Receiver conducted susceptibility testing of spread 2 spectrum systems

Modern communication and navigation devices utilize spread spectrum technology to provide optimal use of the allocated RF spectrum and to minimize the effects of intentional interference and unintentional RF noise. The four most common spread spectrum techniques are briefly reviewed. Modern military communications equipment utilizes one or more of these techniques for signal transmission, while commercial applications are nearing completion for cellular telephones and direct broadcast satellite (DBS) applications. For the EMC engineer, the question of receiver performance is measured by testing to MIL-STD-461/462: test method CS03-intermodulation; CS04-rejection of undesired signal; and CS05-cross-modulation. Each of these tests are performed in the out-of-band RF spectrum and should not be confused with RF jamming tests that are performed in-band. Several approaches are discussed: the full test solution, the test and analysis solution, and the limited test solution