Abstract:
The present invention relates to a method for optimizing power/ground pads in a power/ground distribution network. A power/ground distribution network is created for each of multiple voltage domains and a load current source of each node of the power/ground distribution network is modeled in consideration of the actual shapes and areas of functional blocks. A local optimization method is developed to solve problems generated when a conventional optimization method is applied to optimization of power/ground pads in a bump shape used for a flip chip, and a combination of global optimization and local optimization is applied to layouts using bump bonding, which is discriminated from the conventional optimization method restrictively applicable to layouts using wire bonding.
Abstract:
Disclosed herein is a single wavelength bi-directional optical transceiver for transmitting/receiving optical signals having the same wavelength through an optical communication system. The optical transceiver includes a transmitter including an isolator and converting an external input signal into an optical transmit signal, an optical filter reflecting some of the optical transmit signal and transmitting the other of the optical transmit signal, an optical fiber transmitting the optical transmit signal transmitted by the optical filter to a counterpart optical transceiver, a receiver receiving an optical receive signal from the counterpart optical transceiver via the optical fiber, and a body enclosing a portion of the transmitter, the optical filter, a portion of the optical fiber and a portion of the receiver. An incidence angle (θ2) formed between a central axis of the transmitter and a central axis of the optical fiber is adjusted to allow the optical transmit signal to be obliquely incident into the optical fiber in order to reduce reflection of the optical transmit signal by the optical fiber without coupling with the optical fiber when the transmitter transmits the optical transmit signal to the optical fiber.
Abstract:
Disclosed herein is a bi-directional optical sub-assembly structured to reduce reflection noise. The bi-directional optical sub-assembly includes an optical fiber; a transmitter transmitting an optical transmit signal having passed through a 45° filter to the outside through the optical fiber, a receiver receiving an optical receive signal which is received from the outside through the optical fiber, is reflected by the 45° filter and passes through a 0° filter; a body encompassing a part of the optical fiber, a part of the transmitter and a part of the receiver; a cap housing encompassing a part of the transmitter and including an opening to provide a passage for the optical transmit signal from the transmitter to the optical fiber, and a filter holder having the 45° filter and the 0° filter attached thereon within the body. The opening of the cap housing is set to have a minimum diameter Xmin and a maximum diameter Xmax so as to transmit the optical transmit signal without loss and to prevent the optical transmit signal from entering back to the transmitter after the optical transmit signal is reflected by the optical fiber, and the filter holder includes a first passage connected to the 45° filter and a second passage connected to the 0° filter. The first passage is set to have a predetermined filter holder size dh so as to prevent the optical transmit signal from entering the receiver after the optical transmit signal is reflected by the optical fiber.
Abstract:
Provided are an Internet protocol (IP) converged mobile access gateway for a 3rd generation (3G) mobile service and a service method using the same. The IP converged mobile access gateway including: an access controller adapted to exchange a control signal with the base station and perform mobility control for the terminal and session control for a service request; a transport controller adapted to perform routing database information management and routing protocol processing for packet routing; and a transport executor adapted to set a tunnel with the base station for user data transmission according to control information sent from the access controller, configure a packet data convergence protocol (PDCP) for a logical connection with the terminal, and interwork with the transport controller to perform packet routing and forwarding.
Abstract:
A system for assisting fuel-efficient driving includes a storage unit for storing a shift pattern map, a collection unit for collecting the driving state information of a vehicle, a driving state calculation unit for calculating a current driving state and a target driving region on the basis of the information from the collection unit and the shift pattern map, and a display control unit for displaying the current driving state and the target driving region on a display to make it possible to compare the current driving state and the target driving region on the basis of at least acceleration or speed.
Abstract:
The present invention relates to an internet protocol (IP) mobile communication system and a session initiation method thereof. In the IP mobile communication system, a session initiation process using a session initiation protocol is performed for real-time mobile multimedia communication. At this time, not only multimedia codec but also session and quality of service (QoS) information is negotiated from a transmitting terminal to a receiving terminal, and is negotiated between relating network elements. An access manager controls a mobile access router which is a gateway of an access network according to the negotiated session and QoS information. Therefore an additional QoS negotiation process is not necessary for a session guaranteeing the QoS between a terminal and the mobile access router, between the mobile access routers, and between the mobile access router and the receiving terminal.