Naval Surveillance Multi-beam Active Phased Array Radar (MAARS)

Naval Surveillance Multi-beam Active Phased Array Radar (MAARS)

MAARS

MAARS purpose: MAARS is multimode C-band acquisition radar for surveillance and weapon assignment. It perform automatic detection, track initiation and tracking of surface and air targets. Due to its modular design it can easily be adapted to a customer's range, resolution and accuracy requirements using existing components. Due to flexible communication interfaces to the combat system or when netted to other sensors, MAARS is suitable for integration with a track management system. The system has multi-beam scanning strategies to satisfy the special requirements of stand-alone radars for corvettes, patrol vessels, minesweepers, minehunters or as the self defense radar on frigates. Specific radar applications are sea skimmer detection with target assignment for close-in weapon systems.

MAARS most important features are: 4D air surveillance Digital beamforming of 12 simultaneous receiving beams with electronic stabilization Automatic and simultaneous detection and tracking (track-while scan) of: air and surface targets fast supersonic missiles sea skimmers, even in heavy sea clutter pop-up targets (e.g. helicopters) Fast target alarm for directly incoming targets Effective suppression of sea, rain, ground clutter and chaff Flexible adaptation of volumetric scanning and waveforms to the various radar tasks with scenario and environment-adapted operational modes Doppler processing - (MTD) Doppler Filter Bank for sea, rain and land clutter suppression with radial velocity measuring Separate air and surface target channels, each with adaptive detection thresholds Calculation of the required target data and determination of target type High ECM resistance Built-in test equipment (BITE) for on-line checks and to facilitate fault localization

ECCM characteristics of the MAARS are based on: Low antenna side lobe levels High angular resolution in azimuth against main lobe jamming Pulse compression for suppression of broadband pulse jammers Pulse-pulse and burst-to-burst agility for: radar frequency pulse repetition frequency pulse length signal coding to reduce deception jamming Pseudo-random frequency selection over the frequency band to counter spot jammers MTD processing to improve signal-to-clutter ratio and reduce the effects of chaff Jam detector for continuously monitoring the RF environment to provide information on jamming activity Adaptive Doppler-selective CFAR Automatic jammer avoidance circuit (AJAC) to select the least jammed frequencies Сoherent sidelobe cancellation (CSLC) and sidelobe blanking (SLB)

MAARS configuration Active Phase Array Antenna with digital beamformer, signal and data processor IFF antenna Antenna servo unit with slip-ring and rotary joint Operating console (option) Power supplies unit Control unit

Technical Characteristics 1. Frequency band C-band (NATO G-band) 2. Elevation coverage up to 70 (depending on operational mode) 3. Height coverage up to 20 km 4. Operational modes: - Extended Long Range mode instrumental range up to 200 km - Long Range mode instrumental range up to 150 km - Medium Range mode instrumental range up to 100 km - Short Range modes instrumental range up to 60 km 5. Rotation speed 12; 30; 60 r.p.m., selectable 6. Beam width (at -3dB): - Vertical (elevation) θ ε 5.7 - Horizontal θ β 1.6 7. Number of elevation phased array beams for reception - 12

Typical Detection Ranges Operational modes Extended Long Range ε 6 0 Long Range ε 30 0 Medium Range ε 70 0 Short Range ε 70 0 Antenna rotation time 5 sec 5 sec 2 sec 1 sec RCS Detection range for PD =0.5; PF = 10-6 interference-free conditions D, km 4 mm/h rain length=60 km 10 mm/h rain length=30 km bomber σ =10 m 2 165 148 130 surface target (frigate) Radio horizon under normal refraction; 200 km under superrefraction missile σ =0,03 m 2 27 24 21 fighter σ =2 m 2 100 89 80 attack aircraft σ =5 m 2 120 107 95 bomber σ =10 m 2 140 123 110 surface target (frigate) Radio horizon under normal refraction; 150 km under superrefraction missile σ =0,03 m 2 23 20 18 fighter σ =2 m 2 70 63 55 attack aircraft σ =5 m 2 85 75 65 surface target (frigate) Radio horizon under normal refraction; 100 km under superrefraction missile σ =0,03 m 2 20 18 17 fighter σ =2 m 2 50 45 40 surface target (frigate) Radio horizon under normal refraction; 60 km under superrefraction

Coverage Diagram For Low-Flying Target Antenna height = 15 m Missile σ =0,03 m 2 Fighter σ =2 m 2

Block diagram MAARS Radiator 1 Antenna system (main channels) Beamformer Signal Processing Unit Radiator 64 Radiator 1 Radiator 64 Rad.1 Horizontal beamforming unit (BFU1) Horizontal beamforming unit (BFU24) BFU 25 (SLC1) SLC Antenna 1 Transmitter module 1 Receiver module 1 Transmitter module 24 Receiver module 24 Receiver Unit 25 F S control test F IF FG1, FG2 F S control test F IF control test FG1, FG2 FIF F S FG1 FG1 Fsampl FClock Vertical Beamforming unit (BFU1) LO power divider G1 LO power divider 2 Exciter FIF FIF FIF SLC1 FIF SLC2 FSampl,FClock ADC ADC ADC ADC Control& Synchroniz. FS,FCl FS,FCl FS,FCl FS,FCl Control and test unit Synchronizer Stabilization processor I1 Q1 I24 Q24 ISLC1 QSLC1 ISLC2 QSLC2 Control Sign. Calibration processor Multi-Channel Dj Beamformer Unit IB1 QB1 IB12 QB12 IBnk, QBnk Synchronization, control and calibration unit Interface unit 12-Channel Side-lobe canceller IB1' QB1' IB12' QB12' Datagramms Testing Infomation Navigation Information Optimal Filter 1 Optimal Filter 12 Target trajectory detector Interface unit Noncogerent Detector1 Cogerent Detector1 Noncogerent Detector 12 Cogerent Detector 12 Data Processing Unit Tracking filters Target recognition Management and control unit Gateway, BIT Processor Control Processor Dj Distance and angle coordinates measuring unit Target coordinates and parameters of movement Cooling Unit Ethernet to CMS Navigation Information Heading sensor g Azimuth servo-drive g Rad.4 Rad.1 Rad.4 Test Rad. BFU 26 (SLC2) Microwave switch SLC Antenna 2 Testing Unit F S test Receiver Unit 26 Receiver Unit 27 FG1, FG2 control test FIF FG1, FG2 control test FIF FG1, FG2 test Dj Phases distribution processor Cos aу N λ, Dj Power unit 1 + 27 V, +5 V, -5 V Power unit DC/DC Power unit 6 +27 V Power unit 7 =280 V Sleep ring 50 Hz 220 V Control signals Power Unit + Cervo Unit 50 Hz 220 V Att F S test PDU 50 Hz 220 V Rad.1 Rad.N IFF Antenna IFF Unit control test S IFF D IFF to power supply unit 2-Channel Rotary joint IFF

Multibeam Receive Pattern 0-5 -10-15 -20-25 -30-15 -5 5 15 25 35 45 55 65 75 Elevation above horizon, deg.

db 36 Transmit pattern for Short and Medium range mode 30 24 18 12 6 0-6 -10 0 10 20 30 40 50 60 70 Elevation above horizon, deg.

db 36 Transmit pattern for Long range mode 30 24 18 12 6 0-6 -10 0 10 20 30 40 50 60 70 Elevation above horizon, deg.

Active Phased Array Antenna (APAA) Characteristics 24 radiating strip-line rows 24 transmit modules with GaN amplifiers 24 receive modules Shape and number of beams are programmable Electronic stabilization of the antenna beam Elevation angle is determined using monopulse techniques

Antenna Assembly General Drawing Front View Side View

Horizontal beamforming unit with radiators

VSWR VSWR for the radiated aperture 4 3 5.2GHz 5.525GHz 5.85GHz 2 1 0 10 20 30 40 50 60 THETA, deg

Antenna Assembly General Drawing Rear View

Radars Summary Performance MAARS XTAR-3D/L EADS TRS-3D Thales SMART-SMk2 Saab Sea Giraffe AMB Thales MRR-3D NG Bandwidth (NATO) G Band X Band G Band E/F-Band G Band G Band Instrumented range 60/100/150/200 km 50/75 km 200 km 150/250 km 30/60/100/180 km 180 km Scan rate 12/30/60 rpm 30/15 rpm 30/60 rpm 27/13.5 rpm 30/60 rpm 10/30 rpm Elevation coverage 16/30/70 > 50 55 /70 70 70 70 Beamwidtn (Az-El) 1.6-5.7 1.8-6 1.8-8 2-6 2-7 2 - Accuracy (Az-El) 0.2-0.4 0.3-0.4 0.3-0.6 0.3-0.6 0.2-0.6 0.3 - Elevation receive pattern Multibeam with digital beamforming Multibeam with digital beamforming Elevation scanning Multibeam with digital beamforming Multibeam with digital beamforming Number of beams up to 12 up to 12 up to 12 up to 12 Transmitter type Transistor power amplifier in each of phased array rows Mini travellingwave tube (TWT) in each of phased array rows Elevation scanning Klystron amplifier Vacuum tube TWT Vacuum tube Cooling type Air self-contained Air self-contained Liquid Liquid Air - Stabilization Electronic Electronic / mechanical Electronic / mechanical Electronic Electronic Electronic Rotary drive Antenna weight/ Under deck devices weight Direct drive 850 kg/ 280 kg 550 kg 600kg/ 2100 kg 1150kg/ 860 kg 660 kg/ 1270 kg Consumed power 10 kva 27.5 kva 35 kva - - -