Cheri Perception

Cheri Perception

Hubert Pan Cathy Zhang Bryan Cua Tilson Chung

Product Overview Operation Simulation Statistics Prototype Future Development

Product Overview

VBSS Voice over IP Bandwidth Saving System Product as Dynamic Operator Paper Cup Analogy

Reduce operation costs Minimize network resource usage Pioneer dual voice stream compression

EXISTING TECHNOLOGY Single stream compression VBSS PRODUCT Dual stream compression Designed on top of single stream compression

Operation

John Alex Jill Alice

Jill John Big Pipe (Internet) Alex Alice

Jill John Big Pipe (Internet) Alex Alice

Voiced Unvoiced Silent

Simulation

MATLAB, C Pulse Code Modulation Voice recorded Webcam Microphone

Formant Estimation Fundamental Linear Frequency Estimation and nonlinear filters

BEFORE AFTER

Prototype

A small network support up to 6 devices 4 Grandstream VoIP phones PC FPGA board (Xilinx XUP-V2P)

Hardware (Xilinx XUP-V2P): 32-bit MicroBlaze processor Low-Frequency On-Chip Peripheral Bus (OPB) Fast Simplex Link Bus (FSL) Fast Fourier Transform G711 μ-law codec

Statistics

Frames Packet

Packet (pkt) Size 218 bytes/pkt 1744 bits/pkt Data Packets arrive every 20 ms (λi 1 for each phone) 4 pkt λT i 20 ms 200 pkt/s i 1 4 348800 bits/s

Packet Processing Time Division 20 ms Processing Time Line for One Phone μT 5 ms 2 (0.432 0.214 0.654 0.04) ms for 2 pkt 3.84 ms / packet 260 .4 packet / s C Packet Service Rate Average Packet Length (260.4 packets/s) (1744 bits/packet) 0.454 Mbps

10/100 Mbps switch accommodates the system capacity System Utilization 0.454 Mbps 10 Mbps 4.54% Traffic Intensity ρ λT μT 76.8 %

Speech Characteristic Type of Frame % of Frames Combined 60% Overall Saving 30% Voiced 90% Unvoiced 10% Module-added Delay Module Time Autocorrelation 0.432ms PEF 0.654 ms Send Packet Function 0.0425ms MLP 0.214ms

Future Development

Simulation vs Prototype No packets Clear-cut frames Calculation Precision Prototype Environment too different from reality Single network port board Lone product Low interference

Robustness Problems Thresholds Background noise Noise between frames

Processing power Network Interfaces

Professors Lakshman One Steve Whitmore Lesley Shannon