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• DECIMETER RANGE GENERATOR

  A. N. Zikiy, A. S. Kochubey

  2021-07-18

  Abstract ▼

  The receiver's heterodyne and the transmitter's master oscillator are the most important
  components, as they determine their stability and range properties. In recent years, the Meteor
  plant has created a number of new voltage-controlled generator chips with high electrical parameters.
  However, the advertising materials of this company do not contain a number of parameters
  that are important from the point of view of the consumer. Therefore, the purpose of this work
  is to study the main characteristics of the generator, including those not declared by the supplier:
  the width of the signal spectrum, the average steepness of the modulation characteristic, the level
  of harmonics. The object of the study is the GUN382 microchip in a typical switching circuit.
  The results of an experimental study of a VCO operating in the 1200 MHz region are presented.
  The estimation of parasitic products in the spectrum of the output signal is given. Photos of the
  spectrum of the output signal showing a small width of the spectral line are presented. The modulation
  characteristics are measured when the control voltage and supply voltage change, and their
  average steepness is calculated. These data allow us to make reasonable requirements for the
  stability of the control and supply voltages. The results obtained can be used in receiving and
  transmitting equipment for communication, navigation, and electronic warfare. The article expands
  the idea of the line of generators of the Meteor plant, demonstrates their high electrical
  characteristics: operating frequency range 1200 ± 16 MHz; output power of at least 1 dBm; supply
  voltage + 5V; control voltage from 0 to 8 V; the level of the second and third harmonics does
  not exceed minus 22 dB in relation to the useful signal.

• IMPROVING THE EFFICIENCY OF HIGH-PERFORMANCE FREE SPACE OPTICAL COMMUNICATION CHANNELS IN VARIOUS WEATHER CONDITIONS

  S. V. Zhilin, V.V. Arkhipenko, Е.S. Basan, М.Y. Polenov

  114-126

  2025-08-01

  Abstract ▼

  A common problem of traditional radio communication channels - the lack of free frequencies,
  noise, low bandwidth, the need to obtain a license to use the frequency, the relative ease of hacking.
  Free space optical communication channels overcome these limitations, is one of the types of communication
  systems that use open space to transmit information carried by light - this points to the
  need for direct visibility of the transceivers. Due to the influence of various weather conditions, the
  light flux is subject to atmospheric attenuation. In this paper, a method to improve the efficiency of
  high-performance wireless optical communication channels in different weather conditions: clear
  sky, fog, rain and snow was investigated. The existing wireless optical communication technology, a
  dense multiplexing multiplexing (DWDM) system with one input and one output (SISO), was considered.
  And it was proposed to improve the existing system by applying multiple input/output (MIMO).
  An impact and attenuation analysis on the wireless optical network in different weather conditions was conducted. The study was based on the use of the Optisystem simulation software toolkit, which
  is used to emulate different weather conditions of attenuation in two types of systems. Models were
  developed for each of the optical communication systems studied. A comparison between SISO and
  MIMO systems is made in terms of quality factor under different weather conditions. The proposed
  system shows promising results in terms of performance and received signal quality. The transmission
  path length of the proposed system in dense fog conditions increases by 33.6%. The transmission
  path length of the proposed system in heavy rain increases by 63.89%. The transmission path
  length of the proposed system in heavy snow increases by 35,21%.