Prototype of IEEE 802.11af-Based Baseband IC Enabling Compact Device for Wireless Local Area Network Systems in TV White-Spaces

In this paper, we present the world's first prototype of the IEEE 802.11af-based baseband (BB) integrated circuit (IC) enabling compact, low power consumption and even low cost TV white-space (TVWS) devices. Although it has been already over three years since the IEEE 802.11af was standardized in December 2013 as a wireless local area network (WLAN) system utilizing the TVWS, the IEEE 802.11af-based system has not been commercially deployed yet due to difficulties in downsizing, power saving, cost reduction, etc. As well as conventional WLAN systems, an integration of the BB signal processing circuits is one of the promising technologies that can resolve these concerns. The prototype BB IC incorporates IEEE 802.11af physical layer and low-medium access control functions, buffer memories, and interface circuits, thus enabling easy installation, and easy control by connection to a host device via the universal serial bus interface. In addition, we also develop the compact radio frequency (RF) front-end circuit with variable circuits and filters based on the direct conversion scheme by using an off-the-shelf RF IC. By incorporating the prototype BB IC and the RF front-end circuit, we successfully prototype compact card-type TVWS devices in all-in-one package including an antenna. The practicality of the prototype BB IC is demonstrated by characterizing the card-type TVWS devices in respect to transmission and reception performance and throughput.