Abstract: A radar, or other repetitive interference, detection and data flow control system and method for RF data transmissions uses an RF detector and an omni directional antenna to detect radar or similar signals. The information from the RF detector is communicated to a hub data transmission unit which processes the data about the signal provided by the detector. This information is used by the hub to schedule communications between the hub and subscriber units so that none of the communications between the hub and subscriber fall within the time period of the interfering pulses. Although there are no communications during the time periods of the pulses, the efficiency of communications is improved because collisions and retransmission of data are avoided.
Type:
Grant
Filed:
November 14, 2007
Date of Patent:
March 9, 2010
Assignee:
Adaptix, Inc.
Inventors:
Jerry Prismantas, Jean-Francois Grenon, Lycklama A'nyeholt Heinz, Randy J. Karr, Bruce C. Rothaar
Abstract: A communications base station is installed at a selected new location and the base station, prior to going “on line” monitors the wireless traffic from other base stations within interference range of the new base station's coverage area. The new base station also monitors the wireless traffic between mobile devices within its coverage area and these other base stations. Based upon these monitored conditions, as well as other known conditions, the new base station then determines the transmitting parameter configuration it should imply in order to achieve a desired optimization between capacity and coverage area. After the new base station is on line, a central control can monitor the entire network to determine if any additional changes are necessary and if so the new transceiver, or any other transceiver, can be instructed to monitor itself with respect to interference and to take corrective action to improve overall network coverage and capacity.
Abstract: A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.
Type:
Grant
Filed:
October 31, 2007
Date of Patent:
January 19, 2010
Assignee:
Adaptix, Inc.
Inventors:
Xiaodong Li, Hui Liu, Wenzhong Zhang, Kemin Li
Abstract: A method and apparatus for combining signals of multiple users onto a common channel is disclosed. In one embodiment, the method comprises identifying one or more traffic channels that are of one or more predetermined quality levels to a plurality of subscriber units based on channel profiles of the plurality of subscriber units and transmitting phase modulation multiplexed signals to the plurality of subscriber units through a common set of one or more channels having higher quality than the one or more predetermined quality levels.
Abstract: A method and apparatus for subcarrier selection for systems is described. In one embodiment, the system employs orthogonal frequency division multiple access (OFDMA). In one embodiment, a method for subcarrier selection comprises a subscriber measuring channel and interference information for subcarriers based on pilot symbols received from a base station, the subscriber selecting a set of candidate subcarriers, providing feedback information on the set of candidate subcarriers to the base station, and receiving an indication of subcarriers of the set of subcarriers selected by the base station for use by the subscriber.
Abstract: A method and apparatus for antenna switching, grouping, and channel assignments in wireless communication systems. The invention allows multiuser diversity to be exploited with simple antenna operations, therefore increasing the capacity and performance of wireless communications systems. Channel characteristics indicative of signal reception quality for downlink or bi-directional traffic for each channel/antenna resource combination are measured or estimated at a subscriber. Corresponding channel characteristic information is returned to the base station. Channel characteristics information may also be measured or estimated for uplink or bi-directional signals received at each of multiple receive antenna resources. The base station employs channel allocation logic to assign uplink, downlink and/or bi-directional channels for multiple subscribers based on channel characteristics measured and/or estimated for the uplink, downlink and/or bi-directional channels.
Abstract: A method and apparatus for combining signals of multiple users onto a common channel is disclosed. In one embodiment, the method comprises identifying one or more traffic channels that are of one or more predetermined quality levels to a plurality of subscriber units based on channel profiles of the plurality of subscriber units and transmitting phase modulation multiplexed signals to the plurality of subscriber units through a common set of one or more channels having higher quality than the one or more predetermined quality levels.
Abstract: A method and apparatus for subcarrier selection for systems is described. In one embodiment, the system employs orthogonal frequency division multiple access (OFDMA). In one embodiment, a method for subcarrier selection comprises a subscriber measuring channel and interference information for subcarriers based on pilot symbols received from a base station, the subscriber selecting a set of candidate subcarriers, providing feedback information on the set of candidate subcarriers to the base station, and receiving an indication of subcarriers of the set of subcarriers selected by the base station for use by the subscriber.
Abstract: A method and apparatus for antenna switching, grouping, and channel assignments in wireless communication systems. The invention allows multiuser diversity to be exploited with simple antenna operations, therefore increasing the capacity and performance of wireless communications systems. Channel characteristics indicative of signal reception quality for downlink or bi-directional traffic for each channel/antenna resource combination are measured or estimated at a subscriber. Corresponding channel characteristic information is returned to the base station. Channel characteristics information may also be measured or estimated for uplink or bi-directional signals received at each of multiple receive antenna resources. The base station employs channel allocation logic to assign uplink, downlink and/or bi-directional channels for multiple subscribers based on channel characteristics measured and/or estimated for the uplink, downlink and/or bi-directional channels.
Abstract: A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.
Type:
Application
Filed:
March 6, 2009
Publication date:
July 2, 2009
Applicant:
Adaptix, Inc.
Inventors:
Xiaodong Li, Hui Liu, Wenzhong Zhang, Kemin Li
Abstract: A method and system for cooperative multiple-input multiple output (MIMO) transmission operations in a multicell wireless network. Under the method, antenna elements from two or more base stations are used to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions to and from one or more terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.
Abstract: A method and system for cooperative multiple-input multiple output (MIMO) transmission operations in a multicell wireless network. Under the method, antenna elements from two or more base stations are used to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions to and from one or more terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.
Abstract: A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.
Type:
Grant
Filed:
October 31, 2007
Date of Patent:
February 10, 2009
Assignee:
Adaptix, Inc.
Inventors:
Xiaodong Li, Hui Liu, Wenzhong Zhang, Kemin Li
Abstract: A method and apparatus for subcarrier selection for systems is described. In one embodiment, the system employs orthogonal frequency division multiple access (OFDMA). In one embodiment, a method for subcarrier selection comprises each of multiple subscribers measuring channel and interference information for subcarriers based on pilot symbols received from a base station, at least one of subscribers selecting a set of candidate subcarriers, providing feedback information on the set of candidate subcarriers to the base station, and the one subscriber receiving an indication of subcarriers of the set of subcarriers selected by the base station for use by the one subscriber.
Type:
Grant
Filed:
August 8, 2005
Date of Patent:
November 18, 2008
Assignee:
Adaptix, Inc.
Inventors:
Xiaodong Li, Hui Liu, Kemin Li, Wenzhong Zhang
Abstract: A method and system for cooperative multiple-input multiple output (MIMO) transmission operations in a multicell wireless network. Under the method, antenna elements from two or more base stations are used to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions to and from one or more terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.
Abstract: A method and system for cooperative multiple-input multiple output (MIMO) transmission operations in a multicell wireless network. Under the method, antenna elements from two or more base stations are used to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions to and from one or more terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.
Abstract: A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.
Type:
Application
Filed:
October 31, 2007
Publication date:
September 11, 2008
Applicant:
Adaptix, Inc.
Inventors:
Xiaodong Li, Hui Liu, Wenzhong Zhang, Kemin Li
Abstract: A method for subcarrier allocation and loading for a multi-carrier, multi-subscriber system is described. At least one cluster in a first and second set of clusters of subcarriers is associated for use in communication with a first and second subscriber, respectively. Then, for each cluster associated for use in communication with the first subscriber and the second subscriber, usage of that cluster is multiplexed between the first subscriber during a first time division and the second subscriber during a second time division.
Abstract: A system and method of signal detection is provided. A received signal may be correlated with combinations of reference signals, each combination representing a subset of the reference signals, rather than being correlated with each reference signal individually. Once the timing offset has been found, the specific reference signal matching the received signal may be found with a one-dimensional (1D) search. A large 2-D search is thus reduced to a smaller 2-D search followed by a 1-D search. The system and method may be applied to downlink initial acquisition in mobile WiMAX systems.
Abstract: The present invention is directed to a system and method which mobile devices can be handed from one access point to another while maintaining continuous communication with a network and without changing the device's IP address. In an embodiment, when a device is leaving the air interface range of its home access point, it establishes a connection with an intermediary access point. In an embodiment, the communications from the network are directed to the original access point using the original IP address for the device, and forwarded to the device via the intermediary access point. Communications from the device are routed through the intermediary access point and then either directly to the network, or else through the home access point to the network. The IP address handoff is repeated between intermediary access points until the device either returns to the home access point or ceases communication with the network.