Current Status of Active Phased Array Antennas and Future Trends
Heinz-Peter Feldle IRS 2009
Hamburg 10 Sept. 2009
Overview
• Operational Requirements
• Current Status
• New Concepts and Technologies
• Conclusion
AESA-Radar Requirements
• Inertia free Beam Steering &
Control
• Independent Scan and Track
• Highly flexible Scan Strategy
• Nearly simultaneous different Modes
• Adaptive Beam Pattern Control on Receive
• Efficient Use of Radiated Energy
• Highly Modular Architecture
• High Reliability and Maintainability
• Low Life-Cycle Cost
• Reduction of Radar Cross Section
Active Electronically Scanning Array (AESA) Main Components
AESA
APS ACU Receiver Processor
• Radiating Elements
• Planks incl. T/R Modules
• Manifolds (RF, Control, DC Power)
• RF-Interfaces
• Antenna Control Unit incl.
Beam Steering Unit
• Power Supply Unit
• Antenna Frame incl. Cooling
• WAIM Sheet
Apr= A cosθ G = ( 4π A cosθ ) / λ² θ
θ
A APr
Active Array
AESA Radar Applications
Space SAR
Fighter Radar
Airborne SAR
Naval Radar
Air Defence Radar
Ground Based Radar
Operational Systems Demonstrators
Transmit/Receive (T/R) Module
Generic Architectures and Requirements
Common Leg Architecture In Line Architecture
Requirement for grating lobe free
scan region
Required Phase Difference between Radiating Elements necessary for E-scan
of Antenna Patterns
T/R Module Example
• Single channel T/R Module (common-leg architecture)
• RF performance:
– Tx Power > 39 dBm (8 watts) – Rx Gain > 28 dB
– NF < 2.9 dB
– Control ranges 0 to 31.5 dB, 0 to 360 ° – Resolutions 0.25 dB
2.8125 °
• Overall mass < 12.5 g
• Overall size 64.5 x 13.5 x 4.5 mm³
• T/R module is fully digitally controlled
• No tuning or rework
• Size compatible for 2D antenna grid
• Hermetically sealed multilayer LTCC hybrid
• Multi-paction, RF corona free design, radiation tested
T/R Module Production Microwave Factory
Stable and qualified production processes are the prerequisite for
high rate production with high yield and reproducible performance data
Emerging Technologies
Gallium Nitride (GaN) Semiconductors
GaN - Advantages vs. GaAs
• High energy bandgap (x 2.5)
• High breakdown field-strength (x 10)
• High RF power densities ( x 5 to 10) on small chip sizes
• Broadband amplifier applications (multi-octave design)
• High bias supply voltages
• High thermal conductivity (x 3 (GaN), x 8 (SiC))
• Radiation hardness
Emerging Technologies
SiGe /BiCMOS Semiconductors
Ref.: X. Guan et. al., 2004
• Complex RF and control functions on chip-level
• Highest integration level
• RF phase and amplitude setting in digital domain
• Prerequisite for digital beamforming
• Overall size and weight reduction
• Increase of MTBF
• Cost reduction
• Secure access for military applications tbd
RF Multifunktion Chip (GaAs)
Emerging Technologies
Conformal and Structural Integrated Antennas
Conformal antennas
Structural integrated antenna subsystems
Conventional m-scan antenna
planar
2D curved
3D curved
Jammer Suppression Adaptive Beamforming
Subarray configuration with multi-channel receivers
Advanced Radar Concepts
Distributed Antenna Arrays to increase field-of-view
Bi-/Multi-Static Radar - Silent duty
- Cooperative illumination and joint detection with friendly platforms
Conclusion
• Rapid progress in active phased array antennas (AESA) and related key technologies enables broad application (Radar/SAR and
comminication) in military and commercial products.
• Complex and highly integrated multifunction circuits on SiGe and BiCMOS will enable SW defined radar and broad access for a dual- use sensors.
• COTS products will support the reduction in complexity and cost.
Secure and long-term access have to be analyzed.
• Structural integrated and conformal antennas as well as adaptive beam forming will become a prerequisite for advanced applications.
• Integration of GaN RF power technology and continuous increase of processing power will enable wideband and multi-band antennas (multifunctional systems).
