Lattice Decoding Using Accelerated Sphere Decoder

Sphere decoding algorithm (SDA) is a computationally efficient way for maximum likelihood detection in various lattice decoding problems. The main unsolved problem in SDA is initial radius selection. In this paper a new accelerated version of Viterbo-Boutros SDA is devised in which large initial radius selection, does not sacrifice the decoding speed of sphere decoder. In the new proposed method, lattice structure is incorporated in sphere decoding to accelerate the radius reduction in some dimensions faster than the others.