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From YouTube: Space and Satellite Symposium 2021 Vidya Gopalakrishna
Description
Xband beacon in AmbaSat
A
And
my
call
sign
is
kilo
the
number
four
victor
called
kilo.
I'm
super
excited
to
be
here
with
this
tiny
idea,
but
first
let
me
introduce
myself.
I
am
an
engineer,
but
I
write
what
does
that
mean
by
education?
I
am
a
communication
and
signal
processing
engineer.
I
worked
at
motorola
solution
as
an
lte
public
safety
communication
system
test
engineer,
but
people
around
me
always
said.
I
have
a
flair
for
tech.
Writing.
A
Looking
on
my
project
and
lab
request,
I
used
to
laugh
it
off,
but
when
the
opportunity
came
to
write
for
an
amazing
company
called
the
mathworks
for
the
rf
and
antenna
software,
I
jumped
at
it
and
I
have
never
looked
back
in
the
free
time.
I
am
the
mother
of
a
feisty
four-year-old
and
also
love
to
dance,
but
I'm
sure
you
guys
are
not
here
to
talk
about
me.
A
Let
us
see
how
I
got
into
this
project.
I
did
dabble
in
some
projects
for
the
adler
planetarium
to
rig
up
a
two-way
communication
system
for
their
high
altitude
purpose,
but
once
I
got
to
boston
for
the
writing
job,
I
have
not
been
very
successful
in
volunteer
work.
I
have
tried
to
start
oiri
was
introduced
to
me
by
openloaner.
A
I
signed
up
for
a
resist
as
his
research
assistant
program
for
the
open
lunar
and
was
interview.
Needless
to
say,
I
didn't
make
the
cut,
which
told
me
about
the
huge
amount
of
technology
that
I've
lost
touch
with.
While
writing
open
lunar
introduced
me
to
michelle
thompson
and
open
research
institute,
and
when
she
spoke
to
me
first,
she
asked
me
what
I
would
like
to
do.
A
I
told
her
something
tiny
that
is
easy
to
manage
with
the
many
hats
I
wear
in
a
date,
and
I
believe
she
took
me
literally
because
you
will
understand
when
you
walk
through
this.
This
is
exactly
also
when
I
decided
that
I
need
to
get
an
amateur
radio
license
in
the
beginning.
I
would
ask
michelle
what
is
the
point
of
a
project
when
she
explained
it
to
me
that
begin
to
test
expand
receivers
would
be
an
amazing
addition
to
the
amateur
radio
community.
A
A
So
how
do
we
get
this
to
space?
That's
where
all
this
tiny
comes
in?
Let's
shift
path
at
this
a
little
bit.
What
if
we
can
launch
a
satellite
into
space
that
is
programmed
by
us?
Space
is
no
longer
for
governments,
as
shown
by
jeff
resource
and
virgin
atlantic,
but
they
do
not
need
to
be
for
multi-billion
dollar
corporations.
A
Ambassador
just
helps.
People
like
us
touch
the
vastness
of
space
because
they
have
designed
a
tiny
satellite.
This
project
includes
me
michelle
thompson
and
dr
alan
johnston
who's
a
professor
at
villanova
university.
He
has
been
using
ambisides
in
high
altitude
balloon
launches
for
their
past
three
or
four
launches.
How
will
this
tiny
satellite
get
to
space?
It
uses
an
undesired
launcher
or
cubesat,
which
is
10
centimeters
by
10
centimeter
by
32
centimeters.
A
Leo
or
low
earth
orbit
is
relatively
close
to
it.
As
we
all
know,
it
lies
between
160
kilometers,
an
orbital
time
of
90
minutes
and
2000
kilometers,
which
is
an
orbital
time
of
120
minutes
to
maintain
stable
orbit
in
this
region
of
space.
Satellites
needs
to
have
an
orbital
velocity
of
7.8
kilometers
per
second
most
of
the
human
emissions
to
space
take
place
in
this
orbit,
except,
of
course,
the
moon
landings
and
also
the
international
space
station
conducts
its
operations
from
this
orbit.
A
The
ambisad
satellite
will
be
at
a
distance
of
about
230
kilometers
and
an
orbital
velocity
of
7.8
kilometers
per
second
meaning
that
our
tiny
little
satellite
will
revolve
around
the
earth
about
16
times
a
day.
Ambush
diet
will
stay
in
in
between
three
weeks
to
three
months.
It
depends
on
a
lot
of
factors,
including
drag
and
the
altitude.
A
What
are
the
advantages
of
leo?
There
is
a
shorter
orbital
period.
Latency
of
data
centered
received
is
lower,
launch
costs
are
much
lesser,
lower
rf
power
budget
and
better
frequency
reuse.
Some
challenges
are,
it
covers
much
lesser,
reaching
more
atmospheric
due
to
the
thermosphere
being
close
to
it.
The
satellite
will
travel
too
fast.
Sometimes
it
will
be
difficult
to
detect
or
very
little
time
to
test,
and
it
might
mean
to
establish
line
of
sight
with
the
expat.
A
Like
I
mentioned
earlier,
the
ambisac
can
stay
in
orbit
from
three
weeks
to
three
months.
Maybe,
and
even
though
this
is
an
advantage
in
one
way
as
it
would
not
create
space
debris
as
much.
The
disadvantage
is
that
we
do
not
have
much
time
to
test
our
expat
receivers
or
any
receiver
for
that
matter.
A
A
A
And
you
can
choose
from
six
different
sensors.
I
have
a
uni
sensor,
but
you
also
can
have
a
humidity
and
temperature
sensor
adjust
temperature
sensor,
ambient
light
gas
pressure,
temperature
sensor,
carbon
emissions,
gps,
etc.
The
sensors
you
choose,
you
can
solder
it
on
on
your
own
or
they
will
solder
it
and
give
it
to
you.
If
required,
the
satellite
can
be
powered
using
solar
cells
or
batteries.
If
it
is
earthbound,
it
is
batteries,
and
if
it
is
spacebound,
then
you
can
you
you
it's
better
to
use
solar
cells.
A
So
what
is
laura
lorawan
stands
for
low
power
wide
area
network.
This
network
is
most
popular
in
connecting
iot
or
internet
of
things.
Basically,
it
is
machine
talking
to
machines
using
the
internet.
The
frequency
used
by
laura
in
north
america
is
950
megahertz,
and
this
is
free.
That
means
you
don't
need
a
license
to
use
it.
The
maximum
transmitted
is
15
dbm
and
the
transmission
rate
is
very
low,
which
is
250.
A
Mbps
are
up
to
50
kbps
per
second,
even
because,
with
all
these
drawbacks,
laura
standard
is
supported
by
many
big
alliances
like
cisco
hp,
bosch
to
name
a
few
lorawan
network
is
similar
to
cellular
network.
Lorawan
devices
communicates
to
central
location
of
the
gateway.
The
gateway
is
a
screw
between
between
the
sensor
and
the
network
server.
A
Our
tiny
satellite,
the
ampersands,
are
capable
of
transmitting
data
to
over
five
thousand
earth-based
ttn,
all
things,
networks
which
are
spread
all
over
the
globe.
Now
let
us
see
why
we
want
to
change
this,
or
maybe
piggyback
this
using
a
microwave
and
beacon
microwave
bath.
Using
microwave
frequencies
are
authorized
to
all
mods
and
licenses.
Let
us
quickly
go
through
the
chart
before
we
get
into
the
details
as
we
go
higher
in
the
band's.
Throughput
is
also
higher
and
the
antennas
may
get
smaller,
but
we
will
require
line
of
set.
The
spectrum
band
is
larger.
A
For
example,
the
car
band
extends
from
26
gigahertz
to
40
gigabytes,
but
it
is
more
susceptible
to
rain
fading.
The
frequency
ranges
which
we
are
talking
about
is
expand
and
the
sea
band
allocated
damage.
Radio
is
5.6
to
5.9
gigahertz
for
the
c
band
and
10
to
10.5
gigahertz
for
the
expand.
These
frequencies
are
in
line
with
modern
communications
and
also
provide
the
ability
to
send
and
receive
data
at
high
speed.
A
So
what
are
the
advantages?
Larger
bandwidth
higher
gain
higher
directivity?
You
can
transmit
audio
media
and
data
simultaneously
smaller
antennas,
smaller
microwave
components,
low
cost
because
of
that
low
power
consumption
and
what
are
some
of
the
disadvantages
line
of
sight
is
required
most
of
the
time
feeding
due
to
atmospheric
conditions
such
as
rain,
snow
fog,
large
number
of
reflections
by
flattened
metal
surfaces
and
it
the
signal
can
also
be
diffracted
by
solid
objects.
A
Now
that
you
have
understood
what
we
are
trying
to
do
with
this
project,
let
us
take
a
look
at
a
simple
link
budget
analysis.
Let
us
say
the
basic
analysis
of
the
system.
We
will
compare
the
link
budget
and
the
received
power
and
the
carrier
to
noise
density
ratio
of
laura
van
an
expat.
Please
do
bear
in
mind
that,
because
this
is
a
working
problem,
the
values
are
just
approximate.
A
A
This
is
in
db,
total
transmission
path,
clause
or
tpl
is
free
space,
back
loss,
polarization
loss,
atmospheric
loss
and
tropospheric
attenuation,
and
these
are
just
some
of
the
losses
that
I
have
added
over
here.
Receive
power
or
the
link
power
budget
is
the
eirp
mine
is
a
total
transmission
per
closer
tpl
and
the
receiver
feeders.
A
You
can
also
add
the
satellite
antenna
gain
divided
by
the
system
noise
temperature
to
this,
but
I
don't
have
some
of
the
values.
So
this
is
again
just
an
approximation.
Last
is
carrier
to
noise
density.
It
is
a
ratio
of
performance
of
a
satellite
link.
It
is
a
ratio
of
carrier
power
to
noise
power.
It
is
adding
all
the
gains
and
then
subtracting
the
past
losses
and
the
system
temperature.
A
Here
we
will
look
at
the
downlink
value,
though
the
total
value
is
the
carrier:
noise
ratio
of
up
character,
noise
ratio
density
uplink
as
well
as
doubling.
Now
we
will
look
at
the
doppler
frequencies
chipped.
We
are
modifying
these
equations.
We
are
going
to
consider
the
losses
due
to
doppler
frequency
shift
in
these
equations.
A
Now
this
equation
consists
of
you
can
see.
The
frequency
doppler
shift
depends
upon
the
velocity
of
the
satellite,
the
radius
of
the
earth,
the
transmitting
frequency
coverage
angle,
the
speed
of
the
electromagnetic
wave,
as
well
as
the
relative
distance
between
the
satellite
and
the
earth
dominant.
A
I
have
assumed
a
coverage
of
13
degrees
for
this
calculation
when
you
look
at
the
values.
So
this
is
how
the
receive
power
of
the
lean
power
equation
changes.
Now
we
have
two
kinds
of
losses:
the
loss
due
to
the
total
power,
the
total
path,
transmission
loss,
as
well
as
the
last
due
to
the
frequency
shift.
A
All
the
calculations
are
in
db,
and
this
is
how
the
carrier,
noise
density
carrier
to
noise
ratio
density,
also
changes
when
you
add
the
modified
one.
These
are
the
values
that
I
have
received
after
the
calculations.
As
you
can
see
that
there's
a
considerable
chip.
This
is
a
work
in
progress,
so
the
amplification
has
not
been
added.
Please
keep
in
mind.
I
have
considered
a
coverage
of
13
degrees,
which
might
not
be
true
for
a
tiny
satellite
like
in
such
circumstances.
A
For
me,
one
of
the
biggest
and
the
hardest
parts
of
this
project
was
finding
the
right
paths
to
suit
my
need,
first
and
foremost,
while
building
a
career.
In
writing.
I
had
lost
touch
with
the
advances
in
communication
and
technology,
even
a
link
budget
analysis,
which
is
quite
easy,
took
some
time
for
me
because
of
the
years
that
I've
lost
touch
with
this
and,
of
course,
life
got
in
the
way.
A
When
dr
johnston
and
michelle
spoke
to
me
about
this
project,
I
was
very
excited,
but
after
some
thought
I
was
completely
clueless
what
I
can
use
to
make
this
a
reality.
Even
after
a
couple
of
months,
I
hadn't
gotten
a
little
better,
as
you
all
can
understand,
the
size
of
the
satellite
and
the
power
available
is
very
less.
While
I
was
wrapping
my
head
around
this.
I
came
through
lots
of
paths
thing
about
these
parts.
A
The
thing
about
these
parts
that
we
are
looking
for
for
a
beacon
is
that
most
of
these
chips,
gw
chips
are
not
for
microwave.
They
are
for
wi-fi.
So
why
can't
we
repurpose
this
chips?
You
will
see
the
first
chips,
as
you
can
see,
is
microchip
one
md,
one:
three:
seven
zero.
This
is
an
eight
channel
ultra
low
channel
aaa
channel
ultra
low
cw
transmitter
with
a
beam
performer.
It's
a
good
option.
The
second
chip
is
a
texas
instrument.
A
A
A
A
So
consists
of
an
hp100,
an
lm7805
which
is
a
voltage
regulator,
an
sma
connected
power,
source
and
tools,
a
switch
in
our
case,
not
sure
if
we
will
need
this.
A
microwave
sensor,
hp
5
for
hp100
is
a
part
of
a
short
range
motion
detector.
The
motion
uses
a
dielectric
resonator
as
a
signal
generator.
This
motion
sensor
is
designed
for
10.5
to
5,
which
is
a
little
about
the
frequency
that
we
can
use
in
the
expand.
A
With
this
in
allows
tuning
to
design
frequency
of
10.369
gigahertz,
the
dro
can
be
connected
to
an
xma
connector,
which
would
be
used
to
connect
to
a
transmit
antenna.
The
power
source
we
required
is
a
12
volt
supply,
which
we
can
use
the
lm7805
to
reduce
it,
zero
fighter
as
a
voltage
rate
to
bring
down
it
to
about
5
volts
right,
and
that
is
a
maximum
supply
voltage
that
hb100
can
handle
the
signal
generator
radiates
to
space
and
the
antennas
are
part
chantanas.
A
On
this
side
of
the
hp
100,
there
is
transmit
antennas
and
receive
antenna,
so
it
is
a
transceiver
basically,
and
we
can
also
tune
this
by
using
the
metal
screw
over.
This
and
tuning
it
there
are
many
facebook
communities
that
use
this
in
different
ways
to
generate
a
signal
or
even
in
the
receiver,
to
test
a
signal.