Spectral Efficiency Comparison of OFDM and MC-CDMA with Carrier Frequency Offset

Abstract

Inter-carrier interference and multiple access interference due to carrier frequency offset (CFO) are two major factors that deteriorate the performance of orthogonal frequency division multiple access (OFDMA) and multicarrier code division multiple access (MC-CDMA) in wireless communication. This paper presents a new mathematical analysis for spectral efficiency of OFDMA communication systems over a frequency selective Rayleigh fading environment in the presence of multiple users. It also compares the spectral efficiency performance of OFDMA and MC-CDMA at different load, signal-to-noise ratio, CFO and delay spread conditions. MC-CDMA is found to be more resilient to CFO in general, however, OFDMA performs better at high load.

Keywords

• OFDM
• MC-CDMA
• spectral efficiency
• carrier frequency offset
• inter-carrier interference
• multiple access interference