Multi-Carrier Waveforms and Multiple Access Strategies in Wireless Networks: Performance, Applications, and Challenges

Abstract

Current generation mobile communications require high-quality services. Adopting multiple access (MA) and multi-carrier waveforms potentially enhances the quality of services offered to end-users. However, in most literature, the integration of multi-carrier and multiple-access approaches have not been extensively examined. One possible solution is to review multiple access and multi-carrier waveforms simultaneously to create a favorable foundation for the integration of these schemes. Thus, we consider a comprehensive review of multiple-access systems and multi-carrier waveforms jointly from 1 st to 5 th -generation (1G-5G) cellular networks. Initially, we present orthogonal MA (OMA) schemes called: frequency division multiple access (FDMA), time division multiple access (TDMA), code division multiple access (CDMA), and orthogonal division multiple access (OFDMA) that have been utilized in 1G, 2G, 3G, and 4G respectively. In addition, 5G wireless non-orthogonal multiple access (NOMA) techniques such as power domain NOMA (PD-NOMA), code domain NOMA (CD-NOMA), and other NOMA multiplexing methods are addressed in detail. On the other hand, we glanced at 5G cellular multi-carrier waveforms such as filter bank multi-carrier (FBMC), universal filtered multi-carrier (UFMC), generalized frequency division multiplexing (GFDM), and filtered orthogonal frequency division multiplexing (f-OFDM) waveforms. The assessment and comparison between different OMA, NOMA, and multi-carrier waveforms are carried out with the parameters: modulation schemes, BER, SNR, sum rate, peak-to-average power ratio (PAPR), latency, out of band emission (OOBE), and complexity. The analytical formulas of OMA, NOMA, and multi-carrier waveform schemes are also derived and verified using simulation data. Each multiple access strategy's merits, shortcomings, applications, and factors influencing its performance are also addressed. Eventually, possible recommendations for the integration of multiple-access and modulation technologies for nextgeneration mobile networks are also included.

Coded Assisted Transmit and Receive IQ Mismatch Compensation With Channel Estimation for AF Cooperative OFDM Systems

“…Let ℜ − → x and ℑ − → x describe the real and imaginary components of vector − → x , − → x = ℜ − → x + jℑ − → x , where ℜ − → x is sent via the I branch and ℑ − → x is broadcast through the Q branch. Bearing this in mind, the modulated signals carried across the I and Q branches are respectively denoted as [21] 2) (3) where − → x (n) is the nth component of vector − → x , f c is the carrier frequency, and T s is the sampling time. Accordingly, the sent radio frequency signal is represented as…”

“…O RTHOGONAL frequency division multiplexing (OFDM) has emerged as the strategy of choice for current and next-generation wireless standards due to its reliability in frequency-selective multipath circumstances and high spectrum efficiency utilization [1], [2]. It has been considered for use in the settings of cellular networks, including the fifth-generation and beyond systems, with its deployment in long term evolution standards [3]- [5]. It has also been effectively deployed in a wide range of other wireless technologies, including local area networks, and radars, microwave, and satellite systems [6]- [8].…”

Performance Analysis of Generalized Frequency Division Multiplexing in Various Pulse-Shaping Filter with Raised Cosine and Root Raised Cosine Filter

“…(5) where α is the roll off factor and T is the transmission symbol period [18]- [20]. The parameters used for the computation of results are given in table…”

Detection of Signals in MC–CDMA Using a Novel Iterative Block Decision Feedback Equalizer

“…The system accommodates  simultaneous users and each user's data bits are first mapped to higher-order signal before it's modulated with unique spreading codes of length N using a mixer. The spreading code of each user are orthogonal to each other and are mutually exclusive [25].…”