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The modern development of mobile communications applied in remote sensing techniques requires continuous improvement of methods for transmitting information and developing new types of signals in order to achieve better resistance to interference, energy and structural secrecy of radiation, increase the efficiency of radio systems. These features have broad spectrum signals, the main advantages of which are: ensuring confidential transmission of information, extracting the signal from below the noise level, ensuring the reliability of the received information, even with a relatively small signal-to-noise ratio (SNR). Traditionally, the expansion of the spectrum of signals is done by multiplying the information signal by a code sequence, which is a random sequence, most often of binary symbols, formed by a determined law, but having the properties of a random sequence. Different classes of code sequences are known and used, which meet a number of mandatory requirements. However, they all have one or another drawback. An important reason for this is the lack of a universal mathematical apparatus through which to form a random sequence with the necessary structural complexity and correlation properties to ensure confidentiality in the transmission of information. With the emergence of a new direction in the development of communication technologies, based on the theory of dynamic chaos, there are alternative opportunities to expand the spectrum of signals. These are discrete chaotic signals, which, like pseudo-random sequences, are characterized by a quasi-continuous spectrum with uniform spectral density, with a steeply decreasing autocorrelation function and orthogonality. In the present work a structural scheme of a communication system between sensors is proposed, in which the spectrum of the information signal is expanded by a chaotic sequence. The noise immunity of the system is assessed by determining the probability of bit error rate (BER). The dependence of BER on SNR is studied. The connection with remote sensing could be review in the field wireless network using nodes. The methodology is tested in a simulation and in in-situ experiments. Some of the nodes are coated by new material and put into extreme conditions. The obtained results are analyzed and discussed.
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