1. A method for detecting low density signature (LDS) transmissions, the method comprising: receiving, at a receiver of a network component, multiplexing signals based on a plurality of function nodes (FNs); calculating, at a detector of the network component, first values corresponding to OFDM resources at the FNs using first message passing algorithm (MPA) computations over a plurality of variable nodes (VNs) corresponding to symbols of user equipment (UEs) and the FNs, and using a priori information in an initial vector of probabilities for each of the VNs; excluding, from the first MPA computations, first relatively small multiplication terms, wherein the first relatively small multiplication terms include first small exponential terms and first terms with small probabilities; updating the probabilities for the VNs using the calculated first values at the FNs without the excluded first relatively small multiplication terms; and iteratively repeating calculations to update the FNs using second MPA computations, excluding second relatively small multiplication terms and updating second probabilities for the VNs, wherein the second relatively small multiplication terms include second small exponential terms and second terms with small probabilities.