Abstract: To address challenges in existing 5G wireless networks, a new wireless backhaul scheme, referred to as Fast Wireless Backhaul (FWB), is described. More specifically, in order to reduce handover delays in a network including a gateway device, at least two base stations, and a user equipment device, one of a group of the base stations selected is identified as a primary base station, and each of the other of the group of base stations selected is identified as a secondary base station. A control plane wireless connection is maintained between the user equipment device and each of the preferred base stations selected. A data plane wireless connection is maintained only between the user equipment device and the primary base station.

Abstract: Fifth Generation (5G) Millimeter Wave (mmWave) cellular networks are expected to serve a large set of throughput intensive, ultra-reliable, and ultra-low latency applications. To meet these stringent requirements, while minimizing the network cost, the 3rd Generation Partnership Project has proposed a new transport architecture, where certain functional blocks can be placed closer to the network edge. In this architecture, however, blockages and shadowing in 5G mmWave cellular networks may lead to frequent handovers (HOs) causing significant performance degradation. To meet the ultra-reliable and low-latency requirements of applications and services in an environment with frequent HOs, a Fast Inter-Base Station Ring (FIBR) architecture is described, in which base stations that are in close proximity are grouped together, interconnected by a bidirectional counter-rotating buffer insertion ring network.

Abstract: Due to massive available spectrum in the millimeter wave (mmWave) bands, cellular systems in these frequencies may provide orders of magnitude greater capacity than networks in conventional lower frequency bands. However, due to high susceptibility to blocking, mmWave links can be extremely intermittent in quality. This combination of high peak throughputs and intermittency can cause significant challenges in end-to-end transport-layer mechanisms such as TCP, such as the challenging problem of bufferbloat. Specifically, with current buffering and congestion control mechanisms, high throughput-high variable links can lead to excessive buffers incurring long latency. A dynamic receive window approach addresses the problem of bufferbloat.

Abstract: Fifth Generation (5G) Millimeter Wave (mmWave) cellular networks are expected to serve a large set of throughput intensive, ultra-reliable, and ultra-low latency applications. To meet these stringent requirements, while minimizing the network cost, the 3rd Generation Partnership Project has proposed a new transport architecture, where certain functional blocks can be placed closer to the network edge. In this architecture, however, blockages and shadowing in 5G mmWave cellular networks may lead to frequent handovers (HOs) causing significant performance degradation. To meet the ultra-reliable and low-latency requirements of applications and services in an environment with frequent HOs, a Fast Inter-Base Station Ring (FIBR) architecture is described, in which base stations that are in close proximity are grouped together, interconnected by a bidirectional counter-rotating buffer insertion ring network.

Abstract: Due to massive available spectrum in the millimeter wave (mmWave) bands, cellular systems in these frequencies may provide orders of magnitude greater capacity than networks in conventional lower frequency bands. However, due to high susceptibility to blocking, mmWave links can be extremely intermittent in quality. This combination of high peak throughputs and intermittency can cause significant challenges in end-to-end transport-layer mechanisms such as TCP, such as the challenging problem of bufferbloat. Specifically, with current buffering and congestion control mechanisms, high throughput-high variable links can lead to excessive buffers incurring long latency. A dynamic receive window approach addresses the problem of bufferbloat.

Abstract: Scheduling methods and apparatus for use with optical switches with hybrid architectures are provided. An exemplary distributed scheduling process achieves 100% throughput for any admissible Bernoulli arrival traffic. The exemplary distributed scheduling process may be easily adapted to work for any finite round trip time, without sacrificing any throughput. Simulation results also showed that this distributed scheduling process can provide very good delay performance for different traffic patterns and for different round trip times associated with current switches.

Abstract: Scheduling methods and apparatus are provided for an input-queued switch. The exemplary distributed scheduling process achieves 100% throughput for any admissible Bernoulli arrival traffic. The exemplary distributed scheduling process includes scheduling variable size packets. The exemplary distributed scheduling process may be easily implemented with a low-rate control or by sacrificing the throughput by a small amount. Simulation results also showed that this distributed scheduling process can provide very good delay performance for different traffic patterns. The exemplary distributed scheduling process may therefore be a good candidate large-scale high-speed switching systems.

Abstract: Cooperative communication is a technique that can be employed to meet the increased throughput needs of next generation WiMAX systems. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output system in a distributed fashion. A framework for a randomized distributed space-time coding (“R-DSTC”) technique in the emerging relay-assisted WiMAX network, and the development of a cooperative medium access control (“MAC”) layer protocol, called CoopMAX, for R-DSTC deployment in an IEEE 802.16 system, is described. The technique described couples the MAC layer with the physical (PHY) layer for performance optimization. The PHY layer yields significant diversity gain, while the MAC layer achieves a substantial end-to-end throughput gain.

Abstract: Scheduling methods and apparatus are provided for buffered crossbar switches with a crosspoint buffer size as small as one and no speedup. An exemplary distributed scheduling process achieves 100% throughput for any admissible Bernoulli arrival traffic. Simulation results also showed that this distributed scheduling process can provide very good delay performance for different traffic patterns. The simulation results also showed that packet delay is very weakly dependent on the switch size, which implies that the exemplary distributed scheduling process can scale with the number of switch ports.

Abstract: A distributed and opportunistic medium access control (MAC) layer protocol for randomized distributed space-time coding (R-DSTC), which may be deployed in an IEEE 802.11 wireless local area network (WLAN), is described. Unlike other cooperative MAC designs, there is no need to predetermine, before packet transmission, which stations will serve as relays. Instead, the MAC layer protocol opportunistically recruits relay stations on the fly. Network capacity and delay performance is much better than legacy IEEE 802.11g network, and even cooperative forwarding using one relay station. Avoiding the need to collect the station-to-station channel statistics considerably reduces overhead otherwise required for channel measurement and signaling.

Abstract: Multiple cooperative relays operate in a highly mobile environment and form a virtual antenna array. Multiple independent streams of data can be simultaneously, transmitted in parallel to the destination receiver. Thus a higher spatial multiplexing gain can be obtained. Each relay device that receives the information without errors splits it into multiple streams. For example, if the relay devices receive B symbols and the number of streams is K, each stream contains B/K symbols. Each relay device then generates a random linear combination of all the streams and transmits this output simultaneously with the other relay devices.

Abstract: MD-FEC is considered an efficient way to generate a large number of descriptions. However, typically, MD-FEC introduces significant redundancy across streams. MD-FEC encoded streams (descriptions) are adapted based on feedback. Specifically, the bits sent in each description by a supplying peer are adapted based on the number of available descriptions in its receiving peer. The adaptive delivery eliminates unnecessary bits in the original MD-FEC streams (descriptions), and significantly reduces the consumed uplink bandwidth at supplying peers. The saved bandwidth can be used to accommodate more video sessions or for other applications.

Abstract: Data is transmitted from a source wireless device to a destination wireless device by: (a) discovering node-to-node wireless channel conditions in a wireless network; (b) determining at least one of (A) wireless relay devices, (B) modulation schemes, and (C) transmission rates using the discovered node-to-node channel conditions; (c) signaling at least some of the determined information to the determined wireless relay devices; (d) receiving, with each of the wireless relay devices, a transmission of the data from the source wireless device; and (e) transmitting, with each of the wireless relay devices, a randomized, space-time encoded, part of the received data, to the destination device using the signaled at least some of the determined information.

Abstract: Scheduling methods and apparatus are provided for an input-queued switch. The exemplary distributed scheduling process achieves 100% throughput for any admissible Bernoulli arrival traffic. The exemplary distributed scheduling process includes scheduling variable size packets. The exemplary distributed scheduling process may be easily implemented with a low-rate control or by sacrificing the throughput by a small amount. Simulation results also showed that this distributed scheduling process can provide very good delay performance for different traffic patterns. The exemplary distributed scheduling process may therefore be a good candidate large-scale high-speed switching systems.

Abstract: Scheduling methods and apparatus for use with optical switches with hybrid architectures are provided. An exemplary distributed scheduling process achieves 100% throughput for any admissible Bernoulli arrival traffic. The exemplary distributed scheduling process may be easily adapted to work for any finite round trip time, without sacrificing any throughput. Simulation results also showed that this distributed scheduling process can provide very good delay performance for different traffic patterns and for different round trip times associated with current switches.

Abstract: Improved distribution of video information in an infrastructure-based wireless network is provided. A wireless channel condition between the video server node and each of the plurality of receiver nodes is determined. Receiver nodes are assigned into one of a first group and a second group using the measured wireless channel conditions, wherein receiver nodes assigned to the first group have, on average, a better measured wireless channel condition than that of receiver nodes assigned to the second group. At least some of the receiver nodes of the first group of nodes are selected to serve as relay nodes. Video information is then transmitted wirelessly from the video server node to the receiver nodes assigned to the first group. Each of the selected relay nodes then transmits at least a part of the video information to the receiver nodes of the second group.

Abstract: When it is advantageous to do so, a wireless LAN station sends data packets to a destination station via an intermediate station, instead of to the destination station directly. That is, the intermediate station, which serves as a helper to the source, forwards packets received from the source station to the intended destination station. This cooperative data transmission approach can result in system performance improvement, as long as the total time consumed by two-hop transmission (i.e., transmission via the helper station) is less than direct transmission. Such a determination may be made using rate information stored at each station. Specifically, using the rate information, signaling needed to set up a transmission, the amount of data to be transmitted, etc., transmitting the data directly and via a help station may be compared.

Abstract: Wireless protocols that employ a helper node are adapted so that they may take advantage of authentication security (and perhaps encryption security). Thus, such protocols may be used with security protocols such as 802.11i protocol (or the like) for example.

Abstract: Video multicast over Wireless Local Area Networks (WLANs) faces many challenges due to varying channel conditions and limited bandwidth. A promising solution to this problem is the use of packet level Forward Error Correction (FEC) mechanisms. However, the adjustment of the FEC rate is not a trivial issue due to the dynamic wireless environment. This decision becomes more complicated if one considers the multi-rate capability of the existing wireless LAN technology. A novel method which dynamically adapts the transmission rate and FEC for video multicast over multi-rate wireless networks is described. In order to evaluate the system experimentally, a prototype using open source drivers and socket programming was implemented. Experimental results show that the proposed system significantly improves the multicast system performance.

Abstract: Cooperative communication is a technique that can be employed to meet the increased throughput needs of next generation WiMAX systems. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output system in a distributed fashion. A framework for a randomized distributed space-time coding (“R-DSTC”) technique in the emerging relay-assisted WiMAX network, and the development of a cooperative medium access control (“MAC”) layer protocol, called CoopMAX, for R-DSTC deployment in an IEEE 802.16 system, is described. The technique described couples the MAC layer with the physical (PHY) layer for performance optimization. The PHY layer yields significant diversity gain, while the MAC layer achieves a substantial end-to-end throughput gain.