1. 1 WP3.3: Steerable antenna technologies: Signal processing aspects Participants: UoY (18MM); POLITO (19MM); EUCON (6MM) Tim Tozer & Yuriy Zakharov

2. 2 Workpackage Tasks Beamforming for HAPs (UoY) In particular, for communications with high-speed trains Beamforming for ground terminals (POLITO) In particular, installed on high-speed trains Implementation aspects (EUCON) In DSP software

3. 3 Explore Terminal Constraints  Geometry  Size / Mass  Speed (Pointing, Doppler)  Etc. Explore System Requirements  Link Budgets  Tracking / Availability  Polarisation  Geometry  Etc. Philosophy for both WP 3.2 & 3.3  Identify promising solutions  Explore enhancements  Assessment of most promising solutions in terms of requirements  Develop enhancements Develop selected promising concepts Explore Prior Art  Antennas  Associated Signal Processing Agree Requirements Spec time M0 M4 M12 End Mar 04 Identify Signal Processing Issues. Develop interesting SP aspects?

4. 4 WP3.3 Input from other WPs RF aspects of steerable antennas (from WP3.2) Antenna array architecture Variation / tolerances in antenna array geometry; calibration aspects (real-time calibration; reliability of antenna array elements Variation / tolerances in delays, phase shifts, element gains/weights, etc. Communication signal structure (from WP2.1) Propagation (from WP2.2) Fading correlation of received signals over the antenna aperture and time Multipath structure of received signals (number of multipath components, angle and delay profiles) Platform stability (from test trials??)

5. 5 WP3.3 Milestones & Deliverables Internal Milestones + Documents, Month 5: a) Possible approaches for RF, EM and Mechatronic Aspects of Train & HAP antennas. b) Possible approaches for Signal Processing Aspects of Train & HAP antennas. Month 12: Possible antenna topologies for ground terminals and aerial platforms identified Month 24: Beamforming algorithms and implementation aspects for ground terminals and aerial platforms specified Month 34: Detailed design of adaptive beamforming algorithms for ground terminal and aerial platform antennas Deliverables D17: Report on adaptive beamforming algorithms for advanced antenna types for aerial platform and ground terminals (M27). D28: Report detailing the implementation aspects of signal processing for aerial platform and ground terminal beamformers (M36).

6. 6 Antenna geometry options Overlapping subarrays Simplify the feed network, RF part and signal processing Vertical antennas Non-traditional foot-print Random element positions Dispersed array structure Errors in element positions

7. 7 Methodology Asymptotic theoretical analysis Computer simulation of proposed techniques Extrapolation of concepts from “Underwater acoustic antenna arrays” Valuable pedigree from digital beamforming for large acoustic arrays

8. 8 Research topics Adaptive algorithms: Simple implementation (DSP software, FPGA & ASIC hardware platforms) Low power consumption Algorithms for matrix computations Solution of linear systems of equations Matrix inversion Eigenvalue decomposition Effect of errors Look direction and steering vector errors Element failure and element position errors Weight errors Antenna array calibration

9. 9 Dichotomous Coordinate Descent (DCD) algorithm Real-time solutions to large systems of linear equations Fixed-point oriented algorithm (software implementation on a DSP platform) Does not involve multiplications or divisions (hardware implementation on FPGA & ASIC) Fast convergence Current applications Echo cancellation Equalisation Multiuser detection Tomography Possible applications Adaptive algorithms Matrix inversion Eigenvalue decomposition Publications: Zakharov Y. V. and Tozer T. C. “Data processing, particularly in communication systems”, Patent Application, GB0208329.3, WO03088076, Published Oct. 2003. Zakharov Y. V. and Tozer T. C. “Equation solving”, Patent Application, GB0324191.6, US10/685983, Filed Oct. 2003. Zakharov Y. V. and Tozer T. C. “Box-constrained multiuser detection based on multiplication- free coordinate descent optimisation”, ICASSP’2004, Submitted.

10. 10 Reminder: WP 3.2 - Steerable antenna technologies: EM, RF and mechatronics aspects Start date: M0 Participants : UOY (16MM) CSEM (31MM) SkyLINC (1MM) CRL (5MM?) Objectives: To investigate the antenna electromagnetic, RF and mechanical aspects for the mobile mm-wave broadband delivery and put forward solutions for the critical components. Outline Description 1: Aperture Antennas To determine impact of statistical variability of real antenna parameters on performance characteristics of the system as a whole. Mathematical tools based on real antenna specifications & measurements developed to calculate system performance & variation 2: Smart Antennas Study smart antenna configurations to determine suitability for moving platforms. Consider smart antenna types, technologies and topologies. a)Fast Trainsb)HAP antenna array. Feasibility of implementing the required RF hardware will be investigated. Solutions will also relate to the signal processing (beamforming algorithms) activity WP3.3 3: mm-wave RF front end. Deliverables: D24 Steerable antenna architectures and critical RF circuits performance. (M35) Milestones: M6. HAP payload antenna statistical variance. Concepts for “train” antennas including mechatronics. M12. RF circuit constraints. Design experiment for validation of concepts. M18. Model mm-wave active element performance for steerable antenna implementation. M30. Test evaluation and specification of preferred solution for steerable antenna

11. 11 Reminder WP 3.3 - Steerable antenna technology: Signal processing aspects Start date: M0 Participants : UOY (18MM) POLITO (19MM) EUCON (6MM) Objectives: Investigation of advanced adaptive beamforming technologies not previously considered to determine applicability to aerial platform applications and their expected performance within HAP communications scenarios. To design a vehicular steerable antenna such as might be deployed on a train. To enable communication with an aerial platform anywhere within the coverage area. Outline Description 1: Beamforming Antennas Design to establish & improve communication link between HAP and ground terminals. Design of an adaptive beamformer on-board of the platform, exploiting fast adaptability of an electronically steered beam pattern. 2: Beamforming algorithms for ground terminal antennas Implementing adaptive beamforming solution at the CPEs and on vehicles, to continuously track HAP trajectory.

12. 12 Reminder WP 3.3 /contd 3: Implementation aspects of beamforming algorithms Will define the mm-wave equipment specification and characteristics required for smart antenna implementation. The specification will include both a transmit and receive chain configurations, noise performance, output power, linearity, filtering requirements, etc. The work will also define the interface to the software radio IF. 4: Beamforming Algorithms Implementation aspects of signal processing algorithms. Technological issues such as quantisation, fixed/floating point algebra, design optimisation in terms of power and computational efficiency. Aimed at implementation of selected algorithms on DSP. The performance will be assessed by simulating real working conditions. Deliverables D17: Adaptive beamforming algorithms for advanced antenna types for aerial platform and ground terminals (M27). D28: Implementation aspects of signal processing for beamformers (M36). Milestones and expected results M12: Possible antenna topologies for ground terminals and aerial platforms M24: Beamforming algorithms & implementation aspects for those terminals M34: Detailed design of adaptive beamforming algorithms

13. 13 Document Properties