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An improved and efficient method for static estimation of average and root-mean-squared currents used for electromigration (EM) reliability analysis is presented in this work. Significantly different from state-of-the-art, the proposed method gives closed-form expressions for average and RMS currents in one complete cycle. The proposed method can be readily configured to work with different combinations of ramp and exponential waveforms. Subsequently, the inadequacies of using conventional EM-severity metrics: either the net's lumped capacitance or the net's effective capacitance, along with the regular timing slew, for EM analysis are outlined. As a correction, and, application of proposed method, we provide formulations for deriving the effective "EM" slew, which can be used with conventional approaches to accurately compute the currents. Further, unlike traditional wisdom, we note that not just the RMS current, but even the total charge transfer can depend on the waveform type, and propose formulations to that regard. Additionally, for the first time, we present a method for incorporating the driver's dynamic IR drop while computing RMS currents. Alongside, we lay recommendations for ensuring the standard-cell EM safety at chip level. Finally, we share model-validation results from a production 40 nm design, enabling a 40% higher performance closure.

Determining the geographic location of high frequency (HF) transmitters is of prime importance in both defense and civil operations. In this letter, we present experimental results of distant HF transmitter geolocation performed using the time difference of arrival (TDoA) method. The HF signals considered for our study are transmitted from different locations across Europe. Multiple receivers capable of capturing HF radio signals synchronously are built and a nationwide receiver network with centralized control is deployed in France to assess the feasibility of our approach. HF radio signals are captured simultaneously by all receivers in the network from different European HF broadcast transmitters. From the captured data, the propagation duration differences between the signals received by all receivers are obtained using the cross-channel sounding method. Finally, the transmitter location is estimated using the geolocation algorithm based on the TDoA method. Experimental results demonstrate that it is possible to locate the HF transmitters under favorable conditions with a relative geolocation error ranging from about 0.1 to 10% of the actual ground distance, for most of the experimental scenarios.

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