Abstract: A built-in antenna device for an electronic device for communication is provided. The antenna device includes a substrate, an antenna radiator, and a transmission line. The substrate includes a grounding region and a non-grounding region. The antenna radiator is disposed in the non-grounding region of the substrate and fed from a feeding portion provided to the substrate. The transmission line branches from the antenna radiator and is disposed in vicinity of the grounding region to have a predetermined length and a predetermined width. The antenna device controls reactance by coupling the transmission line with the grounding region to allow the antenna radiator to operate in at least one desired band.

Abstract: A Universal Serial Bus (USB) apparatus for USB communication is provided. The USB apparatus includes a Printed Circuit Board (PCB) including a circuit for communicating data with an external device according to a USB communication standard, a connector for connecting to a USB terminal of the external device, and a noise reduction circuit connected between an output terminal of the PCB and the connector for reducing noise of a data signal. The noise reduction circuit includes a common-mode filter for removing harmonic components generated between a ‘+’ data signal and a ‘?’ data signal and passing the ‘+’ data signal and the ‘?’ data signal, which operate in a differential mode.

Abstract: A Multiple Input Multiple Output (MIMO) antenna apparatus is provided. The apparatus includes antenna devices that operate in respective resonant frequency bands. The apparatus also includes a main board comprising a device region and a ground region. The antenna devices are disposed on the device region. The ground plate is disposed on the ground region for grounding the antenna devices. The apparatus also includes at least one isolation device having a negatively charged line that protrudes from the ground plate and extends between the antenna devices on the device region, and a positively charged line that extends around the negatively charged line and connects the antenna devices to each other. The isolation device induces an electromagnetic wave that is generated by the antenna devices between the negative and positively charged lines to isolate the antenna devices from each other.

Abstract: A built-in antenna device for an electronic device for communication is provided. The antenna device includes a substrate, an antenna radiator, and a transmission line. The substrate includes a grounding region and a non-grounding region. The antenna radiator is disposed in the non-grounding region of the substrate and fed from a feeding portion provided to the substrate. The transmission line branches from the antenna radiator and is disposed in vicinity of the grounding region to have a predetermined length and a predetermined width. The antenna device controls reactance by coupling the transmission line with the grounding region to allow the antenna radiator to operate in at least one desired band.

Abstract: A method for processing data of a received frame in a receiver of a broadband wireless communication system. The received data processing method includes extracting, from control information for data of one frame having multiple bursts, burst sizes of bursts constituting the frame and modulation scheme information applied to the frame; assigning burst identifiers (IDs) used for identifying the bursts, and assigning burst partial IDs to data concatenations having concatenation sizes based on the burst sizes and the modulation scheme information; forming, in a memory, burst regions for storing the data concatenations according to the burst IDs; dividing received data of one slot included in the frame into data concatenations based on the concatenation sizes, and decoding the data concatenations; and sequentially storing the decoded data concatenations in the memory according to a burst ID and a burst partial ID corresponding to each of the decoded data concatenations.

Abstract: A Multiple Input Multiple Output (MIMO) antenna apparatus is provided. The apparatus includes antenna devices that operate in respective resonant frequency bands. The apparatus also includes a main board comprising a device region and a ground region. The antenna devices are disposed on the device region. The ground plate is disposed on the ground region for grounding the antenna devices. The apparatus also includes at least one isolation device having a negatively charged line that protrudes from the ground plate and extends between the antenna devices on the device region, and a positively charged line that extends around the negatively charged line and connects the antenna devices to each other. The isolation device induces an electromagnetic wave that is generated by the antenna devices between the negative and positively charged lines to isolate the antenna devices from each other.

Abstract: A Universal Serial Bus (USB) apparatus for USB communication is provided. The USB apparatus includes a Printed Circuit Board (PCB) including a circuit for communicating data with an external device according to a USB communication standard, a connector for connecting to a USB terminal of the external device, and a noise reduction circuit connected between an output terminal of the PCB and the connector for reducing noise of a data signal. The noise reduction circuit includes a common-mode filter for removing harmonic components generated between a ‘+’ data signal and a ‘?’ data signal and passing the ‘+’ data signal and the ‘?’ data signal, which operate in a differential mode.

Abstract: An apparatus and method for transmitting and receiving Channel Quality Information (CQI) in a communication system. A Base Station (BS) transmits, to a Subscriber Station (SS), a request for CQI of a resource region corresponding to a frequency reuse factor K, which is designated by the BS. The BS then receives, from the SS, the CQI of the resource region corresponding to a channel quality measured by the SS. The channel quality is measured by the SS by measuring a boosted reference signal and compensating the boosted reference signal for a non-boosted signal.

Abstract: A system and method for transmitting a signal in a communication system are provided. In the signal transmitting method, a multi-FA signal is generated by combining single FA signals to be transmitted by N FAs. An operation mode is determined for N MMPAs according to a used FA strategy and adjustment of amplification characteristics of the N MMPAs is controlled according to the operation mode. The power of the multi-FA signal is divided by N, the N divided signals are amplified according to the adjusted amplification characteristics, and the power of the amplified N signals is combined.

Abstract: In a communication system, a first Downlink (DL) signal to be commonly received by all Mobile Stations (MSs) at a Base Station (BS) is generated. A second DL signal that all the MSs do not need to commonly receive is generated. The first DL signal is applied to an interference cancellation scheme. The first DL signal is transmitted in a first time interval. The second DL signal is transmitted in a second time interval.

Abstract: Disclosed is a method for controlling downlink power transmitted from a base station to subscriber stations in a mobile communication system employing an Orthogonal Frequency Division Multiple Access (OFDMA) scheme, in which data is carried from the base station to the subscriber stations by subchannels to each of which a plurality of subcarriers are assigned. The method includes the steps of receiving from the subscriber stations channel condition information of each of the subchannels together with information related to a subcarrier having a channel condition below a threshold from among at least one subcarrier included in each of the subchannels; calculating transmission power for each of the subchannels based on the received information; and transmitting each of the subchannels with the calculated transmission power, excluding the subcarrier having a channel condition below the threshold.

Abstract: An apparatus and method for transmitting and receiving Channel Quality Information (CQI) in a communication system. A Base Station (BS) transmits, to a Subscriber Station (SS), a request for CQI of a resource region corresponding to a frequency reuse factor K, which is designated by the BS. The BS then receives, from the SS, the CQI of the resource region corresponding to a channel quality measured by the SS. The channel quality is measured by the SS by measuring a boosted reference signal and compensating the boosted reference signal for a non-boosted signal.

Abstract: An apparatus and method for transmitting/receiving channel quality information (CQI) in a communication system having a frame including subchannels corresponding to the same frequency reuse factor or different frequency reuse factors. A base station (BS) allocates at least one of the subchannels in the frame to a subscriber station (SS), and sends a transmission request for a CQI for a subchannel desired to be received, to the SS. The SS measures channel quality for individual subchannels requested by the BS in response to the CQI request, and transmits the measured channel quality to the BS.

Abstract: Disclosed are an apparatus and a method for generating a preamble signal for cell identification in an OFDM mobile communication system. The method includes the steps of generating a Walsh code symbol for a cell identification by combining Walsh codewords having a predetermined length and generating the preamble signal through multiplying the Walsh code symbol by a pseudo noise (PN) code having a length identical to a length of the Walsh code symbol.

Abstract: A method for processing data of a received frame in a receiver of a broadband wireless communication system. The received data processing method includes extracting, from control information for data of one frame having multiple bursts, burst sizes of bursts constituting the frame and modulation scheme information applied to the frame; assigning burst identifiers (IDs) used for identifying the bursts, and assigning burst partial IDs to data concatenations having concatenation sizes based on the burst sizes and the modulation scheme information; forming, in a memory, burst regions for storing the data concatenations according to the burst IDs; dividing received data of one slot included in the frame into data concatenations based on the concatenation sizes, and decoding the data concatenations; and sequentially storing the decoded data concatenations in the memory according to a burst ID and a burst partial ID corresponding to each of the decoded data concatenations.

Abstract: An apparatus and method for detecting channel quality in a mobile communication system are provided. The method includes detecting a channel quality of a first channel quality detection period using a reference value of a reference signal; determining whether a reference value can be measured in a second channel quality detection period being one of a plurality of channel quality detection periods following the first channel quality detection period; and detecting a channel quality of the second channel quality detection period according to the determination.

Abstract: Disclosed is a method for transmitting/receiving a downlink signal for improving a reception capability of a mobile station in a communication system. In the method, downlink signals are transmitted such that a downlink signal having a first Modulation and Coding Scheme (MCS) level applied thereto is first transmitted, and then the downlink signals are transmitted in a sequence in which a downlink signal having an MCS level showing a smallest difference between its MCS level and the first MCS level is transmitted prior to remaining downlink signals.

Abstract: A base station power amplifier for minimizing memory effect is provided. The power amplifier includes a bias circuit which supplies a direct current (DC) power to a transistor; the transistor which amplifies the DC power provided from the bias circuit; a matching circuit which transfers maximum power to a load by reducing loss of the power amplified by the transistor; and a large capacitor which lies between the matching circuit and the transistor, reduces a low-frequency second harmonic voltage by electrically connecting directly to the matching circuit, and has a preset capacitance value.

Abstract: In a communication system, a first Downlink (DL) signal to be commonly received by all Mobile Stations (MSs) at a Base Station (BS) is generated. A second DL signal that all the MSs do not need to commonly receive is generated. The first DL signal is applied to an interference cancellation scheme. The first DL signal is transmitted in a first time interval. The second DL signal is transmitted in a second time interval.

Abstract: A transmitter and a transmitting method for forming a pseudo common beam using a plurality of antennas in a smart antenna communication system are provided, in which beams for tones of Orthogonal Frequency Division Multiplexing (OFDM) signals transmitted through a plurality of antennas are rotated at different phases around a frequency axis, such that a combined beam of the transmitted beams is equivalent to a pseudo common beam. Accordingly, a peak to average power ratio (PAPR) of the preamble signal is prevented from changing.