Abstract: A method of determining a number of antennas, includes calculating a power used by a transmitting device. The method further includes calculating a channel capacity of the transmitting device. The method further includes determining a number of antennas of the transmitting device to be used based on the power and the channel capacity.

Abstract: A method and apparatus for user scheduling in a multi-user multiple input multiple output (MIMO) communication system are provided. The method includes identifying a user group comprising user terminals. The method further includes comparing power consumptions based on the user group. The method further includes scheduling the user terminals based on the comparing.

Abstract: A method for determining a transmission power in a multi-input multi-output (MIMO) system based on a cooperative transmission is provided. The method includes setting a power constraint condition of a transmitter and target quality information of a receiver. The method further includes determining the transmission power to be allocated to the transmitter to transmit the data to the receiver based on the power constraint condition and the target quality information.

Abstract: Disclosed are a system and a method that generates image data that represent a speaker to be distinguished, and enables a mobile terminal to provide a video conference service using the image data that distinguishes the speaker. A video conference apparatus may include a speaker distinguishing unit to distinguish, as a speaker, a participant who is speaking from a plurality of participants in the video conference and an image data generating unit to generate image data that represents the distinguished participant differently from other participants.

Abstract: Provided is a method and device for increasing energy efficiency by adaptively performing clipping with respect to an input signal. The method may adaptively determine a clipping ratio (CR) based on a modulation method of the communication device and perform clipping based on the determined CR.

Abstract: A system for saving energy through control of a sleep mode, and a method of operating the system are provided. The energy-saving system may enable a proxy device to maintain a minimum basic setup necessary for a communication when a host device enters a sleep mode, and may omit an operation performed based on the basic setup when the host device switches to a communication mode, thereby enabling a smooth switch between the sleep mode and the communication mode.

Abstract: A system for allocating a wireless resource for a Space Division Multiple Access (SDMA) communication is provided. The system for allocating the wireless resource for the SDMA communication includes: a channel state recognition unit to recognize a channel state of wireless channels generated among adjacent nodes including a source node, a relay node, and a destination node; and a wireless resource allocation unit to control at least one of an amount of channel state information fed back from the destination node to the source node, and a relay level of a relay signal, the relay signal being generated by relaying a source signal transmitted from the source node, according to the channel state.

Abstract: Provided are a central processing unit (CPU) and method for executing a branch instruction of a CPU, which can protect user's data by preventing an error due to a computer virus and a hacker is provided. The CPU includes: a branch instruction verification unit which verifies whether a branch instruction is valid; and a branch instruction execution unit which executes the branch instruction when the branch instruction is valid. The method includes: verifying whether the branch instruction is valid; and not executing the branch instruction when the branch instruction is invalid.

Abstract: Disclosed are a system and a method that generates image data that represent a speaker to be distinguished, and enables a mobile terminal to provide a video conference service using the image data that distinguishes the speaker. A video conference apparatus may include a speaker distinguishing unit to distinguish, as a speaker, a participant who is speaking from a plurality of participants in the video conference and an image data generating unit to generate image data that represents the distinguished participant differently from other participants.

Abstract: A multicast packet forwarding apparatus and method that can combine an internal processor of a multicast packet processor into a forwarding unit and a packet duplicator in order to minimize delay in the processing time of a forwarder and a packet transmitter. In the apparatus, a packet receiver is adapted to receive unicast and multicast packets. A forwarding unit has a unicast forwarder for forwarding a unicast packet to a destination when the packet receiver receives the unicast packet, and a multicast forwarder for multicasting a multicast packet to respective output interfaces when the packet receiver receives the multicast packet. A packet duplicator is adapted to convert the multicast packet output from the multicast forwarder into a several unicast packets. A packet dispatcher is adapted to reintroduce the unicast packets converted by the packet duplicator to the forwarding unit again.

Abstract: A system and method for interface translation between a system packet interface level 3 (SPI-3) defines an interface between a physical device (PHY device) and a link layer device, and a gigabit media independence interface (GMII) which defines an interface between a media access control (MAC) portion of a gigabit Ethernet and a physical device. The system includes a translation circuit for translating a GMII reception signal, received from a GMII interface device, into an SPI-3 reception signal synchronized with an SPI3 reference clock, and for translating an SPI-3 transmission signal, received from an SPI-3 interface device, into a GMII transmission signal synchronized with a GMII reference clock.

Abstract: In transferring a service context during hand-over of a mobile node located in a wireless mesh network, transfer boundaries are set according to positions spaced from an initial Access Point (AP) to which the mobile node is initially connected to, AP types being determined based upon the set transfer boundaries. Prior to hand-over of the mobile node in response to its movement, a service context is transferred to APs arranged in a moving direction of the mobile node based upon context transfer policies according to the determined AP types.

Abstract: A system for allocating a wireless resource for a Space Division Multiple Access (SDMA) communication is provided. The system for allocating the wireless resource for the SDMA communication includes: a channel state recognition unit to recognize a channel state of wireless channels generated among adjacent nodes including a source node, a relay node, and a destination node; and a wireless resource allocation unit to control at least one of an amount of channel state information fed back from the destination node to the source node, and a relay level of a relay signal, the relay signal being generated by relaying a source signal transmitted from the source node, according to the channel state.

Abstract: Provided are a central processing unit (CPU) and method for executing a branch instruction of a CPU, which can protect user's data by preventing an error due to a computer virus and a hacker is provided. The CPU includes: a branch instruction verification unit which verifies whether a branch instruction is valid; and a branch instruction execution unit which executes the branch instruction when the branch instruction is valid. The method includes: verifying whether the branch instruction is valid; and not executing the branch instruction when the branch instruction is invalid.

Abstract: An IP address look-up device is for looking up an IP address of an IP packet in order to forward the IP packet. The device includes a ternary CAM including pairs of data string and mask string, with the data string having a prefix of an IP address and the mask string representing a length of the prefix, and having routing entries stored in physical segments, respectively, without regard to order of prefix length, the ternary CAM functioning to compare a search key as a destination address of the IP packet to be forwarded, with the routing entries, set a match line of a matching routing entry, and output a mask string of the matching routing entry; and a priority encoder functioning to compare prefix lengths of mask strings outputted in correspondence to set match lines when at least one match line is set in the ternary CAM, determine, as an LPM entry, a routing entry corresponding to a longest mask string, and output a physical address of the LPM entry on the basis of a match line of the LPM entry.

Abstract: A passive optical network system is disclosed that simultaneously provides both broadcasting service and data service. The passive optical network (PON) amplifies the optical signals for the broadcasting service in an optical amplifier media of the local office by pumping optical signals generated from the central office and provides the optical signals for the broadcasting service to the subscriber terminals. Therefore, the present invention can simultaneously provide broadcasting service and data service for more subscribers without reducing the number of subscribers to the PON. Also, the present invention uses a plurality of optical sources for the data service and the broadcasting service and receives the optical signals generated from the optical sources by using a plurality of optical receivers in the subscriber terminals, and thus can provide a greater amount and variety of data services and broadcasting services.

Abstract: In allocating bandwidth using a Resilient Packet Ring (RPR) fairness mechanism in a node connected to an RPR network, when congestion occurs, an amount of traffic that the node has transmitted to a ring during one aging interval is stored together with its own identifier in a fairness message as a fairness transmission rate to be advertised to its own upstream nodes. The amount of traffic transmitted from the upstream node during the aging interval is measured and stored. When the congestion has been solved, an available bandwidth is calculated with reference to the fairness transmission rate and the amount of traffic transmitted from the upstream nodes, and the fairness transmission rate is calculated to fairly allocate the available bandwidth to the upstream nodes so that the fairness transmission rate is transmitted to the upstream nodes.

Abstract: Disclosed is a broadcast/communication unified passive optical network system.

Abstract: An optical multi-ring network for burst data communication is disclosed. The multi-ring network includes a plurality of optical single-ring networks having a plurality of optical add/drop routers connected with each other through fiber links, and a core optical router for supporting communication between the optical single-ring networks. The core optical router includes a wavelength division demultiplexing section for demultiplexing optical signals received from the each single-ring network and outputting the demultiplexed optical signals as channels whose wavelengths are different from each other; a branching section for branching off and outputting a portion of each channel; and a switching section for switching each channel to a path directed to the destination of each channel according to a first control signal.

Abstract: A WDM optical source, in adopting a spectrum-sliced method, advantageously needs neither an optical source with specific generation wavelength nor a wavelength-stabilizing circuit for stabilizing wavelength. Affording high power and a very narrow line width, the WDM optical source can provide a broadcasting service without signal distortion by a chromatic dispersion effect and also avoids the expense of an amplifier and/or external modulator, thereby relieving subscribers of the economical burden. The practical use of WDM-PON and of WDM-PON using an inventive WDM optical source can therefore be brought to fruition and broadcasting service can be provided economically.