The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Sphere decoding (SD) is an efficient algorithm for Multiple-input Multiple-output (MIMO) digital communications. It has been showed to achieve near Maximum Likelihood (ML) performance with low complexity. However, the complexity of conventional SD algorithm is high under the specific environment. The performance and the computation complexity of SD algorithm is highly dependent on the initial choice...
We consider three kinds of minimum single source shortest path tree expansion problems. Given an undirected connected graph G = (V, E; w, c, b; s) with n vertexes, m edges and a positive constant H, w(e) is the length of edge e, c(e) is the capacity of edge e, b(e) is the unit cost to increase the capacity of edge e, H is a given capacity restriction value and s is a fixed vertex of G. For every edge...
Sphere decoding(SD)is an efficient algorithm which has been proposed in Multiple input Multiple output (MIMO) digital communication. Sphere decoding algorithm is based on the rule of maximum likelihood decoding algorithm, But SD algorithm does not like ML algorithm to retrieve all of the lattice. However, SD in some environment complexity is very high. The complexity of the SD is controlled by radius...
In this paper, we propose a new color image encryption and compression algorithm based on the DNA complementary rule and the Chinese remainder theorem, which combines the DNA complementary rule with quantum chaotic map. We use quantum chaotic map and DNA complementary rule to shuffle the color image and obtain the shuffled image, then Chinese remainder theorem from number theory is utilized to diffuse...
Finding the key nodes of the network is one of the most important applications in Community Detection. This paper combined Centrality, Cluster Coefficient and PageRank ideas, establish the measurement system of key nodes and according to the Kendal correlation coefficient of each index to modify the measurement system. Finally, using the Fagin algorithm to carry on the key nodes of the multidimensional...
In this paper, we mainly do the research about the non-overlapping community discovery. We use the GN algorithm and LP algorithm to test the randomly generated network, and compare the two algorithms in two layers, which are the time complexity level, and the static network's synchronization capability level. The simulation results show that the two algorithms are applicable to different scenes.
Lenstra-Lenstra-Lovász (LLL) is an effective lattice reduction algorithm in multi-input-multi-output (MIMO) system. The usage of LLL lattice reduction can significantly improve the performance of zero-forcing and successive interference cancellation decoders in MIMO communications. But for conventional single channel transmission, when the data streams go through poor channel condition, it usually...
Sphere Decoding (SD) algorithm was proposed to effectively find the Maximum Likelihood (ML) solution. However, the computational complexity of SD is still too high when SNR is low or the dimension of the problem is large. In this paper, we propose three improved schemes based on contraction factor to reduce the complexity of sphere decoding. In the proposed schemes, a factor was introduced for speeding...
The sphere decoding (SD) algorithm based on Schnorr-Euchner (S-E) strategy can reduce the complexity for multiple-input multiple-output (MIMO) systems to find the maximum likelihood (ML) solution by updating the search radius whenever a new lattice point was found. In this paper, we propose an improved scheme to reduce the complexity of sphere decoding. In the new method, a factor was introduced for...
In PCM/FM remote sensing receiving system, when the bit rate is above 1Mbps, the signal suffers frequency select fading, which causes the serious inter-symbol interference (ISI); power allowance can no longer guarantee the system quota. Besides signal reflection such as buildings, ground, mountains and atmospheric refraction eventually become the multipath interference signals. Thus an adaptive filter...
The orthogonal wavelet lowpassed filters coefficients with arbitrary length are constructed in this paper. When N=2k and N= 2k−1, the general analytic constructions of orthogonal wavelet filters are put forward, respectively. The famous Daubechies filter and many other wavelet filters are tested by the proposed novel method, which is very useful for wavelet theory research and many applications areas...
With the continuous expansion of the network size, some networks gradually present the characteristics of social networks, especially, scale-free networks. At present, some theoretical studies of scale-free networks are mainly based on simulated platforms. Based on this, the question that how we fast simulate a network model possessing scale-free effects and presenting related characteristics of realistic...
The unavoidable disadvantage of OFDM-larger peak-to-average-power ratio (PAPR), which can lead to high requirement for high power amplifier at transmitter and receiver, low efficiency of transmission, and so on. Tone Reservation (TR) is a technique designed to combat this problem by reserving a number of carriers (tones) in the frequency domain to generate a cancellation signal in the time domain...
Motivated by various network improvement models, we study the problem to add some new edges to satisfy the increasing information demand and keep the underlying structure of the networks unchanged. In this paper we propose the general network expansion problem on the spanning tree in graphs (GNEST), then we present the polynomial equivalence between the GNEST problem and the constrained minimum spanning...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.