A VLSI Architecture of the Square Root Algorithm for V-BLAST Detection



MIMO has been proposed as an extension to 3G and Wireless LANs. As an implementation scheme of MIMO systems, V-BLAST is suitable for the applications with very high data rates. The square root algorithm for V-BLAST detection is attractive to hardware implementations due to its low computational complexity and numerical stability. In this paper, the fixed-point implementation of the square root algorithm is analyzed, and a low complexity VLSI architecture is proposed. The proposed architecture is scalable for various configurations, and implemented for a 4 × 4 QPSK V-BLAST system in a 0.35 \(\mu\)m CMOS technology. The chip core covers 9 \(mm^2\) and 190 K gates. The detection throughput of the chip depends on the received symbol packet length. When the packet length is larger than or equal to 100 bytes, it can achieve a maximal detection throughput of 128 \(\sim\) 160 Mb/s at a maximal clock frequency of 80 MHz. The core power consumption, measured at 2.7 V and room temperature, is about 608 mW for 160 Mb/s data rate at 80 MHz, and 81 mW for 20 Mb/s at 10 MHz. The proposed architecture is shown to meet the requirements for emerging MIMO applications, such as 3G HSDPA and IEEE 802.11n.


VLSI ASIC MIMO BLAST square root algorithm fixed-point CORDIC 3G HSDPA wireless LAN 


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© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  1. 1.Department of ElectroscienceLund UniversityLundSweden

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