How to minimize loss of Co-axial cable?

How to minimize the loss in co-axial cables? B'coz in our measurement, i am facing lot of problems with cable loss.i am working in the range 9kHz t0 18GHz

 

Are your signals of interest within the characteristics of the cable?

Is the cable/connectors constructed properly ... no shorts between shield and center, shorts between shield on one and and the other shield end, shorts between center conductor on one end and the other center conductor end.

Is the sending unit [both hot and return] connected to the cable [center conductor and shield]? Is the receiving unit connected appropriately?

Is the loss within the published "loss" for the cable?

 

After it has been manufactured there is almost nothing you can do. Cable loss is a fact of life. There are always more expensive alternatives like hardline.

What frequency range are you working with?

 

You didn't say what frequency you are working with. If you are in the 100's of MHz
you could check out the National Semiconductor LMHxxxx buffer amplifiers. I believe
they have application notes that discuss driving co-ax cables.

(* jcl *)

 

Ther is coax, and there is coax. Losses in RG-59 are about four times as great as with RG-6. Check the specs on the coax you are using. The parameter that is probably causing the greatest loss is the capacitance per unit of length. You might check an insure that the coax has the proper impedance for your application, too.