Evolution of the GSM air interface into wideband services

In this paper, a wideband evolution of cellular is presented-an evolutionary time-division multiple-access scheme, that combines GSM compatibility with high performance and wideband service capabilities. Several evolutionary steps are considered, including linear higher order modulation and multicarrier techniques. It enables higher bit rate services to be mixed with low bit rates in a combined scheme. The performance of the evolutionary scheme in terms of spectral efficiency is improved through the new modulation and diversity techniques. A high flexibility is achieved in the implementation and deployment of the scheme, since services ranging from low to high bit rates, can co-exist on the same carrier. This evolutionary path allows for successive introduction of new services and new features into an existing GSM system.