Design guidelines Ultra Low Loss cable assemblies.

Chapter Title 1. Selection criteria for high frequency coaxial cables 1.1 Cable specifications 2. Selection criteria for high frequency connectors 2.1 Assembly V.S.W.R. for typical configurations 2.2 Power derating for altitude and temperature 3. Cable assembly codification 4. Basic high frequency formulas

Design guidelines Ultra Low Loss cable assemblies.

1. Selection criteria for high frequency coaxial cables The recommended high frequency coaxial cable family is selected by the cable selection chart for mechanical properties. The specific cable is selected on the electrical properties and diameter.

SELECT A CABLE Flexlife Crush resistance Frequency range Insertion loss Power Diameter/Bending radius

Design guidelines Ultra Low Loss cable assemblies.

1.1 Cable specifications

Design guidelines Ultra Low Loss cable assemblies.

2. Selection criteria for high frequency connectors The recommended high frequency connector type is selected by the connector selection chart by frequency range.

SELECT A CONNECTOR Frequency range Male/Female Straight/90 degrees/Swept Power handling Mechanical properties

Design guidelines Ultra Low Loss cable assemblies.

2.1 Assembly V.S.W.R. for typical configurations Assembly V.S.W.R. or return loss is influenced to a large extent by the specific assembly configuration (length and connector types) in combination with the frequency and bandwidth. Also the test method and equipment in use can have some influence. Because of that it is impossible to provide a single V.S.W.R. specification that would be applicable to all possible combinations of cables and connectors. However the following table can be used as a guideline. The mentioned values (table 1) apply to the standard connector series SMA, TNC and Type N in the precision or higher frequency versions of these series. When specific assembly requirements and test methods have been fixed, it is often possible to guarantee lower V.S.W.R. values. Also some connector and/or length combinations (extremely short or extremely long) may result in higher values. To be certain please contact us with your specific requirements.

Table 1

Cable Assembly V.S.W.R. Straight / Swept

Connectors Two Angle Connectors Mixed Connectors Frequency

Range (GHz) Guar. Typical Guar. Typical Guar. Typical

DC to 2 1.15 (1.10) 1.25 (1.15) 1.20 (1.10)

2 to 4 1.20 (1.10) 1.30 (1.20) 1.25 (1.20)

4 to 8 1.30 (1.20) 1.40 (1.30) 1.35 (1.30)

8 to 12 1.35 (1.25) 1.45 (1.35) 1.40 (1.35)

12 to 16 1.35 (1.25) 1.45 (1.35) 1.40 (1.35)

16 to 18 1.35 (1.25) 1.45 (1.35) 1.40 (1.35)

18 to 26.5 1.45 (1.35) 1.55 (1.45) 1.50 (1.40)

26.5 to 65 Call us for details

Design guidelines Ultra Low Loss cable assemblies.

2.2 Power derating for altitude and temperature The power handling of microwave connectors is depending on the frequency, ambient temperature and altitude. In the below graphs the power handling of the most commonly used microwave connectors on sea level at 20ºC is shown and the derating factors for altitude and temperature.

Frequency (GHz.)

2.4 mm

K

3.5 mm

SMATNCP

NP

7 mm

HN

0 3 6 9 12 15 18 210

20

40

60

80

100

25 50 75 100 125 150 175 200

Altitude (10³ meters)

Ambient Temperature (°C)0-25

120

140

Design guidelines Ultra Low Loss cable assemblies.

3. Cable assembly codification

assembly range

C D G

Customer specific assembly ALPEN standard stock assembly Gigalink standard stock assembly

cable code A 24 UFP A 40 UFP A 50 UFP A 81 UFP

A 150 UFP A 26DT FP

A 52 FP

020 040 050 081 150 026 052

A 80 FP A 120 FP A 180 FP

A 26SDT TFE A 26 TFE A 52 TFE

A 60 P

080 121 182 027 028 053 060

A 80 P A 90 P A 120 P A 180 P A 250 P

A 60 PPP A 90 PPP

083 090 120 180 250 061 091

protection

0 1 2 3 9

no protection flexible spring with PUR jacket (GP)

flexible hose (FN) flexible hose with PUR jacket (FG)

other

range connector 1 & 2 code

A B C D

DQ E F G H

range 2,4mm

K(2,9mm) 3,5mm SMA BMC TNCP

NP -

AP7

freq. 40 40 33

26,5 10 18 18 -

18

code I J K L M N O P Q

range MCX BMA

SSMA SMB

- BNC SMP

MMCX 7/16

freq. 6 18

26,5 4 - 4 40 6

7,5

code R S T U V W X Y Z

range SSIS

C SC HN - - -

SMC -

freq. 40 11 11 4 - - -

10 -

type connector 1 & 2

code 0 1 2 9

type male straight male swept male 90 deg

other

code 3 4 5 6

type female straight screw female straight flange

female swept female straight other

Design guidelines Ultra Low Loss cable assemblies.

4. Basic high frequency formulas 1) Insertion losses Loss (dB) = 10 log ¹º (P out/P in) - 10 dB = 10 % of P in lost - 20 dB = 1 % of P in lost - 30 dB = 0.1 % of P in lost 2) Return losses (VSWR) Losses due to reflected power Return loss (dB) = 10 log ¹º (P in/P reflected)

Return losses (dB) VSWR - 23.10 - 20.80 - 19.08 - 17.70 - 16.55 - 15.56 - 14.71 - 13.97

1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50

3) Cut off frequency Maximum frequency of signal propagation versus the cable dimensions F max = 191 (d+D) Ep d = diameter inner conductor

D = diameter dielectric Ep = dielectric constant

Design guidelines Ultra Low Loss cable assemblies.