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Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications. CUBAN Scenario. Copied from: “In-depth description of the Research Proposal Co-Optimized Ubiquitous Broadband Access Networks” (CUBAN). Key Points. Cross-layer optimization Uplink and downlink.
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Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
CUBAN Scenario Copied from: “In-depth description of the Research Proposal Co-Optimized Ubiquitous Broadband Access Networks” (CUBAN) Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Key Points • Cross-layer optimization • Uplink and downlink Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
packets per time slot versus Cross-Layer Optimization Copied from: “Cross-Layer Design for Wireless Networks”, S. Shakkottai and T. Rappaport Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization • Assumption: Both the transmitter and the receiver operate on batteries • Goal: Find the best modulation strategy to minimize the total energy consumption required to send a given number of bits Based on: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai “Energy-constrained Modulation Optimization for Coded Systems”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization • Analysis for: • MQAM, MFSK • AWGN and Rayleigh fading channels • Coded / uncoded case Based on: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai “Energy-constrained Modulation Optimization for Coded Systems”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization • In short range applications, the circuit energy consumption is non negligible compared with the transmission energy Based on: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai “Energy-constrained Modulation Optimization for Coded Systems”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization Copied from: “Energy-constrained Modulation Optimization”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization • bits have to be transmitted in a deadline • The transceiver spends a time to transmit those bits • Trade off: the transmission energy decreases with , but the circuit energy consumption increases with Based on: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai “Energy-constrained Modulation Optimization for Coded Systems”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization • Example: Uncoded MQAM for AWGN channels Copied from: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization Copied from: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy-constrained Modulation Optimization Copied from: “Modulation Optimization under Energy Constraints”, S. Cui, A. Goldsmith and A. Bahai Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Use transmitter – receiver pair n when Adaptive Transmission Schemes Copied from: “Adaptive Coding and Modulation: A Key to Bandwidth-Efficient Multimedia Communications in Future Wireless Systems”, K. Hole and G. Øien Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Adaptive Transmission Schemes The channel model specifies a pdf for the amplitude of Copied from: “Adaptive Coding and Modulation: A Key to Bandwidth-Efficient Multimedia Communications in Future Wireless Systems”, K. Hole and G. Øien Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint • Goal:Adapt radio settings (e.g. modulation, error code, …) in response to changes in the wireless channel in order to minimize the energy consumption under an average throughput constraint Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint • System model: Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint • Assumptions: • The channel (Rayleigh fading) varies slowly enough to be estimated efficiently • Infinite number of samples Only knowledge of the channel statistics is required, instead of that of the exact future behaviour Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint • Problem:Find the values of the thresholds • Assumption: The incremental power for adding one extra bit is monotonically increasing Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Energy Optimal Scheduling under Average Throughput Constraint Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Results Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Results Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Results Based on: “Energy Efficient Wireless Scheduling: Adaptive Loading in Time”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Remarks – Ideas – Discussion • Conclusions from p2: • Minimize energy consumption instead of maximizing spectral efficiency when determining the thresholds • The analysis has been done for situations where the electronics power is negligible compared to the transmission power Based on: “Energy Optimal Scheduling under Average Throughput Constraint”, C. Schurgers and M. Srivastava Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Research Objective 1 Design an adaptive transmission scheme (i.e. determine the thresholds, ,… ) for short range wireless channels in order to minimize energy consumption under an average throughput constraint Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Research Objective 1 • Remarks: • The electronics (circuit) power is not considered negligible when compared to the transmit power. A model comparable to the one in p1 will be used • In a first stage, MQAM modulation (no coding) and Rayleigh fading • The throughput constraint should be set by the application layer Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Research Objective 1 • It would be interesting to find out how far the transceiver designed using the above scheme is from the from the actual channel capacity Based on: “Adaptive Coding and Modulation: A Key to Bandwidth-Efficient Multimedia Communications in Future Wireless Systems”, K. Hole and G. Øien Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Other Ideas • Nakagami-m channels • See what happens with p1 • Research objective 1 • OFDM based schemes, with adaptive transmission on subchannels • Coding: Trellis codes / Turbo codes Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications
Other Ideas • Antenna diversity – SC / MRC • Try to find more accurate / complete models for the electronics power consumption, try to find the best possible transceiver structure in terms of power consumption • Network and data linklayers joint optimization Bandwidth-Efficient, Energy-Constrained Short Range Wireless Communications