Patent application number | Description | Published |
20110182383 | Template-based Estimation of Frequency Spectra - Estimating frequency spectrum for digital signals. A frequency spectrum for a digital signal is estimated using a stored template. A frame is received by a receiver on the network. A template is selected from a group of templates based on the received signal parameters, which may include modulation and coding, duration, channel and channel bandwidth, preamble type, beam-forming information, source identifier, and PHY rate. There may be a template for each combination, or a template for a set of related signal types. The template amplitude is scaled based on the signal strength of the received signal to create an estimate of the frequency spectrum, and may also be scaled on duration. The templates may be generated for example to represent IEEE 802.11 transmission modes and rates. Each template represents a frequency spectrum, as an example a FFT spectrum, taken at a specific signal strength. The duration of the frame is later used to calculate the spectrum duty cycle. Spectrum estimation may be performed on the receiver or the device hosting the receiver, with the estimated spectrum sent to a monitoring host, or the signal parameters, strength, and duration may be sent to the monitoring host where spectrum estimation is performed. | 07-28-2011 |
20110188544 | Interference Classification with Minimal or Incomplete Information - Interference classification with minimal or incomplete information. Receivers in access points and in other network devices on a wireless digital network may be switched to a spectrum monitor mode in which they provide amplitude-versus-frequency information for a chosen part of the spectrum. This may be performed by performing a FFT or similar transform on the signals from the receiver. Receivers are calibrated with known interference sources in controlled environments to determine peaks, pulse frequency, bandwidth, and other identifying parameters of the interference source in best and worst case conditions. These calibrated values are used for matching interference signatures. Calibration is also performed using partial signatures collected over a short period in the order of microseconds. These partial signals may be used to detect interferers while scanning. Another aspect of the invention is to record the variation of noise floor in the presence of interference sources. Multiple interference sources may be detected. While data collection is performed in one or more APs, classification may be performed in the | 08-04-2011 |
20110242984 | Displaying a Wideband Spectrum Using a Narrowband Receiver - Methods of aggregating spectrum data captured from a narrowband radio to form a spectrum covering a much wider frequency band. Frequency data, such as FFT spectrum data captured from a narrowband receiver such as an IEEE 802.11 Wi-Fi receiver are combined to display representative real-time FFT, average FFT, and FFT duty cycle data of a wideband spectrum. Data is captured from narrow band radios such as access points, station monitors, or client devices on a wireless network. A wideband spectrum may be aggregated from data captured from one or from multiple devices. Data may be stored for later analysis and display. | 10-06-2011 |
20110243020 | Measuring and Displaying Wireless Network Quality - Methods of calculating and displaying quality metrics on a wireless digital network such as a network using IEEE 802.11 Wi-Fi standards. The quality metric calculation assigns weights only to factors which are observed above a threshold, combining multiple factors into a scalar result. The quality metric is derived from the weighted sum of two or more parameters such as: noise floor offset, channel busy indication, adjacent and overlapping channel interference, interferer duty-cycle, frame retry-rate, PHY error rate and CRC error rate. Quality spectrograms may be used to display calculated quality metrics across a channel, channel range, or frequency band, plotting calculated quality metric versus frequency or channel range over a configurable time frame. Using known locations of radios, quality ranges are mapped onto visual representations such as contour lines, shading density, or color codes, and overlayed for example over floor plans or other site representations. | 10-06-2011 |
20110243021 | Spectrum-aware RF Management and Automatic Conversion of Access Points to Spectrum Monitors and Hybrid Mode Access Points - Methods of operating devices on a wireless network as access points (AP) or spectrum monitors (SM). An adaptive radio management (ARM) process operating on the digital network senses network conditions based on data from APs and SMs on the network, and in response to conditions changes devices from AP operation to SM operation, and from SM operation back to AP operation. A method for providing wideband spectrum analysis functions on a radio operating as an AP on a channel proving client connectivity services. A method for scanning off-channel for shorter durations between transmissions to collect spectral data and a method for explicitly quieting IEEE 802.11 transmissions on a channel to collect spectral data. | 10-06-2011 |
20120008514 | Correlating Data from Multiple Spectrum Monitors - A combination and correlation of data from multiple sensors in a wireless digital network is described. Sensors such as spectrum monitors, access points, and wireless client devices provide spectrum data to one or more central stations connected to the network. Spectrum data from multiple sensors is combined and correlated to provide insight into network operation such as spectrum maps, detection-range maps, and for network diagnostics. Sensors providing spectrum data may be synchronized. Correlating spectrum data from synchronized sensors allows more accurate location of sources such as interferers. The known EIRP of certain wireless devices may be used to improve location estimates, and these devices may be used as calibrations sources for sensors in the wireless network. | 01-12-2012 |
20120119880 | Locating Devices in a Wireless Network - Determining the location of a wireless device to be located (DTL) by three or more locating devices (LDs). LDs operating at known locations estimate the distance to the DTL by sending wireless frames to the DTL and varying frame parameters such as transmit power and data rate, searching for the boundary at which the frame is or is not received and ACKd by the DTL. For a given set of frame parameters, the SNR required to be successfully received at the DTL is known. Given that the configuration of the LD is known, the EIRP of the DL is also known. Estimating the noise floor at the DTL, and using the SNR required to successfully receive the frame at the DTL and the EIRP at the LD transmitting the frame, the path loss can be calculated. From the path loss and operating frequency, a distance estimate is calculated. EIRP of the DTL is not and need not be known. Distance estimates from at least three LDs at known locations allow a location for the DTL to be calculated by a location engine (LE). Distance estimates from more than three LDs allow for an overdetermined solution. Distance estimates derived in this manner may be combined with distance estimates calculated using other approaches, such as measuring signal strengths, or TOA/TDOA measurements. The LE process may reside on a central controller supporting the LDs, on one of the LDs, or on any suitable device with network access. | 05-17-2012 |
20130258889 | Determining Distances Between Wireless Devices - A method includes transmitting frames from a first device to a second device, where a first frame is transmitted at a first value for a particular transmission parameter, and where a second frame is transmitted at a second value for the particular transmission parameter that is different than the first value. For each of the transmitted frames, a determination is made if a corresponding Acknowledgement (ACK) frame, as defined by IEEE 802.11 standards, is received by the first device from the second device. Based on the IEEE 802.11 ACK frames received by the first device from the second device, a distance estimate is calculated from the first device to the second device. | 10-03-2013 |
20140003355 | Method and System to Configure Network Access Points | 01-02-2014 |
20140038651 | Method and System for Using a Minimum Sensitivity Threshold for Receiving Wireless Signals - A method includes computing a minimum sensitivity threshold value for a particular wireless device, configuring the particular wireless device to receive wireless signals with a signal strength higher than the minimum sensitivity threshold value, distributing the minimum sensitivity threshold value to other wireless devices, and configuring the other wireless devices based on the minimum sensitivity threshold value for the particular wireless device. | 02-06-2014 |
20140169432 | INTERFERENCE CLASSIFICATION WITH MINIMAL OR INCOMPLETE INFORMATION - Interference classification with minimal or incomplete information. Receivers in access points and in other network devices on a wireless digital network may be switched to a spectrum monitor mode in which they provide amplitude-versus-frequency information for a chosen part of the spectrum. This may be performed by performing a FFT or similar transform on the signals from the receiver. Receivers are calibrated with known interference sources in controlled environments to determine peaks, pulse frequency, bandwidth, and other identifying parameters of the interference source in best and worst case conditions. These calibrated values are used for matching interference signatures. Calibration is also performed using partial signatures collected over a short period in the order of microseconds. These partial signals may be used to detect interferers while scanning. | 06-19-2014 |