telemetry, tracking and control

8/16/2019 Telemetry, Tracking and Control

1/20

TELEMETRY, TRACKING &CONTROL


2/20

Project Group Members

Nadeem Hussa! Asm "a#eed


3/20

Te$emetr%, Trac!' & Co

A commu!cato! s%stem ($$ be de)e$opede$eme!ts to detect a!d correct c#a!'es+

T#e rado $! ($$ be eam!ed *or prop

$osses a!d !umbers t#at descrbes t#e !ose t#at ca! a-ect a s'!a$ dur!' tra!sus!' .NR+

T#e s'!a$s ($$ be modu$ated b% t#e r

carrer (a)es+


4/20

Commu!cato! .%stem

.ame commu!cato!s%stem *or te$emetr%& 'rou!d stato!+

/-ere!ces !#ard(are


5/20

AX25 Link Protocol

T#s protoco$ s used #ere to detect a!d corre

Frame Format:

"#e! a co!!ecto! s estab$s#ed t#e data *rase!t re)erse a!d *or(ard bet(ee! t#e stato!


6/20

C%c$c Redu!da!c% C#ec 0CR

.!'$e bt errors

T(o so$ated s!'$e bterrors, +e+ t(o 23s ! E01(t# 4eroes bet(ee!

A$$ !sta!ces o* E01 (t#a! odd !umber o* o!es

5urst errors o* up to 26bts, +e+ E01 co!ta!s 26co!secut)e o!e3s

T#e 7C. 8e$d co!269bt CRC c#ect#e data ca$cu$ated

T#s c#ecsumca$cu$ated *rom bIN7O 8e$d as (e$!o! pa%9$oad !o


7/20

Retransmission andAcknowledgement

T#e A;


8/20

MX909 Modem

T#e M;>?> modem a!d ts dr)er so*t(are taes t#e Aa!d breas t#em up !to sma$$er pacets t#at are betttra!smsso! o)er a possb$e u!re$ab$e (re$ess $!+

Etra o)er#ead b%tes are used *or 7or(ard Error Corrsc#eme, as (e$$ as c#ecsumm!' a!d se!

s%!c#ro!4ato!+ Modem data s ! t#e *orm o* GM.K modu$ato!+


9/20

or(ar rror orrec o!07EC1

7EC ca! o!$% detect a!d correct s!'$e bt error as ! abeam $e


10/20

7rame Head

T#e 7rame Head s%!c#ro!4es t#e data b@( se!der a!d res ac#e)ed b% se!d!' t(o b%tes o* bt9s%!c#ro!4ato!t(o b%tes o* *rame9s%!c#ro!4ato!+

T#e s%!c#ro!4ato! b%tes are used *or t#e modem crcut#e s'!a$ a!d $oc o!to t+ T#e t(o co!tro$ b%tes are use

t#e tota$ !umber o* b%tes co!ta!ed ! t#e /ata 5$ocs+ Last b%te o* 7rame Head s a! 7EC b%te (t# bts *or

co!tro$ b%tes+


11/20

/ata 5$ocs

T#e data to be se!t s sp$t up ! to b$ocs o* 2B b T#ese b$ocs are t#e! tra!s*ormed !to /ata add!' < b%te CRC c#ecsum ca$cu$ated *rom t#b%tes+ T#e! bts o* 7EC are added *or eac# b%tt#e ca$cu$ated CRC c#ecsum+ T#s br!'s t#e

5$oc up to ? b%tes (#e! se!d!' 2B b%tes o* da


12/20

Link Budget

A!a$%4e t#e amou!t o* errors !ducedata stream b% t#e commu!cato! c#t#e rece)er e!d+

A $! bud'et must be de)e$oped+

T#s bud'et must tae !to accou!t t#t#at a-ect t#e rece)ed s'!a$+


13/20

L! 5ud'et 0Co!t!ued1


14/20

Feedline Loss

7eed$!e $osses occurs bet(ee! t#e rado a!d t#e a 7or t#e 'rou!d stato!, t#e s'!a$ bet(ee! t#e a!te

t#e rado must pass t#rou'# a s'!a$ sp$tter, t#e!a po$ar4ato! s(tc#, t#rou'# a!ot#er s'!a$ sp$t$ast$% t#rou'# a preamp$8er+

Pass!' t#rou'# t#e *eed $!e, t#e s'!a$ ($$ at#rou'# a tota$ o* 2B meters o* cab$e+ 7or t#estato! *eed $!e, t#s ($$ %e$d a tota$ $oss o*D


15/20

A!te!!a Ga! T#e a!te!!a 'a! s a 8'ure *or t#e co!ce!trato! o* t#e rado

drecto!+

I! t#s eamp$e a t%pca$ radato! patter! *or a ce!ter *ed dpos#o(!+ It ca! be see! t#at t#ere s !o radato! ema!at!' *romt#e a!te!!a (#ereas t#e stro!'est radato! s ema!at!' pert#e a!te!!a+

T#e 'a! *actor o* t#e sate$$te a!te!!a s at a mamum (#e!s po!t!' ts camera sde a!d t#e a!te!!a to(ards t#e Eart#


16/20

Crossed /po$e A!te!!a

Crossed dpo$e a!te!!a des'!ed+ T#e dpo$es are !orma$$% ore!tated

(t# respect to eac# ot#er+

Crcu$ar po$ar4ato! s ac#e)ed b%dr)!' t#e t(o dpo$es (t# a p#ased-ere!ce o* >?+

T#e top a!te!!a ! 7'ure 2 $eads b%>?, (#c# mea!s a r'#t9#a!d9crcu$arpo$ar4ato! s epected 0a$o!' t#epost)e 49as1+

T#e spac!' bet(ee! t#e dpo$es s !t#e order o* F@=?+

rosse po e ! e!!a


17/20

rosse po e ! e!!a0Co!t!ued1 To !crease t#e 'a! a$o!' t#e 49

as a $!ear arra% sco!structed, co!sst!' o* *ourcrossed9dpo$es (t# a spac!' o*F@


18/20

Losses ! .'!a$ Tra!sms

T#e po(ertra!smtted *romt#e tra!sce)er tot#e a!te!!a s

tra!s*ormed !toa! e$ectroma'!etc(a)e a!d #eat

7eed$!e $oss $oss t#at occubet(ee! t#e a!d t#e a!te

Po$ar4ato! L Propa'ato! L


19/20

.'!a$ to Nose Rato 0.N

It ')es a 8'ure *or #o( c$ear a rece)eds+

GM.K modu$ato! s used+

T#e prob$em arses because t#e tra!s

s'!a$ ($$ !e)er be t#e same as t#e res'!a$+ Loss t#rou'# propa'ato! a!d *ad!ter*ere!ce *rom !ose o* )arous or'(arp t#e or'!a$ s'!a$ be*ore t s rece)


20/20

Co!c$uso!

7rames are se!t *romtra!smtter to rece)er a!deac# *rame must beac!o($ed'ed or rejected+

Losses !c$ude propa'ato!

$osses, a!te!!a 'a!s,tra!smtted po(er, t#erma$!ose at t#e rece)er, a!ddsturba!ces t#rou'# t#eatmosp#ere+ .NR s#ou$d be

#'# to m!m4e $osses+

T#e modem padds o)

b%tes ! omp$eme!t

sc#eme *ocorrecto!+

telemetry, tracking and control

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