COMPUTER ARCHITECTURE & SOFTWARE-DEFINED RADIO NEBU JOHN - PowerPoint PPT Presentation

COMPUTER ARCHITECTURE & SOFTWARE-DEFINED RADIO NEBU JOHN MATHAI DIRECTOR, ENGINEERING AND ARCHITECTURE

INTRODUCTION Higher Communications Performance System Substrates Architects Increased Hardware Algorithm Architects Complexity More Performance

COMPUTER ARCHITECTURE  SDR New standards, New uses Higher SDR performance Novel Computer Architectures

TRENDS • Communications standards complexity Algorithmic diversity • • Large parameter spaces Cross-stack communication • • Processing power • Flexibility • Better Language/Compilers • Express complex ideas correctly • Efficient mapping

TRENDS • IOT: Boldly going where no radio has gone before Power consumption • • Flexibility Malleability • • High Performance Computing Scaling: both directions • Edge Edge Big Big • Power efficiency Computing Computing Compute Compute Architectural diversity • HPC

OVERVIEW • Quick look at history Computer architecture  SDR •

HISTORY Computation • C.E. Shannon Digital Hardware Engineering • • Information Theory A. N. Kolmogorov • Control Communications • Algorithmic Information Theory N. Wiener, W.R. Ashby, … • • systems { convey, store, process } information for control

HOW DID WE GET HERE? Analog to • Constraints and Requirements Digital • New standards and interfaces • IOT: malleability, performance, power economy Hard Digital • Cognitive radio: same to Soft Digital Advanced sensing: high-performance • Canonical to exotic HPC

COMPUTATION • Map: math -> physical substrate Analog • • Variables analogous to physical quantities Transistors in linear region • • Digital Variables are analogous to abstractions • • Transistors in discrete on/off states

1. (A2D) ANALOG COMPLEXITY • Design Complexity Verification Complexity • • Simulation • Mismatch: ODE and digital computers • Simplifications Validation Complexity • • Smaller-scale vital systems

1. (A2D) DIGITAL SOLUTIONS • Arbitrary precision, dynamic range H(z) => hardware implementation • • Control flow Scalability • • Tractable Verification + Validation Discrete-time simulation directly maps to digital computers • • Integration with software stack

1. (A2D) REPERCUSSIONS complexity Analog Analog Hard digital Hard digital Soft digital Soft digital • Verification Complexity State space explosion • • Adequate stimulation requires lots of time Simulation: orders of magnitude slower than real time • • How to practically ensure you’ve covered all cases?

2. (H2S) MAKE IT SOFTWARE’S PROBLEM Digital Front End Digital Front End Control Knobs Control Control Processor Processor • Add knobs to the digital front end When it becomes impractical to control the knobs … • • … develop schemes to control them via a processor

2. (H2S) MAKE IT SOFTWARE’S PROBLEM • Solves the Design + Verification problem: Processors are well-known systems • • Adding features: easy Achieving performance: hard • Innovative architectures to address this •

3. ARCHITECTURES: BASIC Instruction Instruction RAM RAM Data Input Data Input Data Output Data Output … RAM RAM RAM RAM Functional Units

3. ARCHITECTURES: DSP Instruction Instruction RAM RAM Data Input Data Input Data Output Data Output … RAM RAM RAM RAM More Functional Units

3. ARCHITECTURES: SIMD Instruction Instruction RAM RAM Data Input Data Input Data Output Data Output … RAM RAM RAM RAM Parallel Functional Units

3. ARCHITECTURES: MIMD Instruction Instruction RAM RAM Data Input Data Input Data Output Data Output … RAM RAM RAM RAM Parallel Independent Functional Units

3. ARCHITECTURES: VLIW Instruction Instruction RAM RAM Data Input Data Input Data Output Data Output RAM RAM RAM RAM

3. ARCHITECTURES: GRID

3. HETEROGENEOUS SYSTEMS • Demanding Hardware architecture, design and verification • • Software engineering Worthwhile • • Ideal performance characteristics