Sum
mar
y to
dat
e•
HF
prop
agat
ion
and
spac
e w
eath
er e
nvir
onm
ent
–af
fect
s HF
spec
tacu
larly
(fla
res)
,–
and
may
als
o be
unn
otic
ed (v
aria
bilit
y),
–it
unde
rlies
all
HF
syst
ems,
–an
d it
is in
esca
pabl
e.
•B
ut H
F U
sers
’–
equi
pmen
t may
be
too
inse
nsiti
ve to
resp
ond,
–m
ay h
ave
little
idea
how
they
are
bei
ng a
ffec
ted,
and
little
ince
ntiv
e to
find
out
mor
e.
Spec
ialis
ed S
ervi
ces
•N
ot a
ll H
F us
age
is b
enig
n•
For i
nsta
nce:
–Ill
egal
tran
smis
sion
s nee
d to
be
track
ed–
Jam
min
g ne
eds t
o be
avo
ided
–Se
cure
com
mun
icat
ions
nee
d to
be
esta
blis
hed
•Th
ese
are
exam
ples
whe
re a
suita
ble
prop
agat
ion
mod
el is
a n
eces
sity
–Th
is is
the
prop
agat
ion
adva
ntag
e.
Whe
re n
ow?
•“P
oor r
elia
bilit
y an
d lo
w c
ircui
t qua
lity
are
the
acce
pted
nor
m;
–H
F co
mm
unic
atio
ns c
ontin
ues t
o ha
ve a
bad
repu
tatio
n,–
past
tech
nolo
gy, a
vaila
ble
unde
rsta
ndin
g le
ad to
mod
est r
elia
bilit
y, su
bjec
t to
sign
al d
isto
rtion
,in
terf
eren
ce a
nd lo
w d
ata
rate
s.” (
from
Bar
clay
,IE
S200
2).
•B
ut n
ew te
chno
logy
off
er h
uge
adva
ntag
es.
–D
igita
l sig
nal p
roce
ssin
g (D
SP)
–A
dapt
ive
syst
ems,
auto
mat
ed c
ontro
l–
Impr
oved
freq
uenc
y m
anag
emen
t
Dig
ital H
F
•D
igita
l HF
can
brin
g re
volu
tiona
ry c
hang
es.
•A
dapt
ive
HF
syst
ems
–ch
oice
of a
nten
na, f
requ
enci
es, e
tc–
Aut
omat
ic L
ink
Esta
blis
hmen
t (A
LE).
•D
igita
l bro
adca
stin
g to
repl
ace
anal
ogue
syst
ems
–be
ing
test
ed n
ow, a
nd m
ost i
mpr
essi
ve (e
.g.,
Dig
ital
Rad
io M
ondi
ale,
DR
M),
–ai
m is
2 b
its/H
z in
a 1
0 kH
z ch
anne
l (an
ITU
issu
e).
•Fu
rther
dig
ital s
igna
l pro
cess
ing,
–ne
w m
odem
s, ne
w p
roto
cols
, new
wor
ld.
HF
Dat
a R
ates
•U
p to
10
year
s ago
–da
ta ra
tes o
f ~75
bits
/sec
com
mon
.
•M
ore
rece
ntly
–ra
tes o
f 2.4
kbi
ts/s
ec a
nd 4
.8kb
its/s
ec re
ache
d.
•O
n be
nign
skyw
ave
chan
nels
–64
kbi
ts/s
ec is
reac
hed.
•A
nd –16
kbits
/sec
is d
esire
d.
HF
Inte
rnet
is o
ne o
bjec
tive
driv
ing
this
.
Tim
e di
sper
sion
at H
F
Mul
tipat
h de
lay
time
0.2
0.4
0.6
0.8
1.0
100
1000
10000
100000
Path
dis
tanc
e (k
m)
[afte
r Ba
iley,
D.K
., IR
E Tr
ans.
Ant
.Pro
p., A
P-7,
195
9, p
.398
}]
f/MUF
0.5
ms
1 m
s
2 m
s
4 m
s
max
Sign
al fa
ding
•If
the
iono
sphe
re w
as u
ncha
ngin
g th
e si
gnal
ampl
itude
wou
ld b
e co
nsta
nt•
In p
ract
ice,
fadi
ng is
cau
sed
by:
–va
riatio
ns in
abs
orpt
ion;
–irr
egul
ariti
es, f
ocus
sing
and
def
ocus
ing
–m
ultip
ath
–ch
ange
s in
pola
risat
ion
•R
apid
fadi
ng -
mul
tipat
h (1
0 H
z)•
Slow
est f
adin
g - a
bsor
ptio
n ( τ
= m
aybe
hou
rs)
Fadi
ng c
hara
cter
istic
s
Non
-per
iodi
cV
aria
tions
in M
UF
Seco
nds t
o se
vera
l hou
rsFl
are
effe
cts
Min
utes
to a
n ho
urTI
Ds
10 –
100
secs
(Far
aday
) pol
ariz
atio
nfa
ding
seco
nds
Mov
ing
irreg
ular
ities
< se
cond
Smal
l sca
le ir
regu
larit
ies
Fadi
ng p
erio
dC
ause
s
US
Def
ence
per
spec
tive
•“H
F C
omm
unic
atio
ns p
lays
a v
ital r
ole
in p
rovi
ding
the
tact
ical
com
mun
icat
ions
requ
ired
to e
nsur
e su
cces
s in
Nav
y, Jo
int,
and
Alli
ed m
ilita
ry o
pera
tions
. In
deed
, in
aty
pica
l Bat
tle G
roup
/ A
mph
ibio
us R
eady
Gro
up’s
Com
mun
icat
ions
Pla
n, a
ppro
xim
atel
y 30
to 4
0 pe
rcen
t of
the
spec
ified
circ
uits
are
eith
er a
n H
F pr
imar
y ci
rcui
t or a
nH
F se
cond
ary
circ
uit.
It is
, how
ever
, a c
halle
ngin
g an
dde
man
ding
freq
uenc
y sp
ectru
m in
whi
ch to
ope
rate
, fro
mbo
th a
tech
nica
l and
war
fight
ing
pers
pect
ive.
”•
Ref
: Hig
h Fr
eque
ncy
(HF)
Aut
omat
ic L
ink
Esta
blis
hmen
t(A
LE) T
rans
ition
Pla
n. T
ech.
Doc
., 19
95.
ALE
– a
RTC
E te
chni
que
•In
the
past
,–
a sk
illed
radi
o op
erat
or e
stab
lishe
d co
mm
unic
atio
ns–
and
adju
sted
ope
ratin
g pa
ram
eter
s.–
Toda
y, th
is fu
nctio
n m
ay b
e au
tom
atic
.•
ALE
syst
ems c
hoos
e th
e be
st H
F ch
anne
l with
out a
ssis
tanc
e.–
Each
HF
ALE
syst
em h
as a
num
ber o
f cha
nnel
s.–
The
larg
er th
e fr
eque
ncy
set,
the
bette
r (sa
y 10
to 1
2)•
Link
Qua
lity
Ass
essm
ent i
s lim
ited
by sm
all f
requ
ency
sets
.•
Car
eful
cho
ices
her
e sh
ould
incl
ude
prop
agat
ion
adv
ice.
–Pe
riodi
cally
, a st
atio
n at
tem
pts t
o lin
k on
eac
h of
its f
requ
enci
es,
–m
easu
res t
he si
gnal
qua
lity,
–an
d st
ores
the
qual
ity sc
ores
.•
Whe
n a
call
is in
itiat
ed, t
he ra
dio
chec
ks it
s “m
emor
y”–
dete
rmin
es th
e be
st q
ualit
y fr
eque
ncy
to th
e de
sire
d st
atio
n.–
Atte
mpt
s to
link
on th
at fr
eque
ncy,
–A
nd c
ontin
ues t
ryin
g on
the
next
bes
t fre
quen
cy, a
nd so
on,
–un
til a
link
is e
stab
lishe
d.
ALE
- ex
perim
ent
•Se
t-up
(Tilb
rook
and
Coo
k, ~
1993
)–
10 fr
eque
ncie
s, tw
o m
odem
s (si
ngle
tone
and
39-
tone
2.4
kb/
s), o
nM
elbo
urne
-Ade
laid
e (6
50 k
m) p
ath
•R
esul
ts–
ALE
est
ablis
hed
links
and
pas
sed
data
•G
ener
ally
6 fr
eque
ncie
s day
time
and
1 or
2 a
t nig
ht w
ere
avai
labl
e–
64%
succ
ess f
indi
ng a
use
ful f
requ
ency
on
sing
le to
ne m
odem
–80
% su
cces
s with
the
39-to
ne m
odem
–Th
e si
ngle
-tone
mod
em p
erfo
rmed
bet
ter o
n m
any
ocas
sion
s•
Dis
cuss
ion
–A
LE L
ink
Qua
lity
Ass
essm
ent (
LQA
) poo
rly c
orre
late
d w
ith B
it Er
ror
Rat
e–
Non
-opt
imum
per
form
ance
–O
utpe
rfor
ms m
edia
n pr
edic
tions
, but
HF
pred
ictio
ns a
llow
ed so
me
unlik
ely
freq
uenc
ies t
o be
elim
inat
ed
ALE
ope
ratio
nal l
imita
tions
•A
LE a
utom
ates
HF
linki
ng a
nd fr
eque
ncy
sele
ctio
n–
It do
es n
ot re
plac
e a
train
ed o
pera
tor (
who
kno
ws t
heeq
uipm
ent,
ante
nnas
, etc
); a
man
agem
ent i
ssue
•A
LE a
llow
s a n
ovic
e to
use
the
syst
em–
How
ever
, tw
o tra
ined
ope
rato
rs m
ay b
e ab
le to
set u
p a
link
fast
er; a
man
agem
ent i
ssue
.•
Dep
endi
ng o
n eq
uipm
ent
–A
LE m
ay n
ot d
eter
min
e if
a ch
anne
l is a
lread
y in
use
; apr
ocur
emen
t iss
ue.
•A
LE c
anno
t im
prov
e pr
opag
atio
n co
nditi
ons
–A
LE o
nly
wor
ks a
s wel
l as t
he a
vaila
ble
freq
uenc
ies a
llow
it to
; a p
ropa
gatio
n pr
oble
m.
Furt
her A
LE is
sues
•A
LE n
eeds
seve
ral f
requ
enci
es to
be
effe
ctiv
e–
But
this
may
incr
easi
ng H
F in
terf
eren
ce–
Red
uce
the
num
ber o
f fre
quen
cies
, by
taki
ng p
ropa
gatio
nco
nditi
ons i
nto
acco
unt
• O
pera
tiona
l tim
e an
d fr
eque
ncy
sele
ctio
n co
mpe
te–
Red
uce
the
num
ber o
f fre
quen
cies
, by
taki
ng p
ropa
gatio
nco
nditi
ons i
nto
acco
unt,
is a
dvan
tage
ous
•A
LE a
nnou
nces
its p
rese
nce
as it
soun
ds o
n po
tent
ial
oper
atio
nal f
requ
enci
es (j
amm
ing,
surv
eilla
nce)
–Sh
orte
n tim
e ne
eded
to te
st p
ath
(tech
nolo
gy so
lutio
n)–
Shad
ow th
e en
emy
(pro
paga
tion
optio
ns)
The
way
forw
ard
•“H
F pe
rfor
man
ce d
epen
ds o
n ho
w w
ell t
he sy
stem
desi
gn c
ompe
nsat
es fo
r the
pro
paga
tion
chan
nel.”
•“I
n es
senc
e th
e w
avef
orm
aim
s to
com
pens
ate
for
mul
tipat
h an
d D
oppl
er e
ffec
ts, w
hich
can
com
prom
ise
the
sign
al in
tegr
ity.”
•“S
ucce
ss d
epen
ds c
ritic
ally
on
a go
odun
ders
tand
ing
of th
e ra
dio
chan
nel m
ultip
ath
and
Dop
pler
cha
ract
eris
tics.”
(Can
non,
Ang
ling
& L
undb
org,
Rev
iew
s of R
adio
Sci
ence
200
2)
HF
path
pro
paga
tion
•H
F pr
opag
atio
n pa
th is
cha
ract
eriz
ed b
y m
ultip
ath
prop
agat
ion
and
fadi
ng.
•Th
e si
gnal
trav
els o
ver s
ever
al p
aths
or m
odes
to th
e re
ceiv
er–
via
sing
le a
nd m
ultip
le re
flect
ions
from
the
E, E
, F la
yers
and
may
be E
s–
incl
udin
g gr
ound
refle
ctio
ns–
In tw
o or
thog
onal
pol
aris
atio
ns, a
nd b
y hi
gh a
nd lo
w ra
y pa
ths.
•Pr
opag
atio
n tim
es o
ver t
he p
aths
are
diff
eren
t,–
the
rece
ived
sign
al m
ay c
onsi
st o
f sev
eral
mul
tipat
h co
mpo
nent
s–
spre
ad in
tim
e by
up
to se
vera
l mill
isec
onds
.•
Ave
rage
iono
sphe
ric la
yers
hei
ghts
may
incr
ease
or d
ecre
ase,
–in
trodu
cing
diff
eren
t fre
quen
cy (D
oppl
er) s
hifts
–on
eac
h m
ultip
ath
com
pone
nt.
•Th
e io
nosp
here
is a
lso
turb
ulen
t–
caus
ing
Dop
pler
spre
ad (f
adin
g) o
f eac
h co
mpo
nent
,–
and
a re
sulta
nt fa
ding
of t
he c
ompo
site
rece
ived
sign
al.
•A
ll of
thes
e ef
fect
s pro
duce
mul
tiplic
ativ
e si
gnal
dis
torti
on a
ndde
grad
atio
n of
the
perf
orm
ance
of c
omm
unic
atio
n sy
stem
s.
Dig
ital H
F C
hann
els
Io
nosp
heric
cha
nnel
nee
ds to
be
mod
elle
d,m
easu
red
and
char
acte
rised
in te
rms o
f:•
SNR
•M
ultip
ath
dela
y•
Dop
pler
spre
ad•
Dop
pler
shift
(The
bit
erro
r rat
e fo
ra
parti
cula
r mod
emco
nfig
urat
ion
is a
func
tion
of th
ese
four
par
amet
ers)
Mil-
Std-
188-
110A
ser
ial,
sho
rt in
terle
aver
, 12
00bp
s
02
46
81
01
21
41
61
82
02
42
83
23
64
0
0
1
2
3
4
5
6
7
8
9
10
-10
-8-6-4-20246810121416182022242628303234363840
SNR
(dB
)
Dop
pler
Spr
ead
(Hz)
Mul
tipat
h (m
s)
-10
010203040
Exam
ples
of m
odem
s
1487
-04
1
2
6
10
14
18
24
32
40
0
1
23
45
67891011121620
–10
01020304050
0.1
0.5
1.5
Dop
pler
spre
ad (H
z)
Mul
tipat
h (m
s)
S/N (dB)
FIG
UR
E 4
Exa
mpl
e pe
rfor
man
ce su
rfac
e fo
r a
2 40
0 bi
t/s8-
PSK
seri
al to
ne m
odem
1487
-06
1
2
6
10
14
18
24
32
40
0
1
23
45
67891011121620
–10
01020304050
0.1
0.5
1.5
Dop
pler
spre
ad (H
z)
Mul
tipat
h (m
s)
S/N (dB)
FIG
UR
E 6
Exa
mpl
e pe
rfor
man
ce su
rfac
e fo
r a
300
bit/s
8-PS
K se
rial
tone
mod
em
DR
M B
road
cast
s•
DR
M =
Dig
ital R
adio
Mon
dial
e•
FM q
ualit
y in
the
AM
ban
d–
And
it w
orks
•R
elie
s on
mai
ntai
ning
rece
iver
/mod
em in
the
low
SN
R re
gion
for s
yste
m p
erfo
rman
ce•
One
met
hod,
–ha
ve re
fere
nce
rece
iver
s pla
ced
with
in th
eta
rget
are
a–
com
bine
the
obse
rvat
ions
–an
d ad
just
mod
ulat
ions
sche
mes
in re
al ti
me.
Iono
gram
s &
Iono
sond
es•
Site
Pri
ority
: −
This
is a
spar
se n
etw
ork,
all
sites
hav
e hi
gh p
riorit
y −
Cur
rent
stra
tegy
: diff
eren
t typ
es o
f ion
oson
de a
nd 2
per
site
. •
Sam
plin
g:
− Ev
ery
5 m
inut
es (e
xcep
t whe
re sp
ecia
l loc
al c
ondi
tions
or p
rogr
ams d
icta
t eot
herw
ise; o
nly
one
stat
ions
affe
cted
at p
rese
nt)
• E
quip
men
t rel
iabi
lity:
−
4D/IP
S42
is el
derly
and
obs
olet
e, a
lso n
o m
agne
toio
nic
sepa
ratio
n −
CA
DI i
s a (r
elat
ivel
y) lo
w p
riced
Can
adia
n io
noso
nde
− 5D
is lo
w p
riced
, IPS
-bui
lt io
noso
nde
• A
naly
sis
− D
ata
reco
rded
for A
SFC
– fo
F2 m
ain
char
acte
ristic
−
An
hour
ly e
stim
ate
is pr
oduc
ed fr
om m
edia
n of
5-m
inut
e
auto
scal
ed e
stim
ates
−
Out
lier t
rimm
ing
− O
ther
met
hods
, pos
sibl
y be
tter t
han
this,
are
pos
sible
.
Rea
l Tim
e Io
nosp
heric
Mod
ellin
g
A F
utur
e G
row
th A
rea
•R
eal-t
ime
mod
els
–io
noso
nde
data
ises
sent
ial.
•Fe
w v
iabl
e al
tern
ativ
es,
–es
peci
ally
for t
hebo
ttom
side
iono
sphe
re.
•St
atio
n de
nsity
is p
oor,
–an
d ge
tting
WO
RSE
.
Cur
rent
iono
sond
es a
vaila
ble
at S
EC
War
saw
Nar
ssar
ssua
qFa
irfor
d
Wal
lops
*M
illst
one
Hill
*Eg
lin*
Wak
kana
iM
anzh
ouli*
Dye
ssTr
omso
*M
agad
an*
Dix
onSo
ndre
stro
m*
Col
lege
*
San
Vito
*Ly
ckse
le*
Cho
ngqi
ng*
Sale
khar
d*K
waj
alei
n*C
hilto
n*
Rom
eK
ing
Salm
on*
Bou
lder
*
Ram
ey*
Kok
ubun
jiB
eijin
g*
Qaa
naaq
*Ju
liusr
uh*
Bak
er L
ake*
Pt A
rgue
llo*
Jica
mar
ca*
Ath
ens*
Osa
nG
uang
zhou
*A
shkh
abad
*
Oki
naw
aG
oose
Bay
*A
scen
sion
*
Nor
ther
n H
emis
pher
e
Mad
imbo
Loui
sval
eV
anim
o*Le
arm
onth
*
Tow
nsvi
lle*
Hob
art*
Scot
t Bas
eG
raha
mst
own
Pt S
tanl
ey*
Dar
win
*
Pr M
ores
by*
Chr
istc
hurc
h*
Nor
folk
Is. *
Cas
ey*
Mun
darin
g*C
anbe
rra*
Maw
son
Cam
den*
Mac
quar
ie Is
. *B
risba
ne*
Sout
hern
Hem
isph
ere
38/2
8 N
orth
ern
Hem
isph
ere
stat
ions
20/1
5 So
uthe
rn h
emis
pher
e st
atio
nsTo
tal /
(ava
ilabl
e 16
-Sep
tem
ber-
2004
)
Mis
sing
Dat
a So
urce
s?•
Obl
ique
iono
gram
s–
Onl
y ha
ve o
ne p
ath
to N
ew Z
eala
nd, n
eed
mor
e–
Use
ful t
o at
leas
t che
ck c
urre
nt m
aps
•To
tal E
lect
ron
Con
tent
–C
urre
ntly
, no
site
s use
d in
real
tim
e–
Scin
tilla
tion
info
rmat
ion
in re
al ti
me
may
soon
be
avai
labl
e•
HF
fixed
freq
uenc
y be
acon
reco
rdin
gs–
Nee
d to
mon
itor k
now
n ch
anne
ls to
val
idat
e pr
edic
tions
•H
F no
ise
obse
rvat
ions
–Is
it w
orth
mon
itorin
g th
is a
t our
site
s?•
Cha
nnel
occ
upan
cy–
Is it
wor
th m
onito
ring
this
at o
ur si
tes?
•H
F qu
ality
est
imat
or–
mos
t for
ecas
ts a
re tr
ying
to o
ffer
this
info
rmat
ion
01
23
45
6-0
.4
-0.20
0.2
0.4
0.6
0.81
Auto-correlation
Hrs
4 th
roo
t of
N -
dayt
ime
Spor
adic
E –
tem
pora
lly h
ighl
yva
riabl
e
Flar
e D
urat
ion
A w
ell-s
ited,
mod
ern
HF
sys
tem
will
be
affe
cted
by
a C
-cla
ss fl
are
01
23
45
6110
Flare class relative to M1
dura
tion
of fl
are
(hou
rs)
Not
e: A
C-c
lass
flar
e ca
n af
fect
a w
ell-s
ited,
sens
itive
HF
syst
em
HA
P C
hart
and
Aur
oral
Ova
l
•Ex
ampl
e sh
ows f
requ
enci
esfo
r con
tact
ing
Perth
.•
The
NO
AA
/TIR
OS
auro
ral
data
are
use
d to
pro
duce
this
disp
lay.
•Th
e "b
ars"
at t
he b
otto
m sh
owth
e ex
tent
, pos
ition
and
inte
nsity
of t
he a
uror
al o
val.
•Th
e cu
rved
line
repr
esen
tsai
rcra
ft fli
ght p
ath
on th
e gr
eat
circ
le b
etw
een
Mel
bour
ne a
ndC
ape
Tow
n.
Em
ail p
rodu
cts
Emai
l Ser
vice
D
escr
iptio
n So
urce
of I
nfor
mat
ion
Sent
ip
s-au
rora
-ale
rt Po
ssib
ility
of A
uror
al E
vent
Lo
cal m
agne
tom
eter
, KA
us ≥
6
875
ips-
clg-
radi
o-sw
eep-
even
t R
adio
Sw
eep
even
ts d
etec
ted
at C
ulgo
ora
Cul
goor
a sp
ectro
grap
h ra
dio
swee
p ev
ents
93
ips-
dhfp
r D
aily
HF
Prop
agat
ion
Rep
ort
Iono
sphe
ric /
flare
16
9 ip
s-dh
fpr-
euro
A
utom
ated
Dai
ly E
urop
ean
HF
Prop
agat
ion
Rep
ort
Iono
sphe
ric /
AFr
11
ip
s-ds
gr
Dai
ly S
olar
and
Geo
phys
ical
Rep
ort
SDF,
SG
AS,
GO
ES X
-ray
flux
& p
roto
ns,
loca
l ion
osph
eric
& m
agne
tom
eter
dat
a.
313
ips-
flare
-ale
rt Fl
are
Ale
rt G
OES
X-r
ay fl
ux
205
ips-
geo-
war
ning
G
eoph
ysic
al W
arni
ng
Fore
cast
er d
ecisi
on
231
ips-
geos
tat-s
yste
m
GEO
mag
netic
STo
rm A
lert
Trac
king
Sys
tem
SO
HO
, Geo
War
n, A
CE,
loca
l mag
netic
dat
a 18
ip
s-hf
-war
ning
H
F W
arni
ng
Fore
cast
er d
ecisi
on
192
ips-
iflux
-dai
lyva
lues
D
aily
Qui
et S
un R
adio
Flu
xes
from
Lea
rmon
th
Lear
mon
th fl
ux o
bser
vatio
ns
26
ips-
mag
-ale
rt M
agne
tic A
lert
KA
ustra
lia ≥
5
162
ips-
msg
r M
onth
ly S
olar
and
Geo
phys
ical
Rep
ort
Arc
hive
d so
lar,
mag
netic
iono
sphe
ric d
ata
155
ips-
prot
on-a
lert
Prot
on A
lert
GO
ES p
roto
n flu
xes (
10 M
eV)
99
ips-
si-a
lert
Expe
rimen
tal G
eom
agne
tic S
udde
n Im
pulse
D
etec
tion
Loca
l mag
neto
met
er d
ata
8
ips-
ssn-
pred
ictio
ns
Obs
erve
d an
d Pr
edic
ted
Sola
r Ind
ices
Lo
cal i
nspi
ratio
n 26
8 ip
s-sw
f-ale
rt SW
F A
lert
GO
ES X
-ray
flux
11
6 ip
s-sw
p-al
ert
Sola
r win
d ge
omag
netic
act
ivity
pre
curs
or
AC
E EP
AM
47-
65 K
eV p
roto
n ch
anne
l 19
ip
s-sw
s-al
ert
Expe
rimen
tal S
olar
Win
d Sh
ock
Ale
rt A
CE
sola
r win
d da
ta
123
ips-
tinde
x-pr
edic
tions
IP
S O
bser
ved
and
Pred
icte
d T
Indi
ces
Loca
l ins
pira
tion
50
ips-
wgr
W
eekl
y G
eoph
ysic
al R
epor
t A
rchi
ved
mag
neto
met
er d
ata
49
ips-
whf
pr
Wee
kly
HF
Prop
agat
ion
Rep
ort
Arc
hive
d io
nosp
heric
dat
a 14
0 ip
s-w
sgr
Wee
kly
Sola
r and
Geo
phys
ical
Rep
ort
Loca
l mag
netic
, ion
osph
eric
dat
a, fl
are
info
. fro
m S
GA
S.
144
Ips-
ursig
ram
IP
S U
RSI
GR
AM
cod
ed m
essa
ges:
UG
EOA
, U
FOFH
, UR
ASP
, UPA
TV, U
GEO
R
Loca
l ion
osph
eric
dat
a, sp
ectro
grap
h ev
ents
an
d fo
reca
sts
?
Perf
orm
ance
Indi
cato
rs?
• a
grow
ing
cust
omer
bas
e
• in
crea
sing
ly d
iver
se re
quire
men
ts
• sub
ject
ive
inte
r-ce
ntre
fore
cast
com
paris
ons
• ego
, gut
feel
and
pes
sim
ism
IPS
Hom
epag
e H
its
•An
early
web
site
exp
erie
nce
dem
onst
rate
s sig
nific
ant i
nter
est.
•The
larg
e sp
ike
was
a C
ME
even
t rep
orte
d by
NA
SA.
•The
ram
p is
whe
n ne
w se
rvic
es w
ere
intro
duce
d.
Agr
eed
Met
ric: C
usto
mer
Pat
rona
ge
•Po
sitiv
e–
It do
es g
ive
som
eco
nfid
ence
•N
egat
ive
–C
onta
ins i
ncre
asin
g W
ebus
age
trend
–Pr
oble
m o
f wha
t is a
HIT
?–
Cus
tom
ers d
on’t
alw
ays
know
wha
t is b
est f
or th
em.
–N
ot o
bjec
tive.
Agr
eed
Met
ric: C
usto
mer
s in
Nee
d
•A
s act
ivity
incr
ease
s,m
ore
cust
omer
s use
site
,–
or sa
me
cust
omer
s ret
urn
mor
e fr
eque
ntly
•IP
S is
pro
vidi
ngso
met
hing
that
is n
eede
d.•
This
is a
key
indi
cato
r at
pres
ent.
-8-7
-6-5
-4-3
-2-1
01
23
45
67
812
000
1400
0
1600
0
1800
0
2000
0
Average Number of hits on Website
epo
ch (
day
s)
-8-6
-4-2
02
46
805101520253035404550
Su
per
po
sed
epo
ch: A
p >
47
(blu
e) v
s A
vera
ge
We
b hi
ts (
red)
Ap
Agr
eed
Met
ric: A
ccur
acy
•Po
sitiv
e A
spec
ts–
An
agre
ed a
ppro
ach
–Ti
me
serie
s ind
icat
espr
ogre
ss a
gain
st st
anda
rd–
Educ
atio
nal
–O
bjec
tive
mea
sure
that
can
be re
calc
ulat
ed
•N
egat
ive
Asp
ects
–D
epen
ds o
n th
e ch
osen
stat
istic
–C
ause
of c
hang
es d
epen
don
oth
er v
aria
bles
and
know
ledg
e
QU
ALIT
Y -
ACC
UR
ACY
IPS
ION
O F
OR
ECAS
TS
020406080100
JAN 00
APR
JUL 00
OCT
JAN 01
APR
JUL 01
OCT
JAN 02
APR
% forecasts within 20 units
Acc
urac
yio
nofo
reca
sts
Targ
etac
cura
cy02
Fore
cast
ing:
Tim
es S
cale
s
Effe
ct
Tim
e sc
ale
Eval
uatio
n So
lar c
ycle
de
cade
Em
piric
al M
odel
Se
ason
al
mon
ths
Empi
rical
Mod
el
Stor
ms
Few
day
s va
riabi
lity
Diu
rnal
cyc
le
day
Empi
rical
Mod
el
Spor
adic
E
Few
hou
rs
noth
ing
Flar
es
Min
utes
to fe
w h
ours
w
arni
ngs
TID
s M
inut
es to
hou
rs
varia
bilit
y Te
rmin
ator
m
inut
es
Empi
rical
mod
el +
va
riabi
lity
Fadi
ng
Mill
isec
onds
to se
cond
s st
atis
tics
“Sir
Edw
ard
App
leto
n” b
y R
onal
d C
lark
“…. T
hese
fact
s ind
uced
App
leto
n to
sugg
est
info
rmal
ly to
the
Serv
ices
, soo
n af
ter t
heou
tbre
ak o
f war
, tha
t ion
osph
eric
fore
cast
ing
of ra
dio
cond
ition
s mig
ht b
eus
eful
. …..
The
situ
atio
n ro
se to
a h
ead
whe
n a
num
ber o
f pla
nes,
dest
ined
for a
leaf
let r
aid
on G
erm
any,
flew
stra
ight
up
the
Nor
th S
ea u
ntil
they
ran
out o
f pet
rol.”
Ch.
8. P
130
His
tory
: Maj
or L
imita
tions
in
the
past
• La
ck o
f C
ritic
al D
ata
• Sl
ow E
xcha
nge
of
Ava
ilabl
e D
ata
• Po
or U
nder
stan
ding
of
the
Sci
ence
• Li
mite
d A
bilit
y to
Com
mun
icat
e Fo
reca
sts
• Si
mpl
e N
on-S
peci
fic S
ervi
ces
The
New
Mill
eniu
m F
orec
aste
rs
• W
e ob
serv
e ev
eryt
hing
bet
ter,
• an
d ge
t it i
n re
al ti
me,
dec
oded
, as a
pic
ture
.
• Com
mun
icat
ions
are
won
derf
ul
• Ser
vice
s are
far m
ore
com
plex
His
tory
: Val
idat
ion
of F
orec
asts
(the
excu
ses)
•Pr
e-19
90–
Har
dwar
e w
as d
omin
ant
(tele
type
, cha
rt pe
ns, e
tc.).
–N
o se
rious
atte
mpt
to m
onito
r the
acc
urac
y of
man
ual m
etho
ds.
–Th
ose
impl
emen
ted
gave
pos
itive
resu
lts, p
rovi
ng it
was
poi
ntle
ss.
•Po
st 1
990
–In
crea
sing
num
bers
of s
mal
l tas
ks, w
hich
had
to b
e ex
ecut
ed in
parti
cula
r way
s and
spec
ial t
imes
, dro
ve a
utom
atio
n.–
Aut
omat
ion
of th
e bu
lk (a
ll?) p
rodu
cts m
eant
ver
ifica
tion
was
subo
rdin
ate
to fa
ult d
etec
tion
and
bug
rem
oval
.–
Dur
ing
this
per
iod,
the
ASF
C p
rodu
cts w
ere
subj
ectiv
ely
chec
ked
and
mai
ntai
ned
near
to m
anua
l ser
vice
del
iver
y ac
cura
cy.
•C
urre
nt–
The
expl
osio
n of
dat
a no
w a
vaila
ble
by in
tern
et d
rive
s aut
omat
ion
and
now
cast
ing.
–A
s aut
omat
ion
beca
me
wel
l ent
renc
hed
and
relia
ble,
dat
a flo
ws
beca
me
the
emph
asis
.–
This
cur
rent
pha
se is
app
roac
hing
com
plet
ion.
–Th
ere
is n
ow p
oten
tial f
or a
cha
nge
in e
mph
asis
.
Type
s of
Val
idat
ion
•Su
bjec
tive
veri
ficat
ion
- a c
omm
on a
ppro
ach
–D
ebug
ging
all
aspe
cts o
f sys
tem
.–
Doe
s it l
ook
right
? Is
dat
a flo
win
g, a
nd is
it a
ccur
ate?
–Fo
reca
st is
inco
rrec
t, re
vise
met
hods
.–
Loca
l exp
erie
nce,
self-
corr
ectio
n.–
Subj
ectiv
e sy
stem
s ten
d to
be
base
d on
self-
asse
ssm
ent
•O
bjec
tive
veri
ficat
ion-
–D
escr
iptiv
e di
spla
ys.
–C
ompa
re o
utpu
ts w
ith o
utco
mes
and
mak
e st
atis
tical
tabu
latio
ns.
•B
otto
m L
ine
–Es
sent
ial f
or se
rious
cus
tom
ers’
con
fiden
ce.
Subj
ectiv
e M
easu
res
of V
erifi
catio
n
•A
gro
win
g cu
stom
er b
ase
•In
crea
sing
ly d
iver
se re
quire
men
ts &
requ
ests
– w
e m
ust b
e do
ing
som
ethi
ng ri
ght,
they
wan
t mor
e
•A
utom
ated
pro
duct
s–
loca
l rec
ipie
nt re
ceiv
es a
nd c
heck
s a c
opy
•M
anua
lly v
erify
thro
ughp
ut; e
xam
ples
:–
shoc
k in
AC
E lo
g, c
heck
out
put
–a
dist
urba
nce
is e
xpec
ted,
car
eful
che
ckin
g
•su
bjec
tive
inte
r-ce
ntre
fore
cast
com
paris
ons
•eg
o, g
ut fe
el a
nd p
essi
mis
m
Type
s of
Obj
ectiv
e Ve
rific
atio
n
•D
escr
iptiv
e di
spla
ys•
Com
paris
on a
gain
st a
n ag
reed
met
ric,
–cu
stom
er u
sage
–le
vel o
f acc
urac
y
•C
ompa
rison
with
a st
anda
rd•
Stat
istic
al ta
bula
tions
–pr
obab
ility
of c
orre
ct fo
reca
sts
–er
ror d
istri
butio
ns
•A
ver
ifica
tion
sche
me
is p
roba
bly
usel
ess i
ffo
reca
ster
s cas
t for
ecas
ts to
get
goo
d sc
ores
.
Com
paris
on o
f Sy
dney
and
Bou
lder
A
p F
orec
asts
in
199
9
05
1015
2025
3035
4045
5055
6065
7075
8085
9095
100
05101520253035404550556065707580859095100
R =
0.7
4
Com
paris
on o
f Pre
dict
ed A
indi
ces
for 1
999
Predicted A for Centre A
Pre
dict
ed A
for C
entre
D
Rea
lity
Doe
s N
ot A
gree
!!
020
4060
8010
0020406080100
R =
0.4
0
Com
paris
on o
f Ap
inde
x w
ith C
entre
A p
redi
ctio
n (1
999)
Predicted A for Centre A
Ap
inde
x
020
4060
8010
0020406080100
R =
0.2
8
Com
paris
on o
f Ap
inde
x w
ith C
entre
D p
redi
ctio
n (1
999)
Predicted A for Centre D
Ap
inde
x
May
- Ju
ne 1
999
Com
paris
on fo
r foF
2
-20
-15
-10
-50
510
1520
020406080100
120
140
160
180
200
220
240
260
280
300
320
340
percentage * 10
auto
scal
ed -
man
ually
sca
led
foF2
(0.1
MHz
bin
s)
Brisb
ane
5D
-20
-15
-10
-50
510
1520
020406080100
120
140
160
180
200
220
240
260
280
300
320
340
percentage * 10
auto
scal
ed -
man
ually
sca
led
foF2
(0.1
MH
z bi
ns)
Can
berr
a C
adi
-20
-15
-10
-50
510
1520
020406080100
120
140
160
180
200
220
240
260
280
300
320
340
percentage * 10
auto
scal
ed -
man
ually
sca
led
foF2
(0.1
MH
z bi
ns)
Hob
art 4
D
-20
-15
-10
-50
510
1520
020406080100
120
140
160
180
200
220
240
260
280
300
320
340
percentage * 10
auto
scal
ed -
man
ually
sca
led
foF2
(0.1
MH
z bi
ns)
Cam
den
4C
Aut
osca
ling:
Can
berr
a 5D
& C
AD
I
•Tw
o io
noso
ndes
per
site
•G
ive
two
“loo
ks”
at th
eio
nosp
here
.•
Upp
er is
CA
DI,
low
er 5
D•
Gen
eral
ly si
mila
r•
But
cle
arly
not
iden
tical
.•
Thes
e ar
e ty
pica
l err
ors.
Sum
mar
y•
HF
pred
ictio
ns w
ill a
lway
s be
requ
ired
for p
lann
ing
–C
urre
nt so
ftwar
e is
inte
nded
for a
nalo
gue
syst
em d
esig
n–
Dig
ital s
yste
ms n
eed
augm
ente
d pl
anni
ng a
dvic
e•
Prop
agat
ion
know
ledg
e ca
n be
a m
ajor
adv
anta
ge–
Espe
cial
ly if
you
hav
e an
adv
ersa
ry•
Rea
l-tim
e pr
opag
atio
n ad
vice
is v
alua
ble
–In
crea
sing
the
valu
e of
est
ablis
hed
obse
rvat
ion
site
s•
Iono
sond
es fo
r ins
tanc
e–
Ass
ista
nce
for d
igita
l sys
tem
s rem
ains
unc
lear
•Fo
reca
stin
g se
rvic
es a
ppea
r to
mer
ge w
ith re
al-ti
me?
–D
on’t
fall
into
this
trap
–A
war
ning
of w
hat m
ight
hap
pen
is a
lway
s hel
pful
Som
e R
esou
rces
•J.
M. G
oodm
an: H
F C
omm
unic
atio
ns (1
992)
•M
. Hal
l, L.
Bar
clay
& M
Hew
itt (1
996)
: Pro
paga
tion
of R
adio
wav
es•
R D
Hun
suck
er a
nd J
K H
argr
eave
s: T
he H
igh-
Latit
ude
Iono
sphe
re a
nd it
s Eff
ects
on
Rad
ioPr
opag
atio
n (2
003)
•IT
U: T
he Io
nosp
here
and
its E
ffec
ts o
n R
adio
wav
ePr
opag
atio
n (1
998)
•N
. Mas
lin: H
F C
omm
unic
atio
ns (1
987)
•L
F M
cNam
ara:
The
Iono
sphe
re: C
omm
unic
atio
ns,
Surv
eilla
nce,
and
Dire
ctio
n Fi
ndin
g (1
991)