Performance Evaluation of Non-orthogonal Multiple Access in V2V communications Over Double-Rayleigh Fading Channels

Rate Compatible Modulation for Non-Orthogonal Multiple Access

“…For example, consider a 2-user RCM-MAC system, where users 1 and 2 transmit their source blocks u 1 and u 2 utilizing encoding matrices G (1) and G (2) , respectively. Assume the following design multi-sets W…”

“…When perfect Channel State Information (CSI) is available at the receiver in point-to-point communications, the fading complex gain h j of coded symbol j is canceled by multiplying the received sample by hj |hj | 2 , where h j denotes the conjugate of h j . Decoding is performed by incorporating the scaling factor 1 |hj | 2 to the noise variance of symbol j in the factor graph. However, in the multi-user scenario this is not possible, since the received symbols are combinations of several coded symbols, each with its own fading factor {h…”

“…On the other hand, when the Rayleigh fast fading MAC is considered, the presence of different fading factors multiplying the weights connecting the users makes EXIT curves depend on the number of users and their rate splits. Thus, when obtaining the conditional PDF of the extrinsic LLR message at the Check Node (CN) decoder by Monte Carlo simulation, one has to take into account the fading factors [h (1) , h (2) , . .…”

“…In contrast, in a Non-Orthogonal Multiple Access (NOMA) all users share the same frequency and time intervals for their transmissions. NOMA systems outperform OMA schemes in multiple scenarios, such as downlink systems [1], visible light communication systems [2] and short packet communications [3]. Thus, NOMA plays an important role in 5G [4,5,6] and is one of the key technologies that will enable the upcoming 6G networks [7].…”

Performance of downlink NOMA‐enabled vehicular communications over double Rayleigh fading channels

“…Moreover, the literature related to the investigation of NOMA‐enabled vehicular communications is sparse. Recently, the authors in [52] have analysed the outage and throughput performances of downlink power‐domain NOMA in V2V communications over double‐Rayleigh fading.…”