Abstract: Provided is a cathode active material having a composition represented by the following Formula I: LiFe(P1-XO4) (I) wherein a molar fraction (1-x) of phosphorus (P) is in the range of 0.910 to 0.999, to allow operational efficiency of the cathode active material to be leveled to a lower operational efficiency of an anode active material and improve energy density of the cathode active material. Furthermore, a cathode active material, wherein a molar fraction (1-x) of phosphorus (P) is lower than 1, contains both Fe2+ and Fe3+, thus advantageously preventing structural deformation, improving ionic conductivity, exhibiting superior rate properties and inhibiting IR drop upon charge/discharge, thereby imparting high energy density to batteries.

Abstract: Disclosed is a method for preparing a lithium metal phosphate represented by the following Formula 1 by using a mixture of a metal (M) with a metal oxide containing the same metal: LixMyPO4??[Formula 1] wherein M is a transition metal element selected from Group 3 to 12 elements in the Periodic Table, Mg, Al, Ga and B; 0.05?x?1.2; and 0.8?y?1.2. Also, an electrode comprising the lithium metal phosphate as an electrode active material, and a secondary battery comprising the electrode are also disclosed.

Abstract: Provided is a beta-based titanium alloy with a low elastic modulus, including no elements harmful to the human body and having excellent biocompatibility. The beta-based titanium alloy includes titanium (Ti), niobium (Nb) and zirconium (Zr) as major alloying elements, and further includes tantalum (Ta), hafnium (Hf), molybdenum (Mo), tin (Sn), and the like. The beta-based titanium alloy has a much lower elastic modulus than the typical biomedical titanium alloys, and thus can resolve the problem of so-called “stress shield effect.” Therefore, the beta-based titanium alloy can be widely used as a material for general civilian goods such as eyewear frames and headsets and sports and leisure goods, as well as a biomedical material for artificial bones, artificial teeth and artificial hip joints.

Abstract: Disclosed herein is a cathode active material for a lithium secondary battery, including lithium transition metal oxide, where the lithium transition metal oxide is coated with carbon particles and a polymer resin at a surface thereof, and the polymer resin is a substance inactivated by an electrolyte for a lithium secondary battery and an organic solvent and has a melting point of at least 80° C. A lithium secondary battery having the disclosed cathode active material has advantages of improving rate properties and high temperature stability, so as to provide excellent cell characteristics.

Abstract: Disclosed herein is a cathode active material based on lithium nickel oxide represented by Formula 1, wherein the lithium nickel oxide has a nickel content of at least 40% among overall transition metals and is coated with a polymer having a melting point of 80 to 300° C. at a surface thereof. A lithium secondary battery having the disclosed cathode active material has advantages of not deteriorating electrical conductivity while maintaining high temperature stability, so as to efficiently provide high charge capacity.

Abstract: Provided are a distributed repeater for repeating output signals identical to input signals through a channel different from that of main transmitter signals but identical to channels of other distributed repeaters, and a distributed repeating method thereof. The distributed repeater includes: a pre-processing unit configured to receive a radio frequency (RF) signal transmitted from an external device and demodulate the RF signal into a baseband signal; an equalizer configured to equalize the baseband signal to correct a distortion occurring on a transmission channel; an identification signal generation and insertion unit configured to generate an identification signal for identification of the distributed repeater and network conditioning, and insert the identification signal in the equalized baseband signal; and a post-processing unit configured to convert the baseband signal from the identification signal generation and insertion unit into an RF signal, and send the RF signal.

Abstract: Provided are an on-channel repeater and an on-channel repeating method.

Abstract: Provided is an apparatus and method for estimating inverse channel of a repeater's receiving channel, which ensures stability and causality by generating a time-domain filter coefficient having information on an inverse channel of repeater's receiving channel from a signal transmitted from a main transmitter or another repeater. The apparatus includes: a channel estimator for estimating a channel established by a transmission path from a received signal; an inverse minimum phase filter coefficient generator for generating inverse channel of a minimum phase channel from the estimated channel, and converting the inverse channel of the minimum phase channel into a time-domain filter coefficient; an inverse group delay filter coefficient generator for generating a time-domain filter coefficient by using the estimated channel and the minimum phase channel; and a combiner for generating an inverse channel of a receiving channel in a time domain by combining the filter coefficient and the filter coefficient.

Abstract: Provided are an on-channel repeater and a method thereof. The on-channel repeater can extract reception channel information from signals transmitted from a main transmitter or another repeater, compensate for channel distortion caused on a transmission channel by inversely reflecting the extracted reception channel information to the received signals, and transmit the channel-distortion compensated signals through the same channel as a reception channel, and a method thereof.

Abstract: Provided is a frequency synchronizing apparatus and method that can synchronize center frequency of radio frequency (RF) transmission signals among distributed repeaters using identical signals as mother signals by reflecting sampling information acquired in a timing recovery process of reception signals transmitted from a main transmitter or other repeaters. The apparatus for synchronizing frequency in distributed repeaters includes: a timing recoverer for compensating sampling timing offset of reception signals; an intermediate frequency (IF) timing offset information reflector for applying the sampling timing offset information extracted in the timing recoverer to digital-to-analog conversion; and a radio frequency (RF) timing offset information reflector for applying the sampling timing offset information extracted in the timing recoverer to RF up-conversion as a reference signal.

Abstract: A repeater converts a frequency of a received signal based on a local oscillating frequency and transmits a transmitting signal of a frequency that is different from the frequency of the received signal. Here, the local oscillating frequency includes a local oscillating error that may be different in a plurality of repeaters. Accordingly, the repeater cancels the local oscillating frequency error itself in a frequency conversion so that transmitting frequencies between the plurality of repeaters may be identical.

Abstract: A repeater having different input and output frequencies converts a signal received with the input frequency to a first intermediate frequency signal based on a local oscillating frequency for intermediate frequency conversion, and converts the first intermediate frequency signal to a second intermediate frequency signal by performing digital processing on the first intermediate frequency signal. Then, the repeater generates a first frequency tone signal that corresponds to a difference between the input and output frequencies, and generates a second frequency tone signal from the local oscillating frequency for intermediate frequency conversion and the first frequency tone signal. The repeater up-converts the second intermediate frequency signal to the output frequency based on the second frequency tone signal, and transmits the signal.

Abstract: Provided is an olivine-type lithium iron phosphate having a composition represented by Formula I, comprising 0.1 to 5% by weight of Li3PO4, and comprising no Li2CO3 or, if present, comprising Li2CO3 in an amount less than 0.25% by weight: Lii+aFe1?xMx(PO4?b)Xb (I) wherein M, X, a, x and b are as defined above. The lithium iron phosphate comprises no lithium carbonate (Li2CO3) or, if present, comprises the Li2CO3 in an extremely small amount, and comprises Li3PO4 having superior electrochemical stability, thermal stability and ionic conductivity, thus advantageously imparting high-temperature and storage stability as well as stability and rate properties to lithium secondary batteries, when used as a cathode active material for the lithium secondary batteries.

Abstract: A repeater and method for an ATSC terrestrial digital TV broadcasting service.

Abstract: Disclosed is a method for preparing a lithium metal phosphate represented by the following Formula 1 by using a mixture of a metal (M) with a metal oxide containing the same metal: LixMyPO4??[Formula 1] wherein M is a transition metal element selected from Group 3 to 12 elements in the Periodic Table, Mg, Al, Ga and B; 0.05?x?1.2; and 0.8?y?1.2. Also, an electrode comprising the lithium metal phosphate as an electrode active material, and a secondary battery comprising the electrode are also disclosed.

Abstract: Provided is a cathode mix for lithium secondary batteries, comprising a cathode active material having a composition represented by the following Formula I: LiFe(P1-XO4) (I) wherein a molar fraction (1-x) of phosphorus (P) is in the range of 0.910 to 0.999, to allow operational efficiency of the cathode active material to be leveled to a lower operational efficiency of an anode active material and improve energy density of the cathode active material. The cathode mix maximizes operational efficiency of batteries, minimizes electrode waste and thus reduces manufacturing costs of batteries. Furthermore, The cathode active material, wherein a molar fraction (1-x) of phosphorus (P) is lower than 1, according to the present invention contains both Fe2+ and Fe3+, thus advantageously causing no structural deformation, improving ionic conductivity, exhibiting superior rate properties, inhibiting IR drop upon charge/discharge, thereby imparting high energy density to batteries.

Abstract: Provided is an olivine-type lithium iron phosphate composed of secondary particles having a mean particle diameter (D50) of 5 to 100 ?m, formed by aggregation of primary particles having a mean particle diameter (D50) of 50 to 550 nm, wherein the primary and secondary particles have a composition represented by Formula I below and the secondary particles have a porosity of 15 to 40%: Li1+aFe1-xMx(PO4-b)Xb (I) wherein M, X, a, x and b are as defined above. The olivine-type lithium iron phosphate is in the form of secondary particles, thus imparting a high bulk density to lithium secondary batteries and exhibiting superior process efficiency due to shortened mixing time, when used to fabricate the lithium secondary batteries.

Abstract: Disclosed is a method for preparing a lithium-metal composite oxide, the method comprising the steps of: (a) mixing an aqueous solution of one or more transition metal-containing precursor compounds with an alkalifying agent and a lithium precursor compound to precipitate hydroxides of the transition metals; (b) mixing the mixture of step (a) with water under supercritical or subcritical conditions to synthesize a lithium-metal composite oxide, and drying the lithium-metal composite oxide; and (c) subjecting the dried lithium-metal composite oxide either to calcination or to granulation and then calcination. Also disclosed are an electrode comprising the lithium-metal composite oxide, and an electrochemical device comprising the electrode. In the disclosed invention, a lithium-metal composite oxide synthesized based on the prior supercritical hydrothermal synthesis method is subjected either to calcination or to granulation and then calcination.

Abstract: In a digital broadcasting signal transmission system, a transmission frame includes a frame body and a frame header, and the frame body is divided into a plurality of sub-bands in the frequency domain and is divided into a plurality of symbols in the time domain. The frame header is provided in the former part of the transmission frame and is transmitted with a signal in the time domain. The frame body includes a plurality of services, and the services respectively receive at least one sub-band and at least one symbol. The frame header includes information on the plurality of services, and information on the plurality of services includes information on the sub-band and the symbol to which the services are allocated, information on channel encoding levels of the services, and information on digital modulation levels of the services.

Abstract: Provided are an on-channel repeater and method for increasing output of the on-channel repeater by removing feed-back signals caused by low isolation of transmission/reception antennas. The on-channel repeater includes: a receiver for receiving RF signals and converting the RF signals into baseband signals; a subtractor for subtracting replicas of feedback signals from the received signal; an inverse channel estimator for estimating inverse of a reception channel and generating a filter tab coefficients; a first adaptive filter for compensating for channel distortion of the subtracted signal; a transmitter for converting the signals whose channel distortion is compensated into an RF signal and performing radio transmission; a down-converter for down-converting the RF signal converted by the transmitter into the baseband signal; and a replica generator for calculating replicas and feeding back the replicas to the subtractor. The present invention is applied to the on-channel repeater.