Advanced receiver design boosts performance

摘要

Multiple input/multiple output (MIMO) is the foundational technology underlying all current 4G mobile broadband standards, including WiMax LTE and UMB. To achieve higher throughput and a richer user experience, especially for mobile access to high-bandwidth applications such as YouTube, video gaming and movie downloads, devices must provide optimal reception performance for MIMO signals. MIMO implementations on most current devices, however, offer only suboptimal reception. Using advanced DSP techniques and ASIC technology, the maximum-likelihood decoder (MLD) receiver for spatial multiplexing of the MIMO signal can improve performance. MIMO antenna-processing technology has been adopted by all mobile broadband standards for 4G macrocellular networks, as well as by IEEE 802.1 In for Wireless LANs. By creating multiple parallel, independent data streams among multiple transmit and receive antennas, MIMO increases the transmission rate without increasing the spectrum bandwidth or transmit power. The increase in data rate is proportional to the number of transmit antennas used, and the total transmit power is divided among the antennas. Therefore, if n transmit antennas are used, n independent streams of the data are transmitted, and data throughput is increased n times. The technique is called spatial multiplexing.