Two-Bit SINR Quantization Based Scheduling Scheme for MIMO Communications

In the wireless communication system, the channel experiences losses in the total channel throughput due to some phenomenon like multipath fading, scattering etc. To avoid some of the impairments, basic communication ideas like diversity and multiplexing are used. In the multiple-input and multiple-output (MIMO) system, we are able to experience the advantages of these ideas by using multiple antennas at both the transmitter and receiver side. For the systems where the number of the users is greater than the number of the transmitting antenna, there is need of selecting the best set of receiving antennas among all the antennas. For finding out the best set of receiving antennas the transmitter needs to know about the channel condition. For this there should be some feedback from the users to the base station (BS). Here a scheme for the feedback from the users to the BS is proposed, which tries to optimize the channel throughput of the wireless system with less feedback load. Here, it is shown that the one-bit quantization is not able to achieve spatial multiplexing gain. However, the proposed scheme of quantization with with two bits is able to achieve spatial multiplexing gain. Moreover, the proposed two-bit quantization process achieves better system throughput than one-bit quantization process.