Sequence Pairs Set Research Articles

Designs of Zero Correlation Zone Sequence Pair Set with Inter-Subset Uncorrelated Property

Designs of Zero Correlation Zone Sequence Pair Set with Inter-Subset Uncorrelated Property

Families of asymmetric sequence pair set with zero‐correlation zone via interleaved technique

An asymmetric zero-correlation zone (A-ZCZ) sequence pair set is a ZCZ sequence pair set consisting of multiple ZCZ sequence pair subsets. Two arbitrary sequence pairs which belong to different subsets should have a large zero cross-correlation zone (ZCCZ) in the A-ZCZ sequence pair set. Additionally, each subset is a typical ZCZ sequence pair set. The proposed A-ZCZ sequence pair sets can be generated based on interleaved technique from perfect sequence or perfect sequence pair of length P = Nmk with N ≥ 1, m ≥ 1, k > 1. The new A-ZCZ sequence pair sets are applied to quasi-synchronous code-division multiple-access (QS-CDMA) systems and it can hypothetically achieve larger ZCCZ than typical ZCZ sequence pair sets, as well as eliminating both multiple access and multipath interference in the QS-CDMA system.

Research on Periodic Punctured Binary Complementary Sequence Pair Set

A new discrete perfect signal named periodic punctured binary complementary sequence pair set is proposed. Several construction methods are proposed, such as using perfect punctured binary sequence pair or array pair, column orthogonal matrix, mate set interleaved operation, and periodic production methods etc. More periodic punctured binary complementary sequence pair sets could be generated through these methods. Research results show that it has wider existent scope and could be applied in engineering as a kind of perfect signal with good correlation properties.

Research of Zero Correlation Zone Sequence Pairs Set Construction Method Based on Interleaving Technique

Research of Zero Correlation Zone Sequence Pairs Set Construction Method Based on Interleaving Technique

Zero Correlation Zone Sequence Pair Sets for MIMO Radar

Inspired by recent advances in multiple-input multiple-output (MIMO) radar, we apply orthogonal phase coded waveforms to MIMO radar system in order to gain better range resolution and target direction finding performance. We provide and investigate a generalized MIMO radar system model using orthogonal phase coded waveforms. In addition, we slightly modify the system model to improve the system performance. Accordingly, we propose the concept and the design methodology for a set of ternary phase coded waveforms that is the optimized punctured zero correlation zone (ZCZ) sequence-pair set (ZCZPS). We also study the MIMO radar ambiguity function of the system using phase coded waveforms, based on which we analyze the properties of our proposed phase coded waveforms which show that better range resolution could be achieved. In the end, we apply our proposed codes to the two MIMO radar system models and simulate their target direction finding performances. The simulation results show that the first MIMO radar system model could obtain ideal target direction finding performance when the number of transmit antennas is equal to the number of receive antennas. The second MIMO radar system model is more complicated but could improve the direction finding performance of the system.

Phase Coded Waveform Design for Sonar Sensor Network

Since it is known that interference with each sonar sensor could be effectively reduced when waveforms are appropriately designed for a Sonar Sensor Network (SSN), we provide a set of new ternary codes called optimized punctured Zero Correlation Zone sequence-pair set (ZCZPS) and provide a method to construct such codes. We study the codes' properties especially using the ambiguity function to analyze the nature of the output of the matched filter. We apply our provided ternary codes to the SSN as pulse compression codes for narrowband pulse signals and simulate the target detection performance of the system. Comparing with the classical periodic Gold sequences, our codes could improve the system detection performance.

Construction of asymptotic optimal LCZ sequence pairs set

Best binary sequence pair exists in a lager scope than perfect binary sequence,for the sake of enlarging the address code selection of Quasi-Synchronization Code Division Multiple Access(QS-CDMA).Two methods of constructing sequence pairs set of asymptotic optimal Low Correlation Zone(LCZ) were proposed.A kind of asymptotic optimal LCZ sequence pairs set was constructed based on perfect binary sequence pair with modified Walsh sequences set(or m-sequence's cyclic shift sequences set) and a set generated by the cyclic shift sequences of a binary sequence pair with two-level periodic autocorrelation.The asymptotic optimal LCZ sequence pairs set constructed have more various parameters combinations.It can provide more choices for engineering application.

Radar Sensor Network Using a Set of New Ternary Codes: Theory and Application

In the radar sensor network (RSN), the interferences among different radar sensors can be effectively reduced when waveforms are properly designed. In this paper, we perform some theoretical studies on coexistence of phase coded waveforms in the RSN. We propose a new ternary codes-optimized punctured zero correlation zone sequence-pair set (ZCZPS)-and analyze their properties. Applying the new ternary codes and equal-gain combination technique to the RSN, we study the detection performance versus different numbers of radar sensors under the different conditions. The simulation results show that the RSN using our optimized punctured ZCZPS performs better than the RSN using the same number of common codes such as the Gold codes and much better than the single radar system no matter whether or not the Doppler shift is considered.

Research on Construction Method of ZCZ Sequence Pairs Set

Research on Construction Method of ZCZ Sequence Pairs Set

Optimized Punctured ZCZ Sequence-Pair Set: Design, Analysis, and Application to Radar System

Based on the zero correlation zone (ZCZ) concept, we present the definitions and properties of a set of new ternary codes, ZCZ sequence-Pair Set (ZCZPS), and propose a method to use the optimized punctured sequence-pair along with Hadamard matrix to construct an optimized punctured ZCZ sequence-pair set (OPZCZPS) which has ideal autocorrelation and cross-correlation properties in the zero correlation zone. Considering the moving target radar system, the correlation properties of the codes will not be severely affected when Doppler shift is not large. We apply the proposed codes as pulse compression codes to radar system and the simulation results show that optimized punctured ZCZ sequence-pairs outperform other conventional pulse compression codes, such as the well-known polyphase code--P4 code.

Detection of non-coding RNAs on the basis of predicted secondary structure formation free energy change

BackgroundNon-coding RNAs (ncRNAs) have a multitude of roles in the cell, many of which remain to be discovered. However, it is difficult to detect novel ncRNAs in biochemical screens. To advance biological knowledge, computational methods that can accurately detect ncRNAs in sequenced genomes are therefore desirable. The increasing number of genomic sequences provides a rich dataset for computational comparative sequence analysis and detection of novel ncRNAs.ResultsHere, Dynalign, a program for predicting secondary structures common to two RNA sequences on the basis of minimizing folding free energy change, is utilized as a computational ncRNA detection tool. The Dynalign-computed optimal total free energy change, which scores the structural alignment and the free energy change of folding into a common structure for two RNA sequences, is shown to be an effective measure for distinguishing ncRNA from randomized sequences. To make the classification as a ncRNA, the total free energy change of an input sequence pair can either be compared with the total free energy changes of a set of control sequence pairs, or be used in combination with sequence length and nucleotide frequencies as input to a classification support vector machine. The latter method is much faster, but slightly less sensitive at a given specificity. Additionally, the classification support vector machine method is shown to be sensitive and specific on genomic ncRNA screens of two different Escherichia coli and Salmonella typhi genome alignments, in which many ncRNAs are known. The Dynalign computational experiments are also compared with two other ncRNA detection programs, RNAz and QRNA.ConclusionThe Dynalign-based support vector machine method is more sensitive for known ncRNAs in the test genomic screens than RNAz and QRNA. Additionally, both Dynalign-based methods are more sensitive than RNAz and QRNA at low sequence pair identities. Dynalign can be used as a comparable or more accurate tool than RNAz or QRNA in genomic screens, especially for low-identity regions. Dynalign provides a method for discovering ncRNAs in sequenced genomes that other methods may not identify. Significant improvements in Dynalign runtime have also been achieved.

Novel Sequence Pair and Set with Three Zero Correlation Windows

In this paper, we present a set of sequence pairs which produce zero correlation windows not only in the middle part of the sum of aperiodic correlation functions, but also in the two terminal parts. We name it Ear Windows. In approximately synchronous CDMA communication system, this set of sequences is able to completely remove the inter-symbol interference (ISI) and multi-user interference (MUI) caused by the multipath effect if the maximum delay is shorter than the length of the Ear windows. In addition, it is also feasible in M-ary modulation. The intercede interference will be mitigated drastically.