Research of Sphere Decoding Detection Algorithm in LTE-A System

Multi-Input Multi-Output (MIMO) has become a popular technique to increase spectral efficient. Meanwhile, the design of cost-effective receiver for LTE-A system remains a challenging task. The sphere detection algorithm performs exact Maximum Likelihood (ML) detection algorithm, however, its decoding complexity is greatly impacted by the initial radius of decoding. A new type of sphere decoding algorithm based on threshold is proposed in this paper. This new algorithm, considering the influence of signal-to-noise ratio and channel condition number on detection algorithm, has lower sphere decoding complexity and ensures performance of sphere decoding. This algorithm has been applied to the LTE-TDD wireless integrated test instrument and has shown perfect performance.