  This paper presents a physical model for Single Carrier-Frequency Division
Mutliple Access (SC-FDMA). We specifically show that by using mutlirate signal
processing we derive a general time domain description of Localised SC-FDMA
systems relying on circular convolution. This general model has the advantage
of encompassing different implementations with flexible rates as well as
additional frequency precoding such as spectral shaping. Based on this
time-domain model, we study the Power Spectral Density (PSD) and the Signal to
Interference and Noise Ratio (SINR). Different implementations of SC-FDMA are
investigated and analytical expressions of both PSD and SINR compared to
simulations results.
