By reducing the frequency reuse one can increase substantially the spectral efficiency of cellular systems. On the other hand, complex transmission/detection schemes are required to cope with the inherently high interference. This paper deals with the uplink transmission in cellular systems with universal frequency reuse and SC-FDE (Single-Carrier with Frequency-Domain Equalization) transmission schemes. We consider the use of clustered techniques to simplify the detection procedure and to reduce the side information that must be transmitted by the backhaul network. Our performance results show that we can reduce substantially the signal processing complexity and the required side information without sacrificing the performance.