Patent application number | Description | Published |
20090190675 | SYNCHRONIZATION IN A BROADCAST OFDM SYSTEM USING TIME DIVISION MULTIPLEXED PILOTS - In an OFDM system, a transmitter broadcasts a first TDM pilot on a first set of subbands followed by a second TDM pilot on a second set of subbands in each frame. The subbands in each set are selected from among N total subbands such that (1) an OFDM symbol for the first TDM pilot contains at least S | 07-30-2009 |
20090319261 | CODING OF TRANSITIONAL SPEECH FRAMES FOR LOW-BIT-RATE APPLICATIONS - Systems, methods, and apparatus for low-bit-rate coding of transitional speech frames are disclosed. | 12-24-2009 |
20090319262 | CODING SCHEME SELECTION FOR LOW-BIT-RATE APPLICATIONS - Systems, methods, and apparatus for low-bit-rate coding of transitional speech frames are disclosed. | 12-24-2009 |
20090319263 | CODING OF TRANSITIONAL SPEECH FRAMES FOR LOW-BIT-RATE APPLICATIONS - Systems, methods, and apparatus for low-bit-rate coding of transitional speech frames are disclosed. | 12-24-2009 |
20150092753 | HIGH PRECISION ACCESS POINT TO ACCESS POINT SYNCHRONIZATION IN AN INDOOR POSITION LOCATION SYSTEM - Methods, systems, and devices are described that provide for high precision synchronization between pairs of APs within a tracking area of a position location network. These tools and techniques may provide for incrementally synchronizing timers and oscillators located at respective APs. An AP may transmit a course frequency and timing acquisition signal that a second AP utilizes to estimate a frequency offset and/or time offset. The AP may transmit a subsequent fine frequency and timing acquisition signal which may be used to accurately adjust the estimated frequency offset and/or time offset of the second AP. The second AP may thus incrementally synchronize its oscillator(s) and/or timer(s). These techniques may be utilized over a multi-hop wireless network. The methods, systems, and devices may be applicable to single- and multi-floor location tracking systems. | 04-02-2015 |
20150092754 | HIGH PRECISION NETWORK SYNCHRONIZATION IN AN INDOOR POSITION LOCATION SYSTEM - Methods, systems, and devices for synchronizing a position location network. The methods, systems, and/or devices may provide for designating as a master AP one AP from a network. The master AP may broadcast synchronization signals, which other APs in the network may use to synchronize their respective oscillators and/or clocks. In some cases, the master AP and/or a network server (e.g., a tracking management server) may designate acting master APs. The acting master APs may, for example, broadcast synchronization signals to neighboring APs. The acting master APs and/or the master AP may maintain lists of synchronized APs, which may be transmitted among APs and/or to a network server. | 04-02-2015 |
20150092821 | RECEIVE FILTERS TO MINIMIZE SIDE LOBES IN A UWB SYSTEM - Methods, systems, and devices for maximizing signal to interference plus noise ratio of a channel in a location tracking system. The methods, systems, and device may include tools and techniques for minimizing interference from adjacent samples at a receive filter, may include relaxing constraints at a transmitter. A receive filter or set of receive, or both, filters may be determined and utilized by specifying and or determining various transmitter, receiver, and channel characteristics. The receive filter and set of filters may be determined through an iterative approach involving one or more solution metrics. | 04-02-2015 |
20150094081 | DETERMINING COORDINATES OF ACCESS POINTS IN AN INDOOR POSITION LOCATION SYSTEM - Methods, systems, and devices are described for determining and updating coordinates of access points (APs) within a location tracking system. Tools and techniques are described that may provide for automatically determining a coordinate set, which represents coordinates of at least three neighboring APs within a location tracking area. These techniques may be utilized at the time of the APs' deployment and/or when APs are moved or relocated to a new location. The methods, systems, and devices may be applicable to single- and multi-floor location tracking systems. Coordinate and/or coordinate sets of APs may be stored in a location tracking server, and they may used in determining a location of tracking tags with the location tracking area. The stored coordinates and/or coordinate sets may be updated as the location of APs change. | 04-02-2015 |
20150094082 | CHANNEL ESTIMATION USING CYCLIC CORRELATION - Methods, systems, and devices for channel estimation and/or earliest path detection in a location tracking system are described. The described tools and techniques may involve accumulation of energy of multiple copies of a periodic sequence, which may be contained and/or associated with a signal transmitted from a location tracking tag. One or more access points within the location tracking system may receive and process multiple copies of the sequence, employing period-wise coherent accumulation, and estimate an earliest path, or a corresponding delay associated with an earliest path, of the sequence. The access point(s) may transmit information related to the earliest path, including the corresponding delay, to a tracking management server, which may use the information to estimate and/or determine a location of a tag. | 04-02-2015 |