Effective evaluation of link quality using error vector magnitude techniques

Abstract

Bit error rate (BER) is an accepted figure of merit in the industry for the characterization of transmission link quality and communications systems in general. While useful as a conceptual figure of merit, it suffers from a number of practical drawbacks that compromise its value as a standard test in manufacturing or maintenance. This paper discusses the use of error vector magnitude (EVM) and its relationship to BER to develop a foundation that will help in formulating and implementing a sound and cost-effective test strategy for component, sub-system and system test in communications systems, such as mobile cellular, satellite and wireless data networks.