Department of Electronics and Communications Engineering Activities in electromagnetic track Progress report, year 2015 Presented by: Dmitri Moltchanov Tampere University of Technology

Department of Electronics and Communications Engineering  Local TUT team  Dr. D. Moltchanov  PhD student V. Petrov  MSc. student M. Komar  Current collaborators  CPU: Dr. P. Kustarev, ITMO, Russia  CPU: Dr. R. Shaloo, NYU  B2B: Dr. J. Lehtomaki, Oulu, Finland  THz propagation: Dr. G. Molis, Teravil, Lithuania Personnel

Department of Electronics and Communications Engineering  Dense THz random deployments  Interference, SINR, connectivity, spectral efficiency  Methods: stochastic geometry  Wireless THz CPU design  Feasibility, traffic modeling, design  Methods: measurements, simulations  B2B communications  Cooling/transmission pipes  Methods: THz-TDS measurements, COMSOL Active topics

Department of Electronics and Communications Engineering  Questions of interest  Interference, SIR, optimal communications distance  What is the difference?  Received signal strength  Noise at the receiver  What has been done this year:  Interference: VTC’15, opt. distance: Globecom’15  THz booth d scenario for ICC’16 1. Dense THz networks

Department of Electronics and Communications Engineering  Board-to-board communications in THz  One of the killer app in IEEE d  Principle: waveguide with coolant inside  What has been done this year:  ACM Nanocomm’15 + journal under preparation 2. Joint cooling/transmission system

Department of Electronics and Communications Engineering  Wireless cores-LLC interface in CPUs  Communications subsystem: bottleneck  How to efficiently connect e.g. 50 cores to LLC?  Existing architecture  Step-by-step: terahertz-traffic-feasibility-design 3. Wireless CPU design

Department of Electronics and Communications Engineering  Methodology: measurements, extrapolation  8-cores Intel Core i7 Haswell-E 5980X, 20Mb LLC  Intel PCM (counters available since SandyBridge) 3. Feasibility of THz

Department of Electronics and Communications Engineering  Proposed 3D-stacked design  Current questions:  Propagation inside compartment and materials  MAC design for intra-CPU traffic 3. Wireless CPU design

Department of Electronics and Communications Engineering  Propagation and materials  Ray-launcher is being developed  Measurement by Teravil  Traffic nature and MAC  CPU modeling (gem5, ITMO)  Measurements using Intel PCM  What has been done this year  Two journal papers + conference paper 3. Current research focus

Department of Electronics and Communications Engineering  Traffc at L2-L3  Stochastic even for a single core and simple app!  Far from Poisson assumption  Has clearly distinguishable batch behavior 3. Example of L2-L3 traffic Reading Encryption