Abstract: Implementations of the technology described herein provide adjustment to the time-of-departure (ToD) of the start of the acknowledgement frames (ACK) based on the time-of-arrival (ToA) estimation and correction of their corresponding message frames to keep the turnaround time of the acknowledgement frames stable to a predefined order of precision, with special applications for Wi-Fi ranging to achieve double-sided time-of-arrival (ToA) correction accuracy with minimal frame exchanges. A receiving station uses its time-of-arrival (ToA) correction to adjust the transmission time of an acknowledgement message (ACK) so that both the sending station and the receiving station can estimate round trip time (RTT) (or perform ranging) at the same level or higher accuracy.

Abstract: Systems, apparatus and methods for determining a cyclic shift diversity (CSD) mode are presented. Examples use two different autocorrelations to determine a current CSD mode. Specifically, a delay-based autocorrelation and a cyclic shift-based autocorrelation are each computed then compared to each other, for example, by taking a difference of the two autocorrelations. A multipath signal leads to similar autocorrelations, where as a signal with a CSD mode enabled leads to dissimilar autocorrelations. By examining the number of peaks in the delay-based autocorrelation or the autocorrelation difference, a current CSD mode may be determined.

Abstract: A system and method are disclosed for performing ranging operations between two wireless devices without employing cyclic shift diversity (CSD) compensation techniques. For some embodiments, a first wireless device sends a negotiation request frame requesting the second wireless device to respond to subsequently received frames of a specified type using a selected one of the transmit chains in the second wireless device. Thereafter, the first wireless device sends a data frame to the second wireless device to initiate a ranging operation. The second wireless device sends a response frame of the specified type to the first wireless device using the selected one of the transmit chains.

Abstract: Disclosed are systems, methods and devices for obtaining round trip time measurements for use in location based services. In particular implementations, a fine timing measurement request message wirelessly transmitted by a first transceiver device to a second transceiver device may permit additional processing features in computing or applying a signal round trip time measurement. Such a signal round trip time measurement may be used in positioning operations.

Abstract: Disclosed are systems, methods and devices for obtaining round trip time measurements for use in location based services. In particular implementations, a fine timing measurement request message wirelessly transmitted by a first transceiver device to a second transceiver device may permit additional processing features in computing or applying a signal round trip time measurement. Such a signal round trip time measurement may be used in positioning operations.

Abstract: This disclosure includes systems and methods for determining the location of each of a plurality of STAs of a WLAN where an AP measures the round-trip time (RTT) and the angle of arrival (AOA) to each STA from implicit packet exchange, such as data frame and ACK frame. The AP may then report the RTT and AOA measurements to each STA using a dedicated beacon information element (IE) which multicasts RTT and AOA measurements to the STAs. By employing an additional parameter, namely, angle of arrival AOA, a single AP may compute the two-dimensional location of each associated STA. Further, another beacon IE may multicast mapping of the AIDs to MAC addresses so that the associated STAs can understand such mapping for STAs in a network so that one STA may know the location of other STAs. Encryption may be employed to achieve privacy.

Abstract: Methods, systems, and devices are described for a wireless positioning framework in which an access point (AP) broadcasts a message within a beacon interval that identifies a transmission schedule for a set of stations. The message may include an information element identifying the stations in the set. The set may be determined based on station clock drifts and/or a ranging accuracy sought by the AP. The AP may also provide a station identifier, and frame spacing and delay parameters, which may be used to determine a distinct backoff for each station. Using distinct backoffs allow the stations to avoid collisions when sending the transmissions. The AP may receive the transmissions according to the identified schedule and may determine a range (e.g., round-trip time) for each station in the set based at least on a time at which the respective transmission is received.

Abstract: The present invention discloses a pressure point inspection device, able to press on a plurality of pressure points on liquid crystal display panel for inspecting display condition, the pressure point inspection device includes: lateral adjustment board, lateral adjustment board including a first lateral board and a second lateral board; vertical adjustment board, disposed crossly on lateral adjustment board, vertical adjustment board including first vertical board and second vertical board, able to fold separately; wherein lateral adjustment board and/or vertical adjustment board disposed with a plurality of inspection heads, vertical disposition gap between first lateral board and second lateral board adjustable and lateral disposition gap between first vertical board and second vertical board adjustable. As such, the pressure point inspection device can save time of pressing pressure points on TFT-LCD and improve inspection efficiency and avoid missing pressure point.

Abstract: A method and apparatus for broadcasting short interframe space information to aid in determining a round trip time are provided. The round trip time is used as an aid in locating nodes within a WiFi or WLAN network. The method begins with capturing a time of transmission of a frame by a transmitting station. The receiving station then captures the time of arrival of the frame just sent by the transmitting station. The receiving station replies with a received frame message and the time of departure is captured. The transmitting station then captures the time of arrival of the received frame message. The captured arrival and departure times of the frame and the received frame message allow the round trip time to be computed. The RTT may then be included as part of a network message.

Abstract: A system and method are disclosed for performing ranging operations (700) between two or more wireless devices (STA1 and STA2). For some embodiments, the ranging operation allows each of a pair of ranging devices to estimate timing errors associated with measuring the time of arrival (TOA) of received signals, and to remove such timing errors from the measured TOA values. TOA and time of departure (TOD) information may also be exchanged between the devices using measurement action frames defined by IEEE 802.11v standards. In addition, an iterative process (800) is disclosed that allows a sequence of measurement action frames exchanged between the ranging devices to refine the timing errors and thus also refine the round trip time (RTT) value of signals exchanged between the devices.

Abstract: A hybrid positioning system can be implemented to improve location estimation of a wireless network device when reference network devices can have different distance calibration constants. For each of a plurality of positions at which the wireless network device is placed and for each reference network device, a distance between the wireless network device and the reference network device is determined. A first positioning algorithm is executed to determine an intermediate location (corresponding to each position) of the wireless network device and a distance calibration constant for each reference network device based, in part, on a corresponding initial location of the wireless network device. A second positioning algorithm is executed to estimate a subset of the positions of the wireless network device based on the intermediate location (corresponding to the position) of the wireless network device and the distance calibration constant of each of reference network devices.

Abstract: A TOA positioning system can be implemented that employs a calculated initial location of a wireless network device. For each of a plurality of reference wireless network devices, a distance between the wireless network device and the reference wireless network device is determined based, at least in part, on a round trip transit time between the wireless network device and the reference wireless network device. An initial location of the wireless network device can be calculated based, at least in part, on a location of each of the plurality of reference wireless network devices. A location of the wireless network device can be estimated based, at least in part, on the calculated initial location, the distance to each of the reference wireless network devices, and an initial distance calibration constant.

Abstract: A concatenated coded modulation communication system and method combines Trellis Coded Modulation with non-Gray code constellation mapping, interleaving, and non-binary Low Density Parity Check coded channel modulation with Gray code constellation mapping to improve error performance.

Abstract: A TOA positioning system can be implemented to improve location estimation of a wireless network device. A first subset of a plurality of reference wireless network devices for determining potential locations of the wireless network device and a second subset of the plurality of reference wireless network devices for determining an estimated location of the wireless network device can be selected. The first and the second subsets can be selected based on a plurality of distance measurements and an average distance and associated with each of the plurality of reference wireless network devices. The potential locations of the wireless network device can be determined based on the first subset of the plurality of reference wireless network devices. The estimated location of the wireless network device can be determined from the potential locations of the wireless network device based on the second subset of the plurality of reference wireless network devices.

Abstract: Disclosed are systems, methods and devices for obtaining round trip time measurements for use in location based services. In particular implementations, a fine timing measurement request message wirelessly transmitted by a first transceiver device to a second transceiver device may permit additional processing features in computing or applying a signal round trip time measurement. Such a signal round trip time measurement may be used in positioning operations.

Abstract: Systems, apparatus and methods for determining a cyclic shift delay (CSD) mode from a plurality of CSD modes is disclosed. A received OFDM signal is converted to a channel impulse response (CIR) signal in the time domain and/or a channel frequency response (CFR) signal in the frequency domain. Matched filters and a comparator are used to determine a most likely current CSD mode. Alternatively, a classifier is used with a number of inputs including outputs from two or more matched filters and one or more outputs from a feature extractor. The feature extractor extracts features in the time domain from the CIR signal and/or in the frequency domain from the CFR signal useful in distinguishing various CSD modes.

Abstract: The present invention discloses a pressure point inspection device, able to press on a plurality of pressure points on liquid crystal display panel for inspecting display condition, the pressure point inspection device includes: lateral adjustment board, lateral adjustment board including a first lateral board and a second lateral board; vertical adjustment board, disposed crossly on lateral adjustment board, vertical adjustment board including first vertical board and second vertical board, able to fold separately; wherein lateral adjustment board and/or vertical adjustment board disposed with a plurality of inspection heads, vertical disposition gap between first lateral board and second lateral board adjustable and lateral disposition gap between first vertical board and second vertical board adjustable. As such, the pressure point inspection device can save time of pressing pressure points on TFT-LCD and improve inspection efficiency and avoid missing pressure point.

Abstract: Systems, apparatus and methods for determining a cyclic shift diversity (CSD) mode are presented. Examples use two different autocorrelations to determine a current CSD mode. Specifically, a delay-based autocorrelation and a cyclic shift-based autocorrelation are each computed then compared to each other, for example, by taking a difference of the two autocorrelations. A multipath signal leads to similar autocorrelations, where as a signal with a CSD mode enabled leads to dissimilar autocorrelations. By examining the number of peaks in the delay-based autocorrelation or the autocorrelation difference, a current CSD mode may be determined.

Abstract: The present invention provides a process for preparing methanol, dimethyl ether, and low carbon olefins from syngas, wherein the process comprises the step of contacting syngas with a catalyst under the conditions for converting the syngas into methanol, dimethyl ether, and low carbon olefins, characterized in that, the catalyst contains an amorphous alloy consisting of a first component Al and a second component, said second component being one or more elements or oxides thereof selected from Group IA, IIIA, IVA, VA, IB, IIB, IVB, VB, VIB, VIIB, VIII, and Lanthanide series of the Periodic Table of Elements, and said second component being different from the first component Al. According to the present process, the syngas can be converted into methanol, dimethyl ether, and low carbon olefins in a high CO conversion, a high selectivity of the target product, and high carbon availability.

Abstract: A method for coating polyimide on liquid crystal display panel includes: (1) providing nozzles and a glass substrate; (2) tightly and regularly juxtaposing the nozzles in a row so that the row has a length that corresponds to width of the glass substrate; (3) vertically positioning the entire row above the glass substrate so as to correspond to the glass substrate along the width of the glass substrate; (4) simultaneously activating the nozzles to allow each of the nozzles to simultaneously drip down polyimide solution according to predetermined flow rate, while moving the glass substrate so as to have the polyimide solution uniformly applied to the glass substrate form a polyimide film; and (5) using a doctor blade to shape the polyimide film that is uniformly coated on the glass substrate so as to provide a regular and flat surface of the polyimide film on the glass substrate.