UWB Tracking Software Development

Abstract

An Ultra-Wideband (UWB) two-cluster Angle of Arrival (AOA) tracking prototype system is currently being developed and tested at NASA Johnson Space Center for space exploration applications. This talk discusses the software development efforts for this UWB two-cluster AOA tracking system. The role the software plays in this system is to take waveform data from two UWB radio receivers as an input, feed this input into an AOA tracking algorithm, and generate the target position as an output. The architecture of the software (Input/Output Interface and Algorithm Core) will be introduced in this talk. The development of this software has three phases. In Phase I, the software is mostly Matlab driven and calls C++ socket functions to provide the communication links to the radios. This is beneficial in the early stage when it is necessary to frequently test changes in the algorithm. Phase II of the development is to have the software mostly C++ driven and call a Matlab function for the AOA tracking algorithm. This is beneficial in order to send the tracking results to other systems and also to improve the tracking update rate of the system. The third phase is part of future work and is to have the software completely C++ driven with a graphics user interface. This software design enables the fine resolution tracking of the UWB two-cluster AOA tracking system.

https://ntrs.nasa.gov/search.jsp?R=20060013650 2020-06-07T01:00:52+00:00Z

1

UW

B T

rack

ing

Softw

are

Dev

elop

men

t

Julia

Gro

ssD

icke

y Ar

ndt,

Phon

g N

go, C

hau

Phan

, Joh

n D

usl,

Jian

jun

(Dav

id) N

i

UW

B Sy

stem

s Gro

up /

EV4

Avi

onic

Sys

tem

s Div

ision

/ EV

NA

SA J

ohns

on S

pace

Cen

ter

2

Intr

oduc

tion

An U

ltra-

Wid

eban

d (U

WB

) tw

o-cl

uste

r Ang

le o

f •

Arriv

al (A

OA)

trac

king

pro

toty

pe s

yste

m is

cu

rren

tly b

eing

dev

elop

ed a

nd te

sted

at N

ASA

Jo

hnso

n Sp

ace

Cen

ter f

or s

pace

exp

lora

tion

appl

icat

ions

.

This

talk

dis

cuss

es th

e so

ftwar

e de

velo

pmen

t •

effo

rts

for t

his

UW

B tw

o-cl

uste

r AO

A tr

acki

ng

syst

em.

3

Intr

oduc

tion

UW

B is

an

emer

ging

com

mun

icat

ions

tech

nolo

gy

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like

trad

ition

al C

ontin

uous

Wav

e (C

W) n

arro

w

band

sys

tem

s. T

he te

chno

logy

was

app

rove

d by

FC

C in

Feb

ruar

y 20

02.

Feat

ures

: Hig

h da

ta ra

te, f

ine

time

reso

lutio

n an

d lo

w

•po

wer

spe

ctra

l den

sity

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UW

B s

yste

m is

use

d fo

r com

mun

icat

ions

with

add

ed

•pa

ssiv

e tr

acki

ng

4

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rvie

w

Use

ful f

or tr

acki

ng ro

vers

and

ast

rona

uts

for e

arly

•

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r/Mar

s ex

plor

atio

n m

issi

ons

whe

n na

viga

tion

syst

ems

(suc

h as

GPS

) are

not

ava

ilabl

e

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vehi

cle

as te

st-b

ed fo

r Lun

ar/M

ars

rove

r •

prot

otyp

e

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llent

trac

king

per

form

ance

with

less

than

1%

err

or

•at

rang

es u

p to

200

0’

5

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ize

com

mer

cial

ly a

vaila

ble

UW

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dios

and

•

cust

omiz

e fo

r our

spe

cific

app

licat

ions

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ios

are

deve

lopm

ent k

its a

nd a

re n

ot p

lug

and

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ay

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ios

esse

ntia

lly tr

ansm

it an

d re

ceiv

e an

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•si

gnal

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se th

e ra

dios

:•

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elop

the

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orith

m–

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elop

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are

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evel

op th

e H

ardw

are

–

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rvie

w

6

Func

tiona

lity

of th

e U

WB

Tra

ckin

g So

ftwar

e

-25

0-2

00

-150

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0-5

00

50

10

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20

02

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0

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0

1000

1500

2000

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Rx

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enna

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t: W

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dat

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calc

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h w

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softw

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wav

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tput

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tC

ore

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put

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efor

m d

ata

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tion

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05

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00

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00

25

00

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0

10

00

15

00

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00

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00

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t: W

avef

orm

dat

a fro

m R

xs

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lgor

ithm

take

s da

ta fr

om R

xs a

nd

calc

ulat

es p

ositi

on o

f Tx

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put :

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ition

of T

x

9

The

arch

itect

ure

of th

e so

ftwar

e in

clud

es th

e •

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t/Out

put I

nter

face

and

the

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orith

m C

ore.

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t: • W

avef

orm

dat

a co

ntai

ning

tim

ing

•in

form

atio

n re

ceiv

ed fr

om fo

ur a

nten

nas

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e:• A

OA

trac

king

alg

orith

m•

• E

xtra

cts

timin

g in

form

atio

n fr

om

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efor

m d

ata

and

calc

ulat

es p

ositi

on o

f tr

ansm

itter

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put:

• Con

vert

s th

e po

sitio

n da

ta in

to G

PS

•co

ordi

nate

sy

stem

to tr

ack

rove

r

• Plo

ts a

nd d

ispl

ays

the

posi

tion

data

to

show

ac

cura

cy o

f the

sys

tem

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hite

ctur

e of

U

WB

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ckin

g So

ftwar

e

10

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t:

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llel M

ulti-

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et

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ram

min

g

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et

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acke

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ket 2

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ket 2

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11

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efor

m d

ata

is d

ivid

ed in

to 2

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gmen

ts a

t rad

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are

has

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ent f

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ket

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er 1

and

then

take

s on

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t ove

r th

e ot

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t fro

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er 2

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alte

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is re

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a co

mpe

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orm

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ssem

bled

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radi

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and

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the

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me

inst

ant i

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accu

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ram

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WB

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ckin

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ent

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-250

-200

-150

-100

-50

05

010

015

020

025

00

500

1000

1500

2000

2500

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rt

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Arr

ay

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ket

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ket

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lab:

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lgor

ithm

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ket 2

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ket 2

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eive

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ay

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are

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par

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n w

hich

trea

ts th

e C

++ p

ortio

n as

if it

wer

e ju

st a

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lab

func

tion

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lab

uses

C++

to p

rovi

de th

e co

mm

unic

atio

n •

links

to th

e ra

dios

via

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cket

s

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efic

ial i

n th

e ea

rly s

tage

whe

n it

is n

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sary

to

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ntly

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cha

nges

in th

e al

gorit

hm, b

ette

r to

use

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lab

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wba

cks

are

the

effic

ienc

y of

ope

ning

and

•

clos

ing

the

sock

ets

on e

ach

loop

in M

atla

b –

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, pl

ottin

g in

Mat

lab

take

s up

tim

e

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e I o

f U

WB

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ckin

g So

ftwar

e D

evel

opm

ent

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e II

of

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rack

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ket 2

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ket 2

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-100

-500

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015

020

025

00

500

1000

1500

2000

2500

Sta

rt

End

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ay

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t Pos

ition

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eive

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a

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ayTx

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d V

ehic

le it

s P

ositi

on

Mat

lab: