Models

612 and 625Loop Arrays

S p e c t r u m M o n i t o r i n g & M a n a g e m e n t S y s t e m s | B r o a d c a s t & C o m m u n i c a t i o n A n t e n n a s | C o m m u n i c a t i o n I n t e l l i g e n c e | D i r e c t i o n F i n d i n g S y s t e m s

© TCI—Al l r ights reserved | Dat a and specif icat ions subject to change without not ice | Not for distr ibut ion without pr ior permission from TCI .

TC I I n t e r n a t i o n a l , I n c . | 3 5 4 1 G a t e w a y B l v d . | F r e m o n t , C A 9 4 5 3 8 | + 1 . 5 1 0 . 6 8 7 . 6 1 0 0 | w w w . t c i b r . c o m

Electr ical ly Smal l AntennasE l e c t r i c a l l y s m a l l a n t e n n a s c a n b e u s e d t o a d va n t a g e i n a w i d e r a n g e o f r e c e i v i n g a p p l i c a t i o n s . Th e i n e f f i c i e n c i e s i n h e r e n t i n s m a l l a n t e n n a s h a ve t h e s a m e e f fe c t a s o t h e r s o u r c e s o f n o i s e o n t h e s i g n a l - t o - n o i s e r a t i o . W h e n ex t e r n a l n o i s e i s g r e a t e r t h a n t h e n o i s e f r o m a n t e n n a i n e f f i c i e n c y ( a n d i n t e r n a l e l e c t r o n i c s , i f p r e s e n t ) , a n a n t e n n a i s s a i d t o b e “ ex t e r n a l l y n o i s e l i m i t e d . ” I n t h i s c a s e , t h e h i g h e r l eve l o f ex t e r n a l n o i s e d o m i n a t e s t h e sys t e m s i g n a l - t o - n o i s e r a t i o , r e n d e r i n g t h e i n t e r n a l n o i s e i n s i g n i f i c a n t . Th u s , w h e n ex t e r n a l n o i s e i s r e l a t i ve l y h i g h , s m a l l r e c e i v i n g a n t e n n a s c a n w o r k a s w e l l a s f u l l - s i ze , f u l l y e f f i c i e n t a n t e n n a s . ( Th i s a l s o m e a n s t h a t f u l l y e f f i c i e n t a n t e n n a s n e e d b e l o c a t e d a t e l e c t r i c a l l y q u i e t s i t e s t o a c h i eve t h e i r f u l l p o t e n t i a l . )

Loop AntennasA l o o p a n t e n n a f u n c t i o n s a s a m a g n e t i c d i p o l e . A n i n c i d e n t e l e c t r o m a g n e t i c w a ve i n d u c e s a c u r r e n t i n t h e l o o p ; a m a t c h i n g t r a n s fo r m e r i n s i d e t h e l o o p c o u p l e s t h e i n d u c e d c u r r e n t i n t o a 5 0 Ω l o a d , e i t h e r a n a m p l i f i e r o r a l e n g t h o f c o a x r u n n i n g t o t h e r e c e i ve r .

O n e a d va n t a g e o f l o o p s ove r d i p o l e s i s t h e i r l o w i n p u t i m p e d a n c e . A l o o p ’s p e r fo r m a n c e i s r e l a t i ve l y u n a f fe c t e d by b u i l d i n g s , t r e e s , s n o w , e t c . , w h i c h t e n d t o s h o r t o u t r a d i a t i o n e n e r g y n e a r t h e e l e m e n t . M o r e ove r , s i n c e t h e r a d i a t i o n r e s i s t a n c e o f e l e c t r i c a l l y s m a l l a n t e n n a s i s l o w , m u t u a l e f fe c t s a r e g e n e r a l l y i n s i g n i f i c a n t , e n a b l i n g l o o p s t o b e c o n f i g u r e d i n va r i o u s a r r a ys t h a t t a i l o r t h e i r p e r fo r m a n c e t o p a r t i c u l a r r e c e i v i n g r e q u i r e m e n t s . Lo o p s a r e o f t e n a r r a ye d i n r o w s , o r “ a r m s ” o f fo u r , e i g h t , o r s i x t e e n l o o p s t o p r ov i d e a g r e a t va r i e t y o f r a d i a t i o n p a t t e r n s .

Th e b a s i c l o o p i s a l o w - i n d u c t a n c e a l u m i n u m t u b e , fe d a t i t s u p p e r m i d p o i n t v i a a b r o a d b a n d , p a s s i ve m a t c h i n g n e t w o r k . Th e n e t w o r k o u t p u t fe e d s a c o a x i a l c a b l e t h a t r u n s t h r o u g h o n e o f t h e t u b e s t o t h e b a s e w h e r e i t ex i t s t h e l o o p , a s s u r i n g e l e c t r i c a l b a l a n c e a t a l l f r e q u e n c i e s . Th e b r o a d b a n d m a t c h i n g n e t w o r k i s d e s i g n e d t o p r ov i d e a n o p t i m u m i m p e d a n c e m a t c h fo r m a x i m u m p o w e r t r a n s fe r ove r t h e 2 – 3 2 M H z b a n d w i d t h . A l l c o m p o n e n t s a r e w a t e r p r o o f a n d i m p e r v i o u s t o t h e e f fe c t s o f s a l t s p r a y a n d u l t r a v i o l e t r a d i a t i o n .

Radiat ion PatternsTh e a z i m u t h a l p a t t e r n o f a s i n g l e l o o p ( M o d e l 6 1 2 - 1 ) i s a f i g u r e - e i g h t ( r = c o s q ) a t t h e h o r i zo n , i n c r e a s i n g l y o m n i d i r e c t i o n a l a t h i g h e r a n g l e s o f a r r i va l , a n d v i r t u a l l y i n d e p e n d e n t o f a z i m u t h a t a n g l e s o f a r r i va l a b ove 4 5 d e g r e e s . Th e m a x i m u m g a i n o f a s i n g l e l o o p a t t h e h o r i zo n i s 5 d B i , t h e s a m e a s t h a t o f a ve r t i c a l l y p o l a r i ze d w h i p . Th e ove r h e a d g a i n i s a l s o 5 d B i , m a k i n g t h e s i n g l e l o o p a n exc e l l e n t c h o i c e fo r s h o r t - r a n g e c o m m u n i c a t i o n s . ( Th e w h i p h a s a n u l l ove r h e a d , l i m i t i n g i t s u s e f u l n e s s fo r s h o r t r a n g e s . ) Th e s i g n a l f r o m t w o o r t h o g o n a l l o o p s ( 6 1 2 - 2 o r 6 2 5 L ) c a n b e c o m b i n e d t o p r ov i d e a p e r fe c t l y o m n i d i r e c t i o n a l p a t t e r n a t a l l a z i m u t h s ( s i n 2 q + c o s 2 q = 1 ) , w i t h a g a i n o f 2 d B i .

Beam FormingS i g n a l s f r o m m u l t i p l e l o o p s c a n b e c o m b i n e d i n p h a s e , o r “ b e a m fo r m e d , ” w i t h a r e s u l t i n g d i r e c t i o n a l p a t t e r n h a v i n g a m a x i m u m g a i n a t s o m e a n g l e b e l o w t h e ze n i t h . A d d i n g l o o p e l e m e n t s i n c r e a s e s g a i n a n d d i r e c t i o n a l i t y . B e a m fo r m i n g i s a c c o m p l i s h e d by b r i n g i n g t h e fe e d c a b l e s f r o m e a c h e l e m e n t i n a n a r r a y t o a d e l a y / c o m b i n e r u n i t , o r b e a m fo r m e r , l o c a t e d a t t h e a r r a y ’s p hys i c a l c e n t e r . I n u n i d i r e c t i o n a l b e a m fo r m i n g , s i g n a l s f r o m e a c h e l e m e n t a r e d e l a ye d by m e a n s o f a p p r o p r i a t e l e n g t h s o f c o a x i a l c a b l e , o r d e l a y l i n e s , t h e n s u m m e d i n a hy b r i d c o m b i n e r . I n b i d i r e c t i o n a l b e a m fo r m i n g , t h e s i g n a l s a r e s p l i t a n d fe d i n t o t w o s e p a r a t e s e t s o f d e l a y l i n e s , t h e n s u m m e d i n t w o s e p a r a t e c o m b i n e r s .

• E a s y t o i n s t a l l

• E a s y t o t r a n s p o r t

• C o m p a c t , l o w p r o f i l e

• C o n f i g u r a b l e f o r m a n y d i f f e r e n t a p p l i c a t i o n s

• I d e a l f o r s m a l l s i t e s

FEATURES

Model 612-1

6 1 2 - 6 2 5 - 0 6 - 1 0 - 1 0

Ampli f iersA m p l i f i e r s a r e o f t e n u s e d w i t h l o o p a r r a ys t o b o o s t t h e s i g n a l p r i o r t o i n s e r t i o n i n t o t h e c a b l e r u n . Th ey a r e g e n e r a l l y r e c o m m e n d e d w h e n a t t e n u a t i o n i s exc e s s i ve o w i n g t o l o n g r u n s o f fe e d e r o r i n a d e q u a t e r e c e i ve r s e n s i t i v i t y . A m p l i f i e r s fo l l o w t h e hy b r i d c o m b i n e r s a n d d e t e r m i n e t h e sys t e m n o i s e l eve l a t t h a t p o i n t .

Th e s t a n d a r d a m p l i f i e r u s e d by TC I i n l o o p a r r a ys h a s 2 3 d B o f g a i n ; o t h e r va l u e s a r e a va i l a b l e t o m e e t s p e c i f i c r e q u i r e m e n t s . D C p o w e r i s f u r n i s h e d t o t h e a m p l i f i e r t h r o u g h t h e R F c o a x . H i g h - p a s s f i l t e r s t o b l o c k i n t e r fe r e n c e f r o m M F s t a t i o n s o r l o w - p a s s f i l t e r s t o b l o c k T V a n d F M s i g n a l s c a n b e i n c o r p o r a t e d i n t o t h e a m p l i f i e r a s r e q u i r e d .

TC I u s e s t h e b e s t a m p l i f i e r s a va i l a b l e ; n eve r t h e l e s s , a m p l i f i e r s a r e s u s c e p t i b l e t o ove r l o a d , s o m e t i m e s g e n e r a t e i n t e r m o d u l a t i o n p r o d u c t s , a n d a l w a ys a d d t o sys t e m n o i s e . U n l e s s a m p l i f i e r s a r e r e q u i r e d , c o nve r s i o n t o a p a s s i ve sys t e m m a y b e a d v i s a b l e .

Large Arrays of LoopsM u l t i p l e s m a l l a r r a ys a r e o f t e n c o m b i n e d i n r o s e t t e c o n f i g u r a t i o n s . O n e c o m m o n r o s e t t e c o n s i s t s o f fo u r b i d i r e c t i o n a l a r m s ex t e n d i n g f r o m a c o m m o n c e n t e r , w i t h e a c h a r m c o n s i s t i n g o f e i g h t l o o p s . Th i s 4 - a r m , 3 2 - l o o p c o n f i g u r a t i o n c a n p r o d u c e e i g h t b e a m s , o n e fo r e a c h 4 5 d e g r e e s o f a z i m u t h . S o m e a r r a ys u s e o n l y fo u r e l e m e n t s p e r a r m ; o t h e r s fo r l o n g - r a n g e a p p l i c a t i o n s u s e a s m a ny a s s i x t e e n fo r h i g h d i r e c t i o n a l g a i n a t l o w a n g l e s o f a r r i va l .

D e s i g n N o t e s

Th e fo l l o w i n g d e s i g n n o t e s s h o u l d b e c o n s i d e r e d i n p l a n n i n g a l o o p a r r a y :

Th e b e s t f r o n t - t o - b a c k r a t i o i s a c h i eve d by m a k i n g t h e a r r a y o n e - h a l f w a ve l e n g t h l o n g a t i t s l o w e s t f r e q u e n c y .

E l e m e n t s p a c i n g s h o u l d n o t exc e e d o n e - h a l f w a ve l e n g t h a t t h e h i g h e s t f r e q u e n c y t o p r eve n t g r a t i n g l o b e s i n t h e p a t t e r n .

Th e g a i n o f a n e n d - f i r e a r r a y i n c r e a s e s w i t h t h e s q u a r e r o o t o f i t s e l e c t r i c a l l e n g t h ; ove r a r a n g e o f 2 t o 3 2 M H z t h e a r r a y g a i n i n c r e a s e s by a fa c t o r o f fo u r ( 6 d B ) .

A m p l i f i e r s a d d sys t e m n o i s e ( 3 . 8 d B fo r t h e 2 3 d B u n i t ) .

Model 612Th e M o d e l 6 1 2 , w i t h a n o m i n a l d i a m e t e r o f t w o m e t e r s , i s t h e s m a l l e s t e l e m e n t i n t h e TC I fa m i l y o f l o o p a n t e n n a s . Th e 6 1 2 l o o p s t a n d s a b o u t 7 fe e t ( 2 . 2 m ) t a l l , d e p e n d i n g o n m o u n t i n g t y p e . M o d e l 6 1 2 l o o p s fo r t e m p o r a r y o r t r a n s p o r t a b l e a p p l i c a t i o n s a r e m o u n t e d o n s t e e l t r i p o d s ; fo r p e r m a n e n t o r h i g h w i n d / i c e a p p l i c a t i o n s , t h ey a r e m o u n t e d o n a l u m i n u m p o s t s b o l t e d t o c o n c r e t e p a d s .

Model 625 and Model 625LM o d e l 6 2 5 l o o p s h a ve a n o m i n a l d i a m e t e r o f t h r e e m e t e r s a n d a r e a r r a ye d i n t h e s a m e m a n n e r a s 6 1 2 l o o p s . Th e 6 2 5 e l e m e n t s a r e u s e d w h e r e t h e i r l o w e r n o i s e f i g u r e i s a d va n t a g e o u s , i e , a t q u i e t s i t e s a w a y f r o m u r b a n a r e a s ( s e e N o i s e F i g u r e Ta b l e ) .

Th e M o d e l 6 2 5 L i s a p a i r o f o r t h o g o n a l l o o p s m o u n t e d o n a c o m m o n a x i s . W i t h a d i a m e t e r o f 3 . 6 6 m e t e r s , t h e 6 2 5 h a s t h e l a r g e s t a p e r t u r e o f t h e TC I l o o p s . I n d i v i d u a l o u t p u t s f r o m e a c h l o o p p r ov i d e b i d i r e c t i o n a l s i g n a l s ; o u t p u t s c a n a l s o b e c o m b i n e d t o p r ov i d e o m n i d i r e c t i o n a l c ove r a g e .

Radiation Patternfor Model 612-1 and 625-1

(directive gain in dBi)

Plan and Elevation ViewModel 625 L

Specifications shown in tables

Plan and Elevation ViewModel 612-1 one element only

Model 612-2 both elements

Power Supply Mult icoupler Unit (PSM)A c o m b i n a t i o n p o w e r s u p p l y a n d H F m u l t i c o u p l e r u n i t ( PS M ) i s n o r m a l l y m o u n t e d i n a r a c k i n t h e r e c e i ve r b u i l d i n g . Th e PS M s u p p l i e s D C fo r t h e a r r a y p r e a m p s v i a t h e u s e r ’s R F c o a x . Th e PS M a l s o “ p i c k s o f f ” t h e R F f r o m t h e c o a x a n d d i s t r i b u t e s i t t o t h e s t a t i o n ’s r e c e i ve r s v i a a n u m b e r o f B N C c o n n e c t o r s ( u s u a l l y fo u r ) o n t h e b a c k o f t h e u n i t . S ys t e m s w i t h o u t a m p l i f i e r s n o r m a l l y r e t a i n t h e PS M c h a s s i s a s a c e n t r a l s o u r c e fo r t h e a r r a y ’s R F o u t p u t , w h i c h m a y i n c l u d e p o w e r s p l i t t e r s t o fe e d m u l t i p l e r e c e i ve r s .

Model Numbering SystemLo o p e l e m e n t s c a n b e a r r a ye d i n m a ny c o n f i g u r a t i o n s . TC I n o m e n c l a t u r e d e s c r i b e s t h e m a s fo l l o w s :

1 s t t e r m : n u m b e r o f a r m s i n t h e a r r a y

2 n d t e r m : e l e m e n t t y p e , 6 1 2 o r 6 2 5

3 r d t e r m : n u m b e r o f l o o p e l e m e n t s i n e a c h a r m

4 t h t e r m : s p a c i n g b e t w e e n e l e m e n t s , i n m e t e r s

5 t h t e r m : o p e r a t i o n m o d e o f t h e e l e m e n t ( U , u n i d i r e c t i o n a l , o r B , b i d i r e c t i o n a l )

Th u s , a n a r r a y o f fo u r b i d i r e c t i o n a l a r m s , e a c h h a v i n g e i g h t e l e m e n t s s p a c e d fo u r m e t e r s a p a r t w o u l d b e d e s i g n a t e d a s a M o d e l 4 - 6 1 2 - 8 - 4 - B . Th i s i s t h e 8 - d i r e c t i o n r o s e t t e d e s c r i b e d a b ove i n “ La r g e A r r a ys o f Lo o p s . ”

© TCI—Al l r ights reserved | Dat a and specif icat ions subject to change without not ice | Not for distr ibut ion without pr ior permission from TCI .

TC I I n t e r n a t i o n a l , I n c . | 3 5 4 1 G a t e w a y B l v d . | F r e m o n t , C A 9 4 5 3 8 | + 1 . 5 1 0 . 6 8 7 . 6 1 0 0 | w w w . t c i b r . c o m

SPECIFICATIONS

Power Supply Multicoupler UnitFrequency Range: 2–32 MHz

RF Impedance: 50Ω

VSWR: 1.2:1 maximum

Connection located on rear panel: BNC–jacks

Power Requirements: 115/220 V, 1.3/0.7 A, 50–60 Hz, single phase

Size: 19”x3.50”x13.75” deep

TCI Bi-directional End-Fire Loop ArraysFrequency: 2–32 MHz

Polarization: Vertical

Directive Gain:2 MHz 5 dBi5 MHz 8 dBi10 MHz 10 dBi20 MHz 13 dBi30 MHz 14 dBi

Direction of Radiation: Array is bi-directional and can receive signals simultaneously from either end-fire direction

Azimuth Beamwidth 5 MHz 86°

3 dB points 30 MHz 54°

Elevation Angle at upper 5 MHz 80°

3 dB points 30 MHz 30°

Front-to-back Ratio 13 dB minimum

(4–32 MHz)

Loops in Array 8

Array Length: 30 meters (98 feet)–612,

31 meters (102 feet)–625

Inter-Loop Spacing: 4 meters (13 feet)

Element Height: 2 meters (78 inches)–612 3.4 meters (134 inches)–625 4.4 meters (174 inches)–625L

Perfect groundAverage groundσ = 5mS/m,E1 = 10

TCI Model 1-612-8-4-U & TCI Model 1-625-8-4-UAzimuth and Elevation Directive Gain Patterns

10

10o

20o

30o

10o

20o

30o

500o

--5

2.0 MHz

10

10o

20o

30o

10o

20o

30o

500o

--5

5.0 MHz

10

10o

20o

30o

10o

20o

30o

500o

--5

30 MHz

10

10o

20o

30o

10o

20o

30o

500o

--5

10 MHz

10

10o

20o

30o

500o

--5

2.0 MHz

15 10

10o

20o

30o

500o

--5

5.0 MHz

15

10

10o

20o

30o

500o

-5

30 MHz

1510

10o

20o

30o

500o

-5

10 MHz

15

Frequency 612-1 612-8-4-B 625-8-4-B 625L

2 MHz 51.8 46.2 36.6 39.3 4 MHz 39.8 34.7 26.9 30.8 8 MHz 30.3 24.7 17.0 21.7 15 MHz 21.8 15.8 11.0 15.0 30 MHz 16.5 9.4 10.6 16.3

Frequency 612-1 612-8-4-B 625-8-4-B 625L

2 MHz 0.75 .43 1.30 0.91 4 MHz 1.5 .81 2.00 1.45 8 MHz 2.2 1.28 3.13 2.08 15 MHz 2.9 1.50 3.31 2.23 30 MHz 2.7 2.00 1.74 1.02

Frequency 612-1 612-8-4-B 625-8-4-B 625L

2 MHz 4.70 5.81 1.92 2.75 8 MHz 1.61 3.09 1.25 1.72 15 MHz 1.21 1.67 0.76 1.12 30 MHz 1.21 1.25 1.44 2.45

Noise figure (db) TCI loop arrays (systems include amplifier noise figure)

Effective height (m) TCI loop arrays at output of PSM 1-1 or PSM 2-1

Field strength incident on array required to drive amplifier to 1 dBcompression point (v/m)

Impedance (output): 50 ohms

Beam FormerOutput Connector: 2-type-N jacks

TCI Model 1-612-8-8-U (or B)Frequency: 2–16 MHz

Front-to-Back Ratio: 13 dB (2–16 MHz)

Directive Gain2 MHz 7 dBi5 MHz 10 dBi10 MHz 13 dBi16 MHz 14 dBi

TCI Model 612-1Composed of a single loop w/amplifier and power supply. Multicoupled outputs available, optionally.

Frequency: 2–32 MHz

Directive Gain: 5 dBi

TCI Model 612-2Composed of two single loops disposed orthogonally and fed either individually or with a hybrid combiner to form an omni azimuthal pattern. (Supplied with 1 amplifier and 1 power supply.) Multicoupled outputs available, optionally.

Frequency: 2–32 MHz

Directive Gain: 5 dBi when fed individually 2 dBi when fed with hybrid combiner.