Matlab and COTS instrumentations to reduce time and risk factors in design to the stand-alone QAM test system

In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the time to study the feasibility of a high speed digital communication test system. The result is a rack-and-stack QAM transceiver with the capability to characterize a device under test (DUT) in terms of bit error rate (BER) and error vector magnitude (EVM). Other characteristics of the DUT are also evaluated. The advantages of COTS rack-and-stack system are time reduction in development and return of capital investment, however, COTS stack-and-rack systems cannot cope with all aspects of high speed modern digital communications. Once the concept is proven, it will be transferred from rack-and-stack to a standalone test system which includes its own circuitry and embedded controller. The standalone digital communications test system is the ultimate goal of this study, since it provides the portability and speed required to support high speed modern digital communications. Advantages and disadvantage of stack-and-rack and standalone QAM test systems are presented.