Packet delayed lattice reduction algorithm for high performance MIMO decoder

We propose a packet delayed lattice reduction aided MIMO detection for 802.11n system. Lattice reduction algorithms are iterative in nature that results in long latency. In high throughput systems like 802.11n, reduction of latency via parallelization causes high hardware complexity. Without parallelization, the receiver needs to buffer the incoming data until the lattice reduction finishes. Depending on the latency of the lattice reduction, this buffering may cause deep memory requirements as well as missed interframe space deadline requirement. In this paper, we resolve this problem by foregoing buffering of incoming data for the current packet and use the output of lattice reduction to the next packet after the computation is finished. We show that lattice aided MIMO detection can be delayed for as much as 15ms with negligible effect on performance.