Compressive Millimeter-Wave Sector Selection in Off-the-Shelf IEEE 802.11ad Devices

Achieving data-rates of multiple Gbps in 60 GHz millimeter-wave (mm-wave) communication systems requires efficient beam-steering algorithms. To find the optimal steering direction on IEEE 802.11ad compatible devices, state-of-the-art approaches sweep through all predefined antenna sectors. Recently, much more efficient alternatives, such as compressive path tracking, have been proposed, which scale well even with arrays with thousands of antenna elements. However, such have not yet been integrated into consumer devices. In this work, we adapt compressive path tracking for sector selection in off-the-shelf IEEE 802.1 lad devices. In contrast to existing solutions, our compressive sector selection tolerates the imperfections of low-cost hardware, tracks beam directions in 3D and does not rely on pseudo-random beams. We implement our protocol on a commodity router, the TP-Link Talon AD7200, by modifying the sector sweep algorithm in the IEEE 802.11ad chip's firmware. In particular, we modify the firmware to obtain the signal strength of received frames and to select custom sectors. Using this extension, we precisely measure the device's sector patterns. We then select the best sector based on the measured patterns and sweep only through a subset of probing sectors. Our results demonstrate, that our protocol outperforms the existing sector sweep, increases stability, and speeds up the sector selection by factor 2.3.