Performance evaluation of different signal shaping techniques for the advancing cellular networks

Abstract

Recently, to satisfy the ever-growing data needs, long term evolution (LTE) has been deployed by many operators. LTE enables better spectrum management and avoids the adjacent channel interference by using the orthogonal frequency division multiple access (OFDMA) for downlink and single carrier frequency division multiple access (SC-FDMA) for uplink connection. Even though the spectrum is limited, the number of active devices is increasing which requires the need for extra spectrum. Orthogonal frequency division multiplexing (OFDM) is capable of better quality of service (QoS) as it avoids the multipath fading using equalisation and immune to inter-symbol interference, in addition to its attractive spectral efficiency. However, the LTE system is suffered from peak to average power ratio (PAPR) which reduces the QoS of the communication. Therefore, in this paper, we have proposed a QoS enhancement using a hybridised clipping - selective mapping (Clip-SLM) technique. Different QoS enhancement methods are evaluated for different modulation techniques, phase sequences and number of sub-carriers. From the simulation results, we have shown that the proposed hybridised technique results into significant PAPR reduction which brings substantial bit error rate (BER) reduction and hence QoS enhancement.