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: One aspect of the present invention regards a method of coordinating the handoff of a mobile carrier between a first access network and a second access network, the method including handing off from a first access network that the mobile carrier is currently operating within to a second access network and building physical access network topology based on the handing off without input from either the first access network or the second access network.

Abstract: A method for detecting a subject's stress level associated with an activity includes (a) connecting the subject to a sensor that senses a value of a biometric; (b) during the activity, (i) repeatedly sensing the value of the biometric over each of a plurality of time windows; and (ii) computing, for each time window, a deviation in the sensed values of the biometric; and (c) detecting the stress level based on the computed deviations. In one implementation, the value of the biometric is a skin temperature measurement. The method may be implemented as an application in a wireless handheld device, such as a cellular telephone.

Abstract: A method determines an optimum bandwidth that minimizes ranging error in a geolocation application. The method ensures that an optimum bandwidth is selected under all channel conditions (i.e., both line-of-sight (LOS) and non-LOS (NLOS) conditions). Additionally, the method is generic and system-independent, such that it is applicable to both coherent receivers (e.g., match filter (MF) based receivers), non-coherent receivers (e.g., energy detector (ED) based receivers) and any types of time-of-arrival (TOA) estimators (e.g., whether peak-detection or threshold-based TOA estimator), regardless of the signal-to-noise ratios (SNRs) under consideration.

Abstract: A non-cyclic evolving-type user resource structure applicable for use in the uplink and the downlink of an OFDMA system with large null guard tones (e.g., a 3GPP LTE system) is provided. In one example, the user resource structure combines the benefits of localized and distributed types of resource structures available in the current baseline 3GPP LTE (Release 8) specifications, and is especially suitable for operating in a fast time-varying channel. In another example, the non-cyclic evolving-type resource structure may be simplified to have no more than three stages: a band-type first stage, a partially evolved-type second stage and an interleaved-type third stage. Depending upon the target or average mobile speed and packet length, the resource structure may even have less than three stages.

Abstract: A handoff key is provided for facilitating a hand off of a wireless terminal from a first access point to a second access point. The handoff key may be generated by a server and communicated to the first and second access points. Alternatively, the handoff key may be generated one of the access points and transmitted to the other access point. The first access point may transmit the handoff key to the wireless terminal before the handoff. Shortly after the handoff, the wireless terminal and the second access point may communicate data encrypted with the handoff key. Later, an authentication server may authenticate the wireless terminal, causing the second access point to provide the wireless terminal with a session key. Thereafter, the wireless terminal and the second access point may communicate data encrypted with the session key.

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 a receiver are provided for demodulating a received multi-carrier modulated signal. The demodulation procedure includes (a) multiplying the received multi-carrier modulated signal with its complex conjugate to obtain a squared signal; (b) multiplying the squared signal with a signal having a frequency 2 ? ? T to obtain a product signal, where T represents a duration of a symbol in the received multi-carrier modulated signal; and integrating the product signal over the duration T. The signal having a frequency 2 ? ? T may be a complex signal having the form exp ? ( j ? ? 2 ? ? T ? t ) ? ? or ? ? exp ? ( - j ? ? 2 ? ? T ? t ) , , or a cosinusoidal signal having the form cos ? ( j ? ? 2 ? ? T ? t ) , , according to whether the multi-carrier modulated signal is a complex signal or a real signal.

Abstract: An evolving-type resource structure supports high data rate services at high mobile speeds. The evolving-type resource structure is an efficient diversity-exploiting user resource structure for fast time-varying frequency-selective fading channel environments. In one example, an evolving-type resource structure takes advantages of both band-type and interleaved-type structures which exploit both multiuser diversity and frequency diversity in fast time-varying channels. The evolving-type resource structure is applicable to centralized, semi-distributed and distributed access schemes and may be used in both downlink (DL) and uplink (UL) transmissions in a cellular system.

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: Methods for increasing power saving in a station that sends or receives frames in an ad hoc wireless network (e.g., IBSS), while allowing the station to enter a power-saving mode quickly upon completion of scheduled tasks. At the same time, a method of the present invention allows two stations in the ad hoc wireless network to infer each other's power management mode without requiring an ATIM/ACK exchange between the STAs within an ATIM window. Consequently, a station may enter a power-saving mode promptly without impairing the station's ability to receive packets. In one embodiment, a “more data” field is used between stations to exchange information. Stations with various computation abilities provide information under different time constraints. The stations may enter power-saving modes that send multicast/broadcast frames or use promiscuous mode within an ATIM window.

Abstract: A method and a communication system including femtocells within a macrocell efficiently manage interference between the different femtocells, and between each femtocell and a macrocell. An efficient frequency assignment scheme for the femtocells minimizes interference between a femtocell and a macrocell and among different femtocells using a spectrum-sensing technique carried out by the femtocells. The frequency assignment scheme selects a suitable channel from a set of candidate channels and ensures that the femtocell has an acceptable coverage area even when it is close to the macrocell base station (BS). The frequency assignment scheme favors a co-channel implementation to take advantage of the hand-off and cell search characteristics of the co-channel implementation. In one embodiment, a joint power control and frequency band assignment technique is used, which partitions the coverage area of the macrocell into an inner region, a power control region, and an outer region.

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: Channel scanning for wireless networks, such as Wireless Local Area Networks (WLANs), generally provides a wireless station with the information on the available WLAN resources, such as the frequency band and the maximum transmission power. The present invention provides safe and fast domain-aware channel scanning, enabling a wireless station to comply with applicable local regulations, in spite of the possibility of domain changes, with short channel-scanning time. Fast channel scanning is accomplished by active channel scanning if valid domain information is available and there is no possibility of domain change. Also, domain-independent channels, if any, are first scanned using active scan to get domain information faster.

Abstract: Silica gel is impregnated as an impregnating substance into pores of an activated carbon having mesopores and macropores. Since the mesopores and the macropores are impregnated with the silica gel, they are made narrow and small whereby a pore size ratio within a range of 1 to 10 nm is increased.

Abstract: The present invention provides a method and system for handoff in a wireless communication network. In one embodiment, a common handoff encryption key is generated by an authentication server and transmitted to a first access point and a second access point. The first access point transmits the handoff encryption key to a wireless terminal. The wireless terminal encrypts output data with the handoff encryption key. When the wireless terminal is associated with the second access point, the second access point decrypts data from the wireless terminal with the handoff encryption key. In a second embodiment, a handoff WEP key generation secret parameter is provided to a first and a second access point. Both access points generate a handoff WEP key as a function of the handoff WEP key generation secret parameter and an address of a wireless terminal. The first access point transmits the handoff WEP key to the wireless terminal.

Abstract: The present invention provides a method and system for handoff in a wireless communication network. In one embodiment, a common handoff encryption key is generated by an authentication server and transmitted to a first access point and a second access point. The first access point transmits the handoff encryption key to a wireless terminal. The wireless terminal encrypts output data with the handoff encryption key. When the wireless terminal is associated with the second access point, the second access point decrypts data from the wireless terminal with the handoff encryption key. In a second embodiment, a handoff WEP key generation secret parameter is provided to a first and a second access point. Both access points generate a handoff WEP key as a function of the handoff WEP key generation secret parameter and an address of a wireless terminal. The first access point transmits the handoff WEP key to the wireless terminal.

Abstract: The present invention provides a method and system for handoff in a wireless communication network. In one embodiment, a common handoff encryption key is generated by an authentication server and transmitted to a first access point and a second access point. The first access point transmits the handoff encryption key to a wireless terminal. The wireless terminal encrypts output data with the handoff encryption key. When the wireless terminal is associated with the second access point, the second access point decrypts data from the wireless terminal with the handoff encryption key. In a second embodiment, a handoff WEP key generation secret parameter is provided to a first and a second access point. Both access points generate a handoff WEP key as a function of the handoff WEP key generation secret parameter and an address of a wireless terminal. The first access point transmits the handoff WEP key to the wireless terminal.

Abstract: The present invention provides a method and system for handoff in a wireless communication network. In one embodiment, a common handoff encryption key is generated by an authentication server and transmitted to a first access point and a second access point. The first access point transmits the handoff encryption key to a wireless terminal. The wireless terminal encrypts output data with the handoff encryption key. When the wireless terminal is associated with the second access point, the second access point decrypts data from the wireless terminal with the handoff encryption key. In a second embodiment, a handoff WEP key generation secret parameter is provided to a first and a second access point. Both access points generate a handoff WEP key as a function of the handoff WEP key generation secret parameter and an address of a wireless terminal. The first access point transmits the handoff WEP key to the wireless terminal.

Abstract: A mobile communication system uses a multiple-input-multiple-output (MIMO) technology with an orthogonal frequency division multiplexing access (OFDMA) scheme. Multiuser diversity, multiantenna diversity, and power control since the first ranging attempt are exploited in the initial ranging process. At network entry, an initial ranging method selects from multiple ranging signal designs to accomplish the initial ranging process. In one embodiment, three classes of ranging signal designs may be selected for use in generating ranging codes. The information on the ranging signal design to be used, which is selected by the base station based on the cell size of the communication system (i.e., the radio coverage area of the base station), is broadcast from the BS. The ranging signal designs are directly applicable to single-antenna systems, and they are applied to MIMO systems by using appropriate mapping across transmit antennas based on the adopted MIMO ranging transmission scheme.