{'fraction_non_alphanumeric': 0.025442477876106196, 'fraction_numerical': 0.0, 'mean_word_length': 5.114864864864865, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Design of A Low-Complexity Receiver for Uplink SCMA with Multiple Receive Antennas

Sparse Code Multiple Access (SCMA) has been proposed as a potential scheme to increase the spectral efficiency in overloaded scenarios. Most SCMA receivers are based on the Message-Passing Algorithm (MPA) because of the intrinsic graph structure of the resource allocation. In this paper, we discuss two low-complexity receivers that reduce the MPA complexity order. The first is a threshold-based edge-selection, which is an extension of results from a previous work to systems with multiple receive antennas. The second is a selection of receive antennas that minimizes the signal-to-interference ratio of the observed signal during the MPA calculations. Numerical simulation results show that each technique has its own advantages depending on the system parameters and signal-to-noise ratio (SNR) range of operation.