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Flippo The Robo-Shoe-Fly: A Foot Dwelling Social Wearable Companion

Social interactions in school and office settings traditionally involve few coordinated physical interactions, and most group engagement centers on sharing electronic screens. Wearable robot companions are a promising new direction for encouraging coordinated physical movement and social interaction in group settings. A UC Santa Cruz researcher has developed a wearable social companion that encourages users to interact via physical movement.

A Novel Iot Protocol Architecture; Efficiency Through Data And Functionality Sharing Across Layers

The Internet’s TCP/IP protocol architecture is a layered system design. As such, the functions performed by the TCP/IP protocol suite are implemented at different protocol layers, where each layer provides a specific set of services to the layer above through a well-defined interface. Using this interface, data being received or sent is passed up or down the stack on its way through the network.However, layered design approaches can increase overhead, as each layer incurs additional communication (e.g., additional header field) and processing costs. Furthermore, limiting the flow between layers to data plane information restricts the sharing of control information across layers and may lead to functions being duplicated at different layers. 

Noise Reduction In High Frequency Amplifiers Using Transmission Lines To Provide Feedback

Low noise amplifiers are ubiquitous in wireless data network receivers and radios. Themaximum transmission distance is limited by the receiver noise which is mostly determined by the noise figure of the first amplifier stage, the LNA. Reduction of LNA noise is thus always desirable in that it can increase transmission range or reduce power consumption resulting in higher performance or reduced system cost. This approach lowers the noise of the LNA relative to the other available methods.

Carrier Sense Multiple Access With Collision Avoidance And Pilots (CSMA/CAP)

The traditional collision avoidance handshake consists of a request-to-send (RTS), clear-to-send (CTS), a data packet, and an acknowledgment (ACK). However, this system can result in multiple access interference on variable-length data packets and acknowledgements. This can even occur in multi-hop wireless networks when hidden terminals, exposed transmitters, or exposed receivers are present. 

(SD2021-331) SyncScatter: Enabling WiFi like synchronization & range for WiFi backscatter communication

WiFi backscattering can enable direct connectivity of IoT devices with commodity WiFi hardware at low power. However, most existing work in this area has overlooked the importance of synchronization and, as a result, accepted either limited range between the transmitter and the IoT device, reduced throughput via bit repetition, or both.

(SD2021-267) Improving the Range of WiFi Backscatter Via a Passive Retro-Reflective Single-Side-Band-Modulating MIMO Array

Wi-Fi is the most ubiquitous wireless networking technology for loT in homes, offices, and businesses. Since the power of Wi-Fi transceivers (10s-to-100s of mW) can be prohibitively high for emerging classes of loT devices (which desire <100μW), recent work has suggested piggybacking baseband signals from the loT device directly on top of incident Wi-Fi signals generated by access points (APs) via Wi-Fi-compatible backscatter modulation, where as low as 28μW of active power has been demonstrated. However, the major limitation of this approach is range.

(SD2019-199) ULoc: Robust, Scalable and cm-Accurate UWB Tag Localization

A myriad of IoT applications, ranging from tracking assets in hospitals, logistics, and construction industries to indoor tracking in large indoor spaces, demand centimeter-accurate localization that is robust to blockages from hands, furniture, or other occlusions in the environment. With this need, in the recent past, Ultra Wide Band (UWB) based localization and tracking has become popular. Its popularity is driven by its proposed high bandwidth and protocol specifically designed for localization of specialized "tags". This high bandwidth of UWB provides a fine resolution of the time-of-travel of the signal that can be translated to the location of the tag with centimeter-grade accuracy in a controlled environment. Unfortunately, we find that high latency and high-power consumption of these time-of-travel methods are the major culprits which prevent such a system from deploying multiple tags in the environment. Since UWB has been developed as localization specific protocol, there has been a need for infrastructure based, low-power and real-time indoor localization while providing cm-Accurate 3D UWB tag locations. The UCSD researchers have solved these limitations by novel hardware, firmware and algorithm designs. 

(SD2020-249) Adaptive Bias Circuits For CMOS Millimeter-Wave Power Amplifiers: state-of-the-art back-off efficiency for silicon Ka-band Doherty PAs using single inputs and without digital predistortion

Power amplifier performance for emerging 5G mm-wave systems poses significant challenges for output power, efficiency and linearity. Efficiency in backoff is a key concern, given the peak-to-average power ratio of order 6-9dB for 5G signals. As a result, considerable attention has been given to composite amplifiers featuring backoff efficiency enhancement, particularly Doherty amplifiers. Adaptive bias circuits have been previously developed for use with power amplifiers at low microwave frequencies (for example, 1-2GHz as applied in 2G, 3G and 4G cellular networks).  Direct application of these techniques is not straightforward at higher frequencies, such as 28GHz as used for 5G wireless communications, because the transistors have less gain at the high frequencies. 

Magneto-Optic Modulator

Brief description not available

(SD2018-032) Intrinsically Linear Transistor for Millimeter-Wave Low Noise Amplifiers

There has been a steady rise in interest in utilizing Fin high-electron mobility transistors HEMT devices to reduce the source access resistance and enhance the linearity but this linearity is not accessible at gate voltages beyond those at which the gate Schottky diode turns on (~2 V). All known transistor technologies are intrinsically non-linear. This non-linearity leads to signal distortion and power loss. Non-linearity is embodied in a decrease of the transistor current gain cut-off frequency, fT, and maximum oscillation frequency, fmax, with an increase in the drain current.  In contrast, the patented technology here is one of a new Fin MOS-HEMT device permits flexible engineering of the device threshold voltage in order to attain linearity over a wider VGS range (voltage between transistor gate and source (VGS) in excess of the threshold voltage (Vt) where Vt is defined as the minimum).

(SD2021-225) Wireless Contact Force Sensing and Localization

Our sense of touch is critical for understanding and interacting with the world around us. While interacting with the physical world, force-sensitive mechanoreceptors in the skin respond to various vibrations, motions, pressures, and stretching of the skin to provide us with critical information on the location and magnitude of the stimuli. Thus, if we want the next generation of tactile sensors to emulate how our skin reacts to stimuli, we need to both sense the magnitude and location of contact forces acting on the sensing surface.Contact force is a natural way for humans to interact with the physical world around us. However, most of our interactions with the digital world are largely based on a simple binary sense of touch (contact or no contact). Similarly, when interacting with robots to perform complex tasks, such as surgery, we need to acquire the rich force information and contact location, to aid in the task.

Compressive High-Speed Optical Transceiver

Researchers at the University of California, Davis have developed an optical transceiver that uses compressive sensing to reduce bandwidth requirements and improve signal resolution.

Adapting Existing Computer Networks to a Quantum-Based Internet Future

Researchers at the University of California, Davis have developed an approach for integrating quantum computers into the existing internet backbone.

(SD2019-307) Autonomous Millimeter Accurate Mapping of WiFi Infrastructure AND Reverse Localization of COTS WiFi Access Points

Indoor localization has been studied for nearly two decades fueled by wide interest in indoor navigation, achieving the necessary decimeter-level accuracy. However, there are no real-world deployments of WiFi-based user localization algorithms, primarily because these algorithms are infrastructure dependent and therefore assume the location of the Access Points, their antenna geometries, and deployment orientations in the physical map. In the real world, such detailed knowledge of the location attributes of the access point is seldom available, thereby making WiFi localization hard to deploy.   Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0in; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Location services, fundamentally, rely on two components: a mapping system and a positioning system. The mapping system provides context, and the positioning system identifies the position within the map. Outdoor location services have thrived over the last couple of decades because of wellestablished platforms for both these components (e.g. Google Maps for mapping, and GPS for positioning). In contrast, indoor location services haven’t caught up because of the lack of reliable mapping and positioning frameworks (and lack of integration between the two). SLAM methods construct maps that aren’t tagged with locations. Wi-Fi positioning lacks maps, and is also prone to environmental errors. In contrast, indoor navigation even with significant interest from industry and academia lacks further behind.  We cannot use our smartphone to navigate to a conference room in a new building or to find a product of interest in a shopping mall. The primary reason for the poor indoor navigation system is the unavailability of indoor localization augmented maps and floor plans. On one hand, Google and a few other providers make indoor floor plans for airports, malls, and famous buildings, those floor-plans have to be created manually and often need to updated as floor plans change and they lack details such as the position of furniture and other obstacles. On the other hand, besides mapping, ability to position users’ location on these indoor maps is necessary for indoor navigation  

High-Frequency Imaging and Data Transmission Using a Re-configurable Array Source with Directive Beam Steering

Researchers at the University of California, Davis have developed a reconfigurable radiator array that produces a high frequency directed beam via uninterrupted, scalable, electronic beam steering.

(SD2020-464) Enabling Reliable Mmwave Link Using Multi-Beam Pro-Active Tracking

Millimeter-wave communication with high throughput and high reliability is poised to be a gamechanger for V2X and VR applications. However, mmWave links are notorious for low reliability since they suffer from frequent outages due to blockage and user mobility. Traditional mmWave systems are hardly reliable for two reasons. First, they create a highly directional link that acts as a single point of failure and cannot be sustained for high user mobility. Second, they follow a `reactive' approach, which reacts after the link has already suffered an outage. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0in; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

Phased-Locked Loop Coupled Array for Phased Array Applications

Researchers at the University of California, Davis have developed a phased-locked loop coupled array system capable of generating phase shifts in phased array antenna systems - while minimizing signal losses.

Systems and Methods for Sound-Enhanced Meeting Platforms

Computer-based, internet-connected, audio/video meeting platforms have become pervasive worldwide, especially since the 2020 emergence of the COVID-19 pandemic lockdown. These meeting platforms include Cisco Webex, Google Meet, GoTo, Microsoft Teams, and Zoom. However, those popular platforms are optimized for meetings in which all the participants are attending the meeting online, individually. Accordingly, those platforms have shortcomings when used for hybrid meetings in which some participants are attending together in-person and others attending online. Also, the existing platforms are problematic for large meetings in big rooms (e.g. classrooms) in which most or all of the participants are in-person. To address those suboptimal meet platform situations, researchers at UC Berkeley conceived systems, methods, algorithms and other software for a meeting platform that's optimized for hybrid meetings and large in-person meetings. The Berkeley meeting platform offers a user experience that's familiar to users of the conventional meeting platforms. Also, the Berkeley platform doesn't require any specialized participant hardware or specialized physical room infrastructure (beyond standard internet connectivity).

Carbon Nanotube based Variable Frequency Patch-Antenna

Researchers at UCI have developed a patch antenna constructed from carbon nanotubes, whose transmission frequency can be tuned entirely electronically. Additionally, the antenna can be made operable in the microwave to visible frequency regime by simply varying the device dimensions and composition.

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