3GPP LTE: Introducing Single-Carrier FDMA

摘要

Close on the heels of IEEE's new 802,16e standard -- better known as Mobile WiMAX~(TM) -- follows the response from the Third-Generation Partnership Project (3GPP) in the form of its Long-Term Evolution (LTE) project. We featured WiMAX~(TM) in Issue Three of Agilent Measurement Journal and in this article we explore what LTE aims to bring to the wireless ecosystem. After considering the broader aspects of LTE, we take a closer look at the uplink, which uses a new modulation format called single-carrier frequency-division multiple access (SC-FDMA). These are interesting times because it is rare that the communications industry rolls out a new modulation format. From both a technical and practical point of view, there is much to understand, examine and evaluate in the capabilities and benefits that SC-FDMA brings to LTE. SC-FDMA is a hybrid modulation scheme that combines the low peak-to-average ratio (PAR) of traditional single-carrier formats such as GSM with the multipath resistance and in-channel frequency scheduling flexibility of orthogonal frequency-division multiplexing (OFDM).