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One of the topologies that mobile operators have deployed to provide a satisfactory indoor and outdoor coverage is Distributed Antenna Systems (DAS). However, the energy consumed by DAS to meet these coverage and Quality of Service (QoS) requirements contributes to the operational expenses as well as greenhouse gasses emission. This paper looks at how sleep mode can improve the energy efficiency (EE) and spectral efficiency (SE) performance of DAS. Maximal Ratio Transmission (MRT) with perfect Channel State Information (CSI) has been used. The analysis has been further extended to include Fractional Frequency Reuse (FFR). Results have shown that sleep mode improves EE in DAS by 10% and 13% with MRT alone and MRT plus FFR respectively, but reduces SE.