripping along the scanning direction, at the same time it preserves the image detail.
Chen S.-S.,Beijing Institute of Satellite Information Engineering |
Liang Z.-G.,Beijing Institute of Satellite Information Engineering |
Zhang M.-Y.,Beijing Institute of Satellite Information Engineering
Xitong Fangzhen Xuebao / Journal of System Simulation | Year: 2014
The use of GPS receiver for high earth orbit (HEO) satellites which overcame the weak observation geometry from the earth could improve the orbit determination precision and also request high performance of receiver in weak signal processing. To lower the risk of engineering application, the simulation based on overall link analysis instead of geometrically visibility was needed. The simulation method estimated the GPS availability according to the signal power by link equation calculation and was developed by STK together with MATLAB, which made the result credible, reliable and flexible in theory and practice. Aimed at GEO application, the simulation result and the analysis for the large amount of available GPS number and proportion of side lobe signal in high sensitive receiver were proposed. And it is flexible for the proposed method to add the navigation constellation in order to be used for other navigation system receiver design.
Li H.,Beijing Institute of Satellite Information Engineering |
Hao S.,Beijing Institute of Satellite Information Engineering |
Zhu Q.,Beijing Institute of Satellite Information Engineering
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering | Year: 2011
A fast seamless mosaic algorithm for multiple remote sensing images was proposed to solve the problems of the high computation cost when mosaic processing and the obvious seam line existed in the mosaic result. Firstly, the original overlapping regions were determined according to the overlapping structure of the multi-chip CCD devices. Secondly, in order to reduce the computational burden, the original overlapping regions were decomposed into multi-resolution decomposition. Then the cross correlation matching method was used for the images mosaic, and the precise overlapping regions were obtained. At last, a new space interpolation mapping method was used to complete the histogram matching of overlapping regions, and the histogram look up table (LUT) was established to assign new values for the original image, which eliminated the mosaic seam caused by tone difference among the adjacent images. The experimental results show that this algorithm is practicable and can gain more satisfying mosaic images.