NIST 垂直极化单杆天线校准指南说明书

o f th i s app l i e d vo l tage , the l ength and diame te r o f the tr ansmi t t ing
antenna ,
the
di s tance
be tween
the
tr ansmi t t ing antenna
and
the
A UT ,
Te c h .
N ote
1 34
7 ,
28
pag e s
(Jan u ary
CO D E N zNTNO E F
W U S
.
.
GOVE RNMENT
P R I NTI N G
OFFICE
AS H I NGTON : 1 99 1
u e e e u e e e W For sale by the S
p
ri n t
nd
nt of D oc
m
nts U S Gov rn m
,
.
nt
Printin g
Office ,
ash in gton , D C 2 04 02-932 5
CONTENTS
Ab s tr ac t
1 .
INTRODU CTION
2 .
THEORETI CAL BAS I S
z
3 .
antennas , and i t i s g iven by [ 5 ]
z
-j 30 1 0 s i n (ߣ )
'j fir l Ie
r
1
'j flr z
e
r
2
20 °S (fl2 )
whe r e
r
1
[ d2
(z 2)
r
2
[d
(z
2)
r
[ d2
2
2
fl
I
O
( in
A)
is
the bas e
cur r ent o f the monopo le , and A i s the fr ee - spac e
polar ized
monop o l e
antennas over
the fr equency r ange o f 30 kHz
to
300
MH z .
The fac i l i ty i s l o c a te d at the D ep ar tment o f C omme r c e B oul de r L ab or a t o r i e s , Boulder , Color ado .
S TANDARD F I ELD METHOD FOR CALIB RATING MONOPOLE S
D escr iption of t h e Equipment
Te s t Pr oce dur e
Antenna Fac t or
Cal ibr at i on Uncer ta inty
4 .
fr equency
r ange
of
30 kH z
to
30 0 MH z .
The unc er ta inty in the
antenna fac tor
o f the antenna under
tes t (A UT) i s now i
1 dB .
Ke y wo r ds : an tenna fac to r ; c a l ib r a t i on ; e l e c tr omagne t i c f i e l d ; monop o le antenna ; open fi e l d s i te ; s tandar d fi e l d .
The ge ome tr y f o r a th in cyl indr i c al monop o l e antenna l o c at e d over a
per fect
gr ound
is
shown
in
fi gur e
1 .
Th e monop o l e ha s l ength 2 and i s
as sume d t o have a s inus o i dal cur r ent di s tr ibut i on
The monop o le
r adi ate s ver t i c al and hor iz ontal e l ec tr i c fi e l d c omp onents , E and E , and a
as the f i e l ds o f a c ente r - fe d dip o l e o f l ength 2 2 in fr e e s pac e . The
exp r e s s i on f o r E in e q ( 1 ) a s sume s a s inus o i dal cur r ent di s tr ibut i on on the 2
tr ansmi t a cw e l ec tr omagne t i c fi e l d . The vo l tage supp l i e d to the
tr ansmi t t ing antenna i s measur e d : The f i e l d s tr ength i s c a l cul a te d in te r ms
CONCLUS I ONS
5 .
REF ERENCES
' APPENDI A : SAMPLE TES T REPORT FOR A VERT I CAL MONOPOLE
iii
' N I ST CALI B RAT I ON PROCEDURE F OR VERT I CALL POLARIZ ED
z
p
ho r i z onta l magne t i c f i e l d c omp onent , H Only the ve r t i c a l e l e c tr i c f i e l d
E ( in V/m) i s r e qu i r e d f o r c al ibr at i on o f ve r t i c al ly p o l ar i z e d monop o l e z
monopole
and th i s as sump t i on i s val i d f o r 2 5 A /A
' The
i np u t
impedanc e
of
the
monop o l e
Z
mo n
( in
) i s one hal f that o f a
dipo le o f length 21 in fr e e space
ver t i c a l monop o l e antenna t o c a lcula te the ver t i c a l e l e c tr i c
f i e l d . Thi s me tho d i s us e d a t the NI ST op en fi e l d s i te in the
s i te . Thi s measur ement s i te i s us e d over the fr e quency r ange o f 30 kHz to
300 MHz f o r ver t i c al ly p o l ar i z e d antenna s .
At the NI ST f ie ld s i te a thin cyl indr ic al monop o l e antenna i s us e d to
wave l ength .
Al l di s tanc e s and the wave l ength a r e given in me ter s .
By image
the or y the EM f i e l ds in the ha l f s p ac e ab ove the gr ound p l ane a r e the s ame
Boulder , CO 80 30 3
Th i s r ep or t de s c r ib e s the the or e t i c al b as i s and te s t p r o c e dur e
f or ver t i c al ly p o lar i z ed monop o l e antenna cal ibr at i ons at the
MONOPOLE ANTENNAS ,
30
'
KH Z
TO
30 0
MH Z
l l D C Came
.
.
a s en C uz and i l l E B L r
,
.
.
JE
r
,
..,源自DA H..
Elec tr omagne tic Fie lds D ivi s ion Nat ional Ins t i tute o f S tandar ds and Techno logy
1 .
INTRODU CT I ON
The pur p o s e o f th i s r epor t i s t o pr ovi de do cumenta t i on f o r the met ho d , equipment , and fac i l i ty emp loyed by NI ST f o r cal ibr at ing ve r t ic al ly
. Lyon s, D i r ctor
Issu ed u Jan ary 1 99 1
Nati on al In stitute of Stan d ards a n d Tech n ology Tec h n i cal Note 1 34 7
N atl .
I n st .
Stan d .
Tec h n ol .,
and
the
he i gh t o f the AUT ab ove the gr ound p l ane . The gr ound p l ane i s as sume d t o b e p er fe c t ly conduc t ing .
2 .
THEORETI CAL BAS I S
Nat i onal Ins t i tute o f S tandar ds and Te chno l o gy ( NI S T ) . Th e
s tandar d fie ld me thod app l ie s the theor e t ical e quat i ons o f a
B ou l d e r Col orado 80303-332 8 ,
' W U S
.
D EPARTM E NT O F
COMMERCE,
R
obe rt
A .
Mosbach er ,
S e c reta ry
e NA T IO NA L I N STITUTE O F STA N D A R D S A N D TE C H N OLOG Joh n ,
Th i s me tho d invo lve s
e s tab l i shing r e fer enc e cw fi e l ds at sp e c i fi e d f i e l d s tr ength l eve l s f o r
spe c i fi e d di s tance s fr om the tr ansmi t t ing monop o l e on the NI S T op en - fi e l d
The me thod us ed at NI S T f o r cal ibr at ing ver t i c al ly p o l ar i z e d monopo l e
ant ennas i s c al l ed the s tandar d f i e l d me tho d [ 1
N IST Cal i bration Proced u re fo r Ve rt i ca l l y Po l a r i zed Mon opole A n ten n as,
30 kHz to 300 M H Z
E l ectrom ag n eti c Fi e l d s D ivi s i on Ce nte r for E l ectron i cs a n d E lectri cal E n g i n ee ri n g N ati on al E n g i n ee ri n g Laboratory Nati on al I n stitute of Stan d ard s an d Tec h n ol ogy