Abstract: A method of transmitting control information includes dividing frequency bandwidth into ranges to which the same PMI (precoding matrix index) is applied, obtaining multiple antenna information by the range to which the same PMI is applied and transmitting the multiple antenna information. Since multiple antenna information is transmitted by the unit of a range to which the same PMI is applied, radio resources allocated for transmitting the multiple antenna information may be reduced, thereby enhancing data transmission efficiency.

Abstract: Provided is a spatial phase shifting interferometer using a multi wavelength. More particularly, provided is a spatial phase shifting interferometer using a multi wavelength capable of more rapidly measuring a precise shape of a measurement object by simultaneously oscillating laser having different wavelengths and passing the oscillated laser through a beam splitter and a lens to analyze an interference fringe of the measurement object.

Abstract: Provided are an absolute position measurement method, an absolute position measurement apparatus, and a scale. The scale includes a scale pattern formed by replacing repeatedly arranged pseudo-random-codes with a sequence of a linear feedback shift register of N stages using a first symbol with first width representing a first state and a second symbol with second width representing a second state. The first is divided into two or more first symbol areas of different structures, and the second symbol is divided into two or more second symbol areas of different structures. There is at least one overlap area in which the first symbol and the second symbol overlap each other to have the same structure.

Abstract: Provided are a thickness measuring apparatus and a thickness measuring method. The thickness measuring method includes irradiating first laser beam of a first wavelength ?1 to a transparent substrate and measuring intensity of first laser beam transmitting the transparent substrate; irradiating second laser beam of a second wavelength ?2 to the transparent substrate and measuring intensity of second laser beam transmitting the transparent substrate; and extracting a rotation angle on a Lissajous graph using the first and second laser beams transmitting the transparent substrate. A phase difference between adjacent rays by multiple internal reflection of the first laser beam and a phase difference between adjacent ray by multiple internal reflection of the second laser beam is maintained at ?/2.

Abstract: Provided are a transparent substrate monitoring apparatus and a transparent substrate monitoring method. The transparent substrate monitoring apparatus includes a light emitting unit emitting light; a double slit disposed on a plane defined in a first direction and a second direction intersecting a propagation direction of incident light and includes a first slit and a second slit spaced apart from each other in the first direction to allow the light to pass therethrough; an optical detection unit measuring an intensity profile or position of an interference pattern formed on a screen plane; and a signal processing unit receiving a signal from the optical detection unit to calculate an optical phase difference or an optical path difference.

Abstract: Provided are a method of generating a message authentication code and an authentication device and an authentication request device using the method. The method includes generating a second secret key by encrypting seed data, a first secret key, and first auxiliary data using an encryption algorithm; and encrypting the seed data, the second secret key, and second auxiliary data using the encryption algorithm, wherein the encryption algorithm receives data of a preset base number of bits and encrypts the received data, and the number of bits of the second auxiliary data varies according to a difference between the number of bits of the first secret key and the number of bits of the second secret key.

Abstract: A collaborative MIMO method using a sounding channel in a multi-cell environment is disclosed. The method includes acquiring, by a first base station providing a service for a first cell, first CSI of a first downlink channel between the first base station and a mobile station, transmitting, to a second base station, a signal including information requesting that the second base station providing a service for a second cell acquire second CSI of a second downlink channel between the second base station and the mobile station, and acquiring, by the second base station, the second CSI. The mobile station is served by the first base station.

Abstract: A method for transmitting a precoded signal in a collaborative multiple-input multiple-output (MIMO) communication system is described. A method for receiving a precoded signal in a MIMO communication system includes estimating, by a mobile station, channels for one or more base stations through signals received from the one or more base stations including a serving base station, transmitting precoding matrix indexes of the one or more base stations determined based on the estimated channels to the serving base station, and receiving signals precoded by the one or more base stations based on the precoding matrix index.

Abstract: The present invention relates a method for transmitting and receiving data in a mobile communication system. More specifically, the invention relates to a method through which a terminal in a cell boundary receives data in a mobile communication system that supports MIMO (Multi Input Multi Output). The method comprises: a step for receiving a first data stream transmitted through multiple transmission antennas from a serving base station, a step for pre-coding a second data stream to make the time delay of the second data stream be different from that of the first data stream and receiving the second data stream from a collaborating base station, and a step for restoring the data based on the first and second data streams.

Abstract: A method of transmitting control information in a multiple antenna system includes generating a dedicated pilot including a weight and a weight index indicating the weight, and transmitting the dedicated pilot. Detection performance can be improved when control information such as a weight and a weight index is transmitted on a pilot.

Abstract: A method for transmitting and receiving data in a cooperative Multiple-Input Multiple-Output (MIMO) mobile communication system is disclosed. The method includes selecting a transmission path for transmitting precoding-related feedback control information to one or more cooperative base stations operating in the cooperative MIMO mode, and transmitting the precoding-related feedback control information to the one or more cooperative base stations through the selected transmission path.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: A method is disclosed for avoiding inter-cell interference in a closed-loop multiple-input multiple-output (MIMO) system using a plurality of codebooks. A base station of a serving cell transmits information about codebooks used in an interfering cell among the plurality of codebooks to a mobile station. The transmission of the information may be made at the request of the mobile station. Alternatively, the mobile station may directly measure information about codebooks used in the interfering cell among the plurality of codebooks. The mobile station measures restricted precoding matrix indexes (PMIs) or requested PMIs based on the codebook information. The measured PMIs are transmitted to the interfering cell and are used to restrict the use of a PMI in the interfering cell.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: Precoding methods and method for performing precoding and methods of transmitting feedback information for precoding or transmitting a signal using a multi-codebook and method of transceiving precoding information in a multi-antenna system, where a signal transmitting method in a multi-antenna system, and more particularly, a method of transceiving precoding matrix information for a multi-input multi-output (MIMO) system is disclosed. The present invention proposes a method of performing communications using an expanded unitary matrix generated from shifting a phase of a base unitary matrix. The present invention is applicable to single user MIMO, multi-user MIMO, beam forming, etc.

Abstract: Methods of controlling a transmission power and configuring a codebook in a multi-antenna system to solve a transmission power unbalance between antennas are disclosed. The method of transmitting data in a multi-antenna system includes (A) transmitting one or more pilot signals within a first symbol region through a first antenna unit, and (B) transmitting one or more pilot signals within a second symbol region through a second antenna unit, wherein data within the first symbol region is transmitted through the second antenna unit, and data within the second symbol region is transmitted through the first antenna unit. According to the present invention, since a transmission power unbalance between antennas is solved, a transmission power can be uniformly assigned to each antenna and channel estimation can be easily performed. Moreover, a power amplifier having a uniform amplification range can be used and designed.

Abstract: A method for avoiding an inter-cell interference (ICI) in a multi-cell environment is disclosed. The method includes restricting the use of a PMI in an interfering cell so as to improve a reception performance of a mobile station located at an interfered cell edge. The mobile station measures a restricted-PMI of the interfering cell, which is prohibited from use in the interfering cell, and transmits the measured restricted PMI to the interfering cell. The use of the restricted PMI is prohibited from use in a mobile station in the interfering cell.

Abstract: The present invention pertains to a device and a method for measuring a via hole of a silicon wafer, wherein it is possible to precisely measure the depth of the via hole without damaging the wafer. Broadband infrared light is radiated to a silicon wafer which has a superior light transmission property, so that the depth of the via hole may be measured from the light which is reflected from each boundary surface of the wafer and the interference signal of reference light. The via hole measuring device according to the present invention includes: a light source unit for generating broadband infrared light; and an interferometer for radiating the light generated from the light source unit to a silicon wafer, so as to measure the depth of a via hole formed on the wafer according to the spectrum period of the interference signal of the light, which is reflected from the silicon wafer.

Abstract: A method for allocating fractional frequency reuse (FER) resources to perform cooperative MIMO in a multi-cell environment is disclosed. A cell which requests FER resources decides a band for cooperative MIMO with its neighboring cell, and requests the neighboring cell to allocate the decided band for cooperative MIMO. A cell which receives FER resource request receives a request from a neighboring cell to allocate some or all of FER bands allocated to the neighboring cell as a band for cooperative MIMO, decides whether to grant the request, and allocates some or all of the requested FER bands as the band for cooperative MIMO with the neighboring cell if the request is granted.

Abstract: A Universal Serial Bus (USB) connector with a connector housing is provided with at least one soldering part and at least one reinforcement part around its circumference. The USB connector includes: a connector housing; one or more soldering parts formed by cutting and unfolding predetermined areas around the circumference of the connector housing; and one or more reinforcement parts, each of which is formed by bending an end of the connector housing. The reinforcement parts being engaged with the soldering parts to support and reinforce the soldering parts, respectively.