Distributed sphere decoding

Based on a simple gossip algorithm, which computes the sum of values known by several nodes, we investigate the research challenge of distributed sphere decoding. We provide distributed algorithms to perform both the QR decomposition as well as the tree search. Compared to the case where one declares one node as a centralized unit, this approach is much more robust against node and link failures. This is due to the fact that the target nodes for the gossip algorithm are chosen uniformly at random in each iteration. Numerical simulations show that even for a very small number of iterations the results coincide with the traditional centralized sphere decoder.