Wireless IC Node with Compression Heuristics (W.I.N.C.H.) Final Design Review Steve Jocke, Kyle Ringgenberg, Stuart

System Data Flow Overview

PIC Overview PIC16C5X.UVa Stats –4 Interrupts / 3 Input ports / 5 output ports / 32 Instruction –Operating voltage of 300mV –Input clock frequency of 800KHz Clock divided down to 200Khz for PIC internal cycles Approximately 200 Instructions (I-cycles) between ADC Samples System overhead requires approximately 30 I-cycles –Required to track input values for gain adjustment to ADC –Leaves ~ 170 I-Cycles free for compression, second core not required

Run Length Encoding Replace Repetition with Occurrence Counts –Lossless: Only Identical Values Replaced  [3]0 1 3 [2]5 6 –Lossey: Values with a Tolerance Replaced  [4]0 3 [3]5 –Variable Parameters Codeword Size – Max Repetition Length Block Size – Insert Repetition Code Every Block –CODE x BLOCK = WORD Tolerance – “Stray-ability”

Run Length Encoding

All Variants Require Additional Repetition Blocks Compression Ratio –Lossless Poor – Worst Case is Worse than Raw –Lossey Excellent – Saturates to Best Compression Ratio Executable in O(n) –36 Clock Cycles –7 Registers

Delta Encoding Replace Values with Changes in Values –Lossless Global: Greatest Δ Dictates Remapping  8x 3-bit “Words”  24 bits  7x 2-bit “Words”  14 bits –Lossless Local: Each Δ Treated Independently  4x 1-bit, 3x 2-bit “Word”  10 bits Additional Data for “Word” Lengths –Lossey Global: Mean Δ Dictates Remapping  8x 1-bit  8 bits Decoded as:

Delta Encoding Tightly Clustered Long Tail

Delta Encoding Longer Tail, but no Bit Change!

Delta Encoding

All Variants Require Additional Sign Bit Compression Ratio –Lossless Mediocre – Significant Degree of Overhead Bits –Lossey Mediocre – Fidelity is Data Dependent Execution in O(n) –37 Clock Cycles –6 Registers

Compression Conclusions 10x

Mixer Design Vdd 1.2V Active Power: –50GHz LO –100Mbs –9.23mW Active Power: –1.5 GHz LO –100Mbps –716.67uW

15GHz Local Oscillator Startup Delay: – ps Startup Power: –4.471mW Run Power: –6.050mW Off Power: – μW

LO – 3 Stage Inverter and Buffer 1.5 GHz Startup Time: –2.3ns Startup Energy: –6.92pJ Startup Power: –3mW Avg Power: –3.502mW Off Power: –1.804μW

High Speed Power Examples VCO Core: 1mW 1 51GHz Mixer:97mW GHz Gilbert Cell Amplifier 54mW 3 60GHz 1.52nJ/bit (100Mbps) 3.04μJ/2Kbit (100Mbps) 1. Tiebout, M.; Wohlmuth, H.-D.; Simburger, W., "A 1V 51GHz fully-integrated VCO in 0.12/spl mu/m CMOS," Solid-State Circuits Conference, Digest of Technical Papers. ISSCC IEEE International, vol.2, no., pp , Lin, C.-S.; Wu, P.-S.; Chang, H.-Y.; Wang, H., "A 9-50-GHz Gilbert-cell down-conversion mixer in 0.13-/spl mu/m CMOS technology," Microwave and Wireless Components Letters, IEEE, vol.16, no.5, pp , May Doan, C.H.; Emami, S.; Niknejad, A.M.; Brodersen, R.W., "Millimeter-wave CMOS design," Solid-State Circuits, IEEE Journal of, vol.40, no.1, pp , Jan. 2005

Power Consumption of PIC (No Compression) Time μ sec

Power Consumption of PIC (cont’d) Measurements –Ultrasim Simulator used to measure current Set in MS (Mixed Signal / Analog Mode) PIC Power Summary –Without compression 1.) NOP Inst Power 318.1nW (Averaged over 4 NOP’s) 2.) AVG Inst Power nW (All runtime - 2mS) –With compression 3.) AVG Inst Power nW (Over Compression Algorithm) 4.) AVG Inst Power nW (all runtime – 2mS) –Final Stats Overall Inst Power 323.7nW Delta Power Modes 1.51nW Conclusion –Power Consumption is about the same no matter what operation Using free I-cycles recovers wasted power Also could throttle back clock frequency

Energy Totals for Communication Channel 15GHz –On Energy (Mixer + LO): 152.8pJ/bit 305.6nJ/2Kbit –Off Power (LO): 69.39μW 1.5GHz –On Energy (Mixer + LO): 35.06pJ/bit 70.1nJ/2Kbit –Off Power (LO): 1.804μW Bluetooth 4 –On Energy: 297.5pJ/bit – 165nJ/bit –Sleep Power 825μW –Idle Power 8.25mW 4. Roving Networks RN-41 V1.5 11/14/07 Documentation

Summary Base Case (Bluetooth) Compression (10/1) –.324nJ/Sample (PIC) –2.38nJ/byte (Bluetooth) –827nJ/Sample No Compression –.324nJ/Sample (PIC) –2.38nJ/byte (Bluetooth) –842.4nJ/Sample Wireless Compression (10/1) –.324nJ/Sample (PIC) –1.224nJ/byte (LO) –74.5nJ/Sample No Compression –.324nJ/Sample (PIC) –1.224nJ/byte (LO) –68.8μJ/Sample