The present invention relates to a Multiple Input Multiple Output wireless system, and especially to a selecting apparatus for receiving antennas of a Multiple Input Multiple Output wireless system and a method thereof.
For higher transmission speed and larger transmission range, Multiple Input Multiple Output (MIMO) system is used. By using multiple transmit and receive antennas, space multiplexing offers several subchannels for data transmittance. Thus, MIMO system allows each of the independent signal streams being modulated and transmitted through a different antenna at the same time. Although several antennas are used as multiple receiving pathways to increase accuracy of signal detection, only a limited number of integral receiving pathway is allowed in practice if considering power consumption and hardware complexity. When only a signal stream is transmitted at one time, the receiving antenna with the highest signal energy is selected as the signal-receiving source for signal detection. When several signal streams are sent at the same time, the above-mentioned method will no longer work. Methods and apparatuses with higher power consumption or more complicated design will be needed to finish the task of the signal detection. For example, such as those involving computation of determinants that run in the frequency domain.
Thus, there is a need to provide a new selecting apparatus for receiving antennas of the Multiple Input Multiple Output System and a method thereof that not only overcome shortcomings of conventional receiving antennas but also simplifies complicated design of hardware.