DPFFs:C2MOSDirect Path Flip-Flops for Process-Resilient Ultradynamic Voltage Scaling

We propose two master-slave flip-flops (FFs) that utilize the clocked CMOS (C2MOS) technique with an internal direct connection along the main signal propagation path between the master and slave latches and adopt an adaptive body bias technique to improve circuit robustness.C2MOSstructure improves the setup margin and robustness while providing full compatibility with the standard cell characterization flow. Further, the direct path shortens the logic depth and thus speeds up signal propagation, which can be optimized for less power and smaller area. Measurements from test circuits fabricated in 130 nm technology show that the proposed FF operates down to 60 mV, consuming 24.7 pW while improving the propagation delay, dynamic power, and leakage by 22%, 9%, and 13%, respectively, compared with conventional FFs at the iso-output-load condition. The proposed FFs are integrated into an8×8FIR filter which successfully operates all the way down to 85 mV.

Characterization of Signal Propagation through Limb Joints for Intrabody Communication

Intrabody communication (IBC) is one of the recent physical layers of the IEEE 802.15.6 Wireless Body Area Networks (WBAN) communication standard. It is employed for data transmission in low frequency bands (21 MHz as per standard, 0.3-120 MHz in literature), providing up to 10 Mbps data throughput. An effective way to increase data rate communication is to determine higher operation frequency bands. This paper reports empirical studies which explore signal propagation through the human body including limb joints within the 0.3-200 MHz frequency range. Results show that minimum signal attenuation points occur at 50 MHz and 150 MHz within the range of investigation. The presence of the joint segments along the signal propagation path causes on average 2.0 dB loss (at 50 MHz and 150 MHz), 6.0 dB loss (<1 MHz) and less than 3.0 dB (>150 MHz) compared to limb segments.

Investigations of the lower ionosphere over Antarctica via ELF-VLF radiowaves

The paper discusses ELF-VLF investigations of the low Antarctic ionosphere. Two new methods of lower ionospheric diagnostics are based on an investigation of the VLF electromagnetic field structure in the Earth-ionosphere cavity. One method deals with the analysis of local transverse cavity resonances in the near field of an emitter (a horizontal antenna) with a frequency (~1.5-8 kHz) in the range of the first few resonances. The other method, based on tweek investigations, is applicable under night conditions and enables the characteristics of the low ionosphere to be determined over a signal propagation path. The use of the ELF-VLF transmitter at Siple Station provides a unique opportunity to implement these methods, as does the ELF multipoint recording in the Schumann resonance band of atmospherics excited by powerful lightning discharges.