ENERGY EFFICIENCY IN GPS

SEMINAR TOPIC

ENERFY EFFICIENCY IN GPS

International Institute of Information Technology, Pune – 411057

GUIDE:Prof.Ramkrushna sir

PRESENTED BY:Aditi Gadgul

TE(Compter Enng)

• Battery consumption consideration• Without GPS turned on a cellphone battery level

drops to 94% in an hour• With GPS turned on a cellphone battery level drops

to 56% in an hour

With GPS turned on

With GPS turned off

INTRODUCTION

MOTIVATION

ABSTRACT

Smart phones are equipped with powerful sensor sets Wifi GPS Acceleration orientation

Coverage area of GPSAccuracy of GPS

LITERATURE SURVEY

TRADITIONAL GPS SYSTEM

Continues GPS sensingHence more energy

consumption

Sample points

So how to reduce this??

PROPOSED GPS SYSTEM

APPROACH 1

Use of pre-existing sensorsAcceleration Orientation

An alternative to GPSWIFI based tracking system

Introduction of new serviceA prototype which will do switching between

alternative tracking technique

HOW IT IS DIFFERENT??

Limited availability of GPS verses Multiple Location sensing methods

Unnecessary GPS sampling verses Adaptive Listening

Assistance from other Sensors

CHALLENGES AND OPPORTUNITIES

SYSTEM ARCHITECHTURE

Accelerometer

OrientationSensor

GPS WIFI

Location Samples

Reconstructed Track

Gaussian Processregression

SMARTPHONE

SERVER

1.Data Collection and MethodologyThe prototype continuously collects data from sensors at default

rate of the system

PERFORMANCE EVALUATION

T= 1s 3s 5s 7s

Key turning points

4misses

1 0 0

Theta= 45 60 75 90

Key turning points

0misses

1 3 4

2.Accuracy

Recorded locations

Predicted locations

Averageerror

AlternativeTrace

38 samples 24 predictions 3.12 m

GPSTrace

568 samples 0 0

Average Error

3. Energy Efficiency

Altern

ativ

e

trad

ition

al

Altern

ativ

e

trad

ition

al0

200

400

600

800

1000

1200

Comparison of energy ef-ficiency

Time of GPS

sensorBeing active

Number of GPS location sampling

GPR (Gaussian Process Regression) :

ALGORITHMS USED

NEEDS ONLY 7% GPS SAMPLES OF TRADITIONAL APPROACH

SAVES NEARLY 90% GPS ACTIVATED TIME

RECONSTRUCTS USER’S TRAJECTORY WITH HIGH ACCURACY AND BETTER COVERAGE

Hence…..

APPROACH 2

REASONS

An MLSA requires timely and accurate location information, so it favors keeping GPS receivers in the ON mode continuously.

An MLSA generates a substantial amount of continuous data, including the trajectory of the moving object (i.e., the location information etc).

For reducing the energy required for MLSA GPS tracking

1. EBT(Event Based GPS Tracking)which uses:

Static duty-cycle(SDC) Dynamic duty-cycle(DDC)

ALGORITHMS USED

For reducing the energy required for data communication:

2. IFC(Inter-Fame Coding)which uses:

Byte-level compression (Decompression) Spatial-temporal compression (Lossy)

FLOWCHART

Event Based GPSTracking System

The location of GPS trackingdeteriorates in two situations:

1) The GPS receiver has been in the OFF mode for longer period

2) There has been a significant change in the movement pattern of

the object.

Approach 1

Approach 2

Modified Algorithm

PROPOSED ALGORITHM

Data Decompression(Using IFC)

ADVANTAGES

Easy and simpleFast than traditional LBSReduction in server stressMinimized energy consumption

CONCLUSION

Hence the energy consumption of the traditional GPS system is reduced with the help of new prototype which switches between traditional and naive location tracking system

Overcome limitations in existing system

i. Other indoor technologiesii. Energy consumption of accelerometer and

orientation sensoriii. Multiple mobility patterns

Study of algorithms to reduce server stress

FUTURE WORK

THANK YOU

QUESTIONS??