Wisconsin Alumni Research Foundation

University of Michigan

Nec Laboratories America, Inc.

National Science Foundation

Xinyu Zhang

Chi Zhang

Sampath Rangarajan

Mohammad Ali Khojastepour

Karthikeyan Sundaresan

Kang Geun Shin

Jialiang Zhang

Teng Wei

Shilin Zhu

Richard M Laine

Suman Banerjee

Anfu Zhou

Eleni Temeche

Shu Wang

Joshua Tabor

Sanjib Sur

A method of synthesizing a precursor for making a polymer, glass, or ceramic material is provided. The method includes reacting OPClwith NHor MNH, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form O═P(NH2). The method then includes either: (i) reacting the O═P(NH)with M1NH, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor; or (ii) heating the O═P(NH)to form a branched or cyclomeric compound, and reacting the branched or cyclomeric compound with M1NH, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor. The precursor is an oligomer or a polymer. Uses for the precursor and the polymer, glass, or ceramic material as binders, sintering aids, adhesives, and electrolytes in battery components are also provided.

Polymer precursors for solid state electrolytes

A visual privacy system unilaterally blocks rolling shutter cameras by providing a periodically interrupted ambient light source imposing bright and dark bands on the image yet at a frequency imperceptible to human observers in the environment. Communication of the modulation pattern to authorized cameras allows unaffected imaging in these regions by authorized individuals. The system also contemplates operation in a barcoding mode with a light modulation providing embedded barcodes that can be extracted from images taken in the region to indicate that the images were improperly acquired and to block the images in certain applications.

Visual privacy protection system

A system for identifying the location of the mobile device uses standard fluorescent light fixtures commonly found in indoor environments and detects minor variations in the light output of those fixtures caused by normal manufacturing variation. These variations are catalogued as identifying fingerprints together with location of the light fixtures to provide for navigation.

Spatial location indoors using standard fluorescent fixtures

A wireless vibrometer employs an antenna array to significantly boost the signal-to-noise ratio of faint received signals twin small objects vibrating at acoustic frequencies. This technique may be used to provide an improved physiological monitor (such as a pulse detector) or for long-range eavesdropping using the emitted power from a cell phone or the like.

Wireless vibrometer with antenna array

A system for identifying the location of a mobile device uses signatures of standard room lighting derived from the frequency spectrum of light fluctuations associated with driver circuitry of that lighting. Improved sensitivity (frequency and dynamic range) are provided by using a pair of dedicated photodetectors which may deduce a one-dimensional angular location of a light source by comparing the signals developed by two photodetectors having different angular sensitivities.

Navigation system tracking high-efficiency indoor lighting fixtures

A virtual touchscreen for mobile devices provides a touchscreen area displaced to a side of the display to eliminate problems of a finger blocking the display during normal touchscreen operation. The virtual touchscreen may be monitored by a sensor system looking edgewise from a housing of the mobile device employing as few as two displaced photodetectors and a correspondingly oriented light source constrained to sensitivity within a narrow fan-shaped light-sensing plane. Extraction of the spatial location of a finger touch within this touchscreen area may be performed by a model of reflected light signals of a finger in different locations calibrated to environmental parameters of finger reflectivity and background reflectivity by a simple calibration process.

Touch surface for mobile devices using near field light sensing

A visible light communication system identifies the location of a mobile device using light intensities corrected by mobile device orientation. This location can be used to generate a dynamic cluster of visible light transmitters about the mobile device providing improved 'handoff' between transmitters and reduced shadowing.

Location aware communication system using visible light transmission

The inventors have recognized that in RF communication systems, by switching between transmit antennas of an RF transmitter on a sub-symbol basis (antenna index coding), and/or by adaptively determining how often antenna switching occurs (adaptive antenna hopping), an increased amount of data may be wirelessly transmitted to an RF receiver without significantly increasing energy consumption. The inventors have determined that in certain systems, such as ZigBee, data symbols consist of elementary waveform patterns, and that such waveform patterns for transmit antennas may be stored by an RF receiver for later determining transmit antennas for data symbols. The inventors have also determined that the invention may be applied in the frequency domain, such as to OFDM, by storing subcarrier waveform patterns for particular transmit antennas and later determining transmit antennas for subcarriers of data symbols.

Radio frequency communication with antenna index coding

A computer-implemented method is proposed for coordinating communication amongst wireless communication devices in a wireless network. The coordination scheme creates a side channel between heterogeneous wireless devices to enhance their cooperation. At the transmitter, the coordination scheme appends a customized preamble to a data payload, where the preamble is comprised of a sequence of energy pulses separated by a gap and the duration of the gap encodes coordination data for the receive device. At the receiver, the coordination scheme detects the preamble of the data packet; extracts the coordination data from the preamble of the data packet; and coordinates communication between the transmit device and the receive device using the coordination data.

Coordination amongst heterogeneous wireless devices

Systems and methods for system for channel access adaptation are disclosed. One system includes a plurality of remote antennas and a plurality of access points. The remote antennas transmit data to receivers and obtain channel state information. Additionally, each access point controls a different cluster of the remote antennas and receives the respective channel state information from the remote antennas of the cluster. Further, each access point is configured to, independently from other access points, adapt channel allocations to the remote antennas of the respective cluster based on a tracking of sums of collision loss probabilities. Each given sum is determined by the access point for a different given set of a plurality of sets of cooperating remote antennas in the respective cluster, where each constituent collision loss probability in the given sum is determined by the access point from a different interference clique to which the given set belongs.

Scalable network MIMO for wireless networks

In a multiple-input multiple-output (MIMO) wireless system supporting Coordinated Multi-Point (CoMP) transmission and having a first base station, a second base station, and a user equipment, a communications method implemented in the first base station is disclosed. In an aspect, the communications method includes exchanging, with the second base station through local information exchange, first information about a first channel between the first base station and the user equipment and second information about a second channel between the second base station and the user equipment, and computing at least one of a precoding matrix, a receiver filter, and a projection matrix, wherein the user equipment estimates the first information and the second information, and shares the first information and the second information with the first base station. Other apparatuses and some methods for wireless communications also are disclosed.

Coordinated multi-point transmission

Techniques are provided for reducing power consumption in wireless communication devices. During an idle listening period, the clock rate of the receiver in the device is reduced. Data packets received by the receiver are then sampled at the reduced clock rate. A determination is made as to whether the data packet is intended for the device. The clock rate is restored to the full clock rate when the data packet is intended for the device. On the other hand, the receiver continues to operate at the reduced clock rate when the data packet is not intended for the device.

Growing community of inventors

Madison, WI, United States of America

Xinyu Zhang