STTR Phase I: Universal Wireless Channel Selection Filter for Enhanced Access to RF Spectrum

This Small Business Technology Transfer (STTR) Phase I project will investigate an ultra-wideband tunable radio frequency filter for use as a universal channel selection filter to maximize spectrum utilization. The research during Phase I will focus on high fidelity modeling of a tunable phase shifter design to provide high linearity, low insertion loss and efficient power utilization. It will also focus on circuit design for continuously tunable cancellation of distortion to fabrication of the circuit in CMOS in a design that will provide linear operation at input high power, independent of signal modulation, coding or channel frequency. The goal is design of a circuit that can be miniaturized for integration in hand held devices of all types to provide continuously tunable reception initially from 700 MHz to 3 GHz, and with a channel bandwidth tunable to 20 MHz and more to support current and pending, as well as legacy, wireless communications standards. The broader impact/commercial potential of this project is it will maximize the carrying capacity of the wireless spectrum, enabling its efficient utilization at frequencies from White Space to WiFi. In addition to benefitting consumer communications, it will also benefit research and technical education, as well as biomedical care by providing continuously tunable RF filters for such instruments. Continuously tunable center frequency will allow smart phones and other software defined radios to use any frequency, by contrast with the limited channel selection provided by the switched filter banks in use today. The distortion cancellation capability will enable linear operation at high input power, such as in receiving OFDM signals from a nearby tower, preventing dropped calls and increasing quality of service. The net result will be to maximize simultaneous users and increase their quality of service while reducing the size, weight and complexity of handheld devices and increasing their reliability, helping the industry meet consumer expectations and aiding continuing growth of wireless industry, which shipped over 500 million smart phones in 2011.