Ipr Licensing, Inc.

Cognio, Inc.

Cisco Technology, Inc.

Diani Systems, Inc.

Emanate Wireless, Inc.

Chandra Vaidyanathan

Gary L Sugar

Yohannes Tesfai

Neil Robert Diener

Sifen Luo

Matthew Aaron Silverman

Paul Jeffrey Stager

David Stuart Kloper

Hang Jin

Li Guo

Zhigang Gao

Sifen Lou

A wireless room occupancy monitor, system and training method are provided. The room occupancy monitor includes an antenna array configured to detect wireless transmissions from a tag device; a wireless transceiver configured to receive the wireless transmissions detected by the antenna array and produce receive signals; a processor configured to process the receive signals; and a motion sensor coupled to the processor and configured to wake up the processor in response to detecting when the tag device enters or exits a room. The monitor is configured to be mounted proximate an entryway to the room. After the motion sensor wakes up the processor, the processor is configured to power on the wireless transceiver and run an algorithm on a sequence of received signal strength estimates and array response vectors derived from the receive signals to determine when the tag device has entered or exited the room via the entryway.

Wireless room occupancy monitor

A Usage, Condition and Location System (UCLS) tag is provided, which is an active RFID tag that, in addition to location, is configured to determine the usage state and operating condition of a device. The UCLS tag includes sensors that measure physical activity of the associated equipment (vibration, magnetic activity, temperature, etc.). Algorithms may use the information obtained from the UCLS tags to map the measured sensor data to a contextual usage state and operating condition of the device.

Usage, condition and location tag and system

An equal gain composite beamforming technique which includes the constraint that the power of the signal output by each antenna is the same, and is equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. By reducing output power requirements for each power amplifier, the silicon area of the power amplifiers are reduced by as much as N times (where N is equal to the number of transmit antennas) relative to a non-equal gain composite beamforming technique.A method and apparatus are disclosed for a transmission technique by a wireless communications device which includes providing that the power applied to each transmit antenna may be equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. The device may determine a total transmit power and produce a multi-carrier signal for transmission. Accordingly, the device may apply a power to each of the N transmit antennas, for the multicarrier signal, which is equal to the total transmit power divided by N. Further, the device may produce a weight for each of the N transmit antennas used. The device may weight the multi-carrier signal for each antenna per the produced weight. Each transmit antenna signal may be amplified by an amplifier coupled to that antenna.

System and method for antenna diversity using equal power joint maximal ratio combining

An equal gain composite beamforming technique which includes the constraint that the power of the signal output by each antenna is the same, and is equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. By reducing output power requirements for each power amplifier, the silicon area of the power amplifiers are reduced by as much as N times (where N is equal to the number of transmit antennas) relative to a non-equal gain composite beamforming technique.A method and apparatus are disclosed for a multiple input multiple output (MIMO) transmission technique by a wireless communications device which includes providing that the power applied to each transmit antenna may be equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. The device may produce a weight for each of the N transmit antennas used in MIMO transmission. Also, the device may determine a total transmit power and produce a multi-carrier signal for transmission. The device may weight the multi-carrier signal for each antenna per the produced weight. Further, the device may apply a power to each of the N transmit antennas, for the weighted multicarrier signal, which is equal to the total transmit power divided by N. Each transmit antenna signal may be amplified by an amplifier coupled to that antenna.

Two or more data packets transmitted through a wireless channel are received using a receiver device. The two or more data packets are a result of two or more transmissions that are made sequentially in time at different center frequencies in order to span a desired bandwidth. Each data packet of the two or more data packets is transmitted at a single center frequency. Time differences and/or carrier phase differences among the two or more transmissions are estimated. A time-of-arrival of one or more data packets of the two or more data packets is calculated using each data packet of the two or more data packets and one or more of the estimated time differences, the different center frequencies, and the estimated carrier phase differences.

High resolution wireless indoor positioning system for legacy standards-based narrowband mobile radios

An equal gain composite beamforming technique which includes the constraint that the power of the signal output by each antenna is the same, and is equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. By reducing output power requirements for each power amplifier, the silicon area of the power amplifiers are reduced by as much as N times (where N is equal to the number of transmit antennas) relative to a non-equal gain composite beamforming technique.

Multiple-input multiple-output (MIMO) wireless communication techniques are provided that involve mapping multiple spatial streams to corresponding modes of a wireless channel between a plurality of antennas of a first wireless communication device and a plurality of antennas of a second wireless communication device so as to allocate or distribute power unequally to the plurality of modes. In addition, techniques are provided herein to cyclically shift a mapping of spatial streams to modes of the channel.

Power allocation of spatial streams in MIMO wireless communication system

In a positioning system, each network access device in a first subset of N1 network access devices transmits a wireless location beacon signal, producing N1 wireless location beacon signals that are transmitted by the first subset. Each network access device in a second subset of N2 network access devices receives the Ni wireless location beacon signals from the first subset and calculates N1 TOAs from each of the N1 received wireless location beacon signals, producing N1&#xd7;N2 calculated TOAs by the second subset. Using one or more wireless transmissions, one or more network access devices transmits the location coordinates of the network access devices and transmits the N1&#xd7;N2 calculated TOAs, differences calculated among the N1&#xd7;N2 calculated TOAs, or a combination of one or more of the N1&#xd7;N2 calculated TOAs and one or more of the differences calculated among the N1&#xd7;N2 calculated TOAs.

Unsynchronized time-of-flight-based wireless positioning system using network broadcasts

Interference in an unlicensed frequency band is spatially filtered out from received signals at a wireless device operating in the unlicensed frequency band. Energy received at a plurality of antennas of the wireless is device is analyzed to detect interference in the unlicensed frequency band. The detected interference is classified by type. Parameters for a nulling filter are generated or selected based on the type of interference detected in the received energy. During a time interval when it is expected to receive desired signals, the nulling filter is applied using the parameters to signals obtained from energy received at the plurality of antennas during the time interval.

Adaptive interference nulling for MIMO receiver based on interference characteristics

A sequence of two or more signals representing two or more data packets is transmitted through a wireless channel using a transmitter device. The two or more signals are a result of two or more transmissions that are made sequentially in time at different center frequencies in order to span a desired bandwidth. At least one of the two or more signals includes a physical layer preamble. The sequence of two or more signals is received using a receiver device. A time of arrival of one or more signals of the received sequence is calculated using one or more of the received sequence, the time differences among the two or more transmissions, the different center frequencies, information from the two or more data packets, and any carrier phase differences among the two or more transmissions using the receiver device.

System and method for high resolution indoor positioning using a narrowband RF transceiver

In one embodiment a method includes, collecting in-phase/quadrature (I/Q) data representing energy detected by a radio in a frequency band, performing a fast Fourier transform (FFT) on the I/Q data resulting in a stream of FFT blocks, identifying using the stream of FFT blocks a pulse in the frequency band, recording in a radio events record (RER) a plurality of radio events and corresponding timestamps that are indicative, respectively, of a type and time of individual state changes in the radio during the collecting step, and, for example, using at least two of the radio events to identify, in the time domain, a beginning time and end time of the pulse detected in the stream of FFT blocks.

Capturing and using radio events

Systems and methods for sharing an AGC loop between a wireless data demodulator and a spectrum analysis module that operates simultaneously with the data demodulator. In one embodiment, a predetermined hold time prevents the AGC loop from changing gain too often, thereby allowing the spectrum analysis module to collect reliable data. In another embodiment, the hold time may be extended to coincide with a spectrum analysis event, such as a boundary of an FFT block. In still another embodiment, an FFT valid signal is provided such that collected FFT blocks can be designated as suspect and then subsequently processed accordingly.

Sharing AGC loop between demodulator and spectrum analysis system

A radio transmitter and method controls efficiency of each of a plurality of power amplifiers that amplify a corresponding one of a plurality of radio frequency signals for a beamforming transmission by a corresponding one of a plurality of antennas. Each of the plurality of power amplifiers is controlled to operate with one or more operating parameters that optimize the efficiency for an output power level of corresponding ones of the radio frequency signals. Transmit weights for transmit signals are determined and updated on a per-packet basis.

Growing community of inventors

Bethesda, MD, United States of America

Chandra Vaidyanathan