Integrated Photonics Based High Speed Arbitrary Waveform Generation

High speed arbitrary waveform generator enabled by photonic digital to analog converter where the bandwidth limitation arising due to interconnect and device parasitics in its electronic counterparts is circumvented. Leveraging the silicon photonic integration technology for this purpose provides a potential high resolution, high bandwidth, and energy efficient solution for signal transmitters.

Integrated Photonics Based High Speed Arbitrary Waveform Generation

High speed arbitrary waveform generator enabled by photonic digital to analog converter where the bandwidth limitation arising due to interconnect and device parasitics in its electronic counterparts is circumvented. Leveraging the silicon photonic integration technology for this purpose provides a potential high resolution, high bandwidth, and energy efficient solution for signal transmitters.

Science & technology trends in cognitive radar concept

Currently, human operators provide cognition in a radar system. However, advances in the “digitization” of radar front-ends, including digital arbitrary waveform generators (AWG) and advanced high performance embedded computing (HPEC) make it possible to vary all key radar parameters (power, pulse length, number of pulses, pulse repetition frequency (PRF), modulation, frequency, polarization) on a pulse-by-pulse basis within ns or ms and over a wide operating range. This timescale is much faster than the decision-making ability of a human operator. The cognitive-inspired techniques in radar, that are intensively developing last years, mimic elements of human cognition and the use of external knowledge to use the available system resources in an optimal way for the current goal and environment. Radar systems based on the perception-action cycle of cognition that senses the environment, learns relevant information from it about the target and the background and then adapts the radar to optimally satisfy the needs of the mission according to a desired goal are called cognitive radars. In the article, recent ideas and applications of cognitive radars were analyzed.

IC-Based Neuro-Stimulation Environment for Arbitrary Waveform Generation

Electrical stimulation of the nervous system is commonly based on biphasic stimulation waveforms, which limits its relevance for some applications, such as selective stimulation. We propose in this paper a stimulator capable of delivering arbitrary waveforms to electrodes, and suitable for non-conventional stimulation strategies. Such a system enables in vivo stimulation protocols with optimized efficacy or energy efficiency. The designed system comprises a High Voltage CMOS ASIC generating a configurable stimulating current, driven by a digital circuitry implemented on a FPGA. After fabrication, the ASIC and system were characterized and tested; they successfully generated programmable waveforms with a frequential content up to 1.2 MHz and a voltage compliance between [−17.9; +18.3] V. The system is not optimum when compared to single application stimulators, but no embedded stimulator in the literature offers an equivalent bandwidth which allows the wide range of stimulation paradigms, including high-frequency blocking stimulation. We consider that this stimulator will help test unconventional stimulation waveforms and can be used to generate proof-of-concept data before designing implantable and application-dedicated implantable stimulators.