With explosive growth of Internet access from smart phones and tablets, increasing bandwidth for WIFI system is badly needed. Depending on two years’ research, we produced a novel communication system called WIFO system, which integrates both RF (Radio Frequency) and FSO (Free Space Optical) techniques. WIFO system can significantly increase...
We present a theoretical free-space optical (FSO) transmitter that utilizes a dynamically steered and shaped laser beam to communicate with a randomly moving receiver adorned with a retroreflector. The transmitter tracks the receiver's position by repeatedly scanning the field of view (FOV), measuring reflections from the retroreflector, and estimating the...
For mmWave Integrated Circuit (IC) design, co-integration of passives can reduce size and power consumption, increase reliability, and reduce overall cost. However, skin and proximity effects in the metallization are aggravated at mmWave frequencies, resulting in increased attenuation and degradation of overall performance. Furthermore, tight integration of passive components (to...
This work presents an inductor less switched capacitor based energy harvester, which can simultaneously harvest from 2 energy sources (Solar + Piezo). The proposed harvester employs 2D maximum power point tracking algorithm, by changing the conversion ratios of the charge pumps for piezo and solar sources, and 1D voltage regulation...
Continuous-time ΔΣ modulators are widely used in cellular handsets due to their power efficiency and inherent anti-aliasing characteristics. To achieve demanding cellular bandwidth requirements while maintaining good power efficiency, multi-bit feedback is typically used. This approach provides benefits such as lower OSR, relaxed loop filter requirements, and reduced jitter sensitivity....
The rapid scaling of network bandwidth and data center throughput has motivated the wide adoption of high speed transceivers. Silicon photonics (Si-Photonic) is one of the most promising techniques to realize tightly integrated optical transceivers for next-generation high speed I O standards. This dissertation focuses on the design techniques of...
The design of mobile wireless devices has always focused on reducing power, area, and cost. This dissertation proposes two techniques that are leveraged to save power and area and therefore cost. The first techniques reduces the noise in the receiver and results in a relaxed power requirement. The second technique...
For today’s ubiquitous portable devices, innovative integrated circuits with high performance
yet very low power are necessary. As these devices are used to communicate and sense real world signals in the environment, analog-to-digital converters (ADC) and systems are the key interface circuits needed to digitize the sensed information and they...
Modern sensor network applications are often implemented wirelessly in order to lessen installation costs and reduce deployment times. Unfortunately, these wireless sensor network (WSN) nodes must often rely on batteries or energy harvesting techniques in order to sustain their operation and supply the power needed to maintain communication within the...
Incremental ADCs (IADCs) have found wide applications in sensor interface circuitry since, compared to ∆Σ ADCs, they provide low-latency high-accuracy conversion and easy multiplexing among multiple channels. On the other hand, continuous-time ∆Σ ADCs (CTDSM) have been receiving more and more attention as a power-efficient solution in targeting medium to...