Search

Search Results

• EXPERIMENTAL STUDY OF A PROTECTIVE DEVICE

  А.V. Andrianov, D.Е. Gubarev, А.N. Zikiy, P.N. Zlaman

  263-270

  2025-07-31

  Abstract ▼

  The protective device (limiter) at the receiver input is an important component, as it ensures
  the safety of the receiver operation in conditions of receiving powerful signals. The results of an
  experimental study of a protective device in the 1-4 GHz band are presented. It is shown that the
  minimum bandwidth losses at a low power level do not exceed 0.63 dB, the maximum bandwidth
  losses are 1.23 dB. At an input power of 25 dBm, the protective device operates in a non-linear
  mode, therefore it creates harmonics of the input frequency. The experimental amplitudefrequency
  response (AFC) of the protective device, as well as amplitude characteristics at three
  frequencies are presented. The experiment to remove the frequency response was carried out on a
  vector analyzer of circuits. The experiment to remove the amplitude characteristics was carried
  out using a standard signal generator and a spectrum analyzer at three frequencies: 1 GHz;
  2 GHz; 4 GHz. Structurally, the protective device is a polycor substrate on which all elements
  except connectors are placed. The substrate is placed in a frame-type housing and closed with two
  sealed lids. Type III sockets according to GOST13317- 89 are used as connectors. A schematic
  diagram and a brief description of the design are given. The following main parameters have been
  achieved: losses do not exceed 1.23 dB in the operating frequency range from 1 to 4 GHz, the output signal power at a high input power level (f = 1 GHz; Rvh = 25 dBm) does not exceed
  12 dBm. The protective device is recommended to be used in the input circuits of communication
  receivers, navigation, radar and electronic warfare

• BALANCED MIXER

  А.N. Zikiy, P.N. Zlaman, А. V. Pomazanov

  2023-02-27

  Abstract ▼

  An experimental study of a balanced mixer based on 2A116A-1 diodes was carried out.
  Conversion losses were measured in the input frequency range of 2450 ± 45 MHz during down
  conversion to an intermediate frequency of 2125 MHz. Conversion loss does not exceed 20 dB in a
  narrow band of 2440±10 MHz. The amplitude characteristic of the mixer was taken, from which it
  can be seen that it is linear for input signals up to 0 dBm (1 mW). The dependence of conversion
  losses on the local oscillator power is studied. It is shown that the minimum losses are observed at
  a local oscillator power of 13 dBm (20 mW). The combination frequency spectrum at the mixer
  output does not contain parasitic conversion products above minus 50 dB with respect to the useful
  signal in the 100 MHz bandwidth. The mixer is recommended for use in receiving and transmitting
  equipment and measuring equipment. Comparison with other mixers shows a noticeable advantage
  - high selectivity in relation to out-of-band signals. This is achieved by applying two band
  pass filters and a low pass filter. Three filters were simulated in the Microwave Office software
  package. Models and amplitude-frequency characteristics of three filters from Microwave Office
  are given. The mixer is made in a frame-type case made of aluminum. It has two ceramic boards
  sized 24x30 mm (material 22xc). The method of manufacturing a printed circuit board pattern is
  thin-film technology. The case is closed by two tight covers. All three connectors are type
  IX GOST13317, socket.

• MODELING OF TWO MICROSTRIP FILTERS OF THE CENTIMETER RANGE

  A.N. Zikiy , P. N. Zlaman

  2021-01-19

  Abstract ▼

  Band-pass filters are an integral part of any radio equipment. They determine the selectivity of
  the receiver for all channels of reception. The aim of this work is to modelling two microstrip filters
  of the centimeter wave range. The object of study in this work are two microstrip filters at a frequency
  of 5.75 GHz and 4.6 GHz. Such filters can be used in the converter of the centimeter wave range
  as a signal and heterodyne filters. Two filters were simulated in the Microwave Office environment.
  The results are presented in the form of models of two filters and four amplitude-frequency characteristics.
  Given are the geometric dimensions of the filters, sufficient for their manufacture on material
  RT5870 of Rogers company. Filters have a bandwidth of 200 MHz and a loss in bandwidth of not
  more than 3 dB. Losses in the stop band for the signal filter were at least 45 dB, and at least 35 dB
  for the heterodyne filter, which is a very good result for a two-pole filter. Acceptable electrical parameters,
  small dimensions and moderate cost of manufacturing filters allows them to be widely used
  in professional and amateur radio equipment. To improve the manufacturability of manufacturing, a
  material with a low dielectric constant was selected. At the same time, gaps and tolerances on theaccuracy of their manufacture are acceptable. The design of the filters allows them to be easily
  integrated with other components of the converter: a low-noise amplifier, a mixer, an intermediate
  frequency amplifier, an amplifier in the local oscillator path.