autonomous wideband adaptive multifunctional antenna
TRANSCRIPT
Autonomous Wideband Adaptive
Multifunctional Antenna
Bringing Innovation to Military Communication
Systems
Presented by
Prof. Amit Mehta
Swansea University, UK
1
Layout
5G and IoT
Needs of Military communications
Adaptive Antennas (AA)
Case studies and applications
Conclusion
2
Rapid evolving communications
3
3G – Speech 4G – See5G – Touch
[Ref: Ericsson]
Exponential increase- devices interconnected
4
[Ref: Ericsson]
Internet of Things(IoT) / Smart City
5[Ref: NEC]
Internet of Military Things
6Base operations• situational awareness • boundary surveillance including harbour•energy management, etc
[Ref: cybercodetech]
Core component – connectivity
7[Ref: CSIS]
Military connectivity problem: much more severe than civilian
• Weak electromagnetic environments
• Jamming / EM Clutter / interference /Multipath
• Overheads of encryption
• Spectrum efficiency - Full sustained HD
• SWaP & Wide band operations
• Longer battery times and device ranges
• Autonomous system operations
8
Current antennas-majority
9
Restrictions of Omni antennas
• Transmit in all directions – enemy knows
• Multipath serious issues – communications ceases
• Power waste – battery loading
• Lower digital data rates
• Smaller ranges
• Interference-lower capacity
• More nodes / area required in sensor networks: Costly
• No axial patterns
• Limited bandwidth
10
Solution: Adaptive Antennas (AA)
Transmit in direction of interest only
High gain, longer ranges & lower transmit power
Multipath mitigation
Jamming avoidance
High throughput
11[Ref: Balanis]
Achieving Pattern Adaptability
• Phased array antennas
• Single element based systems
Phase Shifters
Antennas
ϕ ϕ ϕ ϕ
Power Distribution network
RF Source
Radiation
beam
RF Switch
RF Source
Antenna
Radiation
beam
12[Ref: Balanis]
Array vs single element (GNSS L1 band) – satellite navigation
Array Single element
16 element – large area size, 0.65 m2 One element - .2 m2 (4 times smaller)
Cost - £1000 Cost – £ 50 (20 times cheaper)
Weight 3x gms Weight x gms (3 times lighter)
Total RF loss 10 dB (feeding and phase shifters)
RF loss (3 dB) (over 75 % lower RF loss)
Complex signal processing – more power required
Simple and low power required
Big funding push to come up new innovative single element pattern adaptive designs
13
Initial academic work
• Prof. Mehta 2002 – UK
– Department of Health
• University of Illinois, USA around same time
– NASA project for distributed sensors for satellite applications
• University of California, USA 2005
– DARPA project
14
1515
2. A Mehta, D. Mirshekar-Syahkal and H. Nakano, “Beam adaptive single arm rectangular spiral antenna with switches,”
Microwaves, Antennas and Propagation, IEE Proceedings , vol.153, no.1, pp.13,18, Feb. 2006.
Shorted spiral antenna with four switches. Prototype shorted spiral for switching case 8 θmax and max and for sixteen switching cases
First major papers:
4 Shorting
switches
1
2
3
4O`
4
3 2 1
MEMS
Shorted – Hard wired
4 Shorting
switches
1
2
3
4O`
4
3 2 1
MEMS
Shorted – Hard wiredhard wired
Four shorting
pins
1. A. Mehta and D. Mirshekar-Syahkal, “Spiral antenna with adaptive radiation pattern under electronic control,” Antennas and
Propagation Society International Symposium, IEEE , vol. 1, pp. 843-846, 20-25 June, 2004.
16
And
3. Reconfigurable Scan-Beam Single-Arm Spiral Antenna Integrated With RF-MEMS Switches by Flaviis et al, IEEE Trans.,
Antennas Propagation Vol. 54, NO. 2, February 2006, pp. 455-463
Reconfigurable single-arm rectangular spiral antenna
integrated with four RF-MEMS switches.
Maximum beam direction in both
elevation and azimuth angles.
4. Integration of packaged RF MEMS switches with radiation pattern reconfigurable square spiral micro-strip
antennas by Bernhard et al , IEEE Trans., Antennas Propagation Vol. 54, NO. 2, February 2006, pp. 464-469
Case study: UK MoD funded workJuly 15 - Jan17
• Aims– Fully autonomous intelligent beam steering
system for locking on the strongest signal arrival direction
– Real time link optimization
– RF Switch based, cheap and fast (100 nanosecond)
– User don’t have to do anything
– Operating stack not disturbed: os independent
– Conformal
17
System architecture
18
Beam - steering in 4 quadrants
Directivity 7.81dBiat 2.45GHz
19
Laboratory measurements
Turn table
70cm
Horn antenna
AC
D
B
1.3m
HSLA beam due to A
Multipath signals
A C
D
B
Touch screen
(a). HSLA and Raspberry Pi
Switch control voltages
Power supply
WiFi Adaptor
(b). Raspberry Pi
(c). Experimental set-up 20
Transmitter
Interference
HSLA
Line of sight transmission and interference
Transmitter power: -27 dBm
HSLA gain: 8.94 dBi
Monopole Gain: 3 dBi
0 5 10 15 20
0
1
2
3
4
5
6
Magnitude of Interference (dBm)
Th
rou
gh
pu
t (M
bp
s)
HSLA Monopole Antenna
Monopole
antenna
TransmitterInterference
Test case outputs
• Intelligent link adaptation based on dynamic changing parameter-real time
• Autonomous system
• No disturbance with existing communications
• Future work: Power transmit and direction dynamic: Tx only in direction and to a fixed distance
22
Application - Satellite IoT Tracking
Semi-doughnut beam points high gain in right look up angles, lower EIRP / null other directionsAdjust pattern autonomously and continuously - accordingly to the look up angle
23
Application – jamming avoidance
24
3D pattern of patch antenna (Shell 50 cm)
Frequency: 2.45 GHz
Gain: 4.39 dBi
Beam steering Shell 50 cm)
Frequency: 2.45 GHz
Gain: 10.7 dBi
Application: Autonomous UAV swarm
25Working together: Each drone a sensor giving cue to each otherWorking independent or any other combination
Base station cellular architecture Autonomously Adapt to environmentBeam steering, jamming avoidance & auto power control would play important role
[Ref: US Airforce]
Application-last mile
26[Ref: UK MOD]
Swansea University’s Antenna and Smart City Lab- Amongst the UK best
27
Conclusion
• Modern electronic warfare would need autonomous (real time) adaptive wideband multifunctional antennas systems for
– Concreate jamming avoidance, multipath mitigation, longer ranges, lower cost for sensor network, autonomous distributed systems, longer battery, etc.
• Hence, great importance in defence and security applications
• Expect devices & systems out by 2020
28
29
Title ofpresentation
• Click to edit subtitle style
Title ofpresentationClick to edit subtitle style
THANK YOU !!
29
Contact