Modernization of 5N84 (5N84A) RADARS

Performance characteristics of 5N84 (5N84А)

Radar before and after modernization



Performance characteristics of 5N84 (5N84А) Radar

before modernization

after modernization


Operation frequency band, МHz




Coordinates to be measured




Detection zone of target with Effective Reflective Surface (ERS) = 1m2 with Р=0,5




min range

2,7 km


Н=100 m

30 km

37 km


Н=500 m

85 km

105 km


Н=1000 m

110 km

130 km


Н=3000 m

185 km

220 km


Н=10 000 m

290 km

340 km


Н=20 000 m

380 km

450 km


max range to target with ERS =2,5m2 with Р=0,5

400 km

480 km


Coordinates measurement accuracy





1000 m

270 m











3500 m

1600 m




Transmitter pulse power                         

700 КВт

8-16 КВт


Jamming immunity                   





Against active noise jamming




Operating frequency retuning

Manual retuning,

4 fixed frequencies

Jammed environmental automatic monitoring and operating frequency automatic adaptive retuning pitch 0,2 МHz within band 160-200 МHz


Wide dynamic band of receiver and signal digital processing unit

18 dB

95 dB


Additional extension (by 32 dB) of dynamic range due to Automatic Gain Control (AGC)

15 dB

32 dB



Against passive jamming





Terrain echo suppression ratio

17 dB

more 40 dB



Moving Target Indication (MTI) operation zone

0-300 km,

manual setting

0-500 km,

adaptive MTI, jamming map



Against asynchronous, chaotic and pulse-responsive jamming

10 time

total suppression


Radio-altimeter control: (provided that altimeter extractor available)



Control mode



Number of controllable altimeters

up to 4


Target detection, path shaping




Number of marks per one rotation


up to 1000


Number of paths

up to 150


Operating conditions





from – 40ºС to +50ºС

from – 40ºС to +50ºС


relative humidity

up to 95%

up to 95%


Max height above sea level

2500 m

2500 m


Warm-up time

8 min.

3 min. (electrical mains)


Consumed power

60   kW

up to 40 kW

І. Particularities of 5N84 (5N84А) Radar modernization

Purpose of 5N84 (5N84А) Radar modernization:

  • Enhancement of tactical and technical capabilities and combat performance characteristics of existing 5N84 (5N84А) Radars;
  • Prolongation of Radar service life;
  • Reducing of operation cost and also reducing of cost and time required for maintenance and repair.

Modernization to 5N84M (5N84AМ) Radar gives an opportunity to get new Radar which includes:

  • Supply of a new Cabin fitted with up-to-date digital and solid state equipment, Remote Automated Workstation, power generators, SPTA set, and operating documentation;
  • Antenna-Mast System on semi-trailer ANP-1 (after repair of antenna-mast system and modernization of some assemblies and units);
  • Supply of two power supply systems 380V, 50 Hz with power no more 85 kW with the automatic switching system (ТОЕ.240.80.000);

Modernization of Radar includes:

- Installation of new installation kit instead of out-of-date equipment based on electro-vacuum tubes, old-fashion semiconductors, etc.

New equipment includes:

  • Solid-state transmitter.
  • Solid-state receiver, included.
  • Digital processing and synchronization unit (including MTI system) with characteristics as follows.
  • Operator’s computer-aided workplace;
  • Operator’s remote computer-aided workplace with remote control;
  • Computerized air conditioning control system;
  • Power supply and lighting distribution unit;
  • Fire-fighting system;
  • Operation-command communication system;
  • Switchboard;

2. Repair of antenna-mast system includes installation of up-to-date, reliable and efficient assemblies and units:

  • rotation motor М 3АА 180L;
  • HF feeder (HF cable);
  • slip ring;
  • irradiator.

The following equipment can be supplied as options:

  • information documenting system;
  • simulator;
  • 4-channel automatic compensator

Advantages of modernized 5N84М (5N84АМ) Radar

Installation of up-to-date radio-electronic elements and software significantly enhanced the tactical and technical characteristics, as well as combat performance characteristics of modernized radar 5N84М (5N84АМ), in particular:

Jamming immunity which is provided due to twice enhancement (comparing to old radar) of emitting signal energy, receiver dynamic range which is not less 100 dB and use of high-performance digital filter.

Installation kit for modernization of Radar includes digital signal processing unit which performs all signal formation functions and signal processing, including Moving Target Indication (MTI) and remote computer-aided operator workplace which performs trace signal and data processing functions;

Reliability which is provided due to installation of up-to-date radio-electronic components, new engineering solutions, and reduction of equipment volume. Meantime between failures (MTBF) of equipment constitutes 5000 hours that exceeds by 100 time performance characteristics of old-fashioned radar.

Repairbility which is provided due to block-modular configuration, technological effectiveness, accessibility and ease maintenance. Modernized Radar is equipped with total built-in self-diagnostic facilities and technical status indication detailed up to plug-in block or module, and transmitter – up to separate transistor. Repair is done by replacement of faulty modules. Therefore, recovery time of faulty equipment does not exceed 30 minutes that is several times higher than characteristics of old-fashioned radar.

Survivability which is provided due to reduced number of structural units of Radar, considerable reduction of cabling (only power supply cable, antenna-feeder path and four-core communication cable to link with remote computer-aided workplace remain after modernization), enhancement of protection system effectiveness against anti-radar rockets. Possibility to use the up-to-date radar data collection and transmission systems, elimination of a man-operator involved in this process and extended range of radar data transmission to users (Command Post, Antiaircraft Missile Defence Force and Fighting Aviation) highly increased the Survivability of Air Defence Force in total.

Electro-magnetic compatibility of modernized Radar is provided by Automatic Frequency Control (AFC) within Radar operating frequency band and minimally lowest level of its own out-of-band emission.

The main advantage of modernized Radar consists in total computerized process of signal processing, targets detection and data output. As all processes are handled completely in automatic mode (without operator’s intervention), radar maintenance is reduced up to a number of operators and excludes errors that can be caused by a man-operator during combat operation.


А. Purpose

The ground mobile 5N84М (5N84АМ) Radar is designed for automatic detection of the targets, determination of target current coordinates (azimuth and range), and automatic tracking of trajectories of the air objects movement.

5N84М (5N84АМ) Radar performs the following basic functions:

  • detection, display and automatic determination of coordinates, azimuth and range of Air Objects (AO);
  • automatic snapping and tracking of AO routes, analysis of parameters of their movement;
  • receipt, display and processing of information from similar radar or from radar equipped with A-1000М extractor, and formation of routes;
  • automatic control of Radio Altimeter (PRV) equipped with A-1000Н extractors, analysis of AO altitude coordinates;
  • automatic radar information transmission via telephone channel to the user;
  • possibility of non-computerized ("manual") reading of radar information using digital data of AO cards in coordinates "azimuth - range" or in square of Uniform Air Defense Grid in non-computerized groupings;
  • radar information record;
  • technical condition automatic test and diagnostics of Radar basic devices.

Based on radar 5N84M (5N84AM) can also be provided a control point (command center) of the first level.
Volume and a list of specific functions performed, the composition of individual software and hardware may vary depending on the configuration of units and the embodiment of the radar.

B. Jamming protection of 5N84М (5N84АМ) Radar

5N84М (5N84АМ) Radar has effective protection against the following kinds of jamming:

  • pulse noise;
  • passive jamming;
  • active noise jamming (АNJ).

Pulse noise of various kind suppressed completely during digital signal processing.

Protection against passive jamming is provided by MTI adaptive digital system and generation of jamming map.
Parameters of MTI adaptive system:

  • operation range  0 – 500 km;
  • terrain echo suppression ratio  > 40 dB.

Protection against active noise jamming is provided by:

  • automatic monitoring of jamming situation and displaying results to operator workplace;
  • radar operating frequency tuning with spacing 0.125 MHz;
  • wide dynamic range of receiver and digital signal processing equal to 105 dB;
  • additional expansion of dynamic range by 32 dB due to AGC.

B. Jamming protection of 5N84М (5N84АМ) Radar

For evident representation of jamming situation on the operator workplace screen (Operator Computer-Aided Workplace), in addition to echo - signal, the “noise path” is displayed in the form of irregular-shaped circular noise lines on variable range. Range of “noise path” displaying will go down as soon as noise (jamming) level is increased at the receiver input and vice versa. Blind spots are displayed in the event of jamming available from certain directions.
As a result, «noise path» shows to the operator relative variation of surveillance range jammed by active noise. By changing radar operating frequency, the operator can select optimal value within minimal reduction of surveillance range.

C. Performance characteristics of 5N84M (5N84АМ) Radar

Radar is powered from electrical mains, 3-phase, alternating voltage 380V, 50Hz, or from power generators.

  • Power consumption  <40 KW;
  • Warm-up time: from mains 3 min;

from power generator 3–5 min.

The radar can operate at any time of the day, in environmental temperature variation from –40 to +50°С (at wind speed up to 30 km/s) and influence of atmospheric precipitations.

Reception of information from other radars, as well as transmission of radar information to Remote Computer-Aided Workplace and to Users is done via telephone link modems at speed 9600 bit/s via ASTERIX protocol.

Radar can be transported on the roads category 4 and 5 at speed 25–40 km/h, on roads category 1, 3 – at speed 40-60 km/h.

D. General Structural Layout of 5N84M (5N84АМ) Radar

Structure of 5N84M (5N84АМ) Radar includes:

  • Apparatus Cabin – Trailer 1, fitted with main radar electronic equipment, Remote Computer-Aided Workstation, two power supply generators, individual spare parts kit, set of operating manuals;        
  • Antenna-Mast System (АМS) with Antenna-Feeder System (АFS) (for 5N84AM - trailer 2);
  • Set of cabling.

Remote Computer-Aided Workplace can be brought away from Apparatus Cabin and installed in Command Post. Remote Computer-Aided Workplace is equipped with all necessary communication and data exchange facilities. List of such communication facilities is to be agreed upon with the Customer.
Distance of Remote Computer-Aided Workplace is limited by length of communication cable (up to 500 m).

E. Structure

5N84M (5N84АМ) Radar incorporates the following functional systems:

  1. Transmitting System (cabinet УИ, probing signal formation sub-unit);
  2. Antenna-Feeder System (units 154, 254, HF feeders, Antenna-Mast System, T50/75 matching transformer, band-pass HF filter, coupler);
  3. Receiving System (HF amplifier, Main Channel Receiver, Digital Receiver, Digital Signal Processing and Synchronization Unit);
  4. Processing, Displaying and Data Output System (DSPSU, Operator Computer-Aided Workplace, Remote Computer-Aided Workplace, modems);
  5. Self-test and diagnostics system;
  6. Power Supply System including Power Station (two power generators), isolating transformer and switchboard of Apparatus Cabin;
  7. Antenna rotation, tilt, rise and lowering system (units 29, 31М, regulator of rotation, winch);
  8. Communication system;
  9. Air conditioning control system.

The above-stated division into systems is conditional, as separate devices participate in operation of several systems (for example, unit UDPS), and separate elements are structurally placed in other systems.

The transmitting system forms probing pulses (PP), emitted by antenna-feeder system (АFS). Parameters of emitted signals (frequency, structure, power) are set by the operator on Digital Signal Processing and Synchronization Unit (DSPSU) unit of which directly operates work of transmitting system. Polyplexer provides an outcome of transmitting and receive systems and switching of AFS to output of the transmitter or to input of the receiver.

Antenna-feeding system (АFS) carries out the functions on coordination of elements of antenna-feeding path, channeling and distribution of energy from transmitting system to radiators, formation of the directivity diagram of appointed kind and direct radiation of electromagnetic energy in space. At receiving of the reflected signals by radiators, they are summarized in a feeding path, and go to input of receiving system through polyplexer. Radar antenna system is made as the parabolic aerial of mirror type with dimensions of a mirror 32´11 m.

In receiving system the reflected echo – signals are amplified in low-noise HF amplifier, are transferred to intermediate frequency, are transformed to figures in the unit of the digital receiver and transferred for processing in Digital Signal Processing and Synchronization Unit (DSPSU).

All further processing on clearing a signal from noise, jamming of various kind, selection of the moving targets, detection of target signals and definition of their coordinates and movement parameters are carried out by processor of the unit of digital processing and synchronization (Radar processor) with use of special algorithms.
The system of display, processing and delivery of RE consists of operator workplace (AWP-О), remote OWP (AWP-R), Digital Signal Processing and Synchronization Unit (DSPSU) and modems. Processor of UDPS carries out the functions of control on formation of a probing signal, processing of the received radar-tracking signal, control on switching request for the state belonging and processing of the ground radio interrogator signals, and functions of control on displaying of the information on monitor of AWP-O and processing of the commands entered by operator. Structurally, Digital Signal Processing and Synchronization Unit (DSPSU) is placed in board of AWP-O.

On АWP-O there are placed the panels of switching of AWP, control on rotation and inclination of the antenna, manipulator, keyboard and board AKOS are placed.

Remote workplace AWP-R can be taken out from apparatus cabin to command point (CP). Delivery of the information on AWP-R from Digital Signal Processing and Synchronization Unit is organized through the modem channel.

On АWP-R the following missions can be also carried out:

  • receiving and processing of RE from another similar radar and formation of the common route;
  • automated control on radio altimeter and a binding of altitude to plane coordinates of AO.
  • delivery of RE to the user (on CP);
  • documenting of the radar information and the basic operations of AWP-R operator.

For decision of the specified tasks in AWP-R, except for unit of processor and monitor, there are 2-5 modems and storages placed on hard and flexible disks.
Information exchange with additional sources and the user is carried out through standard telephone connection channels with pass band of 300-3400 Hz with use of modems.

The antenna rotation system of (ARS) provides:

  • smooth start-up and rotation of Radar antenna on azimuth with the speed appointed by the operator;
  • formation of voltages of the synchronous–tracking drive (STD) for delivery the information about antenna angular position in UDPS;
  • formation of voltage of STD for control on synchronous rotation of GRI;
  • rising and lowering of the antenna at deploying and displacing.

The monitoring and diagnostics system carries out the following basic functions:

  • control on synchronization signals;
  • control and diagnostics on transmitting system elements;
  • control on receiving system;
  • control on processing of radar-tracking signal over the basic stages;
  • testing and control on serviceability of automated workplace AWP;
  • control on receiving and delivery of information.

The power supply system consists of diesel power station (DPS) and power distribution board (PDB) mounted in apparatus cabin.
In structure of power station there are two units of power supply, dividing transformer 380/220V, switching and other equipment. Power supply of the equipment is carried out by three-phase voltage of 220V/50Hz with isolated neutral. The voltage of external network can make 380 or 220V with grounded or isolated neutral. Power supply of automated workplace is carried out through sources of a uninterrupted power supply (UPS)..

The communication system is formed by the equipment of command–operative communication AKOC-1 installed on workplaces. Equipment AKOC-1 provides loud-speaking and telephone communication with persons of combat crew and command points. If necessary (at organization of guidance point), in corresponding variant of a completeness, additionally it can be installed the control system on radio stations for communication with aircraft crews.

After modernization of 5N84 and 5N84A radars, the 5N84M (5N84AM) Radar consists of two main units:
  • Apparatus Cabin (Shelter) – new;
  • Antenna-Mast System on trailer AnP-1 after modernization the 5N84AM Radar.

А. Equipment structure

Structurally the equipment of station consists of the following separate units and elements:

  • Antenna;
  • HF slip ring;
  • HF power divider;
  • unit of preliminary pulse amplifier BIU1, 1 kW;
  • unit of output pulse amplifiers BIU1, 2 kW;
  • adder unit;
  • switching unit;
  • control unit;
  • power supply units;
  • fans;
  • filter of power supply network;
  • directional coupler;
  • matching transformer T50/75;
  • HF bandwidth filter;
  • Low-noise HF (UHF) amplifier in switching unit of pulse amplifier cabinet;
  • Receiver and probing signal formation unit;
  • Operator computer-aided workplace (АWP-О) includes:
  • digital receiver unit;
  • digital signal processing unit;•monitor, keyboard, manipulator;
  • rotation control panel;
  • communication equipment AKOC;
  • modem;
  • UPS with power switchboard;
  • Remote computer-aided workplace includes:
  • processing unit;
  • monitor, keyboard, manipulator;
  • stores on hard and flexible disks;
  • source of uninterrupted power supply;
  • apparatus of communication AKOC;
  • modems;
  • UPS with power switchboard.
  • Rotation regulator (inverter);
  • Antenna rotation drive;
  • Selsyn unit – sensors;
  • Power distribution board (PDB);
  • Air conditioning control panel, two air conditioners, two heaters and fan;
  • Two power generators.

All equipment, except antenna-mast device, is placed in apparatus cabin.

B. Apparatus Cabin

  • The main equipment of Radar is installed in a new module. On the left wall of cabin there are two hatches. One hatch contains switchboard PShA with sockets for external connections. Another small hatch is for intake of external air into apparatus compartment during operation of exhaust fan.
  • On the back wall, to the right, there is socket 60А, 220V / 50Hz.
  • Fire extinguisher is fixed on the left shutter of back door under metal casing.
  • Two round hatches on the right wall of cabin. Upper hatch is for put-through cables from auxiliary channel antennas, the lower hatch is to connect HF cable from antenna-mast system. Hatches are sealed by rubber seals.
  • To the right, under module, there are two boxes with cable stakes and spare parts of trailer.
  • Two external units of air conditioner fixed on the front wall of module. Air outlet is with exhaust fan and temperature sensor is to the right.
  • Internal space of module is divided by wall into apparatus and operation compartments.
  • In apparatus compartment, along front wall there is cabinet of pulse power amplifier with main equipment of transmitter. On the right wall, behind the door, there are sub-units of receiver and probing pulse former.
  • Fan and cable boxes are fixed on the front wall of apparatus compartment. On the left wall there is rotation regulator (inverter) and two sockets to connect the portable electrical fan. Air conditioner is fixed above cable input. Two lights fixed on the ceiling.
  • Remote computer-aided workplace, operator computer-aided workplace and two armchairs are mounted in operation compartment.
  • Power switchboard, air conditioner unit and two sockets are mounted on the right wall. Cables installed in boxes attached to walls of the operation compartment.
  • Internal light panel, hanger and 1 kW electric heater are mounted on the back wall of operation compartment, above the door.
  • Lights are mounted on the ceiling.

C. Trailer with Antenna-Mast System

Trailer with Antenna-Mast System (for 5N84A Radar) represents a saddle trailer with antenna mounted on platform (basic antenna A0 and auxiliary antennas A1 … А4).