摘要:
A mobile communication system, a transmitter includes a first transmission antenna and a second transmission antenna, and the first and second transmission antennas transmit signals through at least one odd carrier and at least one even carrier. The transmitter determines a first symbol and a second symbol to be used for initial channel estimation of a receiver, encodes the first symbol and the second symbol by a preset transmit diversity scheme for a preset time, and transmits the encoded first and second symbols to the receiver through odd carriers and even carriers of the first transmission antenna and the second transmission antenna. The receiver receives a signal for the preset period, estimates channel frequency responses of odd carriers of the first transmission antenna and channel frequency responses of even carriers of the second transmission antenna, and estimates channel frequency responses of even carriers of the first transmission antenna and channel frequency responses of odd carriers of the second transmission antenna by using the estimated channel frequency responses.
摘要:
The present invention relates to a slurry for use in metal chemical-mechanical polishing (CMP) and a preparation method thereof. More particularly, the invention relates to a slurry for use in metal CMP, in which iron ions or divalent or higher valent metal ions are physico-chemically adsorbed on colloidal silica particles in the form of particles by a reduction, hydrolysis, impregnation or precipitation method, as well as a preparation method thereof. The slurry useful for metal CMP prepared according to the present invention has a uniform particle size distribution, and shows increased efficiencies as an oxidation catalyst and polishing slurry chemically adsorbed with metal particles, as compared to the prior metal CMP slurry distributed with metal ions. Also, the inventive slurry has long-term storage stability, since it does not show coagulation and precipitation phenomena even after it is stored for more than one year without a dispersant or a dispersion stabilizer. Furthermore, the prior fumed silica contains a large amount of environment-harmful substances for distribution stabilization, such as surfactants and amine compounds, whereas the inventive colloidal silica contains no environment-harmful substances as described above, and thus, is eco-friendly.
摘要:
A display apparatus is provided with a panel to display a picture thereon. The display apparatus comprises an inverter to convert DC power into AC power. The display apparatus also includes at least one lamp unit comprising a lamp body and a lamp electrode part provided in at least one of opposite ends of the lamp body to receive an electric power. A transformer is arranged adjacent to the lamp electrode part to boost up a voltage of the electric power output from the inverter to supply the electric power with the boosted voltage as a driving power to the lamp unit.
摘要:
A receiving apparatus in an OFDM communication system, in which the receiving apparatus includes a serial-to-parallel converter that converts a serial signal received through an antenna to parallel signals. A pre-processor processes an nth symbol converted in the serial-to-parallel converter using an (n−1)th symbol and an (n+1)th symbol. A Fourier transformer Fourier-transforms the output of the pre-processor and an equalizer equalizes a Fourier-transformed signal. A deinterleaver deinterleaves an equalized signal, a decoder decodes a deinterleaved signal, and a parallel-to-serial converter converts parallel decoded signal to a signal stream.
摘要:
A mobile communication system, a transmitter includes a first transmission antenna and a second transmission antenna, and the first and second transmission antennas transmit signals through at least one odd carrier and at least one even carrier. The transmitter determines a first symbol and a second symbol to be used for initial channel estimation of a receiver, encodes the first symbol and the second symbol by a preset transmit diversity scheme for a preset time, and transmits the encoded first and second symbols to the receiver through odd carriers and even carriers of the first transmission antenna and the second transmission antenna. The receiver receives a signal for the preset period, estimates channel frequency responses of odd carriers of the first transmission antenna and channel frequency responses of even carriers of the second transmission antenna, and estimates channel frequency responses of even carriers of the first transmission antenna and channel frequency responses of odd carriers of the second transmission antenna by using the estimated channel frequency responses.
摘要:
In a backlight assembly and an LCD device having the same, a backlight assembly includes a main light source and an auxiliary light source. The main light source is under an LCD panel that displays an image. The main light source generates a main light. The auxiliary light source generates an auxiliary light. Therefore, luminance of the backlight assembly becomes more uniform, and an image display quality of the LCD device is improved.
摘要:
Disclosed is a multicarrier-based wireless communication system including a base station for providing a multiple access service to terminals which filter multitone transmitting signals through filters and transmit the filtered signals. A transmitter of the respective terminals includes a multiplexer for multiplexing an input signal and outputting the signal as a plurality of transmitting signals, at least one filter bank for filtering the plurality of transmitting signals, an inverse fast Fourier transformer for executing inverse fast Fourier transform of the filtered transmitting signals output from the filter bank, and a filter information generator for providing filter information to the filter bank. Since the transmitter of the present invention distinguishes users from each other by a filter and thus no synchronization is required between users, which causes a problem in an uplink of the multicarrier-based wireless communication system, system performance can be expected to be improved.
摘要:
A preprocessing apparatus and method for a transmitter and a receiver to prevent system performance degradation caused by Inter-Channel Interference (ICI) or inter-symbol interference (ISI) in an OFDM system. In the OFDM system using N carriers having different frequency bands and K carriers of the N carriers designated as redundant carriers, the transmitter renders ICI-causing parts to be zeroes in a data frame, when a cyclic prefix is not longer than a channel impulse response. Therefore, the ICI is prevented. The receiver eliminates the ISI involved in a current frame using an interference estimated from a previous data frame. Therefore, noise spread caused by the use of redundant carriers is prevented and system complexity is remarkably reduced.
摘要:
A hybrid circuit board includes a first circuit board and a second circuit boards. The first circuit board includes a first body having a slot, and a first circuit pattern formed on the first body and extended to the slot. The second circuit board includes a second body, a protruding portion, a second circuit pattern, and a separating member. The protruding portion extends from the second body. The protruding portion is inserted into the slot of the first circuit board to combine the second circuit board to the first circuit board. The second circuit pattern is formed on the second body to be extended to the protruding portion, so that the second circuit pattern is electrically connected to the first circuit pattern of the first circuit board. The separating member is disposed between the second body and the protruding portion to separate the protruding portion from the second body.
摘要:
A hybrid circuit board includes a first circuit board and a second circuit boards. The first circuit board includes a first body having a slot, and a first circuit pattern formed on the first body and extended to the slot. The second circuit board includes a second body, a protruding portion, a second circuit pattern, and a separating member. The protruding portion extends from the second body. The protruding portion is inserted into the slot of the first circuit board to combine the second circuit board to the first circuit board. The second circuit pattern is formed on the second body to be extended to the protruding portion, so that the second circuit pattern is electrically connected to the first circuit pattern of the first circuit board. The separating member is disposed between the second body and the protruding portion to separate the protruding portion from the second body.