In general we recommend using the shortest cable that is suitable for your application.
Sma cable insertion loss.
Insertion loss db max.
Loss is a length multiplier so a 200 ft length would have twice the loss shown above and a 50 ft length would have half the loss.
There are 3 main causes of insertion loss.
Sma coaxial connectors crimp terminations for flexible cable.
Sma connectors feature stainless steel or brass construction and a 36 threaded coupling which offers high performance in a compact design.
Cable status codes status code description c custom s stock n non stock connector specifications series impedance frequency range insertion loss sma rp sma 50ω 0 12 4ghz 0 04db max mcx rp mcx 50ω 0 6ghz mmcx 50ω 0 6ghz cable length tolerance cable assembly capabilities connector choices for cable assemblies connector choices for.
Shorter cables show a greater effect.
This multiplier factor is why you should keep cable installation lengths between radios and antennas as short as practical.
Each cable has a low vswr of 1 4 from dc to 18 ghz as well as a low insertion loss see the table below.
Reflected losses dielectric losses and copper losses.
The graph above shows the insertion loss for sma to sma microwave cables.
Reflected losses are those losses caused by the vswr of the connector.
The smp connector can mate directly to a gpo connector while the sma connector can mate directly to a 2 92 mm 3 5 mm or k connector.
To a lesser extent the loss tangent of the eptfe is also a function of temperature.
Test frequency 6 0 ghz military specifications mil c 39012 mil c 83517 sma.
Most adapters have a very low loss one that cannot be measured without some pretty good test equipment.
This measurement was taken at 18 ghz.
Insertion loss expressed in db is defined as 10 log po pi where po power out and pi power in.
Insertion loss change is in percent db relative to 0 db change at 25 c.
Insertion loss change is primarily due to the change in conductivity of the silver with temperature.
A number of years ago i ran into a situation with an installation that had used some radio shack pl 259 and pl 258 connectors in the commercial 450 mhz band in which each connector had an insertion loss of just over 1 db per connector.
The shaded region denotes the specified operating frequency range of these cables.