Abstract: A system is provided for speculative scheduling that includes a base station having a processor. The processor computes an overall schedule for a set of clients. The overall schedule is formed from a set of speculative schedules, is configured to maximize unlicensed spectrum usage, and is computed by (a) determining a speculative schedule for each resource block from a set of resource blocks in a given sub-frame based on statistics determined for the clients individually and jointly, and (b) selecting, for formation into the overall schedule, (i) a particular resource block and (ii) the speculative schedule for the particular resource block, that yield the maximum incremental utility relative to already determined speculative schedules for other resource blocks in the set, based on criteria including uplink access statistics. The processor executes the overall schedule responsive to a completion of the speculative schedule determination for each resource block in the given sub-frame.

Abstract: A system, method, and computer program product are provided for blue-printing interference for mobile access in an unlicensed spectrum of a synchronous scheduled cellular access system. The system includes a cellular base station having a processor. The processor constructs and executes an intelligent measurement schedule of clients for uplink transmissions to obtain access measurements for the uplink transmissions. The intelligent measurement schedule is constructed for scalable access measurement overhead. The access measurements indicate interference dependencies between the clients. The processor estimates an interference topology and statistics of the interference topology, from the access measurements to form an interference blueprint. The processor adjusts the intelligent measurement schedule to overschedule the clients for the uplink transmissions to reduce spectrum utilization loss while minimizing client transmission collisions, based on the interference blueprint.

Abstract: According to an example, a distributed antenna system includes a central processing apparatus and a plurality of antenna apparatuses connected to the central processing apparatus via Ethernet cables through an Ethernet switch. The plurality of antenna apparatuses are spatially distributed with respect to each other and the central processing apparatus is to communicate Ethernet packets to the plurality of antenna apparatuses. In addition, the plurality of antenna apparatuses are to wirelessly transmit signals corresponding to data contained in the Ethernet packets in a substantially coordinated and synchronized manner with respect to each other.

Abstract: Aspects of the present disclosure describe a battery-free touch sensing user interface (UI) for Internet of Things (IoT) and other smart spaces employing Radio Frequency Identification (RFID) readers and tags that we call RIO. With RIO, any surface may be a touch-aware surface by attaching RFID tag(s) thereto. RIO advantageously supports custom-designed RFID tags and therefore facilitates customized UIs to be easily deployed in a real-world environment. RIO employs impedance tracking that results from a human finger—or other appendage—touching a surface of an RFID tag, thereby changing a characteristic impedance of the RFID tag antenna. This change manifests as a change in the phase of the RFID backscattered signal and is advantageously used by RIO to track fine-grained touch movement over the RFID tag. Disclosed further are multi-tag environments in which RIO operates and demonstrations including continuous tracking of finger movement during a swipe to within 3 mm of its actual position.

Abstract: Systems and methods for improving Long Term Evolution (LTE)-WiFi coexistence in a network, including configuring one or more LTE nodes for asynchronous access and synchronous transmission to bridge LTE and WiFi access modes. A channel is reserved for LTE transmission in the one or more LTE nodes, and a supplementary WiFi module is provided in the one or more LTE nodes for sensing the channel for occupancy and for broadcasting a reservation signal on the channel prior to the LTE transmission. Contention window sizes are scaled linearly by increasing the contention window sizes proportionally to a subframe collision rate to maintain throughput fairness to the WiFi, and synchronous transmission from the one or more LTE nodes to one or more User Devices (UEs) is performed by activating the unlicensed carrier for a reserved time period.

Abstract: A method implemented in an access point (AP) used in a wireless communications system including a first uplink (UL) client device, a second UL client device, and a first downlink (DL) client device is disclosed. The method comprises: receiving, from the first DL client device, first composite channel matrix M1 comprising a first channel matrix and a second channel matrix, wherein the first DL client device estimates the first channel matrix and the second channel matrix. Other methods, systems, and apparatuses also are disclosed.

Abstract: Methods and a system are provided for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system. A method includes embedding in a data sequence, by a base station capable of transmitting and receiving LTE frames, a channel reservation packet that (i) is detectable by a WIFI receiver and (ii) reserves a particular one of a plurality of available unlicensed communication channels for a transmission duration of the data sequence. The method further includes transmitting, by the base station, the data sequence including the embedded channel reservation packet.

Abstract: An interference alignment system for communication structures that includes a single cell channel comprising an access point node, and a full bipartite interference channel (FBIC) configuration of a plurality of receiving nodes and a plurality of transmitting nodes. Each receiving node sees an interfering signal from all transmitting nodes. The access point node of the single cell channel provides a single node having downlink channels to all receiving nodes in the FBIC, and all of the uplink channels from the FBIC are to the single access point node to the single cell channel.

Abstract: A method implemented in a wireless communications system including a first uplink (UL) client device, a second UL client device, a first downlink (DL) client device, and an access point (AP) is disclosed. The method comprises the following steps in this order: a) determining interference alignment (IA) solution between the first and second UL client devices and the first device; and b) determining, according to the IA solution, receive filter U0 for the AP and precoder V0 for the AP to improve a UL stream rate and a DL stream rate. Other methods, systems, and apparatuses also are disclosed.

Abstract: A method implemented in an access point (AP) having N antennas used in a wireless communications system including two first client devices each of which has M antennas and two second client devices each of which has N antennas, where M and N are even is disclosed. The method comprises: performing interference alignment (IA) in common vector spaces; and delivering M+N streams. Other methods, systems, and apparatuses also are disclosed.

Abstract: Systems and methods for improving Long Term Evolution (LTE)-WiFi coexistence in a network, including configuring one or more LTE nodes for asynchronous access and synchronous transmission to bridge LTE and WiFi access modes. A channel is reserved for LTE transmission in the one or more LTE nodes, and a supplementary WiFi module is provided in the one or more LTE nodes for sensing the channel for occupancy and for broadcasting a reservation signal on the channel prior to the LTE transmission. Contention window sizes are scaled linearly by increasing the contention window sizes proportionally to a subframe collision rate to maintain throughput fairness to the WiFi, and synchronous transmission from the one or more LTE nodes to one or more User Devices (UEs) is performed by activating the unlicensed carrier for a reserved time period.

Abstract: Methods and systems for beam forming, implemented in a base station used in a communication system, include measuring channel state information (CSI) for a number of active phased-array antennas less than a full number of phased-array antennas. Analog beam forming weights are determined using the measured CSI. An optimal digital precoder is determined from the analog beam forming weights. The analog beam forming weights and optimal digital precoder are applied to one phased-array antenna.

Abstract: Methods and systems of asynchronous access and synchronous transmission include transmitting an initial reservation packet using a first protocol to prevent other devices that use the first protocol from transmitting during a reserved duration. A carrier using a second protocol is activated. Information is transmitted using a second protocol during the reserved duration. During a last subframe of the reserved duration, an additional reservation packet is transmitted using the first protocol to extend the reserved duration. The transmission of the additional reservation packet takes place while the carrier using the second protocol is still active.

Abstract: Methods and systems for beam forming include measuring channel state information for a set of different codebook entries. An angle of arrival (AoA) distribution is determined with a processor using compressive testing based on the measured channel state information. A set of phase shift values is determined based on the determined AoA to perform phased array beamforming.

Abstract: According to an example, a distributed antenna system includes a central processing apparatus and a plurality of antenna apparatuses connected to the central processing apparatus via Ethernet cables through an Ethernet switch. The plurality of antenna apparatuses are spatially distributed with respect to each other and the central processing apparatus is to communicate Ethernet packets to the plurality of antenna apparatuses. In addition, the plurality of antenna apparatuses are to wirelessly transmit signals corresponding to data contained in the Ethernet packets in a substantially coordinated and synchronized manner with respect to each other.

Abstract: A method implemented in an access point (AP) used in a wireless communications system including a first uplink (UL) client device, a second UL client device, and a first downlink (DL) client device is disclosed. The method comprises: receiving, from the first DL client device, first composite channel matrix M1 comprising a first channel matrix and a second channel matrix, wherein the first DL client device estimates the first channel matrix and the second channel matrix. Other methods, systems, and apparatuses also are disclosed.

Abstract: A method implemented in an access point (AP) having N antennas used in a wireless communications system including two first client devices each of which has M antennas and two second client devices each of which has N antennas, where M and N are even is disclosed. The method comprises: performing interference alignment (IA) in common vector spaces; and delivering M+N streams. Other methods, systems, and apparatuses also are disclosed.

Abstract: A method implemented in a wireless communications system including a first uplink (UL) client device, a second UL client device, a first downlink (DL) client device, and an access point (AP) is disclosed. The method comprises the following steps in this order: a) determining interference alignment (IA) solution between the first and second UL client devices and the first device; and b) determining, according to the IA solution, receive filter U0 for the AP and precoder V0 for the AP to improve a UL stream rate and a DL stream rate. Other methods, systems, and apparatuses also are disclosed.

Abstract: Methods and systems for beam forming include measuring channel state information for a set of different codebook entries. An angle of arrival (AoA) distribution is determined with a processor using compressive testing based on the measured channel state information. A set of phase shift values is determined based on the determined AoA to perform phased array beamforming.

Abstract: Methods and systems for beam forming, implemented in a base station used in a communication system, include measuring channel state information (CSI) for a number of active phased-array antennas less than a full number of phased-array antennas. Analog beam forming weights are determined using the measured CSI. An optimal digital precoder is determined from the analog beam forming weights. The analog beam forming weights and optimal digital precoder are applied to one phased-array antenna.