Abstract: An opportunistic hybrid-relay selection scheme for downlink transmission selects between cooperative relay and single relay schemes based on the channel conditions (e.g., signal-to-noise-ratio (SNR)) between the base station (BS) and RSs (i.e., BS-RSs link) and RSs and mobile station (MS) (i.e., RSs-MS link), respectively. In another selection scheme, a selection between the single relay (e.g., best-relay) transmission scheme or the cooperative-relay transmission scheme may be determined based on transmission paths (e.g., line-of-sight, obstructed-light-of-sight, non-light-of-sight) and channel conditions (e.g., SNR) between the BS-RSs link and the RSs-MS link, respectively.

Abstract: A method and apparatus is disclosed herein for synchronized multi-link transmission in an ARQ-enabled multi-hop wireless network. In one embodiment, the method comprises performing pre-transmission of a packet to hops to enable a base station and the plurality of hops in the network to transmit the packet synchronously to one or more mobile stations in the wireless communication system; and performing one or more re-transmissions of the packet at a set of one or more hops forming a path in the network if time remaining before a synchronized transmission time for the path as a whole is greater than a threshold.

Abstract: A relaying selection and cooperative communications method provides a threshold selection criterion for forming a reliable group of relay stations (RSs) based on one or more design criteria. Possible design criteria include an outage probability constraint and a throughput constraint. The threshold value is selected according to, for example, transmission paths (e.g., line-of-sight, obstructed-light-of-sight, non-light-of-sight) or channel conditions (e.g., signal-to-noise-ratio) between the base station (BS) and the RSs (i.e., BS-RSs link) and between the RSs and the mobile station (MS) (i.e., RSs-MS link), respectively.

Abstract: A method and apparatus is disclosed herein for transmitting data in a network (e.g., a relay network). In one embodiment, the method comprises performing pre-transmission of a packet to hops to enable the base station and the plurality of hops to transmit the packet synchronously to one or more mobile stations in the wireless communication system; and performing one or more re-transmissions of the packet at a first set of one or more hops in the system during a delay due to pre-transmissions at a second set of one or more hops in the system.

Abstract: The following invention related to a dynamic on-off spectrum access scheme that will coordinate among different cells, sharing the same spectrum band and enhance spectrum efficiency. Based on the proposed scheme, in particular, the cells or sectors are classified to different types according to their geographical locations. Different types of cells or sectors occupy the total available frequency in a time-sharing fashion, and the duration or priority of the “on” state for each type is chosen based on users' quality of service (QoS) demand.

Abstract: A linear least squares (LLS) estimator provides a low complexity estimation of the location of a mobile terminal (MT), using one of the fixed terminals (FTs) as a reference FT to derive a linear model. A method for selecting a reference FT is disclosed, which improves the location accuracy relative to an arbitrary approach to selecting the reference FT. In addition, a covariance-matrix based LLS estimator is proposed in line-of-sight (LOS) and non-LOS (NLOS) environments to further provide accuracy, taking advantage of the correlation of the observations. Different techniques for selecting the reference FT under non-LOS (NLOS) conditions are disclosed. A map-based two-stage LLS estimator assists in selecting the reference FT under NLOS conditions.

Abstract: A base station (BS) communicates with a mobile station (MS) through relay stations (RSs). In one exemplary reliable relay-associated transmission scheme, the BS transmits data to the RSs using multicast or unicast. From the received packets, each RS calculates its reliability value according to a reliability function, which it informs the MS. The BS then generates a reliability metric to identify the RSs that are considered reliable. The reliable RSs transmit their information to the MS under a cooperative multicast transmission mode. Meanwhile, the unreliable RSs overhear the transmissions between the reliable RSs and the target MS. If the MS is unable to receive information from reliable RSs, the unreliable RSs can join the cooperative transmission to provide a higher cooperative diversity gain to the target MS.

Abstract: A method supports scalable and reliable multicast in a wireless network with a large bandwidth-delay product. In this method, acknowledgement packets from different receivers experiencing the same number of data packets lost are assigned the same time slots. This method can be combined with other loss recovery techniques, such as forward error correction (FEC) recovery, proactive protection, feedback suppression and collision detection. Scalability is achieved as bandwidth usage relates only to the number of packets transmitted, rather than the number of receivers.

Abstract: In a geolocation application, a method is provided to jointly estimate the time-of-arrival (TOA) and the amplitude of a received signal based on super-resolution technique. The super-resolution joint TOA-amplitude estimators are provided based on either the expectation-maximization (EM), parallel-interference-cancellation space-alternating generalized expectation maximization (PIC-SAGE) or serial-interference-cancellation SAGE (SIC-SAGE). The SIC-SAGE estimator minimizes the ranging estimation error especially under a non-line-of-sight (NLOS) condition. The SIC-SAGE estimator is a simplified version of the maximum likelihood estimator with more stable performance in a multipath rich environment, such as the ultra-wideband (UWB) based applications. These techniques provide the following benefits: 1) it is generic, so that signal processing can be deployed on both time-domain (e.g., UWB impulse-radio) and frequency-domain (e.g.

Abstract: Apparatuses and methods are disclosed herein for implementing dormant mode with paging in a WLAN. Power savings in the computing device and reduction in traffic across the network are achieved by requiring a computing device to inform the WLAN of its location only when it crosses a paging area boundary or is to receive IP traffic. Dormant mode with paging is implemented in a protocol that supports dormant functionality and paging functionality but does not itself provide methods or standards for implementing such functionality, such as the IEEE 802.11. The methods and apparatuses disclosed herein provide the methods needed to implement dormant mode with paging in such a protocol. Generally, the methods and apparatuses for implementing dormant mode with paging basically include (1) establishing paging areas; (2) communicating access group information to a computing device; and (3) locating a computing device.

Abstract: Apparatuses and methods are disclosed herein for implementing dormant mode with paging in a WLAN. Power savings in the computing device and reduction in traffic across the network are achieved by requiring a computing device to inform the WLAN of its location only when it crosses a paging area boundary or is to receive IP traffic. Dormant mode with paging is implemented in a protocol that supports dormant functionality and paging functionality but does not itself provide methods or standards for implementing such functionality, such as the IEEE 802.11. The methods and apparatuses disclosed herein provide the methods needed to implement dormant mode with paging in such a protocol. Generally, the methods and apparatuses for implementing dormant mode with paging basically include (1) establishing paging areas; (2) communicating access group information to a computing device; and (3) locating a computing device.

Abstract: A method and communication system for supporting dormant mode are described. In one embodiment, the communication system comprises a wireless station operable in a power savings mode and group of access points. Each group of access points comprises one or more access points with at least one group of access points having at least two access points. Ranges for the one or more access points in each of the groups define a paging area for each group, wherein one access point uses a paging channel for paging the wireless station when the wireless station is in the power savings mode and is in the paging area associated with the one access point.

Abstract: A wireless communication system experience interference from other wireless communication networks. A method for designing wireless communication systems subject to interference is proposed based on a realistic interference model which accounts for the propagation effects introduced by the wireless environment (such as path loss, shadowing, and multipath fading), and for the spatial scattering of transmitters (using a Poisson field). The method accounts for tradeoffs between network parameters, such as signal-to-noise ratio (SNR), interference-to-noise ratio (INR), path loss exponent, spatial density of the interferers, and error probability. Advantages of this method include: 1) a unified framework for designing a wireless system, subject to cumulative interference and noise, incorporating a wide range of performance metrics; and 2) a general application that covers a broad class of wireless communication systems and channel fading distributions.

Abstract: A wireless communication system and a detect-and-multiplex (DAM) spectrum sharing technique eliminate contention by secondary spectrum users by multiplexing multiple access methods. Suitable multiple access methods include time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA), space division multiple access (SDMA), orthogonal frequency division multiple access (OFDMA), spectral nulling (SN) or a hybrid scheme (HS) based on a combination of two or more of the above techniques. Unlike, detect-and-avoid (DAA) multiple access methods, the DAM method increases spectrum usage efficiency, and allows more users to share the same region of the spectrum.

Abstract: An apparatus and a method proactively manage the load of an 802.11 WLAN based on one or more per-class station counts, in which the stations are classified according to access categories (ACs), user priorities (UPs), or services. Alternatively, the load of an 802.11 WLAN may also be proactively managed based on provisional or non-provisional per-class traffic specification (TSPECs), depending upon the status of traffic streams (TSs). Load balancing may be achieved by (a) collecting per-class station count information, either through an AP, or through exchanges with neighboring APs or wireless stations, and (b) proactively influencing association decisions between wireless stations and APs. A wireless station may be classified according to ACs, UPs, or services.

Abstract: Disclosed herein are systems and methods for communicating a number of data flows on a single communications channel. In one embodiment, a method of communicating a number of data flows on a shared communications channel includes the acts of (1) calculating a set of optimum goodput rates for the data flows, in order to maximize a total utility of the data flows, (2) calculating a set of optimum throughput rates for the data flows based on the optimum goodput rates, and (3) transmitting the data flows on the shared communications channel with the optimized throughput rates. Optimization is preferably done using utility functions that indicate the utility of the data flows as a function of their goodput rates. The method can additionally block temporarily a transport layer of at least one of the data flows if the transport layer of that data flow is bottlenecked.

Abstract: The following invention relates to geolocation technology. In particular, the proposed method can be used to determine the optimum threshold value that minimizes the estimation error. The proposed method also allows the threshold value to be varied adaptively according to the signal-to-noise ratios (SNRs) under consideration. This is to ensure that the optimum threshold value is being selected under all channel conditions i.e., both line-of-sight (LOS) and non-LOS (NLOS) scenarios. Additionally, the proposed method is generic and system independent in which it can be applied to both coherent (e.g., match filter (MF)) and non-coherent receivers (e.g., energy detector (ED)).

Abstract: A method and an apparatus select an access point (AP) in a wireless LAN to associate or reassociate, based on considerations that take into account the quality-of-service (QoS) status of the stations (STAs) and the potential hidden terminal effect. The method utilizes advertised or requested information obtained from an AP which includes the QoS status in each basic service set (BSS) and estimates the potential hidden terminal (HT) effect based on local channel sensing by the STA. The method selects the AP in a manner that reduces the possibility of collision from equal and higher priority HTs, thus providing greater transmission throughput and improving performance.

Abstract: A system and method for using subnet relations to determine paging areas, for performing authentication and association, and to activate access network interfaces in wireless communication devices in a heterogeneous access network. Paging areas are generated using subnet relations by determining mobility agent servers within a predetermined number of subnet relations from a last active mobility agent server. Authentication and association are also accomplished using subnet relations. Access network interfaces can also be turned on and off based on subnet relations thereby conserving battery power.

Abstract: Apparatuses and methods are disclosed herein for implementing dormant mode with paging in a WLAN. Power savings in the computing device and reduction in traffic across the network are achieved by requiring a computing device to inform the WLAN of its location only when it crosses a paging area boundary or is to receive IP traffic. Dormant mode with paging is implemented in a protocol that supports dormant functionality and paging functionality but does not itself provide methods or standards for implementing such functionality, such as the IEEE 802.11. The methods and apparatuses disclosed herein provide the methods needed to implement dormant mode with paging in such a protocol. Generally, the methods and apparatuses for implementing dormant mode with paging basically include (1) establishing paging areas; (2) communicating access group information to a computing device; and (3) locating a computing device.