No abstract

No abstract

Hydrocarbon production in the Extreme North on unattended facilities is based on low earth orbit satellite (LEOS) systems for communications. Their information security can be improved by means of Identification-Friend-or-Foe (IFF) system for satellite. Authentication protocol based on modular codes(MC) makes it possible prior to communicating session to determine satellite status at minimum time consumptions. Such result is achieved due to parallel computations based on MC. However, MC can also detect and correct errors. Therefore, development of authentication protocol, where redundant MC are used for correction of errors occurring upon calculation of response to request from identification system, is an urgent problem. This work is aimed at improvement of fault tolerance of satellite identification system by means of the developed authentication protocol, where redundant MC are used for correction of errors occurring upon calculation of response to request from interrogator.

No abstract

The paper discusses adaptive filtering using Least Mean Square (LMS) and Recursive Least Square (RLS) algorithms. An algorithm for adjusting the coefficients of an adaptive digital filter in the Residue Number System and a procedure of developed algorithm applying depending on filter length and signal length are proposed. Mathematical modeling of the considered algorithms is performed. Examples are presented to demonstrate how the proposed technique can help the designer in the adjustment of the filter coefficients without the need for extensive trial-and-error procedures. The analysis of the denoising quality and computational complexity is made. Synthetic and real data (earthquake recording) were used while testing. The proposed algorithm surpasses the existing ones like LMS and RLS, and their modifications in a number of parameters: adaptation (denoising) quality, ease of implementation, execution time. The main difference between the developed algorithm is the sequential adaptation of each coefficient with zero error. In the known algorithms, the entire vector of coefficients is iteratively adapted, with some specified accuracy. The iterations (steps) number is determined by the input signal length for all algorithms.