Research of Improved Sphere Decoding Algorithm

Multiple-Input Multiple-Output (MIMO) sets up multiple antennas at the transmitting and receiving terminals respectively and makes full use of the space characteristic of the channel, and realizes the transmission and reception of the multiple data streams in the same frequency band and the same time. And MIMO is one of the key technologies in the new generation wireless mobile communication system. This paper firstly analyzes the sphere decoding algorithm which is widely studied in the MIMO system in recent years, and the two traditional algorithm of the sphere decoding algorithm are researched, VB algorithm and CL algorithm. Then an improved sphere decoding algorithm based on the CL algorithm id proposed. The improved sphere decoding algorithm firstly rearranges the channel matrix, and then the idea of radius iteration is introduced, which establishes a new radius updating formula in order to reduce the computing complexity of the algorithm. The simulation experiments show that compared with the traditional sphere decoding algorithm, the improved sphere decoding algorithm reduces the complexity without causing significant performance losses.