Abstract
The main challenge in any high-speed digital communication system is how to maximize the data rate with minimizing the bit error rate. Several techniques have been developed to achieve this point. Some of these techniques are orthogonal frequency division multiplexing (OFDM), single-carrier frequency domain equalization (SC-FDE), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA). These four techniques are described briefly in this paper. Also, the paper measures the performances of OFDMA and SC-FDMA systems over international telecommunication union (ITU) vehicular-A channel using minimum mean square error (MMSE) equalization. Simulation results show that the performances with interleaved mapping outperform that with localized mapping. Also, the performances with quadrature phase shift keying(QPSK) are better than that with 16-ary quadrature amplitude modulation (16QAM). In addition, the performance of SC-FDMA is better than that of OFDMA, when QPSK is used, but the latter is little bit better than that of SC-FDMA when 16QAM is used
Highlights
Multi-carrier transmission techniques are used in modern wireless mobile systems to provide virtually error-free high bit rates
If these data streams belong to different terminals or users, orthogonal frequency division multiplexing (OFDM) becomes orthogonal frequency division multiple access (OFDMA) [3–6] in which different data signals are transmitted through a common physical media that is divided into frequency resources units
Both OFDM and OFDMA suffer from power distortion that may be troublesome in uplink transmissions where excessive complexity in user terminal is an issue
Summary
Multi-carrier transmission techniques are used in modern wireless mobile systems to provide virtually error-free high bit rates. The most prominent example of MCM transmission is orthogonal frequency division multiplexing (OFDM) [1,2,3] In this technique, a large number of orthogonal sub-carriers are used to transmit information from several parallel streams modulated with a digital modulation scheme. A large number of orthogonal sub-carriers are used to transmit information from several parallel streams modulated with a digital modulation scheme If these data streams belong to different terminals or users, OFDM becomes orthogonal frequency division multiple access (OFDMA) [3–6] in which different data signals are transmitted through a common physical media that is divided into frequency resources units. The SC-FDE is based on OFDM but uses only a single carrier
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
