Abstract:
An Orthogonal Spatial Multiplexing (OSM) apparatus and method in a closed-loop Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system are provided. In the OSM method, a basic signal model is set and transmission symbols are encoded. A real-valued system model corresponding to the basic signal model is obtained. To achieve orthogonality, rotations angles are calculated and are applied to the encoded transmission symbols.
Abstract:
A method is provided for efficiently allocating a transmission period in a wireless network system. An access point (AP) transmits a PSMP frame indicating a downlink period provided to each station (STA) and a minimum amount of an uplink period allocated to each STA, and at least one sub PSMP frame indicating an uplink period additionally provided for an STA that transmitted a resource request message for remaining queued data in the uplink period indicated by the PSMP frame. If the uplink period indicated by the PSMP frame is insufficient to transmit the queued data, the STA transmits a data unit including a part of the queued data and a resource request message for the remaining queued data in the uplink period. After transmitting the resource request message, the STA receives the sub PSMP frame after the full period indicated by the sub PSMP frame, and transmits the remaining queued data to the AP in the uplink period indicted by the sub PSMP frame.
Abstract:
An apparatus and method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.
Abstract:
A method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.
Abstract:
Read-write head flying height controlled through micro-actuator assembly. Flying height controlled using DC line and ground line. Lateral position controlled using them and AC line. Micro-actuator assembly operates through three terminals coupled with these lines. Head gimbal assembly contains micro-actuator assembly mechanically coupling to slider with read-write head. Actuator arm includes at least one head gimbal assembly. Actuator arm assembly includes at least one actuator arm. Voice coil actuator includes actuator assembly. Hard disk drive containing voice coil actuator. Electrical interface circuit includes ground port, DC port, and AC port, for micro-actuator assembly. Servo controller drives micro-actuator assembly to control flying height and lateral position, preferably including electrical interface circuit. Manufacturing head gimbal assembly, actuator arm, actuator assembly, voice coil actuator, and hard disk drive, and products of these manufacturing processes.
Abstract:
A spin-on glass (SOG) composition and a method of forming a silicon oxide layer utilizing the SOG composition are disclosed. The method includes coating on a semiconductor substrate having a surface discontinuity, an SOG composition containing perhydropolysilazane having a compound of the formula —(SiH2NH)n— wherein n represents a positive integer, a weight average molecular weight within the range of about 4,000 to 8,000, and a molecular weight dispersion within the range of about 3.0 to 4.0, to form a planar SOG layer. The SOG layer is converted to a silicon oxide layer with a planar surface by curing the SOG layer. Also disclosed is a semiconductor device made by the method.
Abstract:
A power saving apparatus and a method in a wireless communication system are provided. An Access Point (AP) buffers transmission frames for sleep-mode stations in a sleep-mode buffer. Upon wakeup from a sleep mode, a station sends a first control information frame indicating wakeup to the access point. The access point sends a second control information frame including a requested transmission length in response to the first control information frame to the station. The station generates a third control information frame, aggregates the third control information frame and user data frames to a first protocol data unit, and sends it to the AP. Then the AP generates a fourth control information frame, aggregates the fourth control information frame and buffered frames to a second protocol data unit, and sends it to the station.
Abstract:
A TDM (Time Division Multiplexing)-based mobile communication system that switches a service type according to QoS (Quality of Service). The mobile communication system includes a base transceiver system (BTS) and a mobile station (MS) connected to the BTS. The BTS monitors whether a first service provided from the BTS to the MS is satisfied according to whether at least as much data as a predetermined transmission amount is transmitted to the MS. If the first service is dissatisfied, the BTS switches a service to a second service lower in QoS than the first service so that as much data as a transmission amount smaller than the predetermined transmission amount is transmitted to the MS.
Abstract:
A base station controller (BSC) performs a handoff of a mobile terminal (MT) moving between cells of base transceiver stations (BTSs) in a mobile communication system. If a target BTS is selected as a handoff candidate for the MT as the MT moves from a cell of a source BTS in service toward a cell of the target BTS, the BSC transmits to the target BTS a first message for requesting the target BTS to buffer packets, and transmits packets to be transmitted to the MT to both the source BTS and the target BTS. If the target BTS is determined as a serving BTS for the MT, the BSC transmits to the target BTS a second message including a last sequence number in order to request the target BTS to transmit, to the MT, packets with sequence numbers following the last sequence number of a last packet transmitted from the source BTS to the MT, among the buffered packets.
Abstract:
In one embodiment, adjacent conductive patterns are formed overlying a semiconductor substrate. The conductive patterns each have a conductive line and a capping layer. A first spacer formation layer is formed between the adjacent conductive patterns. The first spacer formation layer is formed between the top surface of the capping layer and the bottom surface of the conductive line. A conformal second spacer formation layer is formed on the conductive patterns. A first interlayer insulating layer is formed on the conformal second spacer formation layer. Next, an opening is formed to extend to a portion of the first spacer formation layer, in the first interlayer insulating layer. The portion of the first spacer formation layer is etched, using the second spacer formation layer as an etch mask, to form a single-layer spacer on sidewalls of the conductive patterns, concurrently with a contact hole.