Devising methods to synthesize discrete complex signals with required properties for application in modern information and communication systems

Information and communication systems (ICSs) must comply with increasingly stringent requirements to ensure the reliability and speed of information transmission, noise immunity, information security. This paper reports the methods to synthesize discrete complex cryptographic signals, underlying the construction of which are random (pseudo-random) processes; the methods for synthesizing characteristic discrete complex signals whose construction is based on using the nature of the multiplicative group of a finite field; the results of studying the properties of the specified signal systems. It is shown that the methods built provide a higher synthesis performance than known methods and make it possible to algorithmize the synthesis processes for the construction of software and hardware devices to form such signals. The win in the time when synthesizing nonlinear signals in finite fields using the devised method is, compared to the known method, for the period of 9,972 elements is 1,039.6 times. The proposed method for synthesizing the entire system of such signals, based on decimation operation, outperforms the known method of difference sets in performance. Thus, for a signal period of 2,380 elements, the win in time exceeds 28 times. It has also been shown that the application of such systems of complex signals could improve the efficiency indicators of modern ICSs. Thus, the imitation resistance of the system, when using complex discrete cryptographic signals with a signal period of 1,023 elements, is four orders of magnitude higher than when applying the linear signal classes (for example, M-sequences). For a signal period of 1,023 elements, the win (in terms of structural secrecy) when using the signal systems reported in this work exceeds 300 times at a period of 8,192, compared to the signals of the linear form (M-sequences)

Statistical properties of derived signal systems

The search for effective methods of synthesis of discrete signals (sequences) that correspond to the potentially possible limiting characteristics of correlation functions and possess the necessary correlation, structural, ensemble properties remains an urgent problem. The authors have proposed a method for the synthesis of derivatives of signal systems, for which orthogonal signals are used as the initial ones, and nonlinear discrete complex cryptographic signals (CS) are used as generating signals. The synthesis of the latter ones is based on the use of random (pseudo-random) processes, including algorithms for cryptographic information transformation. Derivative signals synthesized in this way have improved (in comparison with linear signal classes) ensemble and correlation properties, while the statistical properties of such signal systems remain unexplored. The paper presents the results of testing derived signal systems using the tests defined in FIPS PUB 140 and NIST 800-22. Analysis of the results obtained allows us to assert that the statistical properties of this class of derived signals satisfy the requirements for pseudo-random sequences: unpredictability, irreversibility, randomness, independence of symbols, etc. In essence, such signals do not differ from random sequences. The use of the proposed class of derived signals will improve the performance of signal reception noise immunity, information security and secrecy of the ICS functioning.

A REVIEW ARTICLE NON LINEAR SIGNAL NOISE MINIMIZATION

Commotion consistently debases the nature of ECG signal. ECG clamor expulsion is convoluted because of time changing nature of ECG signal. As the ECG signal is utilized for the essential conclusion and examination of heart ailments, a great nature of ECG signal is fundamental. An overview of different sorts of clamors tainting ECG signal and different methodologies dependent on Wavelet Transform, Fuzzy rationale, FIR sifting, Empirical Mode Decomposition utilized in de-noising the sign adequately are exhibited right now. The outcome tables looking at the exhibitions of different de-noising systems dependent on related parameters are incorporated

Nonlinearities in retinal bipolar cells shape the encoding of artificial and natural stimuli

The retina dissects the visual scene into parallel feature channels, and bipolar cells are speculated to play a key role in this signal separation. Yet, bipolar cells are traditionally viewed as simple, linear neurons. Here, using the salamander retina, we investigated the hypothesis of linear signal processing in bipolar cells by intracellularly recording their voltage signals under artificial and natural visual stimuli. We observed nonlinear representation of contrast and, unexpectedly, also nonlinear spatial integration in a sizable fraction of bipolar cells. Furthermore, linear receptive field models fail to describe responses of nonlinear bipolar cells to spatially structured artificial and natural stimuli. The nonlinear properties occur in the receptive field center and may be cell-type specific, with stronger effects in transient than sustained bipolar cells. Thus, our data suggest that nonlinear signal pooling starts earlier than previously thought, that is, before signal integration in bipolar cells.

Study on the Condition of Aging Vertebral Fracture Patients with Aging Based on Magnetic Resonance Imaging

The dissertation study was collected from 2015 to 2018 inpatients in our hospital for spinal surgery. For the 574 patients who met the inclusion criteria, they were divided into group A according to lumbar vertebrae QCT: lumbar vertebra CTQ ≤ 30 mg/cm3; group B: 30 mg/cm3 < waist QCT value ≤ 50 mg/cm3; group C: 50 mg/cm 3 < waist QCT value < 80 mg/cm3; Group D: 80 mg/cm3 ≤ waist QCT value < 120 mg/cm3. Among them, 142 patients in group A, 172 patients in group B, 177 patients in group C, and 83 patients in group D. MRI data from each group were reviewed and recorded for the presence or absence of a black linear signal on the STIR fat suppression image. The aim was to investigate whether bone density values were associated with the presence of a black linear signal of MRI STIR in osteoporotic vertebral compression fractures in order to provide a better reference for clinical treatment.