Spectrum sensing finds its use is many applications. With modern communication systems moving towards Cognitive Radios (CRs) to better utilize the available spectrum, spectrum sensing is a key enabling functionality that allows the detection of primary users and interferes to support spectrum sharing. Spectrum sensing can also be useful in security applications that require a certain degree of RF spectrum awareness. In addition, it can be used for built-in self-test like transmitter tuning by measuring the output spectrum to allow spur reduction and digital predistortion.
To be useful, the spectrum scanners used for sensing should be able to handle large blockers and detect weak signals at the same time. Thus both good linearity and high sensitivity are desired. In addition, these scanners need to be highly programmable and selective while incurring a low power cost. In this research, we have addressed the issues that plague traditional spectrum scanners by using the recent technique of Filtering by Aliasing (FA). The FA-based spectrum scanner is a passive structure that uses simple but linear, periodically time-varying (LPTV) R-C circuits. This LPTV circuit is shown to provide a high spurious-free dynamic range precise resolution bandwidths while still consuming very low power.
In this talk, I will briefly explain the FA technique, the design considerations and implementation of a spectrum scanner IC that achieves excellent linearity and low power as compared to state-of-the-art designs. In addition, a theoretical analysis of some of the limiting factors of the design will be presented together with some circuit and/or signal-processing solutions.
Biography:
Neha Sinha received her Bachelor’s in Applied Science in Electrical Engineering (Honors, Co-op) from University of Waterloo, Canada in 2010 and Master of Science from UCLA in 2012. She is currently working towards her doctoral degree at UCLA. She has worked as an engineering intern at Kapik Integration, Sun Microsystems, and ON Semiconductor among others. She is also a recipient of the NSERC Postgraduate Scholarship during her Masters and PhD program from the Government of Canada. Her research interests are in the area of mixed-signal circuit design and application of signal processing techniques for circuit enhancements