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Abstract+A new compact physics-based Alpha-Power Law MOSFET Model is introduced to enable projections of low power circuit performance for future generations of technology by linking the simple mathematical expressions of the original Alpha-Power Law Model with their physical origins. The new model, verified by HSPICE simulations and measured data, includes: 1) a subthreshold region of operation for evaluating the on/off current trade-off that becomes a dominant low power design issue as technology scales, 2) the effects of vertical and lateral high field mobility degradation and velocity saturation, and 3) threshold voltage roll-off. Model projections for MOSFET CVll indicate a 2X-performance opportunity compared to NTRS extrapolations for the 250, 180, and 150nm generations subject to maximum leakage current estimates of the roadmap. NTRS and model calculations converge at the 70nm technology generation, which tixhibits pronounced on/off current interdependence for low power gigascale integration (GSI).

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Faster-than-Nyquist (FTN) signal achieves higher spectral efficiency and capacity compared to Nyquist signal due to its smaller pulse interval or narrower subcarrier spacing. Shannon limit typically defines the upper-limit capacity of Nyquist signal. To the best of our knowledge, the mathematical expression for the capacity limit of FTN non-orthogonal frequency-division multiplexing (NOFDM) signal is first demonstrated in this paper. The mathematical expression shows that FTN NOFDM signal has the potential to achieve a higher capacity limit compared to Nyquist signal. In this paper, we demonstrate the principle of FTN NOFDM by taking fractional cosine transform-based NOFDM (FrCT-NOFDM) for instance. FrCT-NOFDM is first proposed and implemented by both simulation and experiment. When the bandwidth compression factor α is set to 0.8 in FrCT-NOFDM, the subcarrier spacing is equal to 40% of the symbol rate per subcarrier, thus the transmission rate is about 25% faster than Nyquist rate. FTN NOFDM with higher capacity would be promising in the future communication systems, especially in the bandwidth-limited applications.